Most common cause of death in primary amyloidosis is

Primary amyloidosis: (light chain amyloidosis or AL-amyloid disease)Primarily a consequence of plasma cell disordersThe kidney is the most frequently involved organ(80%)Hea is second most frequently involved(40%)Cardiac failure is the most common cause of deathCardiac amyloidosis mostly manifests as restrictive cardiomyopathy(ref: Harrison's 18/e p948)