Which symptom is most likely associated with right heart failure in restrictive cardiomyopathy?

In the context of restrictive cardiomyopathy, the most likely symptom associated with right heart failure is fluid retention. This condition is characterized by the inability of the heart to fill properly due to the rigidity of the heart muscle, which leads to diastolic dysfunction. As the right side of the heart struggles to effectively pump blood, it results in elevated pressure in the venous system.

Fluid retention occurs because increased venous pressure can cause fluid to leak from the blood vessels into the surrounding tissues, leading to symptoms such as peripheral edema (swelling in the legs and ankles) and potentially contributing to ascites (fluid accumulation in the abdominal cavity). The kidneys may also retain sodium and water in response to decreased cardiac output, further exacerbating fluid retention.

Pulmonary congestion typically associates more with left heart failure, where fluid backs up into the lungs due to pressure build-up in the pulmonary circulation. Bradycardia and episodes of palpitations, while they might be experienced by some patients, are not as characteristic of right heart failure and may not directly relate to restrictive cardiomyopathy in the same way that fluid retention does. Therefore, fluid retention is the most prominent symptom associated with right heart failure in this scenario.