Efficacy and safety of septal and left-atrial linear ablation for atrial fibrillation

Atrial fibrillation (AF), the most common of all sustained cardiac arrhythm ias, is frequently resistant to antiarrhythmic drugs, and physicians have s een limited success with catheter ablation limited to the right atrium. As a result, the safety and efficacy of systematic biatrial linear ablation fo r drug resistant AF was investigated. Forty-four patients (54 +/- 7 years) underwent catheter ablation of daily drug-resistant AF. Two right-atrial li nes (1 septal and 1 cavotricuspid) and 3-4 left-atrial lines were transsept ally performed: 2 joining each superior pulmonary vein to the posterior mit ral annulus and 1 interconnecting them. An additional left-atrial septal li ne from the right superior pulmonary vein (RSPV) to the foramen ovalis was performed in 23 patients. Radiofrequency was delivered with a conventional thermocouple-equipped ablation catheter or with an irrigated tip ablation c atheter for resistant cases and for sparing the endocardium. Of the 44 pati ents, 25 (57%) were successfully treated without antiarrhythmic drugs. Twel ve patients (27%) improved (<6 hours of AF per trimester under a previously ineffective drug) and 7 (16%) were considered treatment failures. Multiple sessions were required to ablate new left-atrial macro-reentry and initiat ing foci (2.7 +/- 1.3 procedures per patient). Five patients had a pericard ial effusion and 1 each a pulmonary embolism, an inferior myocardial infarc tion, and a reversible cerebral ischemic event. One patient had thrombosis of the 2 left pulmonary veins. Despite a relatively high success rate, this procedure is too long, and the safety and efficacy need to be improved and applied to a broader range of patients. (C)1999 by Excerpta Medica, Inc.