Cardiology Flashcards
what is angina?
chest pain/discomfort arising from the heart as a result of myocardial ischaemia - usually due to narrowing of lumen of CAD due to atherosclerosis/thrombosis
name 3 types of angina
classic/stable, unstable/crescendo, Prinzmetal’s. decibitus (lying down), nocturnal.
what are the differences between stable and unstable angina
stable angina is induced by effort + relieved by rest. unstable angina occurs at rest - treat as ACS.
what is Prinzmetal’s (variant) angina?
angina that occurs without provocation, usually at rest - due to coronary artery spasm.
what causes angina?
atheroma of coronary arteries leading to myocardial ischaemia
give 5 risk factors for angina
diabetes, smoking, hyperlipidaema, hypertension, family history, lack of exercise
list the differential diagnoses of central chest pain
angina, ACS, pericarditis, myocarditis, aortic dissection, massive PE, musculoskeletal, GORD
describe the presentation of angina
central, crushing, retrosternal chest pain - comes on with exertion, relieved by rest. may radiate to arms and neck
list some things that can exacerbate angina
exercise, cold weather, anger, excitement, heavy meals
give some clinical features, apart from pain, of angina
dyspnoea, nausea, sweating, faintess
what investigations would you carry out on a patient with angina? what would you find?
12 lead ECG - shows ischaemic changes at exercise stress test - FBC, glucose, LFT (pre-statin), U&E (renal func), TFT, lipids
functional scans - MRI perfusion scan etc.
how would you manage stable angina?
refer all suspected angina to rapid access chest pain clinic - within 2wks, for confirmation of Dx and severity assessment. - modify risk factors, patient education. - secondary prevention - aspirin 75mg or clopidogril, statins, treat HTN. - symptomatic treatment - GTN spray (and rest!) - first line = beta blockers (atenolol - low HR/BP, cold hands/feet, fatigue) or CCB (diltiazem/verapamil/amlodipine - ankle swelling, flushing) - second line = combo (must be dihydropyridine - if intolerant/CI - long acting nitrate or nicorandil or ivabradine.
how does aspirin work as a method of secondary prevention in angina?
inhibits COX2 and formation of thromboxane A2 - a platelet aggregating agent. reduces risk of coronary events.
name an alternative to aspirin in secondary prevention of coronary events.
clopidogrel
give some examples of beta-blockers
bisoprolol, atenolol, propranolol, metoprolol
describe the mechanism of action of beta blockers in improving symptoms of angina
by acting on beta1 receptors in the heart, they reduce the force of contraction and speed of conduction in the heart - relieves myocardial ischaemia by reducing cardiac work and oxygen demand
what is the major contra-indication of beta-blockers? why?
asthma - beta blockers also act on beta2-receptors which are found in the smooth muscles of airways - cause bronchoconstriction!
give some examples of calcium channel blockers
diltiazem, amlodipine, nifedipine, verapamil
describe the mechanism of action of calcium channel blockers in controlling symptoms of stable angina
they decrease calcium entry into vascular and cardiac cells. they reduce myocardial contractility and suppress cardiac conduction - reduce heart rate, contractility and afterload - reduces myocardial oxygen demand - prevents angina.
what are the major side effects of calcium channel blockers?
postural hypotension/dizziness, headache, ankle oedema - due to systemic vasodilation
describe the mechanism of action of short-acting (GTN) nitrates and long-acting nitrates in acute angina
Nitrates are converted to NO, which increases cGMP and reduces intracellular calcium in vascular smooth muscle cells - vasodilation of venous capacitance vessels reduces preload and LV filling. reduced cardiac work and myocardial oxygen demand - relieve angina
what interventions may be used in worsening angina, not resolved with drugs?
Percutaneous coronary intervention (PCI) - balloon used to dilate atheromatous arteries (stents can be placed) - via catheter. Coronary artery bypass grafting (CABG)
what is involved in a coronary artery bypass graft (CABG)?
internal mammary artery used to bypass stenosis in the LAD or RCA.
what does the term acute coronary syndromes (ACS) include?
unstable angina. NSTEMI. STEMI.
how would you differentiate between NSTEMI and unstable angina?
