cardiovascular Flashcards
where can thrombosis occur?
- arterial circulation: high pressure: platelet rich
- venous circulation: low pressure fibrin rich
- Coronary circulation
- Cerebral circularion
- Peripheral circulation
- Other territories
what causes Arterial thrombosis?
Atherosclerosis
Inflammation
Infection
Trauma
Tumours
what are Arterial thrombosis Presentations?
Myocardial infarction
CVA - stroke
Peripheral vascular disease
Others
what is Leriche Syndrome?
occlusion in the distal aorta or proximal common iliac artery
traid of:
Thigh/buttock claudication
Absent femoral pulses
Male impotence
claudation mean pain due to lack of oxygen
what is Buerger’s Test?
assesses for peripheral vascular disease
- legs lifted for 1-2 mins - pallor observed
- sitting with legs hanging - blue then dark red due to vasodilation
healthy response is remaining pink colour
what are Arterial coronary thrombosis treatments?
- aspirin/antiplatelets
- LMWH or Fondaparinux or UFH
- Thrombolytic therapy: streptokinase tissue plasminogen activator
- Reperfusion – Catheter directed treatments and stents
what is Prinzmetal’s angina?
- transient episodes of coronary artery spasm
- occurs at rest/sleep
- calcium channel blockers
what are the treatments for Arterial cerebral thrombosis (stroke)?
- Aspirin, other anti-platelets, Thrombolysis - eg for stroke
- Catheter directed treatments (eg blasting thrombus), Reperfusion
what are treatments of thrombosis in other arterial sites of the body?
- Antiplatelets
- statins
what are venous thrombosis signs/symptoms?
non -specific
- can be calf pain, chest pain, breathlessness
what is a blood test for venous thrombosis?
D-dimer - not specific
- used to show theres no thrombus
how is a venous thrombus usually diagnosed?
imaging eg MRI
what is virchows triad?
factors that contribute to the development of thrombosis:
- blood flow - immobilisation - eg - long flights, surgury
- endothelium injury - trauma, infection
- blood constituents - genetic or conditions that lead to Hypercoagulability
what are the treatments for venous thrombosis?
Heparin or LMWH
Warfarin
DOAC - anticoagulants
what are preventions for venous thrombosis?
- Mechanical or chemical thromboprophylaxsis - stockings
- early mobilisation and good hydration
how is heparin given?
IV, continusly given, closely monitered
how is Low molecular weight heparin given?
Once daily, weight-adjusted dose given subcutaneously
what factors synthesis does warfarin prevent?
2, 7, 9, 10
(Antagonist of vitamin K)
what do New Oral Anticoagulant Drugs NOAC / DOAC act on?
factor 2 & 10
when is aspirin prescribed?
arterial thrombosis
- Inhibits thromboxane formation
how does clopidogrel act as an antiplatelet?
inhibits ADP induced platelet aggregation by irreversibly binding to the p2y12 receptors
what are signs/symptoms of DVT?
Symptoms: leg pain, swelling
Signs: tenderness, swelling, warmth, discolouration
what are signs/symptoms of pulmonary embolism and what can cause it?
- symptoms - breathlessness, pleuritic chest pain, syncope
- Signs: tachycardia, tachypnoea, pleural rub,
Signs of DVT - complication of DVT
what is a complications of pulmonary embolism?
Chronic thromboembolic pulmonary hypertension (CTEPH
- from fibrous tissue blocking vasculature
what is Pulmonary Embolism Differential diagnosis?
acute coronary syndrome
pneumonia
HF
Pneumothorax
musculoskeletal
pericarditis
how is pulmonary embolism treated?
- Supportive treatment - eg O2
- Anticoagulants: LMW Heparin & Oral warfarin, DOAC/NOAC
- Treat underlying cause
- embolectomy if severe
what are outcomes of atherosclerosis?
- ulceration
- thrombosis - acute ischemia
- growth - chronic ischemia
- necrosis - aneurysm development
what is acute/chronic lower limb ischaemia?
acute - 6Ps - acute-embolus (normally in heart - clots moves to peripheral circulation)
- includes acute on chronic ishaemia
chronic - rest pain, tissue loss
investigations of peripheral vascular disease
- physical examination - eg ulcers, hair loss, pallor
- Ankle-brachial pressure index (ABPI)
- Duplex ultrasound – shows the speed and volume of blood flow
- Angiography (CT or MRI)
- hand held doppler - weak pulse
management of limb ischaemia/caudation
caudation:
- lifestyle changes/exercise
- mediaction - Atorvastatin,Clopidogre
- bypass/stenting
ischaemia:
- Endovascular angioplasty and stenting
- Endarterectomy
- Endovascular thrombectomy/thrombolysis using catheter
- bypass surgery
what are 6Ps in limb ischaemia?
pain, pulselessness, pallor, poikilothermia, paresthesias, and paralysis
when is bypass surgery used in peripheral vascular disease?
(graft of vein)
after stents fail
- better patency and limb salvage rates
what are the treatment options for aortic aneurysm?
- endovascular - stents - require more follow ups etc.
