What is the most common cause of a heart murmur?

Mitral regurgitation is often regarded as one of the most common causes of heart murmurs due to its prevalence in the general population, particularly in individuals with certain risk factors such as age, rheumatic heart disease, or degenerative valve conditions. In mitral regurgitation, the mitral valve does not close fully during systole, which allows blood to flow backward from the left ventricle into the left atrium. This backward flow generates turbulence in the blood flow, which is what creates the characteristic sound of a murmur when auscultated.

Mitral regurgitation can be found in a wide range of patients, making it a familiar finding during cardiac examinations. It can result from various underlying issues such as valve prolapse, ischemia, or dilation of the left ventricle, thereby contributing to its common occurrence. Clinicians often encounter mitral regurgitation in clinical practice, reflecting its significance in cardiovascular assessments.

This understanding of mitral regurgitation and its frequency aids healthcare providers in diagnosing and managing patients with heart murmurs effectively.