[Permanent atrial fibrillation and heart failure: radiofrequency ablation of atrioventricular junction and cardiac resynchronization therapy: review of the literature and of the new techniques for echocardiographic assessment].

Radiofrequency ablation of atrioventricular junction plus pacing therapy ("ablate and pace") is an effective non-pharmacological therapy in patients with medically refractory permanent atrial fibrillation and heart failure. However, the chronic right ventricular pacing may result in regional wall motion abnormalities and adverse hemodynamic effects. These findings imply that patients with permanent atrial fibrillation who undergo "ablate and pace" may benefit from cardiac resynchronization therapy. The review of both observational and randomized studies suggests an important role of biventricular pacing combined with atrioventricular junction ablation only in patients with severe reduction of left ventricular ejection fraction and advanced heart failure. In all other patients with permanent atrial fibrillation, the comparison of conventional right ventricular pacing with respect to cardiac resynchronization therapy showed conflicting results. The assessment of cardiac dyssynchrony by means of new echocardiographic technology, including three-dimensional analysis, may improve the selection of the best pacing modality in patients undergoing "ablate and pace" for drug refractory permanent atrial fibrillation.