Structural Heart Disease 2 Flashcards
Are ventricular and atrial septal defects congenital or acquired
Congenital
what is coarctation of the aorta?
congenital narrowing of the aorta → pinching effect at curve point
what is the tetralogy of Fallot?
ventricular septal defect, pulmonary stenosis, right ventricular hypertrophy and overriding aorta all occurring together (congenital)
what is overriding aorta?
congenital heart defect → aorta placed over a ventricular septal defect → transports some deoxygenated blood from right ventricle to the rest of the body
examples for valvular defects
mitral/aortic stenosis/regurgitation
difference between stenosis and regurgitation?
stenosis = stiffening, can’t open fully. regurgitation = can’t close fully, leads to backflow
aortic sclerosis vs aortic stenosis?
sclerosis precedes stenosis. = valve thickening but without flow restriction
how to confirm aortic stenosis?
suspected by ejection systolic heart murmur, confirm by echocardiography,Doppler echo for pressure gradient
Aortic stenosis risk factor
hypertension, high LDL levels, smoking, chronic kidney disease, elevated c reactive protein ,radiotherapy,old age,congenital bicuspid valves
Causes of aortic stenosis
rheumatic heart disease, calcium build up, congenital heart diseases e.g. malformed valves
consequences of stenotic valve → pathophysiology?
Degeneration (old age)/congenital malformed valves cause wear and tear of valves//untreated group A streptococcus untested causes antibodies to attack valves—>fibrosis and calcification of aortic valve—>
left ventricle has to contract harder → LV myocardial hypertrophy over time → becomes stiff and harder to fill → pressure overload backs up and causes left atrium dilation → lung pressure up and pulmonary congestion
Symptoms of stenosis valve
syncope due to lack of blood flow to brain on exertion, dyspnoea & crackles on lung auscultation due to pulmonary congestion, angina on exertion due to less coronary artery flow (hypertrophic heart muscles and less perfusion
Management of stenotic valve
Aortic valve replacement
Via surgical valve prosthesis and trans catheter valve replacement
what is aortic regurgitation + subtypes?
diastolic leakage of blood from aorta into ventricles. can be acute (sudden onset pulmonary oedema, hypotension, cardiogenic shock) or chronic (eventually congestive cardiac failure)
Occurs due to incompetence of valve leaflets resulting from intrinsic valve disease or dilation of aortic root
Causes of aortic regurgitation
split into root dilatation and inflammation of valvular endocardium
rheumatic heart disease, aortic valve stenosis, infective endocarditis, congenital heart defects,congenital bicuspid valves
marfan’s syndrome (root dilatation), connective tissue disease (root dilatation),idiopathic,ankylosing spondylitis ,traumatic
Pathophysiology of aortic regurgitation
Marfans (aortic root dilation)/untreated group A streptococcus/congeital (inflammation of valvular endothelium)—>valve leaflets close poorly when aortic pressure is higher than LV during diastole causing back flow of blood—>acute dilatation as increases in stroke volume or chronically LV dilated and eccentricity hypertrophies to accommodate increase in volume—>systolic heart failure as excessive stretching weakened myocardium
Symptoms of aortic regurgitation
diastolic murmur, louder S3, angina on exertion and fatigue, diffuse crackles on lung auscultation, bounding/corrigan pulse,pulmonary congestion
Investigation of aortic regurgitation
echocardiography → can see presence and severity of aortic regurgitation
Main cause of mitral stenosis
rheumatic fever (in developing countries)
Leads to pulmonary hypertension and right heart failure as disease progresses
Mitral stenosis Pathophysiology
valve thickening due to fibrous deposition and calcification e.g. from inflammatory causes and chordae tendinae shortening → obstructed blood flow through mitral valve → impaired emptying of left atrium and filling of LV → more back pressure in left atrium and lungs, less cardiac output and stroke volume leading to congestive heart failure->increase in RV pressure leads to hyoertrophy of right ventricle so right sided heart failure
Signs and symptoms of mitral stenosis
atrial fibrillation bc stretch of atrial conduction fibres, mid diastolic murmur (turbulent blood flow), right sided cardiogenic shock/congestive heart failure, dyspnoea,left atrial enlargement causes compression of surrounding structures
May see dysphagia,haemoptysis
Management of mitral stenosis
if asymptomatic none needed, if symptomatic → diuretic, balloon valvotomy, valve replacement and b blockers
Mitral regurgitation
inappropriate backflow of left ventricle blood into left atrium
Causes of mitral regurgitation
Acute:mitral valve prolapse, infective endocarditis, rheumatic heart disease,prosthetic mitral valve dysfunction
Chronic:SLE, hypertrophic cardiomyopathy,scleroderma,drug related
Pathophysiology of mitral regurgitation
number of causes lead to structural defects in the mitral valve → improper closing → backflow and increase of volume and pressure in left atrium → increased volume pushed into LV in next diastole → LV dilation and decrease in function → decreased cardiac output = congestive heart failure + increased back pressure in lung vasculature = congestion
Signs and symptoms of mitral regurgitation
holosystolic murmur, S3 heart sound, serum creatinine up due to kidney damage, peripheral oedema, O2 sat decrease and tachypnoea, wheeze & crackles
- transthoracic echocardiography, ECG, CXR
Possible investigation of mitral regurgitation
transthoracic echocardiography, ECG, CXR
Management of mitral regurgitation
acute severe: replace and repair valve structures. chronic asymptomatic nothing but chronic symptomatic = surgery
types of cardiomyopathy?
