Cardiology Flashcards

1
Q

What is atherosclerosis?

A

Inflammatory process characterised by hardened plaques within the intima of a vessel wall. Eventually, plaque will either occlude vessel lumen resulting in a restriction of blood flow (angina) or rupture (thrombus formation - death).

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2
Q

Where do atherosclerotic plaques often occur?

A

Peripheral and Coronary arteries!

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3
Q

How are atherosclerotic plaques distributed in these arteries?

A

Focally distributed - governed by haemodynamic factors. For example, changes in flow/ turbulence (e.g. bifurcations)

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4
Q

What is neointima?

A

As the intima grows (new intima)

Changes in blood flow altering the phenotype of endothelial cells.

Altered gene expression in key; endothelial cells, smooth muscle cells, macrophages and fibroblasts

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5
Q

What makes up the structure of an atherosclerotic plaque?

A

Lipid
Necrotic core
Connective tissue
Fibrous cap
Lymphocytes

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6
Q

What are the 5 main stages of atherosclerosis progression over the course of the condition?

A

Fatty Streak
Intermediate Lesions
Fibrous Plaques (advanced lesions)
Plaque Rupture
Plaque Erosion

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7
Q

What is the fatty streak stage of atherosclerosis?

A

Earliest lesion of atherosclerosis < 10 years:

  • Scavenger receptors take up lipids in intima layer of vessel wall
  • Aggregations of lipid-laden macrophages (Foam Cells) and T lymphocytes within the intima layer of the vessel wall.
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8
Q

What is the intermediate lesion stage of atherosclerosis?

A

Lesion progresses to comprise layers of;

Foam cells
Vascular smooth muscle cells
T lymphocytes
Adhesion and aggregation of platelets to vessel walls
Extracellular Lipid Pools

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9
Q

What is the fibrous plaque stage of atherosclerosis?

A
  • Contains SMCs, macrophages, foam cell and T-lymphocytes
  • Covered by dense fibrous caps made of ECM proteins including; collagen (strength), elastin (flexibility) - these are laid down by SMCs
  • Impedes blood flow and prone to rupture
  • Often calcified
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10
Q

What is the plaque rupture stage of atherosclerosis?
Why might atherosclerotic plaques Rupture?

A
  • Plaque is constantly growing and receding - fibrous cap has to be resorbed and redeposited in order to be maintained
  • If balance shifted in favour inflammatory conditions (e.g. increased enzyme activity) the cap becomes weak and plaque ruptures.
  • Exposure of basement membrane, collagen, necrotic tissue and haemorrhage of vessels within plaque causes thrombus formation and vessel occlusion
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11
Q

What is the plaque erosion stage of atherosclerosis?

A
  • Small early lesions
  • Fibrous cap does not disrupt
  • Luminal surface underneath the clot may not have enough endothelium present but is smooth muscle rich
  • Prominent lipid core
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12
Q

What are the stages of atherosclerotic plaque formation?

A

1️⃣ Initiation of inflammation and endothelial cell dysfunction
2️⃣ Stimulus for adhesion of leukocytes - release of chemo-attractants
3️⃣ Dysfunctional endothelial cells allow the transmigration of LDLs into the tunica intima
4️⃣ Accumulation of LDLs tunica intima cause dysfuntional endothelial cells to release ROS and metalloproteases which function to oxidised the LDL → activated oxLDL
5️⃣ The activation of oxLDLs causes endothelial cells to express adhesion receptors for leukcocytes on their surface, leading to uptake of LDLs and monocytes
6️⃣ Surface of macrophages contain a scavenger receptor which facilitates the uptake of oxidised LDLs to form a foam cells
7️⃣ Foam cells have multiple pathophysiological functions:
- Release chemokines to attract more macrophages
- Release IGF-1 into tunica media to promote migration of SMCs (from media to intima) that increase collagen synthesis leading to the hardening of the atherosclerotic plaque
8️⃣ During this process, foam cells will die → releasing lipid content. This drives the growth of the plaque
9️⃣ Death of foam cells also causes release of contents which causes increased inflammation
🔟 T-cells also facilitate inflammation
🔟+ Excessive growth of the plaque causes it to rupture, leading to accumulation of the RBC, platelets and clotting factors → thrombosis

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13
Q

What initiates inflammation and leads to endothelial cell dysfunction in atherosclerosis?

A

Cholesterol/ high LDLs in the blood damages the endothelial cells
ROS from inflammation.

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14
Q

What chemo attractant is released by the endothelium and what does this lead to?

A

Selectins cause leukocyte rolling and firm adhesion to the blood vessel walls.

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15
Q

What are the pathological functions of a foam cell?

A

Release chemokines and attract further macrophages to the tunica intima

Release IGF-1 into the tunica media to promote migration of Smooth muscle cells from the tunica media into the tunica intima which increases the collagen synthesis and leads to the hardening of the atherosclerotic plaque.

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16
Q

What is a foam cell?

A

A macrophage that has been up take into the tunica intima that expresses scavenger receptors that will uptake oxidised LDLs

This uptake forms a foam cell.

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17
Q

What is a foam cell?

A

A macrophage that has been up take into the tunica intima that expresses scavenger receptors that will uptake oxidised LDLs

This uptake forms a foam cell.

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18
Q

What does the death of the foam cell release in atherosclerosis?

A

DNA material that attracts neutrophils
Proinflammatory cytokines
ROS
These all lead to increased inflammation.

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19
Q

What inflammatory cytokines are found in atherosclerotic plaques?

A
  • IL1, 6 and 8.
  • IFN-γ - strong proinflammatory cytokine
  • TGF-β - involves in wound healing
  • Chemokines (e.g. Monocyte Chemoattractant Protein-1)
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20
Q

How can Atherosclerosis (Coronary Heart Disease) be treated?

A

Percutaneous Coronary Intervention
Drugs

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21
Q

What is Percutaneous Coronary Intervention?

A

Non-surgical procedure that uses a catheter to place a stent into a narrowed blood vessel

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22
Q

What is Re-stenosis?

A

The recurrence of abnormal narrowing of an artery or valve after corrective therapy

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23
Q

What drugs are used to reduce restenosis in patients who have undergone corrective surgery?

A

Taxol and Sirolimus - work by reducing SMC proliferation after placement of stent. The stent is washed (eluted) with these drugs

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24
Q

How does Aspirin help to treat CHD?

A

Irreversible inhibitor of platelet cyclo-oxygenase to prevent Thromboxane A2 production and further platelet aggregation

