Atrioventricular nodal modification and atrioventricular junctional ablation for control of ventricular rate in atrial fibrillation.

Atrial fibrillation results in several structural and functional changes in the heart that lead to worsening ventricular function. Although restoration of sinus rhythm is the ideal goal, it is not always feasible. Pharmacologic therapy is associated with adverse effects and is not always effective. We have reviewed the current status of nonpharmacologic therapy in the management of rapid ventricular response due to atrial fibrillation. Electrophysiologic studies have confirmed that the posterior inputs to the AV node have a shorter refractory period and are mainly responsible for maintaining rapid ventricular response in atrial fibrillation. AV nodal modification involves ablation of these posterior inputs in a sequential fashion until a significant reduction of ventricular response is achieved. This procedure has been reported to be successful in maintaining the controlled ventricular response in about 70% of the patients over long-term follow-up. Ablation of the AV node with implantation of a permanent pacemaker is a more definitive procedure and simpler to perform. Reduction in ventricular response achieved with this procedure results in improvement of the patient's clinical symptoms as well as the underlying left ventricular function. Nonpharmacologic therapy for control of ventricular rate should be considered for patients with atrial fibrillation, in whom pharmacologic therapy for rate control is ineffective or poorly tolerated.