The authors analysed the clinical and paraclinical variables of 116 patients admitted to the Hôpital Cardiologique de Lyon between 1986 and 1990 with sustained ventricular tachycardia without cardiocirculatory arrest in order to determine the long-term outcome and the prognostic factors of death and recurrence. The average age of the patients was 56 +/- 15 years (mean +/- SD) and 83% were men. The mean ejection fraction was 39 +/- 15%. Sixty-five had previous myocardial infarction (group I); 30 (group II) had dilated cardiomyopathy (n = 21), right ventricular dysplasia (n = 4), hypertrophic cardiomyopathy (n = 2), congenital (n = 2) or valvular (n = 1) heart disease. Group III comprised 21 patients with no apparent cardiac disease or isolated mitral valve prolapse. Brief syncope was reported in 12 cases. The paraclinical investigations showed 46 patients (66%) with at least two criteria of positivity for ventricular late potentials; Holter recording showed doublets or runs of VES in 46% of cases and sustained or non-sustained VT was induced during exercise testing in 16 patients (22%). Programmed ventricular stimulation triggered VT in 85%, 79% and 61% of patients in groups I, II and III respectively. The patients were treated with amiodarone in 65 cases, a betablocker in 25 cases, catheter ablation of the origin of the tachycardia in 12 cases, antiarrhythmic surgery in 6 cases, coronary bypass grafting in 5 cases (with an associated antiarrhythmic procedure in 3 cases). An automatic defibrillator was implanted in 9 patients. The average follow-up period was 32 months (range: 17 days to 65 months).(ABSTRACT TRUNCATED AT 250 WORDS)