Mitral Regurgitation II: Clinical Features and Diagnostic Tests

Acute mitral regurgitation presents suddenly with severe dyspnea, hypotension, tachycardia, and cardiogenic shock, often from myocardial infarction or valve rupture. Chronic mitral regurgitation develops gradually and may remain asymptomatic for years, eventually progressing to weakness, fatigue, palpitations, orthopnea, and peripheral edema as left ventricular failure advances.

A holosystolic murmur at the apex radiating to the left axilla is the characteristic finding for mitral regurgitation. The murmur is described as a blowing sound best heard with a stethoscope. In chronic cases, additional signs include a third heart sound (S3), peripheral edema, and cool, clammy extremities indicating systemic hypoperfusion.

Echocardiography is the most valuable diagnostic tool for mitral regurgitation, assessing regurgitation severity, valve anatomy, and ventricular function. It provides detailed visualization of how the mitral valve fails to close tightly and allows blood to leak backward into the heart, guiding clinical decision-making and treatment planning.

Cardiac MRI provides detailed images of the mitral valve and surrounding cardiac structures, complementing echocardiography findings. This imaging modality helps assess valve anatomy and ventricular function, offering additional anatomical information useful for comprehensive evaluation and surgical planning in mitral regurgitation cases.

An electrocardiogram can reveal atrial fibrillation and other rhythm abnormalities associated with advanced mitral regurgitation. These arrhythmias develop as the left atrium dilates from chronic blood backflow, and detecting them is important for comprehensive cardiac assessment and determining appropriate management strategies.

Chronic mitral regurgitation initially causes fatigue, dyspnea, and palpitations. As disease progresses, symptoms advance to orthopnea (shortness of breath when lying flat) and paroxysmal nocturnal dyspnea (sudden nighttime breathing difficulty). Peripheral edema and other signs of left ventricular failure eventually develop as the condition worsens.

Comprehensive patient history collection is the foundation of mitral regurgitation assessment, identifying symptom onset, progression, and severity. History helps distinguish acute from chronic presentations and reveals risk factors like myocardial infarction or valve degeneration, guiding physical examination focus and determining which diagnostic tests are most appropriate.