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25
How does Clopidogrel/ Ticagrelor help to treat CHD?
Inhibitors of the stimulatory P2Y12 ADP receptor on platelets preventing platelet response amplification
26
How does Statins help to treat CHD?
Inhibit HMG CoA reductase - reduces cholesterol synthesis
27
What inflammation-causing cytokine is targeted using drugs alongside statin therapy?
IL-1
28
What drug therapy is used as an alternative to statins if ineffective or not tolerated?
PCSK9 inhibitors
29
Give some Non-modifiable risk factors for CVD and atherosclerosis?
Increased Age Family Hx Male
30
Give 5 Modifiable risk factors for atherosclerosis.
1. Smoking. 2. High levels of LDL's. 3. Obesity. 4. Low exercise 5. Diabetes. 6. Hypertension. 7. Alcohol consumption
31
Which histological layer of the artery may be thinned by an atheromatous plaque?
Tunica Media
32
What is the precursor for atherosclerosis.
Fatty streaks.
33
What are the functions of chemoattractants?
Chemoattractants signal to leukocytes. Leukocytes accumulate and migrate into vessel walls -> cytokine release e.g. IL-1, IL-6 -> inflammation!
34
Describe the process of leukocyte recruitment.
1. Capture. 2. Rolling. 3. Slow rolling. 4. Adhesion. 5. Trans-migration.
35
Define atherogenesis.
The development of an atherosclerotic plaque.
36
What are some end results of Atherosclerosis?
Angina Myocardial Infarction Transient Ischaemic Attacks Stroke Peripheral Vascular Disease Mesenteric Ischaemia
37
What is the key principle behind the pathogenesis of atherosclerosis?
It is an inflammatory process!
38
What is Primary and Secondary Prevention of CVD?
Primary Prevention – for patients that have never had cardiovascular disease in the past. Secondary Prevention – for patients that have had angina, myocardial infarction, TIA, stroke or peripheral vascular disease.
39
What is some advice for Primary and Secondary prevention of CVD?
Advice on diet, exercise and weight loss Stop smoking Stop drinking alcohol Tightly treat co-morbidities (such as diabetes)
40
What is the management for secondary prevention of CVD?
4 As: A – Aspirin (plus a second antiplatelet such as clopidogrel for 12 months) A – Atorvastatin 80mg A – Atenolol (or other beta-blocker – commonly bisoprolol) A – ACE inhibitor (commonly ramipril) titrated to maximum tolerated dose
41
What are Acute Coronary Syndromes?
Spectrum of acute cardiac conditions ranging from unstable angina to varying degrees of MI
42
What is the most common causes of Acute Coronary Syndromes?
Atherosclerotic rupture and consequential arterial thrombosis!
43
What is the mainstay treatment for ACS? why is this?
Anti-platelet medications: Aspirin Clopidogrel Ticagrelor Since a thrombus formed in a fast flowing artery are mostly made up of platelets.
44
Name some less common causes of Acute Coronary Syndromes?
Coronary vasospasm without plaque rupture Drug abuse (amphetamines, cocaine) Spontaneous Coronary Artery Dissection
45
What are the types of Acute Coronary Syndrome (ACS)?
Unstable Angina ST Elevation Myocardial Infarction (STEMI) Non-ST Elevation Myocardial Infarction (NSTEMI)
46
Explain how Spontaneous Coronary Artery Dissection can lead to Acute Coronary Syndrome?
tear in lining, lining comes away from the wall of the artery and blocks vessel.
47
Briefly describe the pathophysiology of ACS?
Atherosclerosis -> plaque rupture -> platelet aggregation -> thrombosis formation -> ischaemia -> hypoxia of cells -> angina infarction -> necrosis of cells -> permanent heart muscle damage and ACS.(MI)
48
How would you Diagnose someone presenting with ACS symptoms such as Chest pain?
ECG: If there is ST elevation or new left bundle branch block the diagnosis is STEMI. If there is no ST elevation then perform troponin blood tests: If there are raised troponin levels and other ECG changes (ST depression or T wave inversion or pathological Q waves) the diagnosis is NSTEMI If troponin levels are normal and the ECG does not show pathological changes the diagnosis is either: unstable angina Another cause such as musculoskeletal chest pain
49
What is Cardiac Troponin?
Protein complex functioning to regulate actin and myosin contraction
50
What would a rise in Troponin suggest?
Consistent with myocardial ischaemia as the proteins are released from the ischaemic muscle. However they are non specific so a raised troponin does not automatically mean ACS
51
Why is Cardiac Troponin relevant in diagnosing ACS?
Highly sensitive marker for cardiac muscle injury - increased levels is very indicative of myocardial cause
52
What is important to remember about Cardiac Troponin when being used for diagnosis?
not specific for ACS → also increases in conditions that causes stress in myocardium (e.g. PE, gram negative sepsis, myocarditis)
53
Give some other potential causes of raised troponins?
Chronic renal failure Sepsis Myocarditis Aortic dissection Pulmonary Embolism
54
What umbrella term does Stable Angina come under? What umbrella Term does Unstable Angina come under?
Ischaemic Heart Disease (IHD) Acute Coronary Syndrome (ACS)
55
Define angina.
Angina is a type of Ischaemic Heart Disease (IHD) characterised by chest pain It is an imbalance of O2 supply/demand mismatch to the heart due to reduced blood flow from a blockage
56
What is the most common cause of angina?
Narrowing of the coronary arteries due to atherosclerosis.
57
What are the different types of Angina Pectoris?
Stable Unstable Decubitus Crescendo Angina Prinzmetals's Vasospastic Microvascular Angina
58
What is Crescendo Angina?
patients present with angina over a period of months that gets progressively worse
59
What type of angina is associated with ACS?
Unstable Angina
60
Give 5 possible causes of angina.
1. Narrowed coronary artery = impairment of blood flow e.g. atherosclerosis. 2. Increased distal resistance = LV hypertrophy. 3. Reduced O2 carrying capacity e.g. anaemia. 4. Coronary artery spasm. 5. Thrombosis.
61
What is the prevalence of Angina in men and women?
Men - 5% (5000/100,000) Women - 4% (4000/100,000)
62
Give 5 modifiable risk factors for angina.
1. Smoking. 2. Diabetes. 3. High cholesterol (LDL). 4. Obesity/sedentary lifestyle. 5. Hypertension.
63
Give 3 non-modifiable risk factors for angina.
1. Increasing age. 2. Gender - Males 3. Family history/genetics.
64
What are the symptoms associated with ACS?
Central, Crushing chest pain associated with: Nausea and vomiting Sweating and clamminess Feeling of impending doom Shortness of breath Palpitations Pain radiating to jaw or arms
65
Briefly describe the pathophysiology of angina that results from atherosclerosis.
On exertion there is increased O2 demand. Coronary blood flow is obstructed by an atherosclerotic plaque -> myocardial ischaemia -> angina.
66
Briefly describe the pathophysiology of angina that results from anaemia.
On exertion there is increased O2 demand. In someone with anaemia there is reduced O2 transport -> myocardial ischaemia -> angina.
67
How do blood vessels try and compensate for increased myocardial demand during exercise.
When myocardial demand increases e.g. during exercise, microvascular resistance drops and flow increases!
68
Why are blood vessels unable to compensate for increased myocardial demand in someone with CV disease?
In CV disease: Epicardial resistance is high meaning microvascular resistance has to fall at rest to supply myocardial demand at rest. When this person exercises, the microvascular resistance can't drop anymore and flow can't increase to meet metabolic demand = angina!
69
What determines if Angina is stable?
Angina is stable if symptoms are always relieved by rest or GTN (glyceryl Trinitrate) spray.
70
What percentage of stenosis is associated with stable angina?
70% occlusion of the artery. This still allows enough blood flow through the artery at rest.
71
What is Stable angina?
Occlusion of an artery (70%) leading to ischaemia of the myocardial tissue resulting in chest pain. At rest enough blood can still flow through the artery to meet the demands of the tissue. Upon exercise or exertion, the tissue requires more oxygen and therefore a greater blood flow at which point the flow through the stenosed artery is not adequate enough and hence results in chest pain upon exertion.
72
what is the most common type of angina?
Stable angina
73
What is the most commonly affected region of the heart in stable angina?
Subendocardium. The coronary arteries struggle to perfuse the deeper layers of the myocardium either due to coronary artery stenosis or LV hypertrophy resulting in ischaemia to this portion of the tissue.
74
What are the Symptoms of angina?
Central Crushing chest Pain on exertion/rest /emotion/cold/heavy meals. May radiate to one or both arms, neck, jaws or teeth. Worsens with time Other Symptoms: Dyspnoea, nausea, sweatiness, faintness
75
What is the difference between symptoms of angina in Stable, unstable and decubitus types?
Stable angina occurs in periods of roughly 20 mins upon exertion or exercise. Unstable angina can be continuously painful at rest or even minimal exertion. Decubitus angina causes pain when lying down flat.
76
What is the difference pathophysiologically between stable and unstable angina?
Both are commonly caused by atherosclerotic plaque causing obstruction of a coronary artery. In unstable angina, the plaque may rupture causing blood to leak out and a secondary thrombus to form which occludes the artery further creating an even narrower lumen for blood to flow through.
77
What is a key distinction between angina and MI?
Angina results in pain due to myocardial ischaemia where the heart tissue is starved of oxygen but is still alive. MI is when the ischaemia has resulted in infarction that has led to the death of the heart tissue. Angina is therefore reversible and MI is not.
78
What is Prinzmetals Vasospastic angina?
angina where patients may or may not have atherosclerosis of the coronary vessels. instead ischaemia occurs due to vasospasms of the coronary arteries where they constrict so much they can cause ischaemia. These can occur at any time not just on rest or on exertion.
79
What is the mechanism that causes prinzmetals angina?
Not clearly understood but likely due to vasoconstriction factors such as Thromboxane A2 release
80
What layers of the heart are affected in Prinzmetals angina?
Transmural Ischaemia All layers of the heart wall supplied by the coronary arteries are affected.
81
What ECG reading would be shown on stable angina?
AT rest: Normal On exertion: ST segment depression due to subendocardium ischaemia.
82
What ECG reading would be shown in prinzmetals angina?
ST segment elevation due to transmural ischaemia.
83
How can symptoms of stable angina be relieved?
Relieved upon rest (after approx 5 mins) OR Symptoms relieved by GTN spray
84
Are troponin levels elevated in angina?
Often they are normal since the ischaemia has not killed the cells and thus the troponin have not been released sometimes they may be elevated
85
Describe the primary prevention of angina.
1. Risk factor modification. 2. Low dose aspirin.
86
Describe the secondary prevention of angina.
1. Risk factor modification. 2. Pharmacological therapies for symptom relief and to reduce the risk of CV events. 3. Interventional therapies e.g. PCI.
87
Name 3 symptom relieving pharmacological therapies that might be used in someone with angina.
1. Beta blockers. 2. Nitrates e.g. GTN spray. 3. Calcium channel blockers.
88
Describe the action of beta blockers.
Beta blockers are beta 1 specific. They antagonise sympathetic activation and so are negatively chronotropic and inotropic. Myocardial work is reduced and so is myocardial demand = symptom relief.
89
Give 4 side effects of beta blockers.
1. Bradycardia. 2. Tiredness. 3. Erectile dysfunction. 4. Cold peripheries.
90
When might beta blockers be contraindicated?
They might be contraindicated in someone with asthma or in someone who is bradycardic.
91
Give an example of a cardio-specific beta blocker
Atenolol
92
Describe the action of nitrates in GTN spray
Nitrates e.g. GTN spray are venodilators. Venodilators -> reduced venous return -> reduced pre-load -> reduced myocardial work and myocardial demand.
93
What is a common side effect of nitrates in GTN?
headache due to vasodilation
94
Describe the action of Ca2+ channel blockers.
Ca2+ blockers are arterodilators and negative Chronotropic/ionotropic agents: Reduced O2 demand -> reduced BP -> reduced afterload -> reduced myocardial demand.
95
What are some side effects of Calcium channel blockers?
postural hypotension Swollen ankles Flushing
96
Name 2 drugs that might be used in someone with angina or in someone at risk of angina to improve prognosis.
1. Aspirin. 2. Statins.
97
How does aspirin work?
Aspirin irreversibly inhibits COX. You get reduced TXA2 synthesis and so platelet aggregation is reduced. Caution: Gastric ulcers!
98
What are statins used for?
They reduce the amount of LDL in the blood.
99
What ECG reading would be shown on unstable angina?
May be normal May have some ST depression/T wave inversion
100
What ECG reading would be shown on unstable angina?
May be normal May have some ST depression/T wave inversion
101
What is the treatment for Stable angina?
Immediate Symptomatic Relief - GTN sublingual stray Long Term Symptomatic Relief - Beta Blocker (Atenolol) or Calcium Channel Blocker (Amlodipine) Secondary Prevention of CVD: Aspirin Atorvastatin ACE inhibitor Already on a beta blocker
102
What is the gold standard diagnostic investigation for Stable Angina?
CT Coronary Angiography
103
What is the diagnosis of stable angina?
ECG : Rest - normal Exertion - ST depression/Flat T waves CT Angiography - Stenosed atherosclerotic artery
104
What treatment should be considered for angina if pharmacology is unsuccessful?
Referral for revascularisation Through PCI or CABG
105
What is revascularisation?
Revascularisation might be used in someone with angina. It restores the patent coronary artery and increases blood flow.
106
Name 2 types of revascularisation.
1. PCI. 2. CABG.
107
What procedures may be involved in PCI?
Balloon Stent Angioplasty with Stent
108
Give 2 advantages and 1 disadvantage of PCI.
1. Less invasive. 2. Convenient and acceptable. 3. High risk of restenosis.
109