NSTEMI involves enough occlusion to cause myocardial damage - elevation of serum troponin and creatinine kinase. unstable angina doesn’t cause myocardial damage. *troponin rise is the key distinction*
describe the common pathology behind acute coronary syndromes
1) rupture/erosion of fibrous cap of an atheroma plaque in a coronary artery 2) platelet-rich clot forms 3) vasoconstriction due to chemicals released by platelets
name 3 non-modifiable risk factors for ACS
age. male gender. FHx of IHD
name 3 modifiable risk factors for ACS
smoking, hypertension, DM, hyperlipidaemia, obesity, sedentary lifestyle, cocaine use
list 3 symptoms and 3 signs of ACS
symptoms - central chest pain, sweating, dyspnoea, palpitations. signs - sweating, anxiety, tachycardia, pallor.
what biochemical markers would you test for in ACS?
cardiac enzymes = troponin T, troponin I, creatinine kinase (CK-MB) troponins most sensitive within 6hrs. hit max at 12-24hrs post infarct, persistently high 14 days - should test trops at 6 and 12 hours. CK-MB = cardiac specific, trops can also be raised by skeletal muscle injury
what would you expect to see on a 12 lead ECG in ACS?
hyperacute (tall) T waves ST elevation (STEMI) or ST depression (NSTEMI/unstable angina). new LBBB. after hrs-days - T wave inversion, Q waves.
what would be your immediate management of ACS?
ABCDE resus. - GTN + IV opioid w/antiemetic (morphine + metoclopramide) = pain control - dual antiplatelet: loading dose is 300mg aspirin + 180mg ticagrelor - give high flow O2 if sats <94% - monitor 12 lead ECG NSTEMI - fondaparinux/heparin (antithrombotic), coronary angiography/revascularisation if appropriate STEMI - immediately assess suitability for reperfusion (PCI or fibrinolysis) - offer coronary angiography + PCI if presents within *12hrs of onset + PCI can be delivered within 120mins - if beyond that + continuing ischaemia = coronary angiography - fibrinolysis if presenting <12hrs but PCI not available within 120mins = alteplase, streptokinase - then re-ECG and consider if PCI needed.
what drugs might a patient be put on after an ACS, for secondary prevention?
beta-blockers, ACE inhibitors, statins, dual antiplatelet therapy (aspirin + clopidogrel)
what might the non-medical management of ACS be?
PCI - percutaneous coronary intervention
list some possible complications following a MI
heart failure, rupture of interventricular septum, mitral regurg, arrhythmias, heart block, pericarditis, thromboembolism, ventricular aneurysm
give 3 causes of heart failure
mostly - IHD and HTN also - valvular disease; pericarditis; pericardial effusion; alcohol; cocaine; myocarditis; arrhythmias; cardiomyopathies; anaemia; pulmonary hypertension. high output = anaemia pregnancy, hyperthyroid, Paget’s disease of bone
what are the types of heart failure?
systolic/diastolic, low output/high output, left/right
what compensatory mechanisms are activated as the heart begins to fail?
sympathetic nervous system, RAAS, ventricular dilatation, ventricular remodelling
what causes the oedema and dyspnoea seen in heart failure?
activation of the RAAS by decreased renal perfusion (due to low CO) - salt/water retention - peripheral/pulmonary congestion
describe the ventricular remodelling seen in heart failure
initial dilatation. hypertrophy, loss of myocytes, increased interstitial fibrosis.
what is the difference between systolic and diastolic failure?
systolic = inability of ventricles to contract normally diastolic = inability of ventricles to relax and fill normally
give 3 symptoms of heart failure
exertional dypnoea, orthopnoea (SOB on lying down), paroxysmal nocturnal dyspnoea, fatigue, oedema, weight loss, wheeze
give 5 signs of heart failure
cold peripheries, cyanosis, displaced apex, wheeze, RV heave, valve disease, hypotension, pleural effusion, oedema, ascites
what are 5 features of heart failure seen on CXR?
