Selective radiofrequency ablation of the "slow" atrioventricular nodal pathway for control of the ventricular response to atrial fibrillation.

In summary, this study reports 2 important findings: (1) AV nodal modification using the conservative protocol we describe reduces long-term success for ventricular rate control during atrial fibrillation but eliminates the incidence of permanent AV block; (2) directed lesions that eliminate clinical AV nodal reentry slow ventricular response to acute atrial fibrillation but are not sufficient to control ventricular response of chronic atrial fibrillation. Further refinement of these techniques may allow an optimal balance between rate control and avoidance of permanent pacing.