Cardio Flashcards
Atherosclerosis is a primary cause of which three diseases
Heart attack, stroke and gangrene of the extremities
What affects the distribution of atherosclerotic plaques
Haemodynamics (flow and turbulence) cause media thinning and altered gene expression
Angina pectoris
Pain in the centre of the chest which is brought on by exercise and relieved by rest, may spread to the jaw and arms. Caused by increased myocardium oxygen demand and insufficient supply by the coronary arteries. Almost exclusively secondary to atherosclerosis
What is the response to injury hypothesis
Atherosclerosis is initiated by injury to endothelial cells leading to endothelial dysfunction, leukocyte accumulation and migration
What is ischaemia-reperfusion injury
Reintroduction of blood flow following ischaemia causes oxidative stress and neutrophils migrate causing inflammation and further damage to the tissue
Name some examples of good inflammation
Pathogens, parasites, tumours and wound healing
Name some examples of bad inflammation
Myocardial reperfusion injury, IHD, atherosclerosis, Rheumatoid arthritis and asthma
What are the two factors which ignite inflammation in the arterial wall
LDL and endothelial dysfunction
Which inflammatory cytokines are found in plaques
IL-1, IL-6, IL-8, INF-gamma, TGF-beta, MCP-1
What are foam cells
Lipid laden macrophages
What are the two types of coronary arteries
Epicardial (Run along surface of the heart, LAD, RCA, Cx) and small vessels (run within the cardium)
What are causes of angina
Atherosclerosis, anaemia, obstruction of vessels (ie from LV hypertrophy) increasing distal resistance
Name three other causes of angina besides atherosclerosis
Prinzmetals (coronary spasm), Syndrome X (microvascular resistance), Crescendo and unstable angina: ACS
What are the 3 factors needed for angina pain
heavy central tight radiates, exertion preciptitates, relieved by rest/GTN
Angina differential diagnosis
Pericarditis, PE, Chest infection, Aortic dissection, GI, MSK, psychological
Signs of complications on examination
Scars (midline sternonotomy, pacemaker, legs)
What is a sign unique to angina
Leivens sign, where they clutch hand across chest
What are the signs of angina on ECG and Echo
There are no direct signs. Can show IHD or previous infarcts
What are the signs of IHD and previous infarcts on ECG and Echo
Q waves, T wave inversion and BBB
What sign on an ECG during exertion indicates ischaemia
ST depression
Name two beta 1 specific beta blockers
Atenolol and bisoprolol
Beta blocker side effects
Tiredness, nightmares, bradycardia, cold hands and feet, erectile dysfunction
Beta blocker contraindications
Asthma, excess bradycardia, heart block, prinzmetal’s angina
How do nitrates treat angina
As venodilators they reduce the preload, work and oxygen demand of the heart. They also dilate the coronary arteries.
How do CCBs treat angina
As arterodilators they reduce the afterload, work and oxygen demand of the heart. They also dilate the coronary arteries and are negatively ionotropic
Is a CABG or PCI used in STEMI
Definitely PCI
Is a CABG or PCI used in NSTEMI
CABG can be used but PCI preferred
CABG or PCI in stable angina
Either. CABG more invasive but better prognosis and for complex disease
What is the J point on the ECG
Point of inflection between QRS complex and T wave (end of s wave, start of ST segment)
What difference is needed to consider it elevation or depression
One box
What are Q waves caused by
Absence of electrical activity due to scar tissue, therefore a sign of previous infarction
Name the features of a non Q wave MI
Poor R wave progression, ST elevation and biphasic T wave
Features of a Q wave MI
No R wave, too late to treat
What is the primary cause of ACS
Atherosclerotic plaque rupture and subsequent thrombosis
In which groups are silent ACS more commonly seen
The elderly and diabetic
Name some lesson common causes of ACS
Coronary vasospasm, aortic dissection, drug abuse and coronary artery dissection due to defects of vessel connective tissue
What are the signs of heart failure
Raised JVP, 3rd Heart Sound and basal crepitations
What is a pansystolic murmur a sign of
Papillary muscle dysfunction/rupture or VSD
Which two molecules are most associated with cardiac muscle damage
Troponin I and T
How do troponin levels differ in ACS vs other cardiac conditions
Big changes hour to hour, peaking at two hours. Whereas in non ACS there is ongoing damage so little change
How does aspririn work
It irreversibly inhibits COX (thromboxane synthetase), reducing the production of the pro-aggregatory factor thromboxane from arachidonic acid
Why is aspirin effective at low doses