ABCDE: Aleveolar oedema (bats wings) Kerly B lines (interstitial oedema) Cardiomegaly Dilated upper lobe vessels pleural Effusion
list 2 major criteria on the Farmingham criteria for heart failure diagnosis
SAW PANIC S3 heart sound - gallop. Acute pulmonary oedema. Weight loss Paroxysmal nocturnal dyspnoea Abdominojugular reflux Neck vein distension Increased cardiac shadow on CXR (cardiomegaly) Crepitations (crackles heard in lungs)
list 2 minor criteria on the Farmingham criteria for heart failure diagnosis
HEART ViNo: Hepatomegaly Effusion, pleural Ankle oedema bilaterally exeRtional dyspnoea Tachycardia Vital capacity decrease by 1/3rd Nocturnal cough
describe the NHYA classification of heart failure
class I = no limitation class II = mild limitation (comfort at rest, fatigue and dyspnoea on normal physical activity) class III = marked limitation (comfort at rest, dyspnoea on gentle physical activity) class IV = symptomatic at rest, exacerbated by any physical activity
what investigations would you do in heart failure?
ECG - underlying cause. CXR. Bloods - BNP (B type natriuretic peptide - if normal, HF is unlikely). echocardiography.
describe the management of heart failure (not acute!)
1) lifestyle, pt education, cardiac rehab, inform DVLA, air travel likely fine unless needs O2 2) annual fluv vaccine, one off pneumococcal vaccine 3) manage comorbidities/cardiac RGs 4) Medical: - ACEi + beta blockers (ARB if can’t have ACEi, if can’t have either then hydralazine w/nitrate) - start low and titrate. - add aldosterone antagonist (spironolactone), ARB or hydralazine w/nitrate - 3rd line = digoxin or ivabradine - ICD if prev. vent arrhythmias. (I’m sure other diuretics get involved though…?)
name 2 ACE inhibitors
ramipril, lisinopril
what causes the common cough side effect of ACE inhibitors? what drug class are a good alternative?
increased levels of bradykinin, which is usually inactivated by ACE. ARBs
how do ACE inhibitors act?
prevent conversion of angiotensin I to angiotensin II. Angiotensin II is a vasoconstrictor and stimulates aldosterone secretion - blocking this reuces afterload, lowering BP.
name 2 angiotensin receptor blockers (ARBs)?
losartan, candesartan
how do angiotensin receptor blockers work?
block action of angiotensin II on the AT1 receptor. similar effects as ACE inhibitors.
give 3 causes of mitral stenosis
rheumatic heart disease (most), congenital, cardial fibroelastosis, malignant carcinoid, prosthetic valve.
what is mitral stenosis?
thickening and immobility of valve leaflets - leads to obstruction of blood flow from left atrium to left ventricle. occurs due to: - structural abnormality of valve leading to increase LA pressure + pulmonary artery pressure - pulmonary HTN - RV failure
give 3 symptoms of mitral stenosis
aymptomatic for years then deteriorate - progressive breathlessess (SOBOE/orthopnoea/PND), palpitations from AF, systemic emboli (static blood flow in LA). hoarseness/dysphagia due to enlarge LA
what is the heart murmur heard in mitral stenosis? other examination findings?
rumbling mid-diastolic murmur best heard on left lateral position. loud S1 with opening snap. malar flush, raised JVP, displaced apex/RV heave (RVH), signs of RHF (hepatomegaly, ascites, peripheral oedema)
what diagnostic tests would you perform in mitral stenosis? what would you see?
ECG - AF, bifid P waves (p mitrale). RVH. CXR - LA enlargement, interstitial oedema (Kerley A/B lines - if RHF), prominent pulmonary vessels Echo - diagnostic.
how would mitral stenosis be treated?
yearly F/U for dyspnoea = diuretics - decrease pre load, or nitrates. for exercise tolerance = beta blockers, non-dihydropyridine CCBs surgery if severe/symptomatic = balloon valvuloplasty / valve replacement (percutaneous mitral commisurotomy, PMC)
give 2 complications of mitral stenosis
pulmonary hypertension. emboli (dilated LA). pressure from large LA on local structures e.g. hoarseness due to compression of L recurrent laryngeal
give 3 causes of mitral regurgitation
prolapsing mitral valve + rheumatic heart disease = most common (actually now it’s more commonly degenerative!) MI, CAD, IE, post mitral valve surgery, connective tissue disorders (Ehlers-Danos, Marfan’s). cardiomyopathy, congenital.
give 3 symptoms of mitral regurgitation
acute = rapid pulmonary oedema, needs surgery chronically = causes heart failure so - dyspnoea, fatigue, palpitations, infective endocarditis
what murmur is heard in mitral regurgitation?
pansystolic blowing murmur at apex, radiating to axilla. laterally displaced apex beat. S3 gallop.
what does a bifid P wave indicate on ECG?
bifid P waves = p mitrale - mitral valve disease
what investigations would you perform in valvular heart disease?
