PREDICTORS OF OUTCOME AFTER RADIOFREQUENCY CATHETER ABLATION OF THE ATRIOVENTRICULAR NODE FOR ATRIAL-FIBRILLATION AND CONGESTIVE-HEART-FAILURE

Background Although radiofrequency catheter ablation of the atrioventr icular (AV) node is an established treatment for atrial fibrillation ( AF) with uncontrolled ventricular response, factors that predict clini cal outcome in patients with associated congestive heart failure (CHF) are unknown. Methods and Results Av node ablation and permanent pacem aker implantation was performed in 44 consecutive patients (mean age 7 1 +/- 10 years) with CHF and AF associated with uncontrolled ventricul ar response. Immediately before ablation, mean left ventricular ejecti on fraction (EF) measured by 2-dimensional echocardiogram was 34.6% +/ - 9.8%, mean exercise tolerance time was 2.6 +/- 1.8 minutes, and mean quality of life score was 62.3 +/- 19.7 Complete AV block was achieve d in all 44 patients but was complicated by death in 1 patient from ca rdiogenic shock soon after ablation. By month after ablation, EF incre ased to 43.8% +/- 13.7% (P < .01), exercise tolerance time was 4.0 +/- 2.5 minutes (P < .01), and mean quality of life score decreased to 35 .6 +/- 18.1 (P < .01). Improved cardiac performance (increase in EF gr eater than or equal to 9% over baseline EF) was detected in 20 (45%) o f the patients. During a mean follow-up of 17 +/- 9 months, 5 patients died suddenly of presumed ventricular tachyarrhythmia and 4 others di ed of progressive CHF. Multivariate Cox survival analysis identified b aseline EF less than or equal to 30%, presence of significant mitral r egurgitation (>2+) before ablation, and failure to exhibit improved ca rdiac performance by 1 month after ablation as the only independent pr edictors of death. Conclusions Baseline variables and failure of EF to improve soon after AV node ablation identifies patients with CHF and AF who have a high mortality rate. Adjunctive therapy to reduce sudden death and progressive heart failure should be evaluated in this subgr oup.