Methods and systems treat abnormal cardiac electrical activity employing a probe having first and second ablation electrodes disposed on a distal portion of the probe and a sensing electrode disposed between the first and second ablation electrodes, bringing the probe into contact with cardiac tissue, and applying energy through the first and second ablation electrodes to ablate target tissue along an ablation path, monitoring cardiac electrical activity using the sensing electrode to detect the cardiac electrical activity. After making an observation that the cardiac electrical activity is no longer detectable by the sensing electrode, energy application is terminated.