Most common cause of death in primary amyloidosis is?

ANSWER: (B) Cardiac failureREF: Harrison's Internal Medicine 17th edition chapter 324. AmyloidosisThe kidneys are the most frequently affected organ (80%), Renal amyloidosis is usually manifested by proteinuria, which is often in the nephrotic range and associated with significant hypoalbuminemia and edema or anasarca; rarely, tubular rather than glomerular deposition of amyloid can produce azotemia without significant proteinuria. Cardiac symptoms are the second most common presentation (40%), but cardiac dysfunction is associated with death in 75% of patients.