Cardiac amyloidosis: A diagnostic challenge

Abstract

Cardiac amyloidosis is indeed a condition characterized by the deposition of amyloid proteins in the myocardium, leading to thickening and stiffening of the heart muscle. These abnormal protein deposits can interfere with the heart's normal functioning and may pose diagnostic challenges due to its varied clinical presentation and resemblance to other heart condition. Here, we present a case of 55-year-old female patient of uncontrolled hypertensions for 15 years. About 15 years ago, she presented with chest pain and was diagnosed with cardiomyopathy (CM) characterized by low left ventricle (LV) function of unknown cause. Despite being on antihypertensive treatment, the patient continued to experience chest heaviness with persistent elevate blood pressure. An echocardiogram revealed increased LV septal wall thickness, valvular thickening, and biatrial dilation. Subsequently, cardiac magnetic resonance imaging (CMR) was performed, which revealed left atrium enlargement and asymmetrical myocardial wall thickening, particularly at the septum. White blood axial image revealed thickened inter atrial septum, while late gadolinium enhancement (LGE) magnetic resonance (LGE MR) images showed patchy LGE at the base relative to the apex of the myocardium, highlighting the base-to-apex gradient, subendocardial pattern enhancement at apical lateral wall, and transmural pattern enhancement of the mid anteroseptal and inferoseptal wall. Additionally, a short axis time to invert T1 scout image of left ventricle displayed an abnormal nulling pattern initially in the myocardium, followed by the blood pool, and finally the spleen. These findings collectively led to the diagnosis of cardiac amyloidosis.

Keywords

• Cardiac amyloidosis
• Transthyretin amyloid cardiomyopathy (ATTR-CM)
• Cardiac magnetic resonance (CMR)
• Late gadolinium enhancement (LGE)
• Postcontrast invert T1 scout images Abnormal nulling pattern (ANP)