Give 1 advantage and 2 disadvantages of CABG.
1. Good prognosis after surgery. 2. Very invasive. 3. Long recovery time.
110
How is unstable angina diagnosed?
History ECG - may present as ST-segment depression, transient ST-segment elevation, or T-wave inversion No elevation in troponin - unstable angina not associated with damage to the heart
111
What is the Clinical Classification of Unstable Angina?
- Cardiac chest pain at rest or during minimal exertion - Severe and of new onset cardiac chest pain - Cardiac chest pain with crescendo pattern (distinctly more severe, prolonged, or frequent than before)
112
What are the types of MI?
Non-ST Elevated Myocardial Infarction (NSTEMI) ST Elevated Myocardial Infarction (STEMI) Silent MI
113
What would the ECG for a STEMI look like?
ST segment elevation in local leads May have Q waves (Pathological after some time)
114
What would the ECG for a NSTEMI look like?
ST depression T wave inversion No Q waves
115
What is the difference in an NSTEMI and STEMI when caused by atherosclerosis?
NSTEMI occurs after a partial occlusion of major Coronary artery STEMI occurs after complete occlusion of a major Coronary artery.
116
What is the acute treatment for ACS?
MONAC: Morphine Oxygen (if Sats < 94%) Nitrates (GTN) Aspirin (300mg) Clopidogrel (dual antiplatelet)
117
What is the treatment for an NSTEMI following acute treatment of ACS?
GRACE score: low risk - monitor Med-High risk - angiogram / PCI
118
What is the treatment of choice for STEMI?
PCI
119
What is the long term treatment/Secondary prevention management following ACS?
6 As Aspirin (75g once daily) Another antiplatelet - Ticagrelor/Clopidogrel Atorvastatin (80mg once dail) ACE inhibitors (ramipril) Atenolol (or another bB) Aldosterone antagonist (spironolactone) in those with clinical heart failure
120
What is Dressler's Syndrome?
Post myocardial infarction syndrome. Localised immune response causing pericarditis.
121
What are the complications of MI?
DREAD: Death Rupture of the heart septum/papillary muscles Edema (causing heart failure) Arrythmia and Aneurysm Dressler's Syndrome
122
What heart area and ECG leads correspond to: Left Coronary Artery LAD Circumflex Right Coronary Artery
Left Coronary Artery: Heart area - Anterolateral ECG leads - I, aVL, V3-V6 LAD: Heart area - Anterior ECG leads - V1-4 Circumflex: Heart area - Lateral ECG leads - I aVL, V5-6 Right Coronary Artery: Heart area - Inferior ECG leads - II, III, aVF
123
What is the Epidemiology for an MI?
600/100,000 for men. 200/100,000 for women
124
Name some of the function of platelets during arterial thrombosis
- Procoagulant activity; release of *thrombin* - Dense granule secretion; contributes to platelet activation - Alpha granule secretion; contributes to coagulation and inflammation - Platelet-fibrin clot; fibrin acts as glue that keeps the thrombus growing and allow it block of arteries to cause MI.
125
Give a brief overview of the process by which platelets cause the platelet plug?
(1) Shear flow (2) Initial adhesion GPIb/VWF (3) Rolling GPIb/VWF/α2β1/collagen (4) Stable adhesion activation/aggregation GPVI, GPIIb/IIIa (5) Platelets are activated by ADP (vai P2Y12R), causing them to change shape, aggregate and seal off the endothelial breach
126
What combined therapy is used to manage patients with ACS?
Aspirin, P2Y12 Inhibitors and GPIIb/IIIa antagonists
127
Give some examples of P2Y12 inhibitors?
Clopidogrel Ticagrelor Prasugrel
128
What is a major side effect of P2Y12 inhibitors?
Increases risk of bleeding! Serious bleeding must subside prior to administration and risk of thrombosis vs. risk of bleeding must be monitored throughout use.
129
Why are GPIIb/IIIa Antagonists very useful in STEMI pateints undergoing PCI?
Cover for delayed absorption of oral P2Y12 Inhibitors occuring due to opiates delaying gastric emptying
130
What is the role of anticoagulants used in the treatment of ACS?
Targets formation and/or activity of thrombin; inhibiting both fibrin formation and platelet activation
131
What anticoagulant is commony used during Non-STEMI ACS?
Fondaparinux (a pentasaccharide) is used prior to coronary angiography
132
What anticoagulants are used during PCI?
Full Dose: Heparin (unfractionated or LMWH) Bivalirudin
133
What is a Silent MI?
When a diabetic patient may not experience typical chest pain during an acute coronary syndrome
134
Name some causes of oxygen supply reduction associated with IHD?
- Common: anaemia and hypoxaemia - Uncommon: polycythemia, hypothermia, hypovolaemia, hypervolaemia
135
Name some causes of oxygen demand increase associated with IHD?
- Common: hypertension, tachyarrhythmia, valvular heart disease - Uncommon: hyperthyroidism, hypertrophic cardiomyopathy
136
Name some environmental causes of Angina?
Emotional stress Large meals Cold weather
137
Give some predisposing factors associated with IHD?
- Age - Smoking - Family history - Diabetes mellitus - Hyperlipidemia - Hypertension - Kidney disease - Obesity - Physical inactivity - Stress
138
What are the three major physiological factors lending to oxygen mismatch associated with IHD?
- Impairment of blood flow by proximal arterial stenosis (e.g. atherosclerosis) - Increased distal resistance (e.g. left ventricular hypertrophy) - Reduced oxygen carrying capacity of blood (e.g. anaemia)
139
What is Ohms Law?
Flow = Change in pressure / Resistance
140
What is Poiseuille's Equation?
Q = R^4
141
What is Poiseuille's Law?
Change in pressure = 8luQ/pi r^4 l - length of vessel U - viscosity Q - flow R - radius of vessel
142
How does Poiseuille's Law relate to CCS?
Relationship between flow, pressure and resistance; combination of Ohm's law and vessel resistance equation. Radius has to fall below 75% before symptoms
143
How would you discuss a patients pain when taking a history for IHD?
OPQRST: - Onset - Position (site) - Quality (nature/ character) - heavy, central, tight - Relationship - associated with SOB, exertion, posture, meals - Radiation - to arms, jaw, neck - Relieving/ aggravating factors - Severity - Timing - Treatment - if use GTN spray, ascertain if it helps!
144
What characteristics of chest pain suggest ischaemic cardiac pain?
- Heavy, tight pain - Located centrally - Provoked by cold weather, big meals, exertion - Relieved by rest, GTN spray - Associated SOB
145
What is exercise testing?
Patient undertakes mild exercise on a treadmill and ECG is run simultaneously - any abnormailites, refer patient to catheterisation lab
146
What is a Perfusion/ Myoview scan?
IV radio-labelled agent travels to the coronary arteries - areas of darkness signify a blockage.
147
What are Psychosocial factors?
Factors influencing psychological responses (cognitive; behavioural; emotional) to the social environment and pathophysiological changes
148
What is a Coronary Prone Behaviour Pattern?
Coronary prone behaviour is the collection of behaviours and attitudes associated with heart disorders especially coronary heart disease and cardiovascular disorders.
149
Give some examples of personality trains associated with Coronary Prone Behaviour Patterns?
- Aggressiveness/Anger (biggest risk factor) - Ambition - Competitiveness - Hostility (biggest risk factor) - Impatience - Sense of time urgency - Need for achievement
150
What causes the first and Second Heart Sound?
First - Mitral Valve closure Second - Aortic Valve Closure
151
What is the cause for the 3rd heart sound?
early-diastolic rapid distension of the left ventricle that accompanies rapid ventricular filling and abrupt deceleration of the atrioventricular blood flow
152
What is the cause for the 4th Heart Sound?
the result of vibrations generated within the ventricle.
153
Give some psychosocial factors that increase the risk for CHD?
Depression and Anxiety Low quantity and quality of social support High demanding jobs/low control of jobs
154
What are the layers of the pericardium?
Outer Fibrous layer - Continuous with the central tendon of the Diaphragm Serous layer: Outer Parietal - lines the inner surface of the fibrous pericardium Inner Visceral - forms the outer layer of the heart (Epicardium)
155
What is found between the parietal and Visceral pericardium? What is the Function of this?
Pericardial cavity: Contains 50ml of serous fluid to minimise the friction generated when the heart contracts
156
Which great vessels are Contained within the pericardium?
Roots of the great vessels: Aortal Pulmonary Artery Pulmonary Veins SVC IVC
157
What are the main functions of the pericardium?
- **Fixes the heart** in the mediastinum and limits its motion. - **Prevents overfilling** of the heart. The relatively inextensible fibrous layer of the pericardium limits the filling pressure and volume of the heart - **Lubrication**. A thin film of fluid between the two layers of the serous pericardium reduces the friction generated by the heart as it moves within the thoracic cavity - **Protection from infection**. The fibrous pericardium serves as a physical barrier between the muscular body of the heart and adjacent organs prone to infection, such as the lungs.
158
What is the purpose of the small reserve volume associated with the pericardial sac?
Volume of pericardial fluid changes based on the physiological state of the heart.
159
What is Cardiac Tamponade?
Reduction in cardiac output due to a raised intrapericardial pressure secondary to a pericardial effusion. As there is a greater pressure, the heart chambers cannot expand during diastole reducing SV and CO
160
What is Beck's Triad?
Three clinical signs associated with pericardial tamponade: - Hypotension (weak pulse or narrow pulse pressure) - Muffled heart sounds - Raised jugular venous pressure.
161
What are some signs associated with cardiac tamponade?
Beck's Triad Pulsus Paradoxus Tachycardia
162
What is Pulsus Paradoxus?
An inspiratory decrease in systolic BP >10mmHg. (not a paradox but exaggeration of normal physiology) Paradox: On physical exam, beats are detected on cardiac auscultation during inspiration which cannot be palpated at the radial pulse. This is associated with increased JVP (kussmauls sign)
163
How is cardiac tamponade diagnosed?
ECHO - diagnostic ECG - varying QRS peaks CXR - big globular heart
164
How is Cardiac Tamponade treated?
Urgent pericardiocentesis
165
Define Pericardial Effusion?
Accumulation of excess fluid in the pericardial cavity; the pericardial fluid contains blood components such as fibrin, RBCs and WBCs
166
What is the main cause of pericardial effusion?
Typically pericarditis RF are all factors related to pericarditis
167
How is Pericardial Effusion treated?
treat underlying cause NSAIDS Colchicine
168
What is Chronic pericardial effusion?
Slow accumulation of fluid allowing for adaptation of the parietal pericardium
169
Why does Chronic Pericardial Effusion rarely cause Cardiac Tamponade?
Increased compliance reduces the effect on diastolic filling and therefore slow accumulating effusion does not often cause tamponade.
170
Define Acute Pericarditis?
Inflammation of the pericardium commonly due to viral infection.
171
What are the different types of Pericarditis?
Acute Chronic effusive Chronic Constrictive
172
What is Constrictive Pericarditis?
Calcification thickens the pericardium and affects cardiac function
173
Who is typically affected by pericarditis?
Males - 20-50yrs
174
What is the Pathology of Pericarditis?
inflammation narrows the pericardial space causing the inflamed layers to rub against each other and cause further inflammation. Extra fluid may be produced to compensate causing effusive pericarditis
175
What is the Pathology of Pericarditis?
inflammation narrows the pericardial space causing the inflamed layers to rub against each other and cause further inflammation. Extra fluid may be produced to compensate causing a pericardial effusion. If this fluid accumlation impacts the hearts function this is cardiac tamponade
176
What is the most common cause of Pericarditis?
Viral infection
177
What is the Most common Infectious, Non infectious and Iatrogenic cause of pericarditis?
Infectious - Viral Non infectious - Neoplastic (secondary metastatic tumours) Iatrogenic - direct injury from PCI/radiofrequency ablation
178
What is the Most common Infectious, Non infectious and Iatrogenic cause of pericarditis?
Infectious - Viral Non infectious - Neoplastic (secondary metastatic tumours) Iatrogenic - direct injury from PCI/radiofrequency ablation
179
What are some of the main causes of pericarditis?
Infection - Coxsackie Virus Dressler's Syndrome Autoimmune Neoplastic Metabolic Traumatic Iatrogenic - PCI
180
What are some infectious causes of pericarditis?
HEAP: Herpes virus Enterovirus (Coxsackie) Adenovirus Parovirus
181
What are some Autoimmune causes of Pericarditis?
Sjogren's Syndrome Rheumatoid Arthritis Scleroderma Systemic Vasculitides
182
How is Pericarditis diagnosed?
ECG: Widespread saddle shaped ST elevation PR depression ECHO - exclude pericardial effusion/tamponade FBC - increased WCC Chest Pain ESR/CRP - High ESR may suggest aetiology Pericardial Rub
183
What is Pericardial Rub?
Extra heart sound heard upon auscultation One systolic - Two diastolic Sound resembles scratching.
184
What are the signs of effusion associated with pericarditis?
Pulsus paradoxus Kussmaul's Sign - rise in JVP on inspiration
185
What are the symptoms of pericarditis?
Severe pleuritic chest pain Dyspnoea Cough Systemic disturbance - weight loss, joint pain
186
What is the nature of the chest pain associated with pericarditis?
Sharp severe pleuritic chest pain - radiate to left shoulder due to phrenic nerve Pain is relieved when sitting forward Pain is exacerbated when lying flat or on inspiration
187
What are some important differential diagnoses of pericarditis?
MI - has no pericardial rub/not related to lying down (ST elevation not saddle shaped) pneumonia Aortic Dissection PE
188
What is the management for pericarditis?
Period of sedentary activity until resolution of inflammation NSAIDS (2 weeks) Cochicine (3 weeks) Consider Abx for bacterial aetiology
189
What are some complications of pericarditis?
Pericardial effusion - cardiac tamponade myocarditis constrictive pericarditis
190
How is cardiac tamponade diagnosed?
ECHO - diagnostic ECG - varying QRS peaks CXR - big globular heart
191
