Experiences with a new transvenous electrode for left ventricular stimulation

Abstract

Left ventricular and biventricular pacing has recently been introduced as a new therapy for chronic heart failure in selected patients. We report our initial experience with a new electrode for transvenous left epicardial pacing via tributaries of the coronary sinus. Inclusion criteria were: chronic heart failure NYHA > or = II, QRS-duration > 120 ms, left ventricular ejection fraction < 35%. Dual chamber pacemakers (CPI Contak TR) or defibrillators (CPI Contak CD) designed for atrial triggered biventricular stimulation were implanted in conjunction with the CPI Easytrak-lead for left ventricular pacing in a coronary vein. Lead placement was achieved via a subclavian vein access and a preformed guiding catheter for coronary sinus insertion. In 13 of 16 patients (81%) the left ventricular lead was implanted successfully in a mid to distal posterior or anterolateral vein. Lead insertion could not be achieved in 2 patients with significant cardiomegaly and right atrial enlargement (12.5%), while 1 patient with a history of myocardial infarction and small anterior ventricular aneurysm had inacceptable high left ventricular pacing thresholds intraoperatively. The implantation was well tolerated by all patients without complications. There was no case of lead dysfunction (mean follow-up time: 142 +/- 126 days). Intraoperative electrode measurements and chronic parameters (> or = 3 months, n = 8) are given in Table 1. In the past left ventricular pacing has mainly been achieved by epicardially placed electrodes after thoracotomy with conventional electrodes. This new approach for chronic left ventricular pacing uses the familiar transvenous over-the-wire technique in combination with a newly developed guiding catheter and electrode for pacing in left epicardial veins. Lead placement was shown to be safe and success rate was higher than in previous reports with standard electrodes. We conclude that left epicardial lead placement with the over-the-wire technique and a preformed guiding catheter for coronary sinus access presents as a safe and maybe more efficient method for left ventricular pacing.