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 (concentric) 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
Ejection systolic murmur crescendo decrescendo
Management of stenotic valve
Aortic valve replacement
Via surgical valve prosthesis and trans catheter valve replacement
For severe AR only
Currently surgical have mechanical and bio prosthetic valves available
For minimal surgery use bio prosthetic
For transcatheter use bio prosthetic
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 bounding/corrigan pulse,pulmonary congestion
ACUTE-cardio genetic shock tachycardia cyanosis pulmonary Odema and diastolic murmur
Chronic
Wide pulse pressure
Corrigan pulse
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 opening snap (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
Severe asymptomatic. No therapy usually but can get adjuvants balloon valvotomy
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 , following valvular surgery
Chronic:SLE, hypertrophic cardiomyopathy,scleroderma,drug related,rheumatic heart disease
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, O2 sat decrease and tachypnoea, wheeze & crackles and frothy sputum
Signs of CHF
dyspnoea
Possible investigation of mitral regurgitation
transthoracic echocardiography, ECG, CXR,cardiac mri/ct
Management of mitral regurgitation
acute severe: replace and repair valve structures eg a prosthetic ring can be inserted to reshape the valve 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
Idiopathic
Genetic
Toxins alcohol chemo
Pregnancy (peripartum cardiomyopathy)
Viral infections (myocarditis)
Tachycardia related cardiomyopathy
Thyroid disease
Muscular dystrophy
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
Echo shows dilated left ventricle with reduced systolic fraction and global hypokinesis
Syncope
A fib
Palpitations
Can lead to heart failure
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
Ajoritt pt are asymptomatic but some may experience dyspnea
Angina
Syncope
Death from, cardiac causes
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,carcinoid syndrome,scleroderma,anthracycline toxicity
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),palpitations,sob,
Biopsy’s may show non caseating granulomas
Management of restive cardiomyopathy
heart failure medication e.g. ACE inhibitors, diuretics, aldosterone inhibitors
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
Mitral regurgitation aetiology
Acute
Rheumatic heart disease
Infective endocarditis
Mitral valve prolpase
Prosthetic mitral valve dysfunction
After valvular surgery
Chrinuc
Rheumatic heart disease
SLE
scleroderma
Hypertrophic cardiomyopathy
Drug related
Infective endocarditis
Infection of the endocardium which affects the heart valves
Bacteria enter blood stream and form vegetation (bacteria platelets and fibrin)
Most commonly due to streptococcus
How do you diagnose infective endocarditis/symptoms
Revere
Malaise
Sweats
Unexplained weight loss
New heart murmur
Anaemia
Raised infection marker
Echo shows vegetation abcess valve perforation or dehiscence of prosthetic valve
Regurgitation of affected valve often seen
Transoesophegal ech has a higher sensitivity than transthroacic
Features of heart decompensation
Shortness of breath
Frequent coughing
Swelling of legs and abdomen
Fatigue
Raised JVP lung cracked and odema
May also have vascular and emboli phenomena stroke janeway lesion,splinter/conjunctival haemorrhages
Immunological phenomena oslers nodes or roth spots
Decompensation is where heart can’t maintain adequate circulation
What part of the heart does infective endocarditis affect
Endocardium esp valves
Aortic most commonly affected
Aortic>mitral>right sided valves
Bacteria will attach to places where more damage is present thus occurs more frequently at sites of turbulent flow such as valves
How are IV drug users affected by infective endocarditis
Increased risk as bloodstream is exposed to bacteria
More common in those that are immunosuppressed or have congenital heart defects
Dental surgery increases the risk as well
RHD vs rheumatic fever
Rheumatic fever is temporary inflammation caused by group A streptococcus
This affects the connective tissue in the heart and else where
RHD is a permanent condition following RF, there’s a lag between the two from 7-30 years
What is the most common valve dysfunction by rheumatic heart disease
Mitral stenosis
Can affect aortic valve causing regurgitation and then stenosis
Can also affect tricuspid valve
Mitral stenosis clinical signs and symptoms
Fluid overload
Peripheral odema
Malar flush
Hoarse voice due to compression of left recurrent laryngeal nerve by dilated left atrium
Loud s2
RV heave
Haemoptysis fatigue SOB paroxysmal nocturnal dyspnoea palpitations
Palpitations due to a fib
Jones criteria
Used to RHD
evidence of preceding group A streptococcal infection
Major criteria
Carditis
Arthritis
Chorea
Erythema marginatum
Subcutaneous nodule
Minor criteria
Polarthralgia
Fever >38.5
Elevated CRP/ESR
Prolonged PR interval
Need 2 major criteria OR 1 major and 2 minor OR 3 minor
Pathognomic features of rheumatic heart valves
Leaflet or chordal thickening
Prolapse of leaflet
Excessive leaflet tip motion during systole
due to initial inflammatory process of acute rheumatic fever affecting connective tissue of valves
Mitral stenosis management for rhd
Valve commissurotomy (separation of fused commisured which is where leaflets meet)
Valve replacement
Manage complications eg heart failure and a fib use vit k antagonist
If there is no annular calcification then we can replace valve easily but if there is delay until pt becomes severely symptomatic
When do we do PMC
Percutaneous mitral commisuratomy
If there is moderate to severe mitral stenosis MVA <1.5
In symptomatic patients eg fatigue
No significant mitral regurgitation
Done when there no annular calcification then
Dukes criteria for infective endocarditis
Major criteria
Persistent positive blood culture
ECHO:vegetation,dehiscence of prosthetic valve abcess
New valvular regurgitation murmur
Coxiella burnetti infection
Minor criteria
Predisposing heart condition or IV drug use
Fever greater than 38
Vascular:embolism to organs and Braun
Immunological:glomeruloneohritis,oslers node,roth spots
Postive blood cultures that don’t meet specific criteria
**definitive endocarditis **
2 major criteria
1 major 3 minor
5 minor
+ gram stain or culture from surgery or autopsy
possible endocarditis
1 major and >1 minor
3 minor
rejected endocarditis
Resolution after less than 4 days abx
No evidence of infection after surgery
Define or possible criteria not met
