Light-Chain (AL) Cardiac Amyloidosis Presenting as Heart Failure With Reduced Ejection Fraction.

Systemic amyloidosis is caused by the extracellular deposition of misfolded proteins in various organs and usually leads to organ dysfunction. The two common subtypes include light-chain amyloidosis and transthyretin amyloidosis. Deposition of these proteins in the heart can lead to infiltrative and restrictive cardiomyopathy, commonly manifesting as heart failure with preserved ejection fraction. However, systolic heart failure with reduced ejection fraction is mainly seen in the advanced stages of the disease. Here, we present the case of a 53-year-old female who presented with new-onset heart failure with reduced ejection fraction with no prior symptoms or diagnosis of amyloidosis and diastolic dysfunction.