Response to Cardiac Resynchronization with Epicardial versus Transvenous Left Ventricular Leads Assessed by Echocardiography in Time Frame of 5 Years

Objectives: Cardiac resynchronization therapy (CRT) is an inherