A Percutaneous Coronary Intervention (PCI) guidewire and method of use includes at least two pairs of small surface area, closely spaced electrodes spaced axially along the length of the guidewire to allow one electrode pair to be positioned on each side of a coronary stenosis. The electrodes can sense electrical signals from the myocardium immediately adjacent to the electrodes, enabling the guidewire to record and analyze an Intra-Coronary Electrogram (ICEG) and heart pacing, and, therefore, facilitate more accurately diagnosis of an individual patient's stenosis and provide a more patient specific diagnosis of clinical need.