What is cardiomyopathy?
A disease of the heart muscle tissue where there is impaired ability to contract and/or there is electrical conduction dysfunction.
192
What are the 3 major determinants of myocardial performance?
Preload - the volume of blood entering the ventricles that causes a greater stretch on the ventricles. Afterload - The pressure that must be overcome in order to eject blood from the ventricles during systole. Contractility
193
What are the main types of cardiomyopathy?
Hypertrophic Cardiomyopathy (HCM) Dilated Cardiomyopathy (DCM) Arrhythmogenic Right/Left ventricular Cardiomyopathy (ARVC/ALVC) Restrictive Cardiomyopathy.
194
What is the most common type of Cardiomyopathy?
Dilated Cardiomyopathy
195
What is Primary Cardiomyopathy?
Occurs when genes encoding proteins involved in the Myocardial tissue are dysfunctional resulting in poor/altered function myocardial cells and further pathology.
196
What is Secondary Cardiomyopathy?
Where the Myocardial cells structure and function becomes damaged through: Toxins inflammation infection systemic disorders
197
How are cardiomyopathies diagnosed?
ECHO Some with MRI Troponins may be elevated.
198
What is Dilated Cardiomyopathy?
Dilation of the ventricles (chamber enlargement) causing weakness of the ventricular myocardial cells impairing their contractility and hence their systolic function leading to poorly ejected blood.
199
What are the Symptoms of Dilated Cardiomyopathy?
Can be Asymptomatic May present as congestive heart failure. Dyspnoea Weakness Fatigue Oedema Raised JVP Pulmonary congestion Cardiomegaly 3rd/4th Heart Sounds
200
What is the Aetiology of Dilated Cardiomyopathy?
Gene mutations often in cytoskeletal genes. Ischaemia Alcoholism Thyrotoxicosis
201
What is the epidemiology of DCM?
More common in males 35/100,000 Median age - 50
202
How is DCM diagnosed?
ECHO - Marked Dilatation CXR - Cardiomegaly, pulmonary oedema ECG - May have tachycardia
203
What is the treatment for DCM?
Tx of underlying conditions - AF/ HF Bed rest Loop and Thiazide Diuretics for fluid overload ACEi Beta Blockers
204
What is Hypertrophic Cardiomyopathy (HCM)?
Unexplained primary cardiac hypertrophy (often on LV wall and interventricular septum) leading to impaired diastolic filling and a reduced stroke volume. due to thick heart and reduced compliance
205
What is the cause of HCM?
Autosomal Dominant mutation in Sarcomeric genes: Beta-myosin heavy chain Troponin T alpha tropomyosin.
206
What are the symptoms of HCM?
Most may be asymptomatic Variable dyspnoea Chest pain / palpitations Syncope Sudden death
207
What are the main complications of DCM?
Progressive Heart Failure Sudden Cardiac Death
208
What may be found upon examination of a patient with HCM?
Forceful Apex beat Late ejection systolic Murmur Jerky Carotid pulse Alpha wave in JVP.
209
What is the Epidemiology of HCM?
1/500 Men and black people more likely
210
What is the most common form of sudden cardiac death in the young population and atheletes?
Hypertrophic Cardiomyopathy
211
How is HCM diagnosed?
ECG - LVH, ST segment changes, T wave inversion CXR - variable, left atrial enlargement
212
What is the treatment of HCM?
Amiodarone - reduce risk of arrythmias and sudden death Treat chest pain: Beta blockers and CCB - Verapamil Implantable cardioverter defibrillator
213
What is a severe complication of HCM?
Sudden Death
214
What is Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)?
Associated with Desmosome gene mutations Fibro-fatty replacement of the RV myocytes leading to impaired ability of RV muscle to contract due to muscle cell loss.
215
What is Naxos disease?
A autosomal recessive genetic condition associated with ARVC and diffuse palmoplantar keratoderma and woolly hair
216
What are the symptoms of ARVC?
Palpitations Presyncope/syncope Death possible on first presentation
217
What is the most common sustained arrythmia in HCM?
Atrial Fibrillation
218
What is the cause of ARVC?
Unknown but may be due to apoptosis, inflammation or genetics
219
What is the Epidemiology of ARVC?
1/2000 Mainly affects males 30-50% of cases have autosomal dominant genetic predisposition
220
How is ARVC diagnosed?
ECHO - RV wall Dimensions and abnormalities RV angiography MRI - fatty infiltration and fibrosis on RV wall.
221
How is ARVC treated?
Standard heart failure medication. Beta blockers in asymptomatic patients. Heart transplant/
222
What is the most frequent cause of heart transplants?
Dilated cardiomyopathy.
223
What is Restrictive cardiomyopathy?
Rigid Fibrotic Myocardium Increased myocardial stiffness despite normal LV cavity size and function. Increased stiffness restricts diastolic filling as the ventricle is incompliant.
224
What are the causes of Restrictive cardiomyopathy?
infiltrative myocardial disease Granulomatous disease - Amyloid heart disease, Sarcoidosis.
225
What is the epidemiology of Restrictive cardiomyopathy?
between 1/1000 to 1/1500 5% of all cardiomyopathies Mainly affects the elderly, tropical Africa
226
What are the symptoms of restrictive cardiomyopathy?
Heart failure with normal systolic function Dyspnoea Fatigue S3 and S4 heart sound pulmonary oedema Murmurs Features of RV failure
227
What is the diagnosis of restrictive cardiomyopathy?
ECHO - thickened ventricular walls, valves and atrial septum. MRI - to distinguish between cardiomyopathies.
228
What is the Treatment for restrictive cardiomyopathy?
None Consider transplant
229
What are the complications of restrictive cardiomyopathy?
Heart failure sudden death Poor prognosis.
230
What is the main feature of ARVC?
Arrhythmia
231
What do all cardiomyopathies carry a risk of?
Developing arrythmia
232
What is a channelopathy?
Gene mutations in genes that are involved in ion channel proteins resulting in channelopathies.
233
What can be a cardiovascular sign of channelopathies?
Arrythmias
234
Give some examples of cardiac Channelopathies
Long QT Short QT Brugada Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT)
235
What is the major clinical sign of ARVC?
Ventricular Tachycardia
236
What is the commonest symptoms of channelopathies?
Recurrent Syncope
237
What is Brugada Syndrome?
A channelopathy caused by a mutation in the cardiac sodium channel gene
238
What are the symptoms of Brugada Syndrome?
Asymptomatic May have syncope Can cause sudden death
239
What are the common rhythmic abnormalities associated with Brugada Syndrome?
Ventricular fibrillation Polymorphic Ventricular Tachycardia
240
What would the ECG look like with a patient with Brugada?
Characteristic ST elevation in chest leads.
241
What is sudden cardiac death in young people often due to?
Inherited condition likely a cardiomyopathy or channelopathy
242
What conditions are included in Aortovascular syndromes?
Marfans Vascular Ehler Danlos (EDS) Loeys-Dietz
243
What is Diastolic Distensibility?
The pressure required to fill the ventricle to the same diastolic volume
244
What are the Consequences of Hypertension?
Stroke (ischaemic and haemorrhagic) Myocardial Infarction Heart failure Chronic renal disease Cognitive decline Premature death
245
What are the different stages of clinical Hypertension?
- Define Stage 1 Hypertension. Clinical = 140/90 Ambulatory = 135/85 - Define Stage 2 Hypertension Clinical = 160/100 Ambulatory = 150/95 - Define severe Hypertension. Clinical = 180/110
246
How is Hypertension treated?
Lifestyle modification Antihypertensive drug therapy
247
Who should be offered antihypertensive drug treatment for hypertension?
Individuals aged 80 or below and individuals who have one or more of the following: - Target organ damage - Established CVD - Renal disease - Diabetes - 10-year CVD risk of >20%
248
Describe mechanisms of BP control - targets for therapy
- Cardiac output and peripheral resistance - Interplay between the RAAS and sympathetic nervous system (NA) - Local vascular vasoconstrictor and vasodilator mediators
249
Describe the renin angiotensin-aldosterone system.
1. Kidneys sense low BP and renin is released from juxtaglomerular cells. 2. Renin converts angiotensinogen to angiotensin I 3. ACE from the lungs converts angiotensin I to angiotensin II 4. Angiotensin II (extremely potent vasoconstrictor) stimulates aldosterone release resulting in increased Na+ and thus water reabsorption which leads to increased blood volume and thus blood pressure
250
Describe the Sympathetic nervous system response to a drop in BP?
Drop in BP results in the release of noradrenaline, leading to vasoconstriction and increased contractility of the heart thus increasing peripheral resistance and cardiac output and thus BP. Also results in renin release which further augments RAAS
251
What is the MOA of ACE inhibitors?
Prevent ACE converting angiotensin I to Angiotensin II and therefore inhibiting the CVS effects of Angiotensin II
252
Give examples of ACEis?
- Ramipril - Enalapril - Perindopril - Trandolapril
253
What are the indications for ACE Inhibitors?
- Hypertension - Heart Failure - Diabetic nephropathy
254
What are the main Adverse effects of ACEi?
Related to reduced Angiotensin II: Hypotension Acute renal failure Hyperkalaemia Teratogenic effects in pregnancy Related to increased Kinin Production: Cough Rash Anaphylactoid reactions
255
Why are there side effects such as cough when using ACEi?
ACE breaks down bradykinin. If ACE is inhibited then bradykinin levels increase This can cause a persistent dry cough
256
What are Angiotensin II Receptor Blockers (ARBs)?
They block the receptors of angiotensin II preventing its binding and it inducing effects.
257
Give examples of ARBs?
- Candesartan - Losartan - Valsartan - Telmisartan
258
What are the indications for ARBs?
- Hypertension (and when ACEi is contradicted due to cough) - Diabetic nephropathy - Heart failure (when ACEi contraindicated - acts on AT-1 receptor)
259
What are the ADRs associated with ARBs?
- Symptomatic hypotension (esp. in volume depleted patients) - Hyperkalaemia - Potential renal dysfunction - Rash - Angiooedema - Teratogenic in pregnancy
260
What are Calcium Channel Blockers (CCBs)?
These block the calcium channels from allowing Ca entry into cardiomyocytes.
261
What are the indications for CCBs?
- Hypertension - IHD (angina) - Arrhythmias
262
Give examples of CCBs.
- *Dihydropyridines (e.g.* amlodopine, nifedipine, felodipine) - *Phenylalkylamines* (e.g. verapamil) - *Benzothiozepines* (e.g. diltiazem)
263
Give an example and explain the actions of Dihydropyridines?
Amlodipine: Preferentially affect Vascular smooth muscle and act as peripheral arterial vasodilators
264
Give an example and explain the actions of Phenylalkylamines?
Verapamil: Directly affects the heart - negatively chronotropic, negatively ionotropic
265
Give an example and explain the actions of Benzothiozepines?
Diltiazem: Intermediate heart and peripheral vascular effects
266
What are the ADRs associated with CCBs?
Due to peripheral vasodilation (Dihydropyridines): - Flushing - Headache - Peripheral oedema - Palpitations Due to negative chrontropic effect (Phenylalkylamines and Benzothiozepines): - Bradycardia - Atrioventricular block - Postural hypotension Due to negative ionotropic effect (Benzothiozepines) - Worsening of HF Verapamil causes constipation
267
What are Beta Blockers?
Beta adrenoceptor blockers that prevent the effects of adrenaline and noradrenaline in the sympathetic nervous system. They work on B1 and B2 receptors.
268
Give examples of Beta Blockers?
- Bisoprolol - Propranolol - Atenolol - Carvedilol
269
What are the indications for beta blockers?
- IHD - angina - HF - Arrhythmia - Hypertension
270
Which beta blockers are B-1 selective?
Metoprolol Bisoprolol (Atenolol is mostly B1 but not entirely cardioselective)
271
Which beta blockers are non-selective?
Propranolol Nadolol Carvedilol
272
What condition is contraindicative for beta blockers?
Asthma
273
What are the ADRS associated with Beta blockers?
- Fatigue - Headache - Sleep disturbance - Bradycardia - Hypotension - Cold peripheries - Erectile dysfunction
274
What conditions can Beta blockers cause exacerbations of
Asthma PVD - Claudication or Raynauds Heart Failure - when given in standard doses or acutely
275
How do Diuretics reduce blood pressure?
Increased excretion of water, salt and metabolites in urine
276
What are the indictations for Diuretics?
- Hypertension - Heart failure
277
What are the different classes of Diuretics?
Thiazide diuretics - act on distal tubule blocking Na/Cl exchanger Loop diuretics - act on ascending loop of henle, blocks Na/K/2Cl (NKCC2) transporter Potassium-sparing diuretics (Aldosterone antagonists) - Retain Potassium
278
Give examples of Diuretics of each class?
- Thiazide diuretics: bendroflumethiazide, hydrochlorothiazide - Loop diuretics: furosemide, bumetanide - Potassium-sparing diuretics: spironolactone, eplerenone
279
What are the ADRs associated with Diuretic?
- Hypovolaemia (mainly loop) - Hypotension (mainly loop) - Hypokalaemia - Hyponatraemia - Hypomagnesaemia - Hypocalcaemia - Hyperuricaemia (gout) - Erectile dysfunction (thiazides) - Impaired glucose tolerance (thiazides)
280
Give an alpha 1 adrenoceptor blocker used as an anti-hypertensive?
Doxazosin
281
Give examples of centrally acting antihypertensives?
Act on the CNS: Moxonidine Methyldopa
282
When may Methyldopa be used?
During pregnancy for gestational hypertension
283
Give an example of a direct Renin Inhibitor?
Aliskiren
284
Outline the treatment programme for hypertension of someone under the age of 55yrs?
First line: ACEi or ARB Second Line: ACEi/ARB + CCB Third Line: ACEi/ARB + CCB + Thiazide Fourth line (Resistance HTN): Consider addition of Spironolactone, alpha blocker, beta blocker
285
Outline the treatment programme for hypertension of someone over the age of 55yrs or afro-caribbean ?
First line: CCB Second Line: ACEi/ARB + CCB Third Line: ACEi/ARB + CCB + Thiazide Fourth line (Resistance HTN): Consider addition of Spironolactone, alpha blocker, beta blocker
286
Define Heart Failure?
Complex clinical syndrome of signs and symptoms that suggest the efficiency of the heart as a pump is impaired.
287
What are the different Types of Heart Failure?
Left Ventricular Systolic Dysfunction (Most common) - caused by contractility dysfunction Heart failure with preserved ejection fraction (HFPEF) - caused by dysfunction during diastole (filling) Acute/Chronic Heart Failure
