Under what condition is blood most likely to flow "backward" (e.g. ,from the left ventricle back into the left atrium)?

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Quizplus · Accepted Answer

Blood flowing backward from the left ventricle into the left atrium is called mitral regurgitation or mitral insufficiency. This can occur when the mitral valve, which separates the left atrium and left ventricle, does not close properly. This can be due to a number of reasons, including conditions that cause the valve to become stretched or damaged, such as rheumatic fever or mitral valve prolapse. Left ventricular hypertrophy (B) and pulmonary artery hypertension (A) can increase the pressure within the heart and blood vessels and make it harder for blood to flow forward efficiently, but they do not necessarily cause blood to flow backward. Pulmonary edema (D) is a condition in which fluid accumulates in the lungs, but it does not directly affect blood flow through the heart.

Under What Condition Is Blood Most Likely to Flow "Backward