dilated, hypertrophic, restrictive
consequence of dilated cardiomyopathy?
ventricular dilatation and thin walls leads to systolic dysfunction and heart failure and hypokinesis
Causes of dilated cardiomyopathy
myocardial ischaemia, heart valve defects, familial/inherited, myocarditis, alcoholism, thyroid disease, autoimmune disorders, drug ingestion,pregnancy (perioartum cardiomyopathy)
- inflammatory/toxic damage and death of myocytes → enlargement of LV without corresponding myocardial mass increase → gradual overdistention → systolic dysfunction → cardiac output down → volume overload and congestive heart failure
Pathophysiology of dilated cardiomyopathy
inflammatory/toxic damage and death of myocytes → enlargement of LV without corresponding myocardial mass increase → gradual overdistention → systolic dysfunction → cardiac output down → volume overload and congestive heart failure
Signs and symptoms of dilated cardiomyopathy
dyspnoea & pulmonary congestion (crackles), cold extremities, displaced apex beat, fatigue, angina, peripheral oedema
Management of dilated cardiomyopathy
consider underlying cause, then symptomatic treatment e.g. arrhythmias and thrombotic events, diet modification etc
Use SGLT2 before any medication
Heart failure therapy-ACEi,beta blockers,mineralcorticoid receptor agonists
Diuretic for fluid overload
Anticoagulant fir a fib
Cardiac resynchronization therapy/cardioverter defibrillator or LVAD while waiting for transplant
what is hypertrophic cardiomyopathy?
increase in LV wall thickness not solely explained by abnormal loading
Caused by missense mutation in 1 of @0 genes that code for proteins of cardiac sarcomere
Cause of hypertrophic cardiomyopathy
genetic → often autosomal dominant
Pathophysiology of hypertrophic cardiomyopathy
thickening of LV myocardium, frequently involves interventricular septum causing disruption in left ventricular outflow tract→ disorganised myocytes possibly with diffuse interstitial/focal replacement fibrosis → signal conduction disrupted → ventricular arrhythmias → sudden cardiac death
Signs and symptoms of hypertrophic cardiomyopathy
S4, syncope, fatigue, angina, pulmonary congestion & oedema, systolic murmur (interventricular septum involvement narrows the outflow tract), sudden cardiac death
Management of hypertrophic cardiomyopathy
Based on symptoms
If have atrial fibrillation:electrical/oharmalogical defibrillation,anticoagulant therapy
Non obstructive and LVEF >50 then give beta blockers,calcium channel blockers such as verapamil or diltiazem,disopyramide (anti arrhythmic) or diuretic
Or if <50 give b blocker,ACEi/ARB,MRA,diuretic if resistant then do heart transplant,cardiac resynchronisation,ventricular assist device,heart transplant
If obstruction then b blocker,verapamil or dilitazem,disopyramide or cibenzoline or surgery,PTSMA,pacing therapy
what is restrictive cardiomyopathy?
diagnosed if restrictive ventricular filling pattern is established
Causes of restrictive cardiomyopathy
idiopathic, familial(troponin I or desmin mutation), various systemic disorders such as sarcoidosis,haemochomostasis,amyloidosis,fabrys,previous radiation
Pathophysiology of restrictive cardiomyopathy
infiltrative cardiomyopathy = deposition of abnormal substances into heart wall tissue → endomyocardial fibrosis → ventricular wall stiffening → diastolic dysfunction → atrial enlargement → conduction abnormalities and diastolic heart failure due to restriction → eventually adverse remodelling and systolic dysfunction
Signs and symptoms of restrictive cardiomyopathy
ascites and pitting oedema, S4, hepatomegaly, venous pressure up, easy bruising and weight loss (all mostly due to right heart failure from increased venous pressure)
Management of restive cardiomyopathy
heart failure medication e.g. ACE inhibitors, diuretics. antiarrhythmic therapy, pacemaker,immunosuppresion via steroids,transplant
Management of aortic regurgitation
Aortic valve replacement
Acute AR is a medical emergency so replace valve immediately
Asymptomatic pt with chronic severe AR give vasodilators therapy to improve haemodynamics reducing the need for aortic valve replacement
Treat rheumatic fever and infective endocarditis
Mitral stenosis aetiology
Rheumatic fever
Carcinoid symptoms
Use of ergot/sertogeneric drugs,SLE,mitral annular calcification due to ageing,amyloidosis,rheumatoid arthritis,whipple disease,congenital deformity of the
valves cause wear
RRAWCCUMS
Investigation of mitral stenosis
ECG
Chest X ray
Trans thoracic echo
Difference in signs of right heart and left heart failure
Right heart -peripheral Oedema eg leg swelling and raised jugular venous pressure
Left heart failure-pulmonary Oedema
