Noncontact mapping-guided catheter ablation of atrial fibrillation associated with left atrial ectopy

Noncontact Mapping of Atrial Fibrillation. We report the use of a novel non contact mapping system used to perform left atrial mapping and to guide rad iofrequency ablation in two patients, each with atrial fibrillation (AF) tr iggered by left atrial ectopy. A noncontact multielectrode probe and ablati on catheter were advanced into the left atrium through a transseptal punctu re or a patent foramen ovale. Isopotential mapping delineated the focal ori gin at the ostium of the right lower pulmonary vein in one patient and clos e to the ostium of the left upper pulmonary vein in the other patient. The ablation catheter was guided to the target sites using a locator signal. Th e foci mere ablated successfully in both patients. No recurrences of AF wer e observed during follow-up at 4 and 6 months, respectively.