ECG, CXR, echo ± cardiac catherization
what would you see on CXR in mitral regurgitation? what about ECG?
enlarged LA and LV. ECG = enlarged LA, p mitrale, AF.
how would you treat mitral regurgitation?
asymptomatic = echo every 1-5yrs. anticoagulate with warfarin if - AF, hx of embolism, prosthetic valve, additional mitral stenosis. medical (acute) - diuretics, nitrates surgery if signs of LV dysfunction or AF, or acute/severe - valve replacement or repair.
give 3 causes of aortic stenosis
degeneration and calcification of normal valve (in the elderly). calcification of congenital biscuspid valve (middle age). rheumatic heart disease. CAD.
what is the classical triad of symptoms in aortic stenosis?
SAD: Syncope Angina Dyspnoea - heart failure also often SOBOE
what murmur is heard in aortic stenosis?
ejection systolic murmur other examination findings: slow rising pulse, narrow pulse pressure. apex thrill secondary to LVH.
what would you expect to see on an ECG in aortic stenosis?
p mitrale, LVH with strain pattern (depressed ST and T wave inversion in I, AVL, V5 and V6)
what would you see on a CXR of a patient with aortic stenosis? what type of imaging should be used for confirming diagnosis?
normal heart size (or cardiomegaly), prominent ascending aorta, calcification of aortic ring echo (transthoracic, TTE) = confirms presence/degree, LV function + thickness might also do Doppler echo to assess severity.
how would you treat aortic stenosis?
avoid exertion, modify IHD RFs if symptomatic - prompt valve replacement. not fit for surgery? balloon valvuloplasty, TAVI.
what are the most common causes of aortic regurgitation?
rheumatic fever and infective endocarditis associated with SLE, marfan’s, ehler-danos, Turner’s, ank spond (aortic dilatation)
give 3 causes of acute aortic regurgitation
infective endocarditis, acute rheumatic fever, dissection of the aorta, AAA dissection, prosthetic valve failure
give 3 causes of chronic aortic regurgitation
chronic rheumatic heart disease, syphilis, rheumatoid arthritis, severe hypertension, biscupid aortic valve, aortic endocarditis, Marfan’s, osteogenesis imperfecta
give 3 symptoms of aortic regurg
acute - cardiovascular collapse. chronic - SOBOE/ nonspecific, or symptoms of LH failure = orthopnoea, paroxysmal nocturnal dyspnoea
what murmur is heard in aortic regurgitation? other examination findings?
early diastolic murmur. “at L sternal edge in 4th intercostal space” other finds = collapsing water hammer pulse, wide pulse pressure. austin flint murmur.
what would you see on CXR/ECG in aortic regurgitation? what other investigations should be performed?
CXR - if heart failure: cardiomegaly and dilatation of the ascending aorta, pulmonary oedema. ECG - LVH. do a TTE and colour doppler.
how would you manage aortic regurgitation?
if acute and symptomatic = surgery. chronic = try to prevent heart failure. mild-mod = r/v yearly, 2 yearly echo. severe = monitor every 6/12. screen family if Marfan’s. surgical - valve replacement. medical - ACEi/ARB for HTN/HF. if Marfan’s - beta blocker helps slow aortic root dilatation.
what are the 3 main cardiomyopathies? what does cardiomyopathy actually mean?
dilated (DCM) = most common, left (or both) ventricle dilated with impaired contraction hypertrophic = 2nd most common, L/R ventricular hypertrophy restrictive = rare, reduced diastolic filling, near normal systolic function. cardiomyopathy = myocardial disorder in which heart muscle is structurally and functionally abnormal, without CAD, valvular diease, HTN or congenital abnormalities
what is hypertrophic cardiomyopathy?
ventricular hypertrophy in absence of abnormal loading conditions - LV outflow tract obstruction. presents in 20s-30s –> most common cause of sudden cardiac death in young people/athletes (death due to arrhythmia or LV outflow tract obstruction). characterised by - LVH, mitral valve abnormalities, impaired diastolic filling, disorganised cardiac myocytes.
what causes hypertrophic cardiomyopathy?
