RADIOFREQUENCY CURRENT ABLATION OF SUPRAV ENTRICULAR TACHYCARDIAS IN CONGENITAL HEART-DISEASE

Supraventricular tachycardia is a frequent cause of disease in patient s with congenital heart defects and has a potentially high impact on q uality of life, morbidity and mortality of this patient cohort. Conven tional treatment often fails to avoid recurrences of tachycardia in a long-term perspective. Potential side effects of antiarrhythmic drugs include aggravation of heart disease related disturbances of impulse g eneration and conduction properties or negative inotropic effects on h aemodynamically impaired ventricular chambers. For these reasons, inte rventional electrophysiology is increasingly used for the treatment of supraventricular tachycardias in patients with congenital heart disea se. Until March 1998 a total of 83 patients with congenital heart defe cts underwent an attempt for radiofrequency current treatment of supra ventricular tachycardias. Among these were 36 children with an age of 5 months to 15 years (8.2 +/- 4.6 years) and 47 grown ups with an age of 17 to 76 years (39.3 +/- 14.3 years). In a natural course or preope rative status of the congenital heart disease were 35 patients, while palliative or corrective surgery was performed in 48 patients. Suprave ntricular tachycardia was based on a total of 63 congenital arrhythmog enic substrates, among them were 53 accessory pathways, 4 Mahaim fibre s, 5 functionally dissociated AV-nodes and an anatomically doubled spe cific conduction system including 2 distinct AV-nodes in one case. In the remaining patients with tachycardia based on acquired arrhythmogen ic substrates there were 45 incisional atrial reentrant tachycardias, 15 atrial flutters of the common type and 6 ectopic atrial tachycardia s. In a total of 105 sessions 78 of the 83 patients were successfully treated with the use of radiofrequency current ablation. There were no significant procedure related complications. Radiofrequency current a blation can be carried out safely and successfully for the treatment o f supraventricular tachycardia in young and adult patients with congen ital heart disease. As such therapeutic strategy meets the specific re quirements of this patient cohort, early consideration for this therap y is recommended.