Q. What is Acute Severe Mitral Regurgitation?

Acute severe mitral regurgitation is a medical emergency. Patient presents with breathlessness and low output state. He may be is shock with extreme dyspnoea. There may be features of background disease that led to mitral regurgitation like coronary artery disease usually an inferior wall myocardial infarction, infective endocarditis, or mitral valve prolapse with chordal rupture. In the absence of time for compensatory left ventricular and left atrial dilatation patient will have an acute decrease in forward output and acute increase in pulmonary wedge pressures leading to pulmonary edema. There will be tachycardia, tachypnoea and extremities may be cold with signs
of left ventricular failure. One should not be looking for signs of chronic mitral regurgitation.

Cardiomegaly is absent and systolic murmur is often short and may even be inaudible. An S3 and often an S4 are audible. Echocardiography is diagnostic and trans thoracic echo may not completely reveal the extent of mitral regurgitation. Trans esophageal echocardiography is required. This will not only show the severity of mitral regurgitation but also uncover the pathology and anatomy of the mitral valve. This is essential to plan type of surgery. Surgery is often mandatory. Medical management includes use of nitroprusside alone or with inotropic agents like dobutamine. Intra aortic balloon pump preeminently decreases the afterload and improves forward output as well as degree of mitral regurgitation. Whenever possible this should be used prior to planned surgery.