Risk factor stratification of sudden death in idiopathic cardiomyopathy

In 178 patients with idopathic cardiomyopathy, the risk factor stratifications of sudden death (SD) were analysed. Among them, 19 cases died suddenly. 55.2% (16/29) of patients with SD had a history of recurrent sustained ventricular tachycardia (S-VT). The incidence of SD in the patients with recurrent non-sustained ventricular tachycardia (nonS-VT) was 5.36% (3/56). Programmed electrical stimulation (PES) was performed in 39 patients with ventricular tachyarrhythmias (VT), 19 patients had inducible S-VT, SD occurred in 10 patients (52.6%). S-VTs were not induced in 20 patients, SD occurred in only 2 patients (10%). Signal-averaged ECG (SAECG) was studied in 33 patients with VT. The late potenitials (LPs) were demonstrated in 15 cases, in which 8 cases suffered SD (53.3%). The SAECG was normal in 18 cases, SD occurred in only 3 cases (16.6%). The right ventricular out-flow tract studied by echocardiogram was greater in SD group than in non-SD group. This study has demonstrated that S-VT occurred spontaneouly or induced by PES, positive LPs and RV dilation may predict the risk to arrhythmogenic SD in patients with idiopathic cardiomyopathy.