Implantable devices to treat atrial fibrillation: real prospects or just new gimmicks?

There are three potential roles to be played by implantable devices in patients with recurrent, drug-refractory and ill-tolerated episodes of atrial fibrillation (AF): (1) conventional antibradycardia pacing in AF patients with slow ventricular rate, either spontaneous or induced by AV-junctional ablation. The clinical efficacy of permanent cardiac pacing, whether in the VVIR mode in patients with chronic AF or in the DDDR mode in patients with paroxysmal AF, has now been clearly established. Pacing significantly improves symptoms and well-being and may improve left ventricular ejection fraction in tachycardia-induced cardiomyopathy. Early experience of AV-junctional ablation using high energy DC shock was reported to be associated with a potentially high risk of sudden cardiac death, which was later reduced by the introduction of new and less aggressive power sources. In reality, the main risk of this procedure is probably linked to pacemaker dependency, which occurs in approximately half of all patients; (2) atrial pacing to prevent AF recurrences; (3) antitachycardia pacing (ATP) and/or atrial cardioversion to stop automatically arrhythmia episodes. To date, the latter two therapeutic options have partially failed to meet expectations. The reasons for that include insufficiently validated clinical efficacy and poor tolerance of atrial cardioversion. Nevertheless, relentless technological and clinical research in this field should soon produce