Which heart disorder causes reduced blood flow through the lungs and may lead to anasarca?

The heart disorder that causes reduced blood flow through the lungs and may lead to anasarca is congestive heart failure. In this condition, the heart's ability to pump blood effectively is compromised, leading to a backup of fluid in the lungs, known as pulmonary congestion. When fluid accumulates in the tissues, it can spread throughout the body, resulting in anasarca, which is severe generalized edema.

Congestive heart failure can occur for various reasons, including coronary artery disease, hypertension, or damage to the heart muscle. The resultant fluid overload not only affects the lungs but also causes swelling in the extremities and abdomen due to the increased pressure in the vascular system that results from the heart's inefficiency.

While generalized passive hyperemia involves the accumulation of blood in the vascular system, it does not specifically cause the same fluid retention effects in the lungs and overall body like congestive heart failure does. Other options, such as pulmonary embolism and myocardial infarction, can also impact blood flow but manifest differently and do not typically cause anasarca as a direct outcome.