[Intracorporeal cardiac pacemakers for refractory tachycardia (excluding atrial disease). Apropos of 18 cases].

The treatment of paroxysmal tachycardia by the use of permanent pacing to prevent or terminate attacks is discussed. The series comprises 18 patients with follow-up periods ranging from 1 to 12 years. In 6 cases the indication for pacing was atrial tachy-arrythmias favourised by bradycardia (5 of whom had vagally- induced atrial arrythmias). The atrial pacemaker successfully prevented attacks in 4 out of 6 cases. Three cases of chronic reciprocating tachycardia were successfully treated by simultaneous atrial and ventricular pacing or using sequential pacing with a very short P-R interval. Eight cases of paroxysmal orthodromic reciprocating tachycardia in the WPW syndrome were paced: in 5 cases pacing was employed to terminate attacks by atrial (3 cases) or ventricular (2 cases) stimulation, in the other 3 cases pacing was used to prevent the bradycardia which favourised the initiation of tachycardia. Good results were obtained in all 8 cases. Ventricular stimulation was used to terminate attacks in one patient with refractory ventricular tachycardia but the patient had a sudden death probably caused by the pacemaker. The place of these different pacing techniques with respect to medical treatment and specialised arrhythmia surgery is discussed.