As platelets just have a short life time and are anucleate so unable to produce more COX, the effects therefore only wear off as new platelets are made
What is the purpose of platelet alpha granules secretion
Coagulation and inflammation
What is the purpose platelet dense granules secretion
Contribute to platelet activation
What catalyses the conversion of plasminogen to plasmin
tPA
What catalyses the conversion of fibrin to FDP
Plasmin
Name a P2Y12 antagonist and its effects
Clopidogrel reduces amplification of platelet activation
Name a GPIIb/IIIa antagonist and its effects
abciximab, prevents platelet aggregation
What delays the absorption of some antiplatelet drugs
Opiates like morphine
Which anticoagulant is used in NSTE ACS
Fondaparinux, a low level anticoagulant
What is the initial pain relief used in ACS
Morphine+Metaclopramide, nitrates
What is the antianginal pharmacological therapy
Beta blockers, nitrates, calcium channel blockers
What is the secondary prevention in ACS pharmacological therapy
Statins, ACE inhibitors, Beta Blockers or other antihypertensives
What is the pharmacological therapy in heart failure patietns
Diuretic, ACEI, Beta blocker, aldosterone antagonist
Name an aldosterone antagonist
Spironolactone
What is the treatment of acute STEMI when PCI is not available
Fibrinolytic intervention
What is tako-tsubo
Stress induced cardiomyopathy
Factors affecting response to clopidogrel
Dose, age, weight, DM or CKD, Cytochrome P450 inhibitors or dysfunction
How does tricagelor work
Reversible P2Y12 inhibitor and inhibits adenosine uptake in the ENT pathway
What are common P2Y12 inhibitor side effects
Bleeding, rash, GI disturbance
When are nitrates given in ACS
Unstable angina and coronary vasospasm
Define ECG
Representation of the electrical events of the cardiac cycle
What is the intrinsic rate of the SA node
60-100bpm
What is the intrinsic rate of the AVN
40-60bpm
What is the intrinsic rate of ventricular cells
20-45bpm
Define syncope
Temporary loss of consciousness due to insufficient blood supply to the brain
What is the standard calibration of ECG
25mm/s 0.1mV/mm
What does the P wave represent
Atrial depolarisation
What does the QRS complex represent
Ventricular depolarisation
What does the T wave represent
Ventricular repolarisation
What is the PR interval
The time taken for atrial depolarisation and delay in the AV junction (AV node and bundle of his) - start of P till QRS
What are PR segment abnormalities associated with
Pericarditis or atrial ischaemia
What is the PR segment
End of P till QRS
What are ECG leads
Leads which measure the electrical potential between two points
Whats the difference between bipolar and unipolar leads
Bipolar leads= two different points on the body, Unipolar leads= one point on the body and a virtual reference point with 0 electrical potential in the centre of the heart
What is lead 1
Right to left shoulder 0 degrees
What is lead 2
right arm to left leg, pointing down 60 degrees
What is lead 3
Left arm to left leg, 120 degrees
What is aVR
Augmented vector right, shoulder -150 degrees
What is aVL
Augmented vector left, shoulder -30 degrees
What is aVF
Augmented vector foot, pubic symphsis 90 degrees
What does the QRS complexes in leads I and II pointing away from each other represent
Lovers Leaving, Left axis deviation
What does the QRS complexes in leads I and II +- III pointing towards each other represent
Lovers returning, Right axis deviation
Where is lead 1
Information between aVL and a VR
Where is lead 2
Information between aVL and aVF
Where is lead 3
Information between aVF and aVR
V1 position
4th intercostal space, right border of the sternum
V2 position
4th intercostal space, left border of the sternum
V3 position
Midway between the placement of leads V2 and V4
V4 position
5th intercostal space, midclavicular line
V5 position
Anterior axillary line on same horizontal level as V4
V6 position
Midclavicular line on same horizontal level as V4,5,6
Which ECG leads represent the lateral heart territory and which coronary artery supplies this
I, aVL, V4-6 Circumflex
Which ECG leads represent the anterioseptal heart territory and which coronary artery supplies this
V1-3 LAD
Which ECG leads represent the inferior heart territory and which coronary artery supplies this
2,3,aVF (VF=2 AND 3 LINES), RCA (80%) Cx (20%)
Which ECG leads represent the posterior territory and which coronary artery supplies this
V7-9 and Cx
What can a tall pointed P wave suggest
Right atrial hypertrophy or high atrial pressure, such as in COPD ‘p pulmonale’
What can a notched P wave in limb leads suggest
Left atrial problem eg mitral valve disease ‘p mitrale’
What is the R wave
The first positive deflection in the QRS complex
What is the Q wave
The first negative deflection in the QRS complex
