Cardiac resynchronization therapy (CRT) has been introduced as a treatment for selected heart failure patients, specifically those with symptomatic heart failure, left ventricular (LV) dysfunction, and intraventricular conduction delays. CRT is delivered by use of an implanted device and leads positioned in the right atrium, right ventricle, and left ventricle. In the early stages of CRT development, researchers affixed epicardial electrodes to the left ventricle by means of subxiphoid, thoracoscopic, or major surgical procedure. Currently there are a number of transvenous LV leads available that have undergone substantial evaluation. Reports indicate that such leads can be positioned safely by cannulating the coronary sinus and inserting the lead into the venous system. The leads are reported to have acceptable pacing/sensing thresholds and complication rates. Because of individual variations in the cardiac and venous anatomy, as well as sharp angulations in the venous system, maneuverability is an important consideration in lead selection.
Keywords: Key words Cardiac resynchronization therapy; biventricular pacing; heart failure; left ventricular lead.