Echocardiographic features in familial amyloidosis with polyneuropathy.

Twenty-two patients with the Swedish variant of familial amyloidosis with polyneuropathy were studied by M-mode and two-dimensional echocardiography. These patients had few symptoms consistent with cardiac disease but, nevertheless, echocardiograms of only two of them, both with a short history of the disease, were considered normal in all aspects. The most common abnormality was increased thickness of the interventricular septum found in 20 (91%) of the patients. This septal hypertrophy was asymmetric in 12 (55%) of them. Two-dimensional echocardiography revealed a characteristic hyperrefractile appearance of the myocardium in 15 (68%) of the patients. Thus, echocardiography showed a characteristic pattern in these patients. This study also indicates that cardiac amyloidosis can be diagnosed in the preclinical, asymptomatic state by M-mode and two-dimensional echocardiography.