mitral regurg Flashcards
1
Q
definition
A
retrograde blood flow from LV to LA during systole
2
Q
causes
A
- most common- rheumatic heart disease
- IE
- MVP [mitral valve leaflets prolapse during systole]
- Pap muscle rupture/chordal rupture ==> post MI
- floppy mitral valve- due to conn tissue disease eg. E-D, Marfans
- annular calcification -> elderly
- functional MR 2ry to L ventricle dysfunction
3
Q
s/s
A
symptoms
- dyspnoea
- fatigue
- AF- palpies
- pulm congestion- HTN + oedema
- acute MR- LVHF symptoms
- chornic MR- above symptoms
- MVP- asympto/atypical chest pain/palpies
signs
- pulse may be irreg irreg
- L parasternal heave
- apex- laterally diseplaced, thrusting
- heart sounds- soft S1, SPLIT S2
- murmur- blowing pansystolic murmur, radiates to axilla [palpable as a thrill]
4
Q
ix
A
BLOODS: FBC, U+E, glucose, lipids
CXR: may show cardiac enlargement
ECG: AF, LVH, broad bifid p waves [p mitrale]
echocardiography: every 6-12 mo, for mod severe MR, assesses LV ejection fraction
cardiac catheterization: quantitates the gradient across the valve
5
Q
MX- MEDICAL, SURGICAL, ACUTE, CHRONIC
A
MEDICAL RX:
- atrial fibrillation controlled with digoxin.
- if left ventricular failure occurs the this is treated with diuretics and ACE inhibitors.
- prophylaxis against infective endocarditis.
- systolic hypertension is treated because it increases mitral regurgitation.
- anticoagulation if there is atrial fibrillation or a dilated left atrium.
SURIGCAL RX:
- Indications for surgery are symptoms - particularly dyspnoea - and severe mitral regurgitation confirmed by echocardiography and angiocardiography. Poor left ventricular function may preclude surgery.
- surgical technique
- rigid or calcified valve: mitral valve replacement, with the advantage that the valve is immediately competent but the disadvantage that the mitral valve disease is replaced with prosthetic valve disease plus risk of anticoagulant related bleeding.
- mobile valve: mitral valve repair.
- results - mortality is higher in valve replacement (6%) than valve repair (2%).
Management of acute aortic or mitral regurgitation involves:
- identification of the problem
- medical stabilisation with diuretic and vasodilator (reduce the afterload and thus the regurgitant volume)
- urgent valve replacement
Management of chronic disease:
- conservative for mild or moderate disease
- valve surgery - repair, valvotomy or replacement in severe disease
- warfarin anticoagulation for mitral stenosis and mitral regurgitation if there is atrial fibrillation or dilated left atrium - larger than 5 cm on echo
- diuretic if required
- digoxin in atrial fibrillation
- antibiotic prophylaxis to prevent endocarditis
- Note that surgery must be undertaken before the left ventricle dilates to an end systolic dimension of 5.5cm or more. If this has occurred then there is a reduction in prospects for recovery of left ventricular function.
- Vasodilator therapy in aortic regurgitation:
- (including hydralazine, calcium-channel blockers, and angiotensin-converting enzyme inhibitors) has been employed in patients with asymptomatic chronic aortic incompetence
6
Q
COMPLICATIONS
A
- ventricular ectopics - these are common, but ventricular tachycardia, fibrillation and sudden death are rare.
- atrial fibrillation - this occurs with increasing age and left atrial enlargement.
- thrombo-embolism - this is a rare complication.
- infective endocarditis - this occurs more frequently with mild mitral regurgitation than with any other lesion (approx. 5%).
- chordal rupture - this occurs in a small proportion of patients with prolapsing valves. This condition causes a sudden increase in mitral regurgitation and left ventricular failure which is often transient.
- pulmonary hypertension - this is less common in mitral regurgitation than mitral stenosis. It is more frequent in patients with small left atria.
7
Q
PROGNOSIS
A
depends on aetiology + state of LV function
acute MR= due to cusp/pap muscle rupture == poor prog
rheumatic MR may slowly deteriorate over 10-20yrs…