288
What is the underlying principle of treatment of heart failure?
Vasodilator therapy via neurohumoral blockade (RAAS-SNS)
289
What is used in the symptomatic treatment of heart failure?
Diuretics - often loop
290
What are the stages involved in disease influencing neurohumoral blockade therapy?
A (first Line) - ACEi + BB therapy (low dose titrated up slowly) B: Aldosterone Antagonist (Spironolactone) C: ARNI (ARB + Neprilysin inhibitor) - Entresto ( combination of Valsartan + Sacubitril) D: SGLT2 inhibitor - Dapagliflozin E: ACEi intolerance - ARB F: ACEi and ARB intolerance - Hydralazine/nitrate combination G: consider Digoxin
291
What are Nitrates when used as a treatment?
Arterial and Venous dilators These reduce both preload (venous dilation) and afterload (arterial dilation) to lower the BP
292
What are the main indications for nitrates?
IHD (Angina) Heart Failure
293
Give Examples of nitrates?
- Isosorbide mononitrate (tablet) - GTN spray - GTN infusion (acute/ severe angina)
294
What are the ADRs associated with Nitrates?
- Headache - GTN spray syncope - Potential tolerance to the drug
295
What are the cardiac natriuretic peptides (CNPs?)
Atrial Naturetic Peptide (ANP) - Atria Brain Naturetic Peptide (BNP) - Brain and Ventricles
296
What causes the physiological release of cardiac natriuretic peptides?
Stretching of atrial and ventricular muscle cells, raised atrial or ventricular pressures and volume overload
297
What effect do CNPs have on renal excretion?
Increases renal excretion of sodium (natriuresis) and water (diuresis)
298
What effect do CNPs have on vascular smooth muscle?
Relax vascular smooth muscle (except efferent arteriole) of renal glomeruli to preserve filtration pressure in kidney whilst still removing Na+ and thus water thus no renal damage)
299
What effect do CNPs have on vascular permeability?
Increased vascular permeability
300
What effect do CNPs on the release of other chemical mediators?
Reduces aldosterone, angiotensin II, endothelin (most potent vasoconstrictor) and ADH release
301
What are CNPs a counter-regulatory system to?
Counter-regulatory system to the renin-angiotensin system
302
What are NPs metabolised by?
NEP or Neprilysin
303
How can the inhibition of NP metabolism be used for in the treatment of HF?
NEP inhibition increases levels of natriuretic peptides
304
Name examples of NEP inhibitors.
Sacubitril - is a neprilysin inhibitor Entresto (ARNI) - is a combination of sacubitril and valsartan (ARB) - VERY EFFECTIVE IN HEART FAILURE
305
What are the Class I antiarrhythmic Drugs?
Sodium Channel Blockers: 1A: quinidine 1B: lidocaine 1C: flecainide
306
What are the Class II Anti-arrhythmics?
Beta-blockers: - non-selective (e.g.propranolol, nadolol, carvedilol) - beta-1 selective (e.g. bisoprolol, metoprolol)
307
Why Is Propranolol useful for arrhythmias immediately post MI?
It blocks both Beta adrenoceptors and can block sodium channels too
308
What are the Class III Anti-arrhythmics?
Prolongs action potential: Amiodarone blocks potassium channels during repolarisation to increase the AP. *Cause QT prolongation; potential for significant side effects in patient with QT prolongation*
309
What are the Class IV Anti-arrhythmics?
Calcium channel blockers (only phenylalkylamines and benzothiozepines): Verapamil and Diltiazem Verapamil is more effective than amlodipine as it does not affect calcium channel at rest
310
What do Class I and III anti-arrythmics do?
Rhythm control (sympathetic drive, e.g. adrenaline worsens arrhythmias)
311
What do Class II and IV anti-arrythmics do?
Rate control (sympathetic drive, e.g. adrenaline worsens arrhythmias)
312
What are the ADRs associated with Amiodarone?
- Bradycardia - Interstitial Lung Disease - Thyroid (hyper and hypo) - Corneal (ocular)/cutaneous (skin) - Hepatic dysfunction/hypotension when IV (due to solvents) - Photosensitivity - Drug interactions
313
What type of drug is Digoxin?
Cardiac glycoside
314
By what mechanism does Digoxin affect the heart?
Inhibits Na/K pump; Therefore Na/Ca exchanger is not active as Na conc increases in the cell Therefore Ca is not removed from the cell causes an increase in Ca2+ inside the cells of the heart Increases contraction of myocytes
315
What affect does Digoxin have on the heart?
- Bradycardia (increased vagal tone) - Slows AV conduction (increased vagal tone) - Increased ectopic activity - Increased force of contraction (direct +ve inotropic effect) by increasing intracellular calcium
316
What are the indications for Digoxin?
- Atrial Fibrillation; reduces ventricular rate response - Severe heart failure; has a positive inotropic effect
317
What are the ADRs of Digoxin?
- Narrow therapeutic range - Nausea - Vomiting - Diarrhoea - Confusion
318
What are Structural Heart defects?
These are often Congenital defects that occur during pregnancy to the heart that are not necessarily inherited that cause heart problems. They can range from minor to life incompatible
319
Give examples of some structural heart defects?
Artial Septal Defect (ASD) Ventricular Septal Defect (VSD) Coarctation of the Aorta Bicuspid Aortic Valve Fallot's Tetralogy Patent Ductus Arteriosus Patent Foramen Ovale
320
What is Tetralogy of Fallot?
Combination of four congenital abnormalities affecting the structure of the heart. This causes oxygen-deficient blood to flow out of the heart and to the rest of the body.
321
What are the four abnormalities associated with Tetralogy of Fallot?
Ventricular Septal Defect (VSD) - hole between 2 ventricles Over-riding Aorta - Allows blood from both ventricles to entre the aorta RV Hypertrophy - thickening of RV muscle Pulmonary Stenosis - Narrowing of the exit from the RV to pulmonary circulation
322
What are the consequences of the abnormalities in Tetralogy of Fallot?
There is a greater pressure in the RV than the LV and so blood is shunted into the LV → cyanosis as blood is not oxygenated
323
What are the symptoms associated with Tetralogy of Fallot?
Severity dependent on degree of pulmonary stenosis Cyanosis Systolic Murmur Increase Hb concentration
324
What is the cause of Tetralogy of Fallot?
Unknown but likely genetic influence
325
What is the Epidemiology of Tetralogy of Fallot?
Most common complex cardiac abnormality. 10% of congenital heart conditions
326
What are the investigations for Tetralogy of Fallot?
CXR - boot shaped heart ECHO CG - anatomy and degree of stenosis
327
What is the Treatment for Tetralogy of Fallot?
Early surgical intervention within 2 years
328
What is Ventricular Septal Defect (VSD)?
An abnormal connection between the LV and RV causing a left to right shunt enabling more blood to enter the pulmonary circulation.
329
Why is there not cyanosis in VSD?
There is a higher pressure in the LV than the RV and so blood is shunted from the left to right meaning there is an increased amount of blood going to the lungs; not cyanotic.
330
What are the clinical signs of a VSD?
Size Matters: Small - Asymptomatic Large - Exercise intolerance, failure to thrive, murmur
331
What is the epidemiology of VSD?
25% of congenital abnormalities 2/1000
332
What are the treatments for VSD?
May close on its own Surgical repair
333
What is the pathology of Eisenmenger's Syndrome?
High pressure pulmonary blood flow leads to damage in pulmonary vasculature → increased resistance to blood flow (pulmonary hypertension) → RV pressure increases → shunt direction reverses (RV to LV) → cyanosis
334
What condition often leads to Eisenmenger's Syndrome as a complication?
VSD
335
What are the risks associated with Eisenmenger's syndrome?
- Stroke - Endocarditis - Risk of death
336
What is Atrial Septal Defect (ASD)?
A common structural defect where there is a hole in the septum between the 2 atria
337
What are the types of ASD?
Ostium Primum - associated with AV valve abnormalities Ostium Secundum (85% of ASD) - Asymptomatic
338
What is the pathophysiology of ASD?
There is a higher pressure in the LA than the RA and so blood is shunted from the left to right; not cyanotic. This may be reverse if Eisenmenger's Syndrome develops
339
What are the clinical signs of a large ASD?
Pulmonary ejection systolic and mid systolic murmur -Significant increase in blood flow through the right heart and lungs Enlarged pulmonary arteries. Right heart dilatation - can lead to RHS failure SOB on exercise Increased chest infection.
340
How are ASDs treated?
Surgical Repair Percutaneous repair
341
What are Atrio-Ventricular Septal Defects (AVSD)?
A hole between the atria and the ventricles 2 per 10,000 Strong association with Downs
342
What are the symptoms of AVSD?
Breathlessness Poor feeding Poor weight gain
343
What are the clinical signs of a large AVSD?
- Enlargement of the heart - Heart failure - inability to adequately supply body oxygen - Eisenmenger's Syndrome - Exercise intolerance - Pulmonary hypertension - Pneumonia
344
What is Patent Ductus Arteriosus (PDA)?
Ductus arteriosus fails to close after birth; allows abnormal transmission of blood from the aorta to the pulmonary artery. Pulmonary arterial and left atrial flow increase
345
What are the symptoms of PDA?
- Pulmonary hypertension and RHF (due to Eisenmenger's reaction) - Breathlessness - Poor feeding, failure to thrive - Risk of endocarditis
346
What are the clinical signs of PDA?
- Tachycardia - Machine murmur - Enlarged heart - breathlessness - Eisenmenger's Syndrome
347
What is Coarctation of the Aorta?
Narrowing of the Aorta Excessive sclerosing that normally closes the ductus arteriosus extends into the aortic wall leading to narrowing of the aorta distal to the ductus arteriosus
348
What is the result of a Coarctation of the aorta on body perfusion?
Blood is diverted massively through the aortic arch branches and therefore you have increased perfusion to the upper body and less to the lower body.
349
How is Coarctation of the Aorta Diagnosed?
CXR - notched ribs CT angiogram
350
What are the Clinical signs of Coarctation of the Aorta?
Right arm Hypertension (may have left arm hypotension) Lowe pressure in vessels distal to Coarctation Bruits (buzzes) over the scapulae and back Murmur
351
What is a Patent Foramen Ovale?
Failure of the foramen ovale to close after birth
352
What are the effects of a patent foramen Ovale?
No symptoms If no other abnormalities then normal health
353
What percentage of people may have a patent foramen ovale?
1/4
354
What is a bicuspid aortic valve?
Aortic valve has 2 cusps rather than 3. Get turbulence generation instead of laminar flow in the aorta
355
What are the issues with a bicuspid aortic valve?
Can work well at birth and go unoticed Exercise exacerbates complications Abnormal degradation of the aortic valve over time - requires valve replacement
356
What is the epidemiology of a bicuspid aortic valve?
1-2% of general Population.
357
What is a common complication of bicuspid aortic valves?
Aortic Aneurysm development
358
What is the most common inherited heart defect?
Bicuspid Aortic Valve
359
Which structural heart abnormalities are not cyanotic and why?
VSD ASD PDA Left to right shunt
360
Which structural heart abnormalities are cyanotic and why?
Tetralogy of Fallot Right to left shunt.
361
What is pulmonary stenosis?
Narrowing of the outflow tracts of the right ventricles This results in increased resistance of the pulmonary circulation leading to RV hypertrophy
362
What are the categories for Hypertension?
Normotensive Stage 1 Hypertension Stage 2 Hypertension Severe Hypertension (Stage 3)
363
What is the normal range for blood pressure?
90/60 - <120/ <80
364
Define stage 1 hypertension
- ABP 135/85 - Clinic 140/90
365
Define Stage 2 Hypertension?
- ABP 150/95 - Clinic 160/100
366
Define severe hypertension
Clinic 180/120
367
What is Primary Hypertension?
When it is Idiopathic (no known cause) 95% of cases
368
What is Secondary Hypertension?
When the underlying cause is known 5% of cases
369
What are some underlying causes of secondary hypertension?
CKD - as a result of diabetic nephropathy Endocrine - Phaeochromocytoma, Cushings, Conns Iatrogenic Pregnancy
370
What are the risk factors of hypertension?
Increased Age Blacker ethnicity Overweight - biggest RF Decreased exercise/sedentary lifestyle smoking diabetes stress increased salt intake Family Hx
371
What is the most common cause of secondary hypertension?
CKD as a result of diabetic nephropathy
372
Define malignant hypertension
Rapid rise in blood pressure which damages vasculature Pathological hallmark is fibrinoid necrosis Usually with severe hypertension + bilateral retinal haemorrhages and exudates
373
When is hypertension an emergency?
When there is sign of immediate damage: Papilloedema Acute kidney injury Acute stroke ACS Aortic dissection
374
What is the pathogenesis of Hypertension?
All mechanisms where there is increased CO from Increased RAAS and SNS activity. Mechanisms where there is increased TPR will increase BP
375
What is the equation for BP?
BP = CO x TPR
376
What are the vascular causes of Secondary Hypertension?
CKD OSA Glomerulonephritis - increased renin Renal Artery stenosis - increase renin
377
What are the endocrine causes of Hypertension?
Phaeochromocytoma Cushings Conns (hyperaldosteronism) Acromegaly Thyroid Dysfunction
378
What are some autoimmune causes of Hypertension?
Lupus Scleroderma
379
What are the symptoms of Hypertension?
Mostly Asymptomatic May have a pulsatile headache (but no more than general population) Found on screening
380
When should you screen to find the cause of a patients hypertension?
Early onset (<30yrs) with no risk factors Hypertension resistant to 3 drugs Malignant hypertension If patient has other specific symptoms indicative of secondary causes
381
What drugs can increase blood pressure?
NSAIDS SNRis Corticosteroids Oestrogen contraceptives Stimulants Anti-anxiety drugs (gabapentin) Anti-TNFs
382
Which investigations are ordered to quantify overall risk in patients with hypertension?
Fasting glucose Cholesterol
383
How is Hypertension diagnosed?
BP reading in hospital of 140/90 + Then ABPm for 24 hours to confirm diagnosis (BP 135/85 + throughout day) Assess end organ damage
384
What investigations are used to assess end organ damage in Hypertension?