50% = autosomal dominant, mutation in gene coding for beta-myosin or troponin. 50% = sporadic.
what is the major consequence of hypertrophic cardiomyopathy?
sudden cardiac death in young people
name 2 clinical features of hypertrophic cardiomyopathy
mainly asymptomatic. dyspnoea, chest pain, palpitations, syncope, sudden death, systolic thrill. O/E - forceful apex beat, harsh ejection systolic murmur
what investigations might you carry out in cardiomyopathy? what would they show?
ECG - LVH, ischaemia, LAD, AF. most common arrhythmias = premature ventricular complexes. echo = diagnostic. TTE shows asymmetrical septal hypertrophy >15mm. preserved systolic functioning. LV thickening. CXR = atrial enlargement if mitral regurg, variable cardiomegaly. genetic testing/counselling.
how would you treat hypertrophic cardiomyopathy?
beta blockers/CCBs to control symptoms. amiodarone or catheter ablation for rhythm control if AF (also anticoagulate) ICD if RFs for sudden death (e.g. Hx VFib, sustained tachy, unexplained syncope) genetic counselling avoid competitive sports
give 3 causes of dilated cardiomyopathy
characterised by ventricular chamber enlargement + contractile dysfunction w/normal LV wall thickness, due to biochemical abnormality of cardiac muscle. genetic (AD), *alcoholism, hypertension/IHD, thyrotoxicosis haemachromatosis, viral infection, autoimmune (SLE/RA), cocaine abuse
give 3 clinical features of dilated cardiomyopathy
often symptomless –> sudden death heart failure symps (L or R) dyspnoea, thromboemboli (stasis) or arrhythmia (AF or *VT), pleural effusion, oedema, jaundice, ascites O/E - displaced apex beat, S3 gallop.
how would you treat dilated cardiomyopathy?
bed rest. improve cardiac function by treating as for heart failure - diuretics, digoxin, ACE inhibitors, nitrates. biventricular pacing or ICDs. heart transplant.
what is restrictive cardiomyopathy?
rigid myocardium restricting diastolic ventricular filling –> increased atrial pressure
give 2 causes of restrictive cardiomyopathy
mostly old age, AF. weirder: amyloidosis. haemachromatosis. sarcoidosis. scleroderma. idiopathic.
give 3 clinical features of restrictive cardiomyopathy
constrictive pericarditis. raised JVP. oedema, ascites, features of RVH. usually present with heart failure, right sided mostly (as above). O/E - Kussmaul’s sign (increased JVP with inspiration), pulsus paradoxus (decreased pulse/BP on inspiration).
what investigation would you do in restrictive cardiomyopathy?
CXR = ABCDE of HF echo = non0dilated, non-hypertrophied ventricles, atrial enlargement (sparkling in amyloidosis) **cardiac catheterisation to assess pressures in different chambers - diagnostic. management is just as for heart failure and AF, mayyyybe transplant
what are the 2 causes of ventricular septal defect?
congenital. acquired post-MI.
how might a ventricular septal defect present?
severe heart failure in infancy. OR - asymptomatic, detected later in life
does a smaller ventricular septal defect produce louder or quieter murmurs?
louder
what murmur is heard in VSD?
harsh pansystolic murmur at left sternal edge
give 2 complications of a ventricular septal defect
aortic regurgitation, infundibular stenosis, IE, pulmonary hypertension, Eisenmenger’s complex.
what is seen on a CXR of someone with a ventricular septal defect?
Small VSD - normal sized heart ± enlarged pulmonary blood vessels. Large VSD - cardiomegaly, large pulmonary arteries, marked enlargement of pulmonary vessels.
how would you manage a ventricular septal defect?
medical support until spontaneous closure. OR - surgical patch repair or device closure.
what are the different types of atrial septal defect?
ostium secundum defects - most common - present in adulthood. ostium primum defects - associated with AV valve abnormalities - present early.
give 3 clinical features of an atrial septal defect - murmur?
pulmonary hypertension, cyanosis, arrhythmia, haemoptysis, chest pain, AF, raised JVP. pulmonary ejection systolic murmur.
what investigations are used to diagnose most structural heart defects?
echo. cardiac catheter.
how would you treat an ASD?
transcatheter or surgical closure
what genetic disorder is associated with atrioventricular septal defects?
