MRI in cardiac electrophysiology: the emerging role of delayed-enhancement MRI in atrial fibrillation ablation.

Catheter ablation of atrial fibrillation has emerged as a viable therapeutic option for those patients who have failed conventional medical therapy. This treatment strategy has been introduced in the past decade following the discovery of ectopic foci in the pulmonary veins capable of initiating this arrhythmia. The basis of current ablation techniques relies on inducing myocardial necrosis at distinct anatomical landmarks in order to electrically isolate these ectopic foci and to disrupt pulmonary vein and left atrial conduction pathways. The recent introduction of a delayed-enhancement cardiac MRI sequence now allows for the noninvasive assessment of the location and extent of left atrial scarring following the ablation procedure. In this review, we describe this novel scan sequence and its current and potential role in catheter ablation of atrial fibrillation.