right heart valve disease Flashcards
What is the pathophysiology of mitral stenosis
recurrent inflammation causes damage over time
Valve narrows due to damage, flow across left atrium to left ventricle is reduced, increased pressure in LA, congesting pulmonary circulation,
Chronic congestion of blood in LA can cause dilatation, can lead to AF or thromboembolism.
What is mitral stenosis
narrowing of the mitral valve orifice that occurs due to fusion of leaflet commisures
What are the main causes of mitral stenosis?
Rheumatic fever most common cause worldwide but not uk
In Uk it is ageing (degenerative calcification of leaflets), or congenital valve deformity.
How does mitral stenosis present?
Dyspnoea, fatigue, AF, haemoptysis (blood cough)
On examination, low volume pulse, flushed cheeks, irregularly irregular pulse (AF), tapping apex beat,
How does mitral stenosis present upon auscultation
loud first heart sound, opening snap rumbling mid diastilic murmur
WHat are the investigations for mitral valve stenosis?
Trans thoracic echocardiogram
ECG
CXR
How is mitral valve stenosis managed?
Anticoagulants given if AF or previous embolic events,
Diuretics reduce dyspnoea and right heart failure, beta blockers reduce heart rate and optimise cardiac output
Valve intervention is the most effective. Indicated in severe stenosis, and pulmonary hypertension. Includes percutaneous mitral balloon commissurotomy (PMBC) as first line, surgical repair or PMBC again, if unsuccessful, valve replacement.
What is mitral regurgitation?
Backflow of blood from the left ventricle to the left atrium as a result of a leaky mitral valve.
What are the main causes of mitral regurgitation?
Acute: papillary muscle infarction, ruptured chordae tendinae, acute rheumatic fever, IE, trauma
Chronic:
Primary:
Mitral valve prolapse (developed countries) rheumatic fever (developing countries)
Mitral valve calcification, congenital abnormalities, CTDs.
Secondary:
LV remodelling/dilation distorts vascular apparatus
What is the pathophysiology of mitral regurgitation?
Backflow into the left atrium decreases CO. Increase in left atrial pressure, left atrial dilatation, volume loading of LV. Regurgitant blood flows into left ventricle.
Acutely,Haemodynamic instability, pulmonary oedema
Chronic: Compensatory mechanisms.
When LV pumps, some goes back into the LA, and back in left atrial systole. Both LV and LA experience hypertrophy. Mitral valve experiences tstructural changes nearby. Big baggy eccentric hypertrophic ventricle and atrium, poor job, less blood empties, back pressure into lungs and arteries. Dyspnoea, CHF, AF.
What are the clinical features of acute mitral regurgitation?
Acute: Emergency, sudden onset severe dyspnoea, rapidly progressive pulmonary oedema, hypotension and cardiogenic shock
What are the clinical features of chronic mitral regurgitation?
Asymptomatic if mild/moderate
Symptoms happen when left heart failure develops in severe MR. Dyspnoea on exertion, fatigue. AF. risk of IE
What does mitral regurgitation show on examination including auscultation?
AF, displaced apex beat, auscultation yeilds a 3rd heart beat sometimes, and blowing pansystolic murmur radiating to axilla
What investigations are undertaken for mitral regurgitation?
Echocardiography and doppler, ECG, CXR
Second line is cardiac catheterisation.
How is mitral regurgitation managed?
Acute:
Medical and surgical emergency, inotropes and intra-aortic balloon pumps if life threatening, nitroprusside to reduce MR. Surgery is mitral valve repair.
Chronic: Anticoagulation (warfarin should be given if patient has had AF, or previous embolic event). Target INR is 2.50-
