We report the M-mode and two-dimensional echocardiographic findings in a patient with familial amyloidosis. The diagnosis was made by the clinical picture and histologic evidence of amyloid in peripheral nerve biopsy. Though the patient had no clinical sign of heart failure, extensive involvement of the heart was demonstrated by echocardiography. M-mode echocardiography revealed increased right ventricular wall thickness in conjunction with symmetric increase in left ventricular wall thickness. On two-dimensional echocardiography, the entire interventricular septum and the papillary muscles were more dense than normal. These high density echoes had a "granular and sparkling" pattern. This case shows that cardiac amyloidosis can be diagnosed in the pre-clinical, asymptomatic state by M-mode and two-dimensional echocardiography. When symptomatic, confusion with constrictive pericarditis may be avoided non-invasively.