What is the QT interval for a heart rate of 70bpm
Less than 0.40s
What factors increase the chance of seeing U waves
Bradykinia or hypothermia or slow heart rate
What is the rule of 300
300/big boxes between two QRS is the bpm
What does the QRS axis represent
Overall direction of the heart’s electrical activity
What is the normal axis
-30 to +90 degrees
What is a left axis deviation
-30 to -90 degrees
What is a right axis deviation
+90 to +180 degrees
In which direction does the IV septum depolarise
Left to right
Name causes of hypertension
85% aetiology unknown, 15% aldosterone overproduction 5% other inc renal failure, drugs and hormone secreting tumours
What is Conns syndrome
Overproduction of aldosterone due to a unilateral adrenal adenoma which causes sodium and fluid retention
Which drugs cause HTN
NSAIDS, combined oral contraceptives, corticosteroids, ciclosporins, cold cures, SRNI antidepressants, some recreational drugs such as cocaine and amphetamine
What is malignant hypertension
Rapid rise in HTN, untreated=dead within 6 months, causes immediate damage to small blood vessels in kidneys and eyes, look to the eyes to check
What is phaechromacytoma
Rare adrenal tumour causing excessive adrenaline and noradrenaline production
How does angiotensin cause HTN
Causes vascular growth, salt retention and increased peripheral resistance
How are RAAS linked
Sympathetic stimuli can cause renin release from kidney and Angiotensin II can cause noradrenaline release
Name an ACE inhibitor and how they work
Ramipril, Less Angiotensin II and therefore less vasoconstriction and aldosterone. Reducing PVR and therefore afterload and BP. Reducing fluid retention (less aldosterone and increased efferent arteriole pressure) and therefore preload, helping heart failure.
What is the effect of ACE-inhibitors on bradykinin production
Less conversion to inactive peptides. More bradykinin can lead to dry cough (10%), rash and anaphylactoid reactions
ACE inhibitors are most effective in which groups
Young people
When would an ARB be used in hear failure
When ACE-I is contraindicated, perhaps because of the dry cough caused by bradykinin
Name an ARB and how they work
Candesartan, blocks the peripheral angiotensin II receptor. AT-1
Name a CCB and how they work
Amlodidpine, inhibit voltage gated L-type calcium channels in vascular smooth muscle, reducing vasoconstriction
What are adverse effects from peripheral vasodilation
Flushing, headache, oedema and palpitations
What are adverse effects from negatively chronotropic agents
Bradycardia and AV block
What are the adverse effects from negatively ionotropic agents
Worsening heart failure
What is verapamil and an adverse effect
Phenylalkylamine CCB with negative chrono and ionotropic effects on the heart causes constipation
Name a BB and how they work
Metoprolol, targets B1 and reduces the chronotropic and ionotropic activity of the heart, prolongs AV node refractory period and reduces renin secretion
Which B receptors are found in the heart
60% B1, 40% B2
Which are the more B1 selective beta blockers
Metropolol and bisoprolol
What do thiazide diuretics target and an example
Sodium reabsorption via luminal Na/Cl cotransporter in the DCT, bendroflumethiazide
What do loop diuretics target and an example
NaKCC cotransporters in the thick arm of the loop of henle, Furosemide
What do K+ sparing diuretics target and an example
Competitively binds to aldosterone receptors, on ENaC in DCT, sprionalactone
Loop diuretics main adverse effects
Hypovolaemia and hypotension, low electrolytes raised urea
Name an alpha 1 adrenoceptor blocker
Doxazosin
Name a centrally acting antihypertensive
Methyldopa
Name a direct renin inhibitor
Aliskiren
What is step 1 in HTN treatment
Under 55: ACE-I/ARB
Over 55 or afrocarribean: CCB
What is step 2 in HTN treatment
ACE-I/ARB and CCB
What is step 3 in HTN treatment
ACE-I/ARB and CCB and thiazide like diuretic
What is step 4 in HTN treatment
This is resistant HTN, consider higher dose thiazide, spironolactone, alpha or beta blocker
What drop would you expect after atenolol treatment
-10/-5
Define heart failure
An inability of the heart to deliver blood and oxygen at a rate commensurate with the requirements of the metabolising tissues, despite normal or increased cardiac filling pressures (Cardiac output is inadequate for the body’s requirements)
What is the most common cause of heart failure
Myocardial dysfunction from IHD
What is ADCHF and who gets it
Acute decompensated CHF with reduced ejection fraction (<40%), generally younger than 70 and male(IHD)
What are the three cardinal symptoms of HF and the two more specific symptoms
SOB, ankle oedoma and fatigue. Orthopnoea and paroxysmal episodic nocturnal breathing