- open surgery - no further follow ups or treatments - prefered option for long-term outcomes
what are the symptoms of aortic aneurysm?
-normally asymptomatic until severe
- Pain in the chest, abdomen, or back
- Hoarseness or difficulty swallowing (TAA)
- Shortness of breath
- Pulsating sensation in the abdomen
- (pre)Syncope
- Signs of shock (in cases of a ruptured aneurysm)
what is the most common aortic aneurysm?
abdominal
thoracic
what are treatments for venous disease
- lifestyle
- compression
- sclerotherapy- injection causing vein to shrink
- endo-venous
what is Cor pulmonale?
- pulmonary heart disease
- right side of the heart becomes enlarged/strained due to pulmonary hypertension
- eg due to pulmonary embolism/fibrosis, COPD, Interstitial lung diseases, sleep apnea
What are pulmonary embolism investigations?
- PE Wells score over 4=likely
- D-dimer - +ve - measure blood clots
- CT Pulmonary Angiography (CTPA) - gold
- echo/ecg
- xray - rules out pneumonia etc.
- blood gases - t1 resp failure, decreased o2 and co2
what are risk factors for Pulmonary embolism?
- DVT.
- Recent surgery.
- Significant immobility.
- Active cancer.
- pregnancy/postpartum
- recent MI
- increasing age
- smoking, obesity, contraceptives
what is massive pulmonary embolism?
haemodynamic instability
- HYPOTENSION, cyanosis, severe dyspnoea, right heart strain/ failure
- rare
- clot is bigger and more severe symptoms
what can atherosclerosis cause?
heart attack, stroke etc.
- due to plaque rupture leading to thrombus formation, partial/complete arterial blockage leading to a heart attack
where are atherosclerotic plaques mainly found?
within peripheral and coronary arteries
what do atherosclerotic plaques consist of?
Lipid/ fatty streak
Necrotic core
Connective tissue
Fibrous “cap”
what is the first step in atherosclerosis progression?
fatty streaks
- aggregations of lipid–laden macrophages and T lymphocytes within the intimal layer of the vessel wall
what is the second step in atherosclerosis progression?
intermediate lesions:
layers of:
- foam cells
-Vascular smooth muscle cells
- T lymphocytes
- Adhesion and aggregation of platelets to vessel wall
- Isolated pools of extracellular lipid
what is the third step in atherosclerosis progression?
fibrous plaques/advanced lesions
- impede blood flow, may rupture
- covered by dense fibrous cap
what is the fourth step in atherosclerosis progression?
plaque rupture
- due to Fibrous cap not being resorbed and redeposited - eg due to inflammation cap weakens
- thrombus/clot formation and vessel occlusion
what is the fifth step in atherosclerosis progression?
plaque erosion
- can cause coronary thrombosis
what is the difference between plaque ruption and plaque erosion?
ruptured - large lipid core and inflammatory cells
erosion - small lipid core, disrupted endothelium, more fibrous tissue and a larger lumen
what is the treatment for coronary heart disease?
- Percutaneous Coronary Intervention PCI
(widens blocked arteries)
(especially in STEMI)
What is the difference between STEMI and NSTEMI?
STEMI - complete blockage of coronary artery, more urgent
NSTEMI - partial blockage (ST-depression, T-wave inversion)
what is aspirin an irreversible inhibitor of?
platelet cyclo-oxygenase
what do statins inhibit?
HMG CoA reductase - reducing cholesterol synthesis
what kind of drugs can be used if statins are ineffective or not tolerated?
drugs that target PCSK9
what are acute coronary syndromes?
spectrum of conditions which include myocardial infarction with or without ST-segment-elevation, and unstable angina.
what is unstable angina an how is it diagnosed?
Clinical classification includes:
*Cardiac chest pain at rest
*Cardiac chest pain with crescendo pattern
*New onset angina
Diagnosis: history
ECG
troponin
what is the difference in symptoms between unstable/stable angina?
unstable - at rest, longer, more frequent
stable - with exercise/exertion, shorter, predictable
why is unstable angina more serious then stable angina?
unstable - ruptured/ unstable coronary artery plaques, can lead to heart attack
stable - narrowed but stable coronary artery plaques, usually no blockage
what other way may MI be classified?
Q-wave or non Q wave
what are risk factors of MI?
age
diabetes
renal failure
left ventricular systolic dysfunction
what signs/symptoms show MI?
cardiac chest pain - unremitting, severe but may be mild, occurs at rest
associated with sweating, breathlessness, nausea and vomiting
what is initial management of MI?
- aspirin 300mg immediately
- pain relief - opiates/nitrates
- o2 if hypoxic
- aspirin +/- platelet P2Y12 inhibitor
- consider beta-blockers
- Consider urgent coronary angiography e.g. if
troponin elevated or unstable angina refractory
to medical therapy
what is type 1 myocardial infarction?
Myocardial infarction due to atherothrombosis
what causes most acute cardiac syndromes
Rupture of an atherosclerotic plaque and
consequent arterial thrombosis
what are some causes of type 2 MI?
- drug abuse
- pulmonary embolism
- anaemia
- haemorrhage
- thyrotoxicosis
- sepsis - causing o2 mismatch
(imbalance between supply and demand other than coronary artery disease)
what is Tako-Tsubo/stress-induced cardiomyopathy?
