Chronic mitral regurgitation leads to volume overload primarily affecting which chamber?

Chronic mitral regurgitation leads to volume overload primarily affecting which chamber?

• A. Right atrium
• B. Left atrium
• C. Right ventricle
• D. Left ventricle

Answer: (B)

In chronic mitral regurgitation, systolic blood flows backward from the left ventricle into the left atrium. This direct regurgitant influx causes the left atrium to bear the extra volume each heartbeat, leading to progressive dilatation and elevated pressures in the left atrium and the pulmonary circulation. While the left ventricle does experience increased preload as it has to eject blood both to the aorta and back into the atrium, the chamber primarily subjected to volume overload is the left atrium because it is the recipient of the regurgitant flow. The right heart is not the primary site of this volume overload (though it may be affected secondarily if pulmonary pressures rise).

In chronic mitral regurgitation, systolic blood flows backward from the left ventricle into the left atrium. This direct regurgitant influx causes the left atrium to bear the extra volume each heartbeat, leading to progressive dilatation and elevated pressures in the left atrium and the pulmonary circulation. While the left ventricle does experience increased preload as it has to eject blood both to the aorta and back into the atrium, the chamber primarily subjected to volume overload is the left atrium because it is the recipient of the regurgitant flow. The right heart is not the primary site of this volume overload (though it may be affected secondarily if pulmonary pressures rise).