ECG/ECHO - LV Hypertrophy Fundoscopy - papilloderma U&Es - hypokalaemia in Conns Urinalysis, Proteinuria and Haematouria Serum creatine GLucose Renal function
385
What is the lifestyle management of Hypertension?
Stop Smoking Exercise - lose weight Control diet
386
What are the main drugs used to lower blood pressure?
CCBs ACEi/ARBs Diuretics B-blockers
387
What is the medical management of hypertension in a patient who is <55yrs old or has T2DM?
1st Line - ACEi/ (ARB if ACEi are Contraindicated) 2nd Line - ACEi/ (ARB if ACEi is CI) + CCB 3rd Line - ACEi/ (ARB if ACEi is CI) + CCB + Thiazide 4th Line (resistant HTN) - ACEi/ (ARB if ACEi is CI) + CCB + Thiazide + 4th drug: 4th drug if K+ > 4.5 = alpha/beta blocker 4th drug if K+ < 4.5 = Spironolactone
388
What is the Medical Management for a Patient with HTN who is >55+yrs old or from Afro-caribeean origins?
1st Line - CCB 2nd Line - ACEi/ (ARB if ACEi is CI) + CCB 3rd Line - ACEi/ (ARB if ACEi is CI) + CCB + Thiazide 4th Line (resistant HTN) - ACEi/ (ARB if ACEi is CI) + CCB + Thiazide + 4th drug: 4th drug if K+ > 4.5 = alpha/beta blocker 4th drug if K+ < 4.5 = Spironolactone
389
If a patient is Black, over 55yrs old and has T2DM which medical management line of HTN would you use?
T2DM takes precedence and Therefore first line is ACEi
390
What are the possible complications of hypertension?
Chronic heart disease MI Stroke - Common complication Heart failure Peripheral arterial damage Aortic aneurysm Chronic kidney disease Vascular dementia
391
When should hypertension treatment be withheld?
When patients are undergoing general anaethesia
392
What is the monitoring for hypertension?
Renal function impairement Otherwise, no monitoring as concordance with treatment an issue Evidence shows going off medication causes hypertension to return
393
What are the thresholds for treatment of hypertension?
Low risk patients - 160/100 High risk patients (diabetes, sign of end organ damage, risk of coronary events) - 140/90
394
What is aortic Stenosis?
Narrowing of the aortic valve
395
What is the basic overlying pathogenesis of valvular stenosis?
Stiff/thick valve leaflets Obstructs forward flow leads to systemic or pulmonary congestion Stenotic Valve on RHS = Systemic Venous Congestion Stenotic Valve on LHS = Pulmonary Venous Congestion
396
What valves are often affected by valvular stenosis?
Mitral Aortic Pulmonary Tricuspid
397
What would a regurgitant valve cause?
Causes insufficiency and proximal chamber dilation. This is due to loss of structural chamber integrity and strength
398
What is a regurgitant valve?
Poorly sealed valve leaflets Defective and floppy backflow of the blood through thte valve (incompetance) Valvular Regurgitation on RHS = Systemic Venous congestion Valvular Regurgitation on LHS = Pulmonary Venous congestion
399
What occurs as a result of stenosis?
Increased upstream pressure resulting in proximal chamber dilation and hypertrophy This leads to the heart becoming large and rigid and poorly compliant
400
What is the difference between a regurgitant valve and a stenotic valve?
Regurgitant - Defective and floppy Stenotic - Narrowed valve lumen
401
Which valve defects commonly cause murmurs?
Aortic Regurgitant and stenosis Mitral Regurgitant and stenosis
402
Where are Right sided defects commonly heart as murmurs?
RILE (Right = inspiration and Left = Expiration) Pulmonary/Tricuspid on RHS on insipration
403
Where are Left sided defects commonly heard as murmurs?
RILE (Right = inspiration and Left = Expiration) Aortic/Mitral heard on LHS on Expiration
404
What is the nmeonic for when you would hear aortic regurgitance/stenosis and mitral valve reguritance and stenosis?
ARMS (Aortic regurgitance / Mitral Stenosis) on Diastolic ASMR (Aortic Stenosis / Mitral Regurgitance) on Systolic
405
What is the main cause of Mitral Valve Stenosis?
Rheumatic Heart disease (Most common - post strep pyogenes infection)
406
What are some less common causes of Mitral Valve Stenosis?
Valve calcification Infective endocarditis
407
What is the pathology of Mitral Valve Stenosis?
RHD causes mitral reactive inflammation Over years this is exacerbated w/ calcification results in LA hypertrophy and chamber dilation. Raised LA pressure - causes pulmonary hypertension RV hypertrophy and failure
408
What are the symptoms of Mitral Valve Stenosis?
Malar Flushed Cheeks - due to low CO2 Pulmonary HTN - Dyspnoea A wave on JVP Loud S1 Snap - due to thickend valve cusps Low pitched MID-DIASTOLIC murmur - loudest at apex and expiration when Px lies on LHS
409
What murmur is heard in Mitral Valve Stenosis?
Low pitched - due to decreased pulse and decreased CO MID DIASTOLIC Murmur Loudest at APEX Best heard on EXPIRATION when Px is lying on LHS
410
What is the Diagnosis/investigations for Mitral valve stenosis?
CXR - LA enlarged ECG - Afib, M shaped P waves due to LA enlarged GS - ECHO - Assess valve area
411
What is the Treatment for Mitral Valve Stenosis?
Diuretics - Furosemide Rate control Anticoagulants Surgical: Percutaneous balloon Valvotomy - Stent opening mitral valve Mitral valve replacement
412
What is the main cause of Mitral Valve Regurgitation?
Myxomatous Mitral Valve Connective tissue disorders - Marfans, Ehlers Danlos Infective Endocarditis
413
What are the risk factors for Mitral Valve Regurgiation?
Females Increased Age Low BMI Prior MI or Connective Tissue disorder
414
What are the symptoms of Mitral Valve Regurgitation?
Exertion Dyspnoea - due to Pulmn HTN from backlogged blood Murmur - PAN SYSTOLIC BLOWING MURMUR
415
What is the pathogenesis of Mitral Valve regurgitation?
Mitral valve fails to prevent reflux of blood into LA Increased LA pressure increased pulmonary pressure Pulmonary Oedema
416
What is the Murmur Like in Mitral Valve Regurgitation?
PAN SYSTOLIC BLOWING murmur RADIATES to AXILLA Loudest at APEX Soft S1 and Prominent S3 in heart failure (severe cases)
417
What is the diagnostic investigations for mitral valve regurgitation?
Gold standard = ECHO - LA size and LV function analysis ECG CXR
418
What is the second most common valvular condition requiring surgery?
Mitral Valve Regurgitation
419
How is Mitral Valve Regurgitation Treated?
ACEi + beta blockers Serial ECHO Monitoring If severe (Sx at rest) then Valve repair/replacement
420
What is the normal area of the aortic valve?
3-4cm^2
421
What is the lumen size of the aortic valve when you get symptoms?
1/4 of the lumen size
422
What is the most common valve disorder?
Aortic Stenosis
423
What are the consequences of Aortic Valve Stenosis?
LV dilation and hypertrophy
424
What are the causes of Aortic Stenosis?
Congenital Bicuspic valve <70yrs Calcification due to Age >70yrs Rheumatic Valvular Disease
425
What are the 3 types of aortic valve stenosis?
Supravalvular SubValvular Valvular
426
What is the pathogenesis of Aortic Valve stenosis?
Ageing leads to aortic valve thickening and clacifications obstructing the normal LV outflow. Increased afterload Leads to increased LV pressure and compensatory LV hypertrophy. May lead to relative ischaemia causing angina arrhythmia and LV failure
427
What are the symptoms of aortic valve stenosis?
SAD: Syncope (exertional) Angina Dyspnoea - related to HF Murmur - EJECTION SYSTOLIC CRESCENDO DECRESCENDO
428
What is the Murmur like in aortic valve stenosis?
Ejection Systolic Crescendo Decrescendo Radiates to CAROTIDS At Right sternal Boarder - 2nd IC space Prominent S4 seen in LVH Narrow pulse presssure
429
What is the diagnostic investigations for aortic valve stenosis?
ECHO - LV size and function, aortic valve area (doppler derived gradient) ECG - LVH CXR
430
What is the treatment for Aortic Valve stenosis?
Surgical Tx if symptomatic: Healthy Px - Open repair/replacement More at risk (>75yrs) TAVI - transcutaneous valve implant
431
What are the main causes of Aortic valve regurgitation?
Congenital Bicuspid Valve RHD Connective tissue disorders - Marfans, Ehlers Danlos
432
What is the pathophysiology of Aortic Regurgitation?
Leakage of blood back into the LV during diastole due to ineffective closure of the cusps LV dilation and hypertrophy to maintain CO Reduced diastolic BP Relative ischaemia Leads to LV failure
433
What are the signs and symptoms of Aortic Reguritation?
Signs: Quincke - nailbed pulases when pressed De Musset - Head bobbing signs Wide pulse pressure LV failure Early Diastolic Murmur Austin Flint Murmur (severe) Symptoms: Angina Dyspnoea - on exertion
434
What is the murmur like in Aortic Regurgitation?
EARLY DIASTOLIC BLOWING murmur At RIGHT Sternal boarder - 2nd IC space Austin Flint murmur (severe)
435
What is the Diagnostic investigations for Aortic Regurgitation?
ECHO - Evaluate Aortic valve root and dimensions ECG CXR
436
What are the treatments for Aortic Regurgitation?
Consider Infective endocarditis prophylaxis - Also considered as a DDx Vasodilators (ACEi to improve SV and reduce regurgitance if Px is asymptomatic or HTN) Surgical Valve replacement if symptomatic
437
What is Infective Endocarditis?
Infection of the heart valves or other endocardial lined structure within the heart (e.g. septal defects, pacemaker leads, surgical patches)
438
What are the different types of Infective Endocarditis?
Left-sided Native (mitral or aortic) Left-sided Prosthetic (early - within a year, late - after a year) Right-sided IE (rarely prosthetic). Device related (e.g. pacemakers, defibrillators)
439
How does the nature of Infective Endocarditis affect the outcome?
Left-sided; are more likely to cause thrombo-emboli systematically. Right-side more likely to spread to cause a pulmonary embolism
440
What are the Causes of Infective Endocarditis?
Bacteria: S.aureus (most common in IVDU, T2DM, surgery) S. Viridans P.aeruginosa S.bovis HACEK Organisms
441
What are the risk factors for Infective Endocarditis?
Male, Elderly, Prosthetic Valves Young IV Drug user Young w/Congenital heart defect Rheumatic Heart Disease
442
Where does Infective endocarditis usually affect? When may it affect other regions?
Usually Mitral valve (LHS) In IVDU it will more commonly affect Tricuspid Valve (RHS)
443
What is the Pathogenesis of Infective Endocarditis?
Abnormal/damaged endocardium leads to increased platelet deposition. Bacteria virulence factors can adhere to this Vegetation Propagation involves activation of clotting cascade Inhabiting MOs cause cardiac valve distortion and cardiac failure + sepsis Typically around the valves
444
What is a common consequence of Infective Endocarditis?
Valvular Regurgitation Than can lead to Ventricular insufficiency and subsequent increased risk of HF
445
What are the symptoms of Infective Endocarditis?
Fever + Non-specific Symptoms New valve regurgitation Sepsis Emboli of unknown origin
446
What are the specific signs of infective endocarditis?
OSLER NODES - Finger nodules JANEWAY LESIONS - Painful marks on hands SPLINTER HAEMORRHAGES - on finger nails ROTH SPOTS - Retinal Haemorrhage
447
What are the diagnostic investigations for infective endocarditis?
Made using DUKE CRITERIA - 2 major or 1 major + 2 minor: Major: Positive blood culture with typical IE microorganism Echocardiograph showing endocardial involvement (e.g. vegetation, abcess) or new valvular regurgitation. Minor: Fever (>38) Pre-disposing factor (e.g. predisposing heart condition, IV drug user) Vascular phenomena (e.g. major arterial emboli, septic pulmonary infarcts, intracranial haemorrage, Janeway lesions, conjunctival haemorrhage) Immunological problems (e.g. glomerulonephritis, Osler's nodes, Roth's spots, rheumatoid factor) Microbiological evidence (e.g. positive blood culture (non-IE typical microorganism) or serological evidence of infection with organism consistent with IE)
448
What are the two main sites vegetation adheres to in IE?
Atrial surface of AV valves Ventricular surface of SL valves.
449
What is the Treatment for Infective Endocarditis?
S.aureus - Vancomycin + rifampicin ( +gentamycin if prosthetic valve) S.viridans - Benzypenicillin + gentamycin for 4-6 weeks Surgery - remove valve if incompetent and replace with prosthetic
450
What are the complications of infective endocarditis?
Heart failure Aortic root abscess Septic emboli Sepsis
451
Define Heart Failure
Inability of the heart to deliver blood thus oxygen that is commensurate with the requirement of the metabolising tissues despite normal or increased cardiac filling
452
How is HF categories by the New York Heart Association (NYHA)?
- Class I - no limitation (asymptomatic) - Class II - slight limitation (mild HF) - Class III - marked limitation (symptomatically moderate HF) - Class IV - inability to carry out any physical activity without discomfort (symptomatically severe HF)
453
What is the median age for Heart Failure?
80-years-old (men; 78, women; 82)
454
What is Ejection Fraction?
Measurement, expressed as a percentage, of how much blood the left ventricle pumps out with each contraction
455
What is the normal range for Ejection Fraction?
65-75%
456
What are the 2 main pathologies of heart failure?
Systolic Heart failure - blood cant be pumped out of the LV well enough Diastolic Heart Failure - Not enough blood fills the ventricles during diastole In both cases blood builds up in the lungs causing congestion and fluid build up.2
457
What are the different types of Heart Failure?
HF-Reduced Ejection Factor (Left Ventricular Ejection Factor <40%) HF-Preserved Ejection Factor (Left Ventricular Ejection Factor >50% with dilated LA(>34ml/m2 AND and LVH) HF-Pulmonary Hypertension (Pulmonary Artery Pressure >40mmHg) HF-Valve (stenosis or regurgitation)
458
What is the most common aetiology of Heart Failure?
Myocardial dysfunction resulting from IHD
459
Name some other common causes of Heart Failure.
Hypertension Ischaemic Heart Disease Alcohol excess Cardiomyopathy Valvular disease - Aortic Stenosis, Mitral Regurgitation Arrythmias - Atrial Fibrillation Endocarditis Pericarditis
460
What ejection fraction would suggest borderline HF and Systolic HF?
Borderline - 40-50% Systolic HF - <40%
461
What is the difference between left and right heart failure?
Left heart failure would cause congestion in the pulmonary circulation. Right heart failure would cause congestion in the systemic circulation Both can affect each other - eg. RHS HF can cause LHS HF