- due to extreme emotional distress
- cause left ventricular systolic
dysfunction, typically ballooning of the left
ventricular apex during systole - reversible within couple weeks
what does troponin show?
markers for cardiac muscle injury
what are the 3 P2y12 inhibitors?
thienopyridines - clopidogrel & prasugrel (better prodrug) - irreversible
ticagrelor - reversible - more rapid offset
used in antiplatelet therapy and in ACS
what are Adverse effects of P2Y12 inhibitors?
Bleeding e.g. epistaxis, GI bleeds, haematuria
Rash
GI disturbance
ticagrelor - Dyspnoea (shortness of breath), Ventricular pauses
what are features of GPIIb/IIIa antagonists?
- used in combination, only IV
- increase risk of major bleeding
- reduced use due to better antiplatelet therapy
- used in patients with delayed absorption of oral P2Y12 inhibitors
what do anticoagulants target?
formation/activity of thrombin
- Inhibit both fibrin formation and platelet activation
what are the main anticoagulants?
fondaparinux or heparin
what acute coronary syndrome is revascularisation used for?
NSTE
high risk unstable angina
what are some predisposing factors for ischaemic heart disease?
- age
- smoking
- family history
- diabetes
- high BP, high lipids
- kidney disease
- obesity
- physical inactivity
what are symptoms of ischaemic heart disease?
- chest pain
- breathlessness
- fluid retention
- palpitations
- Syncope or pre-syncope - fainting
what are some differential diagnosis of ischaemic heart disease?
Pericarditis/ myocarditis - inflammation
Pulmonary embolism/ pleurisy
Chest infection/ pleurisy
Dissection of the aorta
Gastro-oesophageal (reflux, spasm, ulceration)
Musculo-skeletal
Psychological
how is ischaemic heart disease treated?
lifestyle changes
asparin, Beta blockers, statins
what are the side effects of beta blockers?
tiredness, nightmares
erectile dysfunction
cold hands and feet
how do nitrates affect the heart?
vasodilation
- lower BP and afterload, in turn lowering venous return and preload
- reduce oxygen demand of the heart
how do Ca channel blockers affect the heart?
- lower BP, lower O2 demand
- Suppression of Abnormal Rhythms
- increase blood flow
what is an antiplatelet agents (aspirin) side effect?
gastric ulceration
how do ACE inhibitors (ramipril) effect the cardiovascular system?
- inhibit angiotensin 2 synthesis that cause vasoconstriction
- LOWER BP
what are chronic coronary syndromes?
chronic mismatch between supply and demand in myocardial oxygen conspumtion
what medication is given for chronic coronary syndromes?
aspirin
b blockers
nitrates
what psychosocial factors can effect coronary heart diease?
- anxiety/depression
- lack of social support
- work/family life - stress
- ## anger/hostility
how are pscychosocial factors related to CHD assesed and what is done about it?
- assessed by clinical interview or standardized questionnaires
- in cases with increased risk multimodal, behavioural intervention, integrating counselling
what is Coronary Prone Behaviour Pattern?
‘type A’ behaviour
- eg highly competitive, ambitious, aggressive
what happens to a muscle during depolarisation?
contraction
what is the standard calibration of an ECG?
25mm/s
0.1 mV/mm
what does the p wave in an ECG show?
atrial depolarisation
what does the QRS wave show in an ECG?
ventricular depolarisation
what does the T wave show in an ECG?
ventricular repolarisation
what does the PR interval show in and ECG?
- represents the time for electrical activity to move between the atria and the ventricles
- time between atria depolarisation and ventricular depolarisation
(between P and Q point)
what are the 12 leads in an ECG?
3 standard limb leads
3 augmented limb leads
6 precordial leads
what is a normal PR interval range?
120 to 300 ms
(3 to 5 little squares)
what should the width of a QRS complex be?
less than 110 ms ( 3 little squares)
what leads is the QRS complex are upright?
lead 1 and 2
the QRS and what wave tend to have the same general direction in the limb leads?
T wave
in lead aVR, what are all the waves?
negative
where does the R and S wave increase in size?
R wave - V1 to at least V4
S wave - V1 to at least V3, disappear in V6
what part of a normal ECG may a ST segment be elevated?
V1 and V2
starts isoelectric
where is the P wave upright in a normal ECG?
1, 2, V2 to V6
what part of the ECG is there no Q wave (or less than 0.04s)?
1, 2, V2 to V6
what part of a normal ECG must a T wave be upright?
1, 2, V2 to V6
what should a P wave look like in an ECG?
+ve in lead 1 and 2
-ve in lead aVR
<3 squares in duration, <2.5 squares in amplitude
commonly biphasic in lead V1
best seen in lead 2
in an ECG, what shows right atria enlargement?
pointed P wave, over 2.5mm
- P pulmonale
in an ECG, what shows left atrial enlargement?
M shaped/bifid P wave
- P mitrale
what shows WPW, wolff-parkinson-white syndrome in an ECG?
short PR interval
(and tachycardia)