We investigated the occurrence of ventricular late potentials (LPs) in patients with familial amyloidotic polyneuropathy (FAP) and the possible association with ventricular arrhythmia on Holter electrocardiography and echocardiographic data. Fifty-five patients and 94 healthy controls were studied. LP were found in 46% of the FAP patients older than 60 years and in 15% of the controls (P = .02), whereas no difference was found in individuals younger than 60 years. The occurrence of LP was associated with nonsustained ventricular arrhythmia in the older FAP patients (P = .04). Older patients with LP had increased ventricular septum thickness (P = .02) and left posterior wall thickness (P = .01), as compared with those without LP. In conclusion, ventricular LPs are common in the FAP patients older than 60 years and associated with nonsustained ventricular arrhythmia and increased thickness of the left ventricular wall. Long-term follow-up studies are required to find the prognostic significance of these new findings.