462
What are the main causes of Systolic heart failure?
Ischaemic heart disease - myocardial damage/infarction can lead to scarring which doesnt contract and so the EF is reduced Chronic hypertension - increased afterload causes LV hypertrophy. This increases the O2 demand, and squeezes coronary arteries decreasing O2 supply to the myocardium. Overtime the heart muscle fatigues and becomes inefficient at pumping blood. Dilated cardiomyopathy - chamber grows and there is increases preload leading to increased contraction strength temporarily. over time the muscle walls get thinner and will end up becoming inefficient
463
What are the main causes of Diastolic heart Failure?
Chronic Hypertension can also cause diastolic failure by increasing hypertrophy of LV wall. This then decreases volume of the ventricle leading to a reduced filling room and reduced preload. Aortic stenosis and hypertrophic cardiomyopathy follows the same pattern as chronic hypertension as there is increased afterload and increased LV hypertrophy Restrictive cardiomyopathy - less compliant LV walls due to increased stiffness. therefore the walls cannot stretch when filling leading to reduced preload
464
What are the symptoms of Heart failure?
Breathlessness (dyspnoea) Cough Orthopnoea - SOB on lying flat - relieved by standing (causes crackles on auscultation) Paroxysmal Nocturnal Dyspnoea Peripheral Oedema
465
What is Paroxysmal Nocturnal Dyspnoea?
Paroxysmal nocturnal dyspnoea is a term used to describe the experience that patients have of suddenly waking at night with a severe attack of shortness of breath and cough.
466
How is Heart Failure diagnosed?
Clinical presentation BNP blood test (specifically “N-terminal pro-B-type natriuretic peptide” – NT‑proBNP) ECG - ascertain underlying cause - ischaemia, LVH, HTN, Arrhythmia Echocardiogram - Ascertain underlying cause CXR - (ABCDE) Alveolar oedema, Kerley Blue lines, Cardiomegaly, Dilated Upper lobe vessels, Plural Effusions
467
What are the key signs of Heart Failure?
- Tachycardia and hypotension - Shortness of Breath - Fatigue - Displaced apex beat - Raised JVP - common in RHF - Additional heart sounds/ murmurs, - Hepatomegaly (e.g. pulsatile/ tender) - RHF - Peripheral/ sacral oedema - Ascites
468
What are some Risk Factors of Heart Failure?
Anything that increases myocardial work: - Age over 65 years - Men (due to lack of oestrogen protection) - Obesity - African descent - Individuals who have had an MI - Alcohol excess - Hyperthyroidism - Anaemia - Pregnancy
469
What lifestyle changes are recommended as a treatment for Heart Failure?
- Avoid large meals - Weight loss - Smoking cessation - Exercise - Vaccination
470
What is the first line medical management for Heart Failure?
ABAL: ACEi - Ramipril (ARBs if ACEi contraindicated) Beta blockers - Bisoprolol Aldosterone Antagonists - Spironolactone, Eplerenone Loop Diuretics - Furosemide
471
What is Cor Pulmonale?
Right sided Heart failure caused by respiratory disease.
472
What is the pathogenesis of Cor Pulmonale?
The increased pressure and resistance in the pulmonary arteries (pulmonary hypertension) results in the right ventricle being unable to effectively pump blood out of the ventricle and into the pulmonary arteries. Causes RV Hypertrophy and overtime this will become inefficient leading to HF. This leads to back pressure of blood in the right atrium, the vena cava and the systemic venous system.
473
What are some common respiratory causes of Cor Pulmonale?
COPD is the most common cause Pulmonary Embolism Interstitial Lung Disease Cystic Fibrosis Primary Pulmonary Hypertension
474
How do patients with Cor Pulmonale Present?
Early Cor pulmonale - Asymptomatic Later: SOB Peripheral Oedema Dyspnoea - on exertion Syncope Chest Pain
475
What are the signs of Cor Pulmonale?
Hypoxia Cyanosis Raised JVP (due to a back-log of blood in the jugular veins) Peripheral oedema Third heart sound Murmurs (e.g. pan-systolic in tricuspid regurgitation) Hepatomegaly due to back pressure in the hepatic vein (pulsatile in tricuspid regurgitation)
476
What is the Management of Cor Pulmonale?
Treat symptoms and underlying cause. Long term oxygen therapy may be used.
477
What are some end results of Atherosclerosis?
Angina Myocardial Infarction Transient Ischaemic Attacks Stroke Peripheral Vascular Disease Mesenteric Ischaemia
478
What is Peripheral Vascular Disease?
Narrowing of arteries distal to the aortic arch
479
What is the Pathogenesis of Peripheral Vascular Disease?
Intermittent Claudication: Atherosclerosis causing stenosis of arteries and partial lumen occlusion - pain on exertion. Critical Limb Ischaemia: Severe occlusion of arteries and blood supply is barely adequate to meet metabolic demand leading to pain at rest and increased risk of gangrene and infection.
480
What are the symptoms of Peripheral Vascular Disease?
Varying symptoms: Asymptomatic ABPI (ankle brachial Pressure index) <0.9 Bruits (pulsatile regions due to turbulent blood flow) Intermittent claudication (pain on exercise) Rest pain (critical limb ischaemia) Skin ulceration and gangrene.
481
What are some Signs of Peripheral Vascular Disease?
Signs: Absent femoral, popliteal or foot pulses. Cold white legs.
482
What can be a complication of acute limb ischaemia?
Complete occlusion of the vessel - due to embolic/thrombotic event. Causes 6 Ps
483
What are the 6Ps of acute complete limb Ischaemia?
Pulselessness Pallor Pain Perishingly Cold Paralysis Paraesthesia
484
What is the Fontane classification of PVD?
1. Asymptomatic 2. Intermittent Claudication (pain on exertion) 3. Chronic Limb Ischaemia (pain at rest) 4. Ischaemic ulcers - Gangrene
485
What is the diagnosis of PVD?
ABPI: 0.5 - 0.9 = Intermitted Claudication <0.5 = Chronic Limb Ischaemia Colour Doppler ultrasound - confirm site and degree of stenosis. CT angiography if surgery considered.
486
What is ABPI and what is the normal range?
Compares Blood in post/ant. tibial artery to brachial artery. 0.9-1.3 = normal
487
What is ABPI and what is the normal range?
Compares Blood in post/ant. tibial artery to brachial artery. 0.9-1.3 = normal
488
What is the treatment for PVD?
Intermittent Claudication - RF management Chronic Limb Ischaemia - Revascularisation surgery (PCI/Bypass graft) In Ischaemic limb emergency - PCI within 4-6 hours otherwise amputation.
489
What are the Risk Factors for Peripheral Vascular Disease?
Smoking Hypertension Ageing Obesity CKD T2DM
490
What are the main complications of PVD?
Amputation Permanent limb weakness Rhabdomyolysis Increased risk of CVD.
491
What are the types of aneurysms?
True - weakening of arterial wall leading to dilation False Mycotic
492
What is an Abdominal Aortic Aneurysm?
Permanent dilation of the aorta exceeding 50% where >3cm diameter. Often Infra-renal (below renal arteries)
493
What are the Risk factors of AAA?
Idiopathic, Smoking, obesity, HTN, Family Hx Connective tissue disorders - Marfans, Ehlers Danlos
494
What is the Pathogenesis of AAA?
Smooth muscle, elastic and structural degradation of the vascular wall in ALL 3 LAYERS of the vascular tunic. Increased Leukocyte infiltration leads to increased vessel diameter to > 3cm +
495
What diameter of an AAA is at increased risk of rupture?
AAA more than 5.5cm diameter
496
What happens if the AAA ruptures?
Medical Emergency requires immediate surgical repair 80% mortality prior to reaching hospital.
497
What are the symptoms of an Unruptured AAA?
Usually asymptomatic
498
What are the symptoms of a ruptured AAA?
Sudden epigastric pain, Radiating to flank Pulsatile mass in abdomen Hypotensive and Tachycardic
499
What is a differential Diagnosis of a ruptured AAA?
Acute pancreatitis. Does not tend to have a pulsatile feel.
500
What is the diagnostic investigation of AAA?
Abdominal Duplex Ultrasound If ruptured then none - medical Emergency
501
What is the Treatment of an AAA?
Unruptured - manage RF ASx and <5.5cm - monitor Sx and>5.5 - surgery (endovascular repair or open surgery)
502
What is the Treatment of a Ruptured AAA?
Stabilise ABCDE + fluids AAA Graft surgery repair.
503
What is the incidence of an AAA?
25/100,000 incidence at 50yrs. Rises with age. Males
504
What is an Aortic Dissection?
Tear in the intima resulting in blood dissecting through the tunica media causing separation of the layers of the aortic wall.
505
What are causes of Aortic Dissection?
Genetic link, Atherosclerosis, Inflammatory, Trauma: Mechanical stress causes a tear in the intima of the aortic lining. This causes blood to enter the aortic wall under pressure causing a haematoma and separates the layers.
506
What are the risk factors for Aortic Dissection
Connective tissue disorders - Marfans, Ehlers Danlos Hypertension Cocaine Use Aortic Aneurysm Smoking Hypercholesterolaemia
507
What are the most common locations of an Aortic Dissection?
Sinotubular junction - Aortic root near aortic valve Just distal to Left Subclavian Artery (descending thoracic aorta)
508
What are the symptoms of Aortic Dissection?
Phase 1: Initial event; severe 'ripping' pain and pulse loss. The bleeding then stops. Diastolic murmur Phase 2: Pressure builds, and causes a rupture, either into pericardium (tamponade), mediastinum or pleural space. Pain often migrates as dissection progresses.
509
What is the Diagnosis of Aortic Dissection?
Transoesophageal ECHO OR CT angiogram (if Px is haemodynamically stable) Shows intimal Flap and False lumen CXR - Shows widened mediastinum
510
What are the treatments for Aortic Dissection?
Surgical: Open repair/Endovascular aortic repair Medication (to reduced HR and BP): Special Beta Blockers - Esmolol Vasodilator - Sodium Nitroprusside
511
What are some complications of Aortic Dissection?
Cardiac Tamponade Aortic Insufficiency Pre renal AKI Stroke - Ischaemic
512
What is an Arrhythmia?
An abnormal electrical conduction in the heart causing a beat disturbance.
513
Define tachycardia.
> 100 bpm.
514
Define bradycardia.
< 60 bpm.
515
Give 3 potential consequences of arrhythmia.
1. Sudden death. 2. Syncope. 3. Dizziness. 4. Palpitations. 5. Can also be asymptomatic.
516
Give the two broad categories of tachycardia.
1. Supra-ventricular tachycardia's. 2. Ventricular tachycardia's.
517
Where do supra-ventricular tachycardia's arise from?
They arise from the atria or atrio-ventricular junction.
518
Do supra-ventricular tachycardia's have narrow or broad QRS complexes?
Supraventricular tachycardias are often associated with narrow complexes.
519
Name 5 supra-ventricular tachycardia's.
1. Atrial fibrillation. 2. Atrial flutter. 3. AV node re-entry tachycardia (AVNRT) - Most common SVT 4. Accessory pathway - Wolfson Parkinson White 5. Focal atrial tachycardia. (sinus Tachycardia)
520
Where do ventricular tachycardia's arise from?
The ventricles.
521
Do ventricular tachycardia's have narrow or broad QRS complexes?
Ventricular tachycardias are often associated with broad complexes.
522
Name 2 Ventricular Tachycardias?
Ventricular Tachycardia Ventricular Fibrillation
523
Name 3 arrhythmias that come under Bradycardia rhythms?
RBBB / LBBB 1, 2, 3 Heart Block Sinus Bradycardia
524
What is atrial Fibrillation?
Irregularly irregular atrial firing Rhythm
525
What are the causes of AF?
Heart Failure HTN secondary to mitral valve stenosis Idopathic
526
What are the risk factors for AF?
60+ T2DM HTN Valve defects Hx of MI
527
What is the pathogenesis of AF?
Rapid re-entrant ectopic foci (300-600 Bpm) Causes atrial spasm Causes atrial blood to pool and therefore reduces CO and increases risk of thromboembolic events.
528
What are the symptoms of AF?
1. Palpitations. 2. Shortness of breath. 3. Fatigue. 4. Chest pain. 5. Increased risk of thromboembolism and therefore stroke.
529
What are the different types of AF?
Paroxysmal (episodic) Persistent (longer than 7 days) Permanent (sinus Rhythm unrestorable)
530
What is the diagnosis of AF?
ECG is diagnostic Irregularly Irregular pulse w/ narrow QRSs <120ms No P waves (fibrillatory squiggles)
531
What is the Treatment of AF?
1. Rate control - beta blockers, CCB and digoxin. 2. Rhythm control - electrical cardioversion or pharmacological cardioversion using flecainide. 3. Flecainide can be taken on a PRN basis in people with infrequent symptomatic paroxysms of AF. 4. Long term - catheter ablation and a pacemaker.
532
What score can be used to calculate the risk of stroke in someone with atrial fibrillation?
CHADS2 VASc.
533
What does the CHADS2 VASc score take into account?
1. Age. 2. Hypertension. 3. Previous stroke/TIA. 4. Diabetes. 5. Female. A score >2 indicates the need for anticoagulation.
534
Atrial fibrillation treatment: what might you give someone to help with rate control?
Beta blockers, CCB and digoxin.
535
Atrial fibrillation treatment: what might you give someone to help restore sinus rhythm (rhythm control)?
Electrical cardioversion or pharmacological cardioversion using flecainide.
536
What is the long term treatment of atrial fibrillation?
Catheter ablation - it targets the triggers of AF.
537
What are some complications of AF?
Heart failure Ischaemic stroke Mesenteric Ischaemia
538
What is Atrial Flutter?
Irregular organised atrial firing 250-350 bpm
539
What are the risk factors of atrial flutter?
Similar to aetiology of AF
540
What is the pathogenesis of Atrial flutter?
Atrial flutter is caused by a “re-entrant rhythm” in either atrium. This is where the electrical signal re-circulates in a self-perpetuating loop due to an extra electrical pathway. The signal goes round and round the atrium without interruption. This stimulates atrial contraction at 300 bpm. The signal makes its way into the ventricles every second lap due to the long refractory period to the AV node, causing 150 bpm ventricular contraction. It gives a “sawtooth appearance” on ECG with P wave after P wave.
541
What are the symptoms of atrial flutter?
Dyspnoea Palpitations
542
What is the diagnosis of Atrial flutter?
F wave - saw tooth pattern Often has a 2:1 block - 2 p waves for every 1 QRS
543
What is the treatment of Atrial flutter?
Acutely unstable - DC Synchronised Cardioversion Stable - Rhythm/Rate control w/ oral coagulation (prevent thromboemboli) Radiofrequency ablation - long term
544
What is Wolf parkinson White?
