New developments and treatment strategies in patients with supraventricular tachyarrhythmias.

The mechanisms, clinical presentation and therapy of supraventricular tachycardias are discussed. The therapy has changed from palliation by means of anti-arrhythmic drugs into definitive cure by ablation of the arrhythmia substrate. Radiofrequency energy causes tissue damage by heating and appears to be a safe method for catheter ablation of supraventricular tachycardias. We report a 97% success rate for radiofrequency ablation of 195 accessory atrioventricular pathways thereby curing these patients from circus-movement tachycardia and paroxysmal atrial fibrillation. Complications occurred in 3% of patients. One hundred seventy-two patients with atrioventricular nodal reentrant tachycardia, caused by reentry within dual AV-nodal pathways, were treated by selectively ablating one of the pathways with non-inducibility of the arrhythmia afterwards in 97% of the cases. Nine percent of patients had a recurrence but were successfully treated in a second session. The procedure was complicated by complete AV-block in 4% of patients. The disappointing medical treatment of atrial fibrillation and the fact that atrial fibrillation can be the cause of a reversible form of heart failure (tachycardiomyopathy), induced the clinical application of alternative forms of treatment. Ablation of the normal atrioventricular conduction system by using radiofrequency energy was performed with a 100% success rate in 121 patients. After implantation of a ventricular pacemaker it is possible to control and regulate the ventricular rhythm leading to rate control and amelioration of ventricular performance.