A method of ablating an epicardial tissue region, including positioning a medical device adjacent the epicardial tissue region, the medical device having a first electrode, a second electrode, and a third electrode located in between the first and second electrodes delivering an irrigation fluid to the tissue region and ablating at least a portion of the tissue region by sequentially activating the third electrode in a monopolar radiofrequency delivery mode and activating the first and second electrodes in a bipolar radiofrequency delivery mode.