An AVRT which means there is an accessory pathway that exists for impulse conduction called the bundle of Kent. This is a Pre excitation syndrome (excites ventricles early causing a delta wave) This is not re-entry through the AVN. Often hereditary
545
What are the symptoms of Wolf parkinson white?
Palpitations Dizziness Dyspnoea
546
What is the ECG of Wolf parkinson white?
Slurred DELTA WAVES Short PR interval (<0.12s) Wide QRS (>0.12s)
547
What is the treatment of Wolf Parkinson White?
1. Valsalva Manoeuvre 2. IV adenosine (6mg, then 12mg then 12mg) to cease conduction. 3. Consider surgical radiofrequency ablation
548
What conditions can radiofrequency ablation be curative for?
Atrial Fibrillation Atrial Flutter Supraventricular Tachycardias Wolf parkinson White syndrome
549
What is Long QT syndrome?
A ventricular Tachyarrhythmia typically caused by a congenital channelopathy where mutations affect ion channels. This causes the QT interval to be 480ms +
550
What are some causes of Long QT syndrome?
Romano ward syndrome Hypokalaemia and Hypocalcaemia Drugs - Amiodarone/magnesium
551
What is Torsades De Pointes?
Polymorphic ventricular tachycardia in patients with prolonged QT. Rapid irregular QRS complexes which twist around baseline. Can cease spontaneously or develop into ventricular fibrillation.
552
What is ventricular fibrillation?
Shapeless rapid osscillations on ECG patients becomes pulseless and goes into cardiac arrest - no effective cardiac output
553
What is the first line treatment for Ventricular fibrillation?
Electrical defibrillation
554
What are the narrow complex tachycardias?
Rapid cardiac rhythm > 100bpm, QRS complex <120ms: Supraventricular tachycardia Atrial fibrillation/flutter
555
What are the broad complex tachycardias?
Rapid cardiac rhythm >100bpm, QRS complex >120ms Ventricular tachycardia Supraventicular tachycardia with bundle branch block/pre-excitation
556
Give 4 causes of sinus bradycardia.
1. Ischaemia. 2. Fibrosis of the atrium. 3. Inflammation. 4. Drugs.
557
Give 3 causes of heart block.
1. CAD. 2. Cardiomyopathy. 3. Fibrosis.
558
What are the 3 types of AV block?
First degree Second degree - Mobitz type I and Type II Third degree
559
What does first degree AV block look like on an ECG?
1:1 conduction - Every P wave has QRS followed Prolonged PR interval >200ms
560
What are the symptoms of First Degree AV Block?
No symptoms No treatment
561
What can cause first degree AV block
Drugs - block AVN conduction. bB CCB Digoxin
562
What does second degree AV block look like on an ECG?
When some P waves are conducted and others aren't 2:1 conduction - Every other P wave is followed by a QRS complex
563
What are the types of Second degree AV block?
Mobitz I Mobitz II
564
What is Mobitz type I heart block?
PR interval gradually increases until AV node fails and no QRS is seen. This then Repeats
565
What is Mobitz type 2 Heart Block.
PR interval is constant but every nth QRS complex is missing. There is a sudden unpredictable loss of AV conduction and so loss of QRS.
566
What is the treatment for second degree heart block?
Pacemaker
567
What are some causes of Mobitz Type I and type II?
Type I - Beta blockers, CCB, Dixogin, inferior MI Type II - Inferior MI, Rheumatic Fever
568
What is 3rd degree AV block?
Atrial activity fails to conduct to the ventricles. P waves and QRS complexes therefore occur independently.
569
What can cause 3rd degree heart block?
Acute MI HTN Structural heart disease
570
What is the treatment for 3rd degree heart block?
IV Atropine Permanent Pace maker
571
What is the Pathogenesis of Bundle Branch Block?
Where electrical conduction down the left/right bundle branch in the bundle of HIS/septum is blocked/delayed often by fibrosis. This causes the impulse conduction to the ventricles to occur at different times creating a second R wave in the leads associated with the right/left ventricles on an ECG. In LBBB - LV contraction later than RV In RBBB - RV contraction later than LV
572
Give the causes of Left/Right Bundle Branch Block?
Left - IHD, valvular disease Right - PE, IHD, valvular disease
573
LBBB: what would you see in lead V1 and V6?
A 'W' shape would be seen in the QRS complex of lead V1 and a 'M' shape in V6. WiLLiaM.
574
RBBB: what would you see in lead V1 and V6?
A 'M' shape would be seen in the QRS complex of lead V1 and a 'W' shape in V6. MaRRoW.
575
What ECG changes are you likely to see in ischaemia and infarction?
T wave flattening and inversion ST segment depression first → progresses to ST elevation Q waves (old infarction)
576
Infarction involving the left anterior descending coronary artery will give rise to changes in which ECG leads?
Anterior leads: V2, V3, V4
577
Infarction involving the L circumflex coronary artery will give rise to changes in which ECG leads?
Lateral: V5, V6
578
Infarction involving the R coronary artery will give rise to changes in which ECG leads?
Inferior: II, III, aVF
579
Give 3 effects of hyperkalaemia on an ECG.
1. Tall 'tented' T waves. 2. Flat P waves. 3. Broad QRS.
580
Give 2 effects of hypokalaemia on an ECG.
1. Flat T waves. 2. QT prolongation. 3. ST depression. 4. Prominent U waves.
581
Give an effect of hypocalcaemia on an ECG.
1. QT prolongation. 2. T wave flattening. 3. Narrowed QRS. 4. Prominent U waves.
582
Give an effect of hypercalcaemia on an ECG.
1. QT shortening. 2. Tall T waves. 3. No P waves.
583
What is Deep Vein Thrombosis?
When a thrombus forms in deep leg vein Below calf - less concerning and most common Above calf/thigh - life threatening
584
What are the Risk factors for DVT?
Virchows triad: Venous Stasis Hypercoagulability Endothelial Injury OC pill HRT Pregnancy
585
What are the symptoms of DVT?
Unilateral swollen calf/engorged leg veins Typically warm Oedematous In severe oedema - leg turns blue
586
What is the diagnosis of DVT?
Clinical history + WELLs Score >1 D-dimer raised and Duplex ultrasound (gold standard) (D dimer normal excludes DVT, but positive does not confirm) CT or MR venogram
587
What is the treatment of DVT?
DOAC anticoagulant therapy Apixaban LMWH (if above CI in renal impairment)
588
What are some important differential diagnoses of DVT?
Cellulitis - S.aureus / S.pyogenes Leukocytosis
589
Why does DVT lead to ischaemia and loss of leg?
DVT leads to increased compartment pressure resulting in venous hypertension. This can compress the arterioles reducing their blood suplly and resulting in ischaemia to the local tissues.
590
What is the prevalence of DVT/PE?
25,000 people die per year due to DVT/PE in the UK
591
How can DVT be prevented?
Mechanical: Hydration Early mobilisation Compression stockings Chemical: LMWH
592
What pathophysiological features will cause a murmur
Increased Turbulent blood flow: Increased Velocity of blood: - Through a stenosed valve/ narrow VSD/ASD - Increased contractile strength of myocardium - Decreased Diameters - through HOCM narrowing the exit of the ventricle to the Aorta Decreased Viscosity of blood - through anaemia Blood flow back across incompetent valves
593
Where do you listen to different Murmurs/ Heart sounds? What is the Mnemonic to remember them?
All Physicians Earn Too Much: Aortic Valve - R. 2nd ICS - CoA, AS, AR Pulmonic Valve - L. 2nd ICS - PS, PR, ASD ERBS Point - L 3rd ICS - S1 +S2, HOCM Tricuspid Valve - L 4th ICS - TS, TR, VSD Mitral Valve - L 5th ICS, (MCL) - MR, MS
594
Where would a murmur caused by Aortic Stenosis best be heard and where would it radiate to?
Best Heard - Right parasternal boarder, 2nd intercostal space Radiates to - Carotids as it flows up through the aortic arch vessels
595
Where would a murmur caused by Aortic Regurgitation best be heard and where would it radiate to?
Best Heard - Right Parasternal Boarder, 2nd intercostal space Radiates to - Left upper sternal boarder (2nd/3rd ICS) due to blood flowing back across the left side of the heart
596
Where would a murmur caused by mitral regurgitation best be heard and where would it radiate to?
Best Heard - Left 5th ICS, mid clavicular line Radiates to - Axilla as blood is flowing up into the left atria which is towards the axilla
597
What would a blowing (musical Murmur) suggest?
Blowing Murmurs are usually regurgitation murmurs: Aortic Regurgitation Mitral Regurgitation
598
What would a Rumbling (Harsh) murmur suggest?
Valvular Stenosis: Aortic Stenosis Mitral Stenosis
599
What would a Machine Like Murmur suggest?
Patent ductus Arteriosus
600
what kind of pitch would a VSD murmur have?
High pitch due to high pressure gradients as the blood flows from the LV to the RV through the VSD
601
What kind of pitch would a Mitral stenosis murmur have?
Low pitch Due to low pressure gradient from the atria to the ventricles But high blood flow across the valve creates a low pitch
602
What kind of pitch would a Aortic Stenosis/ Aortic Regurgitation /Mitral regurgitation murmur have?
Harsh High pitch High pressure gradients High blood flow across the valve
603
What conditions would cause an Early Systolic Murmur? What is the motion of the murmur?
Aortic/Pulmonic Stenosis: Valves are rigid and so upon LV contraction the valves bow (not open properly) causing an EJECTION CLICK sound as blood hits the underside of the valve. CRESCENDO DECRESCENDO murmur as the blood velocity increases during systole and then falls of as the blood is ejected HOCM: CRESCENDO DECRESCENDO murmur with NO ejection click Coarctation of the Aorta
604
What conditions would cause an Holo-Systolic Murmur? What is the motion of the murmur?
Mitral/Tricuspid Regurgitation: Murmur occurs through entire systolic time period as blood is flowing back across the valve into the atria the entire time the ventricles contract VSD: As the LV contracts blood is flowing across the VSD into the RV causing turbulent flow in the RV.
605
What conditions would cause an Diastolic Murmur? What is the motion of the murmur?
Aortic/Pulmonic Regurgitation: During Early diastole (right at the start) the LV pressure decreases so blood can back flow across the Aortic valve hitting the LV wall causing turbulent flow Lots of blood flows in early diastole which falls off in late diastole. This causes a DECRESCENDO Murmur Mitral/Tricuspid Stenosis: OPENING SNAP (immediately at the start of diastole) followed by lots of blood entering the ventricles in early diastole which then reduces as diastole progresses causing a DECRESCENDO murmur
606
What kind of murmur would be heard in a Patent Ductus Arteriosus?
A Continuous "Machine" Murmur due to a constant shunt from the aorta to the pulmonary artery
607
Where does thrombosis occur?
Arterial circulation - High pressure (platelet rich) Venous Circulation - Low pressure (fibrin rich)
608
What are the main sites for Arterial thrombosis?
Coronary Cerebral Peripheral Other sites
609
What can lead to arterial thrombosis development?
Atherosclerosis Inflammatory Infection Trauma Tumours Unknown
610
What conditions can arterial thrombosis lead to?
Myocardial Infarction Cerebral Vascular Disease Peripheral Vascular Disease
611
What is the Treatment for Arterial thrombosis?
Anti-platelets: Aspirin LMWH or Fondraparinux Thrombolytic therapy: Streptokinase OR TpA Reperfusion - PCI
612
Why is heparin avoided to treat cerebral vascular disease/ cerebral thrombosis
Heparin has a high risk of bleeding
613
What are the main sites of venous thrombosis?
Peripheral - Ileofemoral, Femoro-popliteal Other sites - Cerebral, Visceral
614
What diagnostic tests are required for Venous thrombosis diagnosis?
Signs and Sx are very non-specific Blood tests - D-dimer - sensitive but not specific Imaging usually required
615
What is the main group of factors that leads to venous thrombosis?
Virchows Triad
616
What is important for Venous thrombosis prevention?
Mechanical/chemical thromboprophylaxis Early mobilisation and good hydration
617
What are the treatments for Venous thrombosis?
Anti-Coagulants: Heparin/LMWH Warfarin DOAC
618
What is Heparin and how does it work?
Glycosaminoglycan Given by Infusion Binds to anti-thrombin and increases its activity. Indirect thrombin inhibitor
619
What is the half life of Heparin and how is it monitored?
4 hours Monitor with APTT (anti-prothrombin time)
620
What is LMWH?
Smaller molecule of heparin that is excreted renally. Weight adjusted dose given via SC injection Used for Tx and Prophylaxis
621
What is the Half lifeof LMWH?
12 hours and therefore can be given once daily and not necessarily needed to be monitored
622
What is Warfarin?
Anticoagulant that prolongs the Prothrombin time Prevents synthesis of Active factors II, VII, IX, X Antagonist of Vitamin K
623
How can warfarin be reversed?
Give Vitamin K
624
What is the half life of Warfarin?
36 hours
625
What are NOACs/DOACs?
New oral anticoagulant drugs/ Direct oral anticoagulant drugs Directly act on Factor II or X
626
What is NOAC/DOAC used for? When would NOAC/DOAC not be used
Extended thromboprophylaxis and treatment of AF, DVT and PE Not used in pregnancy
627
What is the mechanism of action of Aspirin?
Inhibits Cyclo-oxygenase irreversibly. Prevents thromboxane formation and therefore inhibits platelet aggregation
628
What is a pulmonary embolism?
When an embolus (often from a thrombus/DVT) travels through the venous circulation and into the pulmonary circulation to get lodged in the pulmonary vasculature.
629
What are the symptoms of PE?
Signs: Tachycardia Tachypnoea Pleural rub SX: Breathlessness Pleuritic chest pain High RFs
630
What are some differential diagnoses to think of for PE?
DDx of chest pain and SOB
631
What are the initial investigations for PE?
CXR - usually normal ECG - Sinus Tachy - S1Q3T3 D-Dimer and CTPA (GS - CT scan and Pulmonary angiogram) Blood gases - Type I resp failure (Decreased O2/CO2)
632
What is the treatment of PE?
Supportive Tx and Tx underlying cause Apixaban DOAC LWMH (if CI for renal impairment)
633
What can be done to prevent PE?
Early mobilisation and hydration. Anticoagulation
634
How would a Massive PE be Tx?
Thrombolytics - Alteplase (clot buster)
635
When would you hear S3 in pathology?
Left ventricular failure (DCM) Constrictive pericarditis Mitral Regurgitation
636
When would you hear S3 in pathology?
Left ventricular failure (DCM) Constrictive pericarditis Mitral Regurgitation
637
When would you hear S4 in pathology?
Aortic stenosis HOCM Hypertension