Atrioventricular and intraventricular conduction in familial amyloidosis with polyneuropathy.

Atrioventricular and/or intraventricular conduction disturbances were found in 48 (67%) out of 71 patients with familial amyloidosis with polyneuropathy. Low voltage, often described in various forms of heart amyloidosis, was seen in one patient only. Myocardial infarction patterns, also often reported in heart amyloidosis, were not present in our patients. The prevalence of conduction disturbances increased with the duration of the disease. In 28 out of 47 patients from whom more than one ECG recording was available, a progression of conduction disturbances could be seen. Ten patients developed high-degree conduction disturbances and required permanent pacemaker treatment.