What is mitral valve prolapse?

What is mitral valve prolapse?

• A. Inflammation of the inner lining of the heart
• B. Dilation of the aorta
• C. Blockage of a coronary artery due to atherosclerosis
• D. Improper closure of the valve between the left atrium and left ventricle due to enlarged or stretched leaflets

Answer: (D)

This item tests understanding of what happens when the mitral valve leaflets become floppy and fail to close properly during systole. Normally, as the left ventricle contracts, the mitral valve leaflets come together firmly to seal off the left atrium and prevent backflow. If the leaflets are enlarged or stretched—often from myxomatous degeneration—they billow backward into the left atrium as the ventricle contracts. This improper closure allows blood to leak from the ventricle into the atrium, which is mitral regurgitation. The description that fits this scenario is the one stating improper closure of the valve between the left atrium and left ventricle due to enlarged or stretched leaflets. In practice, this condition—mitral valve prolapse—can present with a midsystolic click and a late systolic murmur and is sometimes asymptomatic, with potential associations including connective tissue disorders. The other options describe inflammation of the heart lining, dilation of the aorta, or blockage of a coronary artery, none of which involve the mitral valve’s closure mechanism.

This item tests understanding of what happens when the mitral valve leaflets become floppy and fail to close properly during systole. Normally, as the left ventricle contracts, the mitral valve leaflets come together firmly to seal off the left atrium and prevent backflow. If the leaflets are enlarged or stretched—often from myxomatous degeneration—they billow backward into the left atrium as the ventricle contracts. This improper closure allows blood to leak from the ventricle into the atrium, which is mitral regurgitation. The description that fits this scenario is the one stating improper closure of the valve between the left atrium and left ventricle due to enlarged or stretched leaflets. In practice, this condition—mitral valve prolapse—can present with a midsystolic click and a late systolic murmur and is sometimes asymptomatic, with potential associations including connective tissue disorders. The other options describe inflammation of the heart lining, dilation of the aorta, or blockage of a coronary artery, none of which involve the mitral valve’s closure mechanism.