What clinical manifestation is often associated with restrictive cardiomyopathy (RCM)?

In restrictive cardiomyopathy (RCM), one of the hallmark clinical manifestations is dyspnea on exertion. This condition is characterized by the heart's inability to fill adequately due to stiffened ventricular walls. As a result, the heart struggles to accommodate the returning blood from the body and lungs, leading to increased pressures in the left atrium and pulmonary circulation, which can result in congestion.

Patients with RCM often experience exertional dyspnea because physical activity demands increased cardiac output. However, due to the rigid diastolic dysfunction of the myocardium, the heart cannot compensate adequately. This situation results in fluid backing up in the lungs, which contributes to the sensation of shortness of breath during exercise or even at rest as the disease progresses.

While palpitations, chest pain, and fatigue may also occur in patients with RCM, they are not as directly linked to the specific pathophysiology of the condition as dyspnea on exertion is. For example, palpitations could arise from a variety of cardiac issues, including arrhythmias that may not be directly related to the restrictive pattern of filling seen in RCM. Chest pain might be more indicative of ischemia or other cardiac conditions, and fatigue, though common