AL Cardiac Amyloidosis Mimicking Dilated Cardiomyopathy With Reduced Ejection Fraction and Absent Apical Sparing.

BACKGROUND: Amyloid light chain (AL) amyloidosis is a rapidly progressive disease with significant untreated mortality especially when diagnosis is delayed, making early detection of disease crucial. Various cardiac imaging modalities are emerging as alternatives to echocardiography for the early detection of this disease. CASE SUMMARY: A patient presented with progressive heart failure symptoms and was evaluated with an echocardiogram showing a mildly dilated left ventricle, moderate systolic dysfunction, only mildly increased left ventricular wall thickness, and reduced global longitudinal strain without apical sparing. Cardiac magnetic resonance (CMR) showed diffuse, patchy late gadolinium enhancement. Endomyocardial biopsy confirmed AL cardiac amyloidosis (CA). The patient was treated with guideline-directed medical therapy and chemotherapy agents. DISCUSSION: Although echocardiography has great utility as a screening tool for cardiac amyloidosis given its widespread availability, this case highlights its potential limitations and emphasizes the importance of CMR for evaluation of dilated cardiomyopathies and CA detection. TAKE-HOME MESSAGES: CA may present with dilated cardiomyopathy and lack classic echocardiographic features. Early CMR may facilitate timely diagnosis of CA.