A method and apparatus for transmural ablation includes using an instrument comprising first and second jaws which each includes an ablation member. A clamping force is exerted on the two ablation members such that the tissue of the hollow organ is clamped therebetween. At least one of the first and second jaws further includes at least one EKG monitoring sensor on a tip of the associated jaw. The EKG sensor is spaced distally from its associated ablation member for contacting cardiac tissue. The EKG sensor is adapted to be connected to an EKG monitor, so that when cardiac tissue is grasped between the first and second grasping jaws, the EKG sensor contacts the cardiac tissue and transmits the signals generated by the tissue to the EKG monitor.