A rash with a heavy heart

Area of Science:

• Cardiology
• Nephrology
• Hematology

Background:

• Cardiac amyloidosis (CA) is a rare infiltrative disease often misdiagnosed due to overlapping symptoms with other conditions causing left ventricular (LV) hypertrophy.
• Primary light chain (AL) amyloidosis can present with cardiac involvement, mimicking hypertrophic cardiomyopathy (HCM).

Observation:

• A 49-year-old man with a prior HCM diagnosis presented with periorbital rash, numbness, and shortness of breath.
• Physical exam revealed periorbital purpura, macroglossia, and orthostatic hypotension. Cardiac auscultation noted S3 and S4 sounds.
• Electrocardiography (ECG) showed diffuse low-voltage QRS complexes, and echocardiography demonstrated severe diastolic impairment, a "sparkling" myocardium, thickened cardiac structures, and pericardial effusion.

Findings:

• Laboratory tests revealed elevated free light chain-differential (FLC-diff), N-terminal fragment of brain natriuretic peptide (NT-BNP), and cardiac Troponin T (cTnT).
• Bone marrow biopsy confirmed AL amyloidosis.
• The constellation of clinical, ECG, echocardiographic, and serological findings led to the diagnosis of AL amyloidosis with cardiac involvement mimicking HCM.

Implications:

• This case underscores the critical importance of integrating clinical presentation, serological markers, ECG, and echocardiographic findings for the accurate diagnosis of cardiac amyloidosis.
• Early and accurate diagnosis of cardiac amyloidosis is crucial for timely management and potentially improving patient outcomes.
• Recognizing AL amyloidosis as a mimic of HCM is vital to avoid diagnostic delays and ensure appropriate treatment strategies.