We developed a Teflon plunge electrode system (Telfon plunge) with important advantages over currently used electrodes. The Teflon plunge consists of an anchor-introducer (anchor) attached to the tip of an 0.8-mm diam epoxy-filled Teflon tube supporting six bipolar recording sites. The plunge is inserted through the myocardium into the ventricular cavity perpendicular to the epicardium. Once in the left ventricular cavity the anchor at the tip of the plunge pivots perpendicular to the long axis of the plunge and seats on the endocardium. It is maintained in position with a 4-0 nylon line (line) that extends from its attachment to the anchor through the body of the plunge to the epicardial end where it is secured with a Ligaclip. Thus the electrode contacts are placed a predetermined distance from the endocardium. When the Ligaclip is released, the plunge is removed from the heart leaving the line in the track of the electrode attached to the anchor as a marker for histological studies. The Teflon plunge will facilitate the evaluation of the role of the endocardium in ventricular arrhythmias by locating recording sites a stable, known distance from the endocardium and by marking the electrode track for histological studies.