This retrospective study reports the immediate and long-term results of percutaneous ablation of atrioventricular conduction. Between July 1983 and January 1992, 85 consecutive patients (51 men, age 64 +/- 10 years, range 43-84 years) presenting with supraventricular arrhythmias (atrial fibrillation n = 53; atrial flutter n = 50; atrial tachycardia n = 17; junctional tachycardia n = 6) resistant to antiarrhythmic therapy (number of drugs used: 4 +/- 1.3, range 1-6) underwent interruption of atrioventricular conduction by fulguration (n = 65) or radiofrequency energy (n = 13) or by an association of the two methods (n = 7). The 75 pacemakers implanted (10 patients had pacemakers before the procedure) comprised 55 VVIR, 11 VVI, 5 DDD and 4 DDDR units. The immediate results included two sudden deaths at the 4th and 7th day in patients undergoing fulguration and three complications with a favourable outcome (staphylococcal septicaemia, pulmonary embolism and haematoma at the site of implantation of the pacemaker). None of the patients was lost to follow-up and the average follow-up was 31 +/- 18 months (range 2-108 months). During follow-up, 15 patients died and there was a recurrence of symptoms in 11 patients after 1 to 9 months requiring a repeat procedure. In the 68 survivors, the follow-up is now 38 +/- 18 months (range 12-108 months). Sixty one patients have 2nd (2) or 3rd (59) degree atrioventricular block, giving 90% good electrocardiographic results.(ABSTRACT TRUNCATED AT 250 WORDS)