Cardiac amyloidosis mimicking hypertrophic cardiomyopathy.
Amyloid infiltration of the heart may frequently masquerade as other cardiac disorders. The extended use of echocardiography may contribute to an erroneous diagnosis of hypertrophic cardiomyopathy, as both conditions show several features in common. This was the case with the patient reported below. A low QRS amplitude, an increased right ventricular wall thickness, thickened cardiac valves, and a pericardial effusion may, however, indicate amyloid infiltration. The diagnosis of systemic amyloidosis of immunocytic origin was subsequently established in our patient. A definitive diagnosis of amyloid heart disease requires endomyocardial biopsy, but it is suggested that typical noninvasive findings together with demonstration of amyloid in an organ other than the heart is sufficient for a reliable diagnosis. In addition, systemic manifestations may contribute to a correct diagnosis in generalized amyloidosis. Our patient had features consistent with the rare muscle pseudohypertrophy syndrome, which is associated with immunocytic amyloidosis.