Mitral Regurgitation

Introduction

Mitral regurgitation refers to leaking of the mitral valve during systole such that blood returns to the left atrium from the left ventricle.

Murmur

Sound: Pansystolic murmur

Loudest region: Mitral area (5th intercostal space, mid-clavicular line)

Radiation: Axilla

Accentuation: Expiration

Pansystolic murmur. Source: University of Michigan Murmur library

Causes

Acute disease

• Infective endocarditis
• Myocardial infarction (rupture of chordae tendineae)

Chronic disease

• Rheumatic fever
• Connective tissue disease
• Mitral valve prolapse
• Congenital abnormality

Functional disease

Functional regurgitation occurs due to a left ventricular abnormality, such as abnormal shape, rather than mitral valve pathology.

• Hypertension
• Ischaemic heart disease
• Dilated cardiomyopathy

Differential diagnosis

• Ventricular septal defect
• Tricuspid regurgitation

Investigations

• Echocardiogram
• ECG: may show atrial fibrillation and p-mitrale (broad, bifid P waves)
• Chest x-ray
• Blood cultures, if considering infective endocarditis

Management

Medically manage underlying heart failure and atrial fibrillation.

Surgical management should be offered to symptomatic patients or those with a reduced ejection fraction.