What is the most likely sequela of an arteriovenous fistula located near the heart?

An arteriovenous fistula located near the heart can significantly impact cardiovascular dynamics. Such a fistula creates an abnormal connection between an artery and a vein, leading to increased blood flow in the venous system. This increased volume and velocity of blood can overload the heart, as it must now accommodate a greater circulating blood volume than normal. Over time, this can contribute to congestive heart failure (CHF), where the heart struggles to pump effectively, leading to symptoms such as fluid retention, shortness of breath, and fatigue.

When an arteriovenous fistula is situated close to the heart, it can directly influence cardiac output and pressure, further exacerbating the risk of developing CHF. Therefore, it's logical to conclude that congestive heart failure is the most likely serious consequence of such a vascular anomaly. The other options, while they may have some connection to vascular issues, are less directly associated with the physiological changes induced by an arteriovenous fistula in this specific location.