MR

Question 1

definition of MR

Answer 1

Retrograde flow of blood from LV to left atrium through the mitral valve during systole.

Question 2

aetiology of MR

Answer 2

rheumatic heart disease

infective endocarditis

mitral valve prolapse - into LA in systole

papillary muscle rupture or dysfunction - secondary to ischemic heart disease or cardiomyopathy

chordal rupture and floppy mitral valve associated with connective tissue diseases(e.g. pseudoxanthoma elasticum, osteogenesis imperfecta, Ehlers–Danlos syndrome, Marfan syndromes, SLE).

annular calcification - elderly

congenital

appetite suppressants - fenfluramine, phentermine

Functional mitral regurgitation may be secondary to left ventricular dilation.

Question 3

epidemiology of MR

Answer 3

affects 5% adults

mitral valve prolapse is more common in young females

Question 4

sx of MR

Answer 4

acute MR - symptoms of LV failure

chronic - asymptomatic, exertional dyspnoea, palpitations of in AF and fatigue

Mitral valve prolapse: Asymptomatic or atypical chest pain or palpitations.

dyspnoea

symptoms of causative factor eg fever

Question 5

signs of MR

Answer 5

pulse may be normal/irregularly irregular - AF

Apex beat may be laterally displaced and thrusting (left ventricular dilation).

Pansystolic murmur, loudest at apex, radiating to axilla (palpable as a thrill). S1 is soft; S3 maybe heard (rapid ventricular filling in early diastole), S2 split, loud P2 (pul hypertension)

Signs of left ventricular failure in acute mitral regurgitation.

Mitral valve prolapse: Mid-systolic click and late systolic murmur. The click moves towards the first heart sound on standing and moves away on lying down.

the more severe - the louder the ventricle

Question 6

ix for MR

Answer 6

ECG

CXR

echo

cardiac catheterisation

Question 7

ecg for MR

Answer 7

normal

AF

broad bifid p wave (p mitrale) if in sinus rhythm - indicating delayed activation of LA due to atrial enlargement

LVH

Question 8

CXR for MR

Answer 8

acute = signs of LVF

chronic = LA and LV enlargement, cardiomegaly (caused by L ventricular dilation) or mitral valve calcification in rheumatic cases

pul oedema

Question 9

echo for MR

Answer 9

Every 6–12 months for moderate–severe MR to assess the LV ejection fraction and end-systolic dimension.

To assess LV function and MR severity and aetiology (transoesophageal to assess severity and suitability for repair rather than replacement).

Question 10

cardiac catheterisation for MR

Answer 10

confirm diagnosis, exclude other valve disease, and assess coronary artery disease (can combine CABG with valve surgery).