Q. Indications for Surgery of mitral regurgitation?
Surgery is indicated in all symptomatic patients (class II and above) with severe mitral regurgitation and normal or decreased left ventricular function. Surgery is also indicated in an asymptomatic patient with left ventricular ejection fraction less than 60 per cent and or left ventricular end systolic dimension more than 45 mm. In patients with severe mitral regurgitation, even when the patient is asymptomatic, one should not allow left ventricular ejection fraction to fall less then 55 per cent as post operative recovery will not be good. Though left ventricular ejection fraction is a better index to follow than left ventricular end systolic dimension, surgery may be considered even if one of the parameters is satisfied. When left ventricular ejection fraction is less than 30 per cent or end systolic dimension more than 55 mm, mitral valve surgery carries high risk and may not be beneficial. Surgery is indicated in symptomatic or asymptomatic patient with recent onset severe mitral regurgitation and also in patients with atrial fibrillation. With onset of atrial fibrillation patients tend to become symptomatic and left ventricular dysfunction sets in. Atrial fibrillation tends to persistent even after mitral valve surgery if its duration is more than three months. Similarly asymptomatic severe mitral regurgitation patients with pulmonary artery systolic pressure of equal to or more than 50 mm Hg. at rest or equal to or more than 60 mm Hg. with exercise are also candidates for mitral valve surgery. The outcome in patients with ischaemic mitral regurgitation is worse than those with non ischaemic etiology as they have underlying left ventricular dysfunction. In patients with papillary muscle dysfunction due to reversible ischaemia, simple revascularization may be sufficient. Many patients with severe ischaemic mitral regurgitation need mitral valve replacement or repair.