Downs syndrome
what structures are involved in an atrioventricular septal defect?
atrial septum, ventricular septum, mitral and tricuspid valve
what are the clinical features and management of a complete AVSD?
breathless neonate, failure to thrive, poor feeding, torrential pulmonary blood flow. repair with PA band.
what are the clinical features and management of a partial AVSD?
presents in adulthood, similar to small ASD/VSD. treatment not necessary.
what is a patent ductus arteriosus?
persistent communication between left pulmonary artery and descending aorta - L to R shunt. normally the ductus arteriosus closes within hrs of birth.
what are the clinical features of a PDA? murmur?
3 classic signs: bounding pulse, ‘machinery murmur’, pulmonary hypertension. also - breathless, poor feeding, failure to thrive, Eisenmenger’s syndrome. murmur = continuous machinery murmur best heard across back
how would you treat a PDA?
indometacin (prostaglandin) can stimulate closure. if large - surgical or percutaneous closure.
what is Eisenmenger’s syndrome?
cyanosis - clubbed and blue toes, pink not clubbed fingers.
what is coarctation of the aorta?
congenital narrowing of the descending aorta
what are the clinical features of coarctation of the aorta? name 2 complications.
radiofemoral delay, weak femoral pulse, high BP, systolic murmur. heart failure + IE.
how would you treat coarctation of the aorta?
surgery or balloon dilation ± stenting
what are the consequences of a biscupid aortic valve?
go on to develop aortic stenosis - requiring valve replacement. higher risk of IE.
give some clinical features of pulmonary stenosis
RV failure as neonate. collapse. poor pulmonary blood flow. RVH. tricuspid regurg.
how would you treat pulmonary stenosis?
ballon valvuloplasty. open vavlotomy.
what are the 4 features of tetralogy of Fallot?
1 - VSD. 2 - pulmonary stenosis. 3 - RVH. 4 - aorta overriding the VSD
what causes tetralogy of Fallot?
abnormalities in separation of truncus arteriosus into the aorta and pulmonary arteries early in gestation
describe the presentation of tetralogy of Fallot
acyanotic at birth. gradually become cyanotic. Fallow (hypoxic) spells - go blue, restless, inconsolable crying - toddlers may squat.
what is the characteristic feature of a CXR in tetralogy of Fallot?
boot shaped heart
how is tetralogy of Fallot managed?
oxygen. knee-chest position. morphine. long-term beta blockers. surgery at less than 12 months.
outline the pathway of normal cardiac conduction
- SA node initiates impulse, spread through atria via internodal pathways. - pause at AVN for depolarisation. then goes down bundle of His to right and left bundle branch. - Left splits into anterior and posterior hemifascicles as well.
what’s the equation for cardiac output?
CO = SV x HR
what’s the equation for blood pressure?
= SVR (systemic vascular resistance) x CO
briefly explain Starling’s law
preload (degree of stretch) = critical factor for SV. increased end-diastolic volume (EDV) leads to increased myocardial stretch. increased myocardial stretch leads to increased contracility, and increased SV –> decreases end systolic volume. so if blood loss, the reduced EDV = reduced CO
where on the chest should you be listening for murmurs?
- mitral area = apex midclavicular line, 5th IC space - tricuspid = inferior right sternal area, 4th IC space - pulmonary = left 2nd IC space, next to sternum - aortic = right 2nd IC space next to sternum
how do you grade murmurs?
scale 1-6 (Levine’s scale) 2 = low intensity, everyone should be able to hear it though 3 = medium intensity, but no palpable thrill 4 = medium intensity with palpable thrill
what action in the heart does each heart sound correspond to?
S1 = closure of mitral and tricuspid valves (M1 + T1) S2 = closure of aortic and pulmonary valves (A2 + P2) - might split on deep inspiration due to delayed P2
give some causes of a third heart sound
might actually just be split S2 (delayed P2 in pulmonary HTN and pulmonary stenosis) in heart failure can 3rd heart sound = gallop rhythm systolic - can be innocent if pregnant/child - heard between S1 and S2 diastolic = always pathological, between S2 and S1