Cardiac amyloidosis: new insights into diagnosis and management.

When amyloidosis affects the heart, a devastating and progressive process can lead to congestive heart failure, arrhythmias, conduction abnormalities, angina, and death. The signs and symptoms of cardiac amyloidosis are generally dominated by diastolic heart failure resulting from restrictive cardiomyopathy. Amyloid infiltration of the heart initially causes mild diastolic dysfunction, but late disease produces a thickened heart wall with a firm and rubbery consistency, which worsens cardiac relaxation and diastolic compliance. Patients usually complain of progressive dyspnea from congestive heart failure, chest discomfort secondary to microvascular involvement, and weight loss, which might be a manifestation of cardiac cachexia. Echocardiographic findings include nondilated ventricles with concentric left ventricular thickening, right ventricular thickening, prominent valves, dilated atria, and thickening of the interatrial septum. Recent advances in our understanding of the pathophysiology of amyloid have allowed the various types to be differentiated, which has led to targeted therapy for each unique pathophysiologic process.