Temperature-guided radiofrequency cathether ablation of slow pathway in atrioventricular nodal reentrant tachycardia

Abstract

During the last several years, catheter ablation techniques with radiofrequency current have developed dramatically and have become the method of choice for curative therapy of atrioventricular (AV) nodal reentrant tachycardia. Initial reports have achieved AV nodal fast-pathway ablation with excellent results, but AV nodal slow-pathway ablation is currently the alternative to fast-pathway ablation because of an excellent success rate of 90 % to 100 % and the lower risk of AV block. 13 The ablative effect of radiofrequency energy is based on direct electric (resistive) heating and passive (conductive) heating of the tissue adjacent to the ablating electrode. 4 Assuming that only temperature is the basis for the ablative effects of radiofrequency energy, the temperature of the electrode-tissue interface is more reliable and a better predictor of radiofrequency lesion volume than other variables such as power output, duration of energy delivery, contact pressure of ablation electrode, size of electrode tip, and cavity blood flow. 57 Very few published studies were performed carefully to investigate the effects of temperature-guided radiofrequency catheter ablation on the treatment of AV nodal reentrant tachycardia. This investigation was performed to evaluate the efficacy and safety of temperature-guided radiofrequency catheter ablation of slow pathway for the treatment of AV nodal reentrant tachycardia. The study population consisted of 34 consecutive patients with symptomatic AV nodal reentrant tachycardia for 12 _+ 10 years (range 1 to 40 years). The 10 men and 24 women had a mean age of 44 _+ 16 years (range 14 to 72 years). Structural heart disease was present in four patients: mitral valve prolapse in 2, mitral stenosis in 1, and aortic valve regurgitation in 1. Electrophysiologic study and catheter ablation were performed with quadripolar