What is orthopnoea
Breathlessness which prevents the patient lying down, they must be sitting up/standing
Causes of acute decompensation of chronic heart failure
Negative ionotropes, AMI, HTN, Obesity+Alcohol, super infection, AF and arrythmias, non compliance, NSAIDS
Complications of heart failure
Renal dysfunction, Rhythm disturbances, systemic thromboembolism, DVT and PE, LBBB and bradycardia, hepatic and neurological dysfunction
What is the role of ANP (atrial) and BNP (ventricular)
Assist the stretched atria by increasing the GFR and reducing sodium resorption, reducing fluid load, smooth muscle stretch and preload
What is the effect of AT 1 receptor activation
Vasoconstriction, water and salt retention
What is the effect of AT2 receptor activation
Vasodilation and antiproliferation with kinins
Name a pottasium sparing diuretic
Spironolactone, an aldosterone antagonist
What are hydralazine and nitrates
Vasodilators
What is digoxin
An ionotrope
Which races dont ACE-I work in
Afrocarribean - equatorial
Which 4 BB are aloud in those with HF
Bisoprolol, metrapolol, nivedrolol, calvetolol
What treatment is used in congestive heart failure with preserved ejection fraction
Diuretics
Which treatment doesnt work in AF
Beta blockers
Cardiac resynchronisation therapy
pace right ventricle, atrium and coronary sinus artery to left ventricle wall. This can resync heart and reduce mortality
Name some care issues in those with congenital heart problems
Intellectual disability, psychosocial issues, transition, explaining the lesion and prognosis, building independence/self reliance
What should be advised against in those with congenital heart defects
Pregnancy, heart cant tolerate extra strain
What are the four features of tetralogy of fallot
Ventricular septal defect, pulmonary stenosis, hypertrophy of right ventricle and overiding aorta
What is normal pulmonary pressure
30/10
What causes cyanosis
Desaturation of haemoglobin due to reduced oxygen levels or septal defects leading to mixing of blood
What does thrill as a clinical sign mean
buzzing sensation
What are the clinical signs of a large VSD
Small breathless skinny baby, increased heart size, rate and respiratory rate. Murmur varies in intensity
What are the clinical signs of a small VSD
Fully grown, normally asymptomatic with normal HR, RR and heart sound but can a loud systolic heart murmur and thrill
What direction does the cardiac shunt have to be to get cyanosis
Right to Left (unusual as Right normally lower pressure)
What are the clinical signs of ASD
Pulmonary flow murmur, fixed split second heart sound, big pulmonary arteries and heart on CXR
What is a primum ASD
Defect associated with AV valve abnormality
What is secondum ASD
Defect associated with a hole high in septum
What is sinus venosus ASD
Patent sinus venosus from development, leads to SVC entry into right atrium
What is AVSD and which condition is it associated with
Hole in heart, chambers and valves havent met in complete. Associated with Downs
When are ASD and AVSD operated on
When there is right heart dilatation
How do you differentially diagnose patent ductus arteriosus from eisenmengers
Both with have blue clubbed toes, but patent ductus arteriosus will have pink unclubbed fingers
What are the clinical signs of patent ductus arteriosus
Continous machinery murmur, if large big heart and breathless
What is coarctation of the aorta
Narrowing of the aorta at the site of insertion of the ductus arteriosus
What is a bruit
A murmur heard over a vessel with turbulent flow, commonly caused by narrowing of an artery
Clinical signs of coartctation of the aorta
Right arm HTN, murmur, bruits over scapulae and back from collateral vessels
What causes HTN in coarctation of the aorta
Reduced blood flow to the kidneys leads to increased blood pressure in the right arm, head and neck
Define pulmonary stenosis
Narrowing of the outflow tract of the right ventricle
What are the two valvular defects which cause murmur
Aortic stenosis and mitral regurgitation (ASMR)
What is the fontan procedure
Where a one ventricle circulation is formed
When does the glenn procedure do
Plugs the SVC into pulmonary artery
What does a fixed split second heart sound, sound like
Lub dub dub
What are percutaneous operations
Where it is done through needle puncture to the skin
Angioplasty meaning
Surgical repair or unblocking of an artery
Define syncope
(fainting), loss of consciousness due to a sudden drop in blood pressure, resulting in a temporarily insufficient flow of blood to the brain
Name causes of syncope
Vasovagal, situation and carotid sinus syncope; stokes-adams attacks (hypoglycaemia, orthostatic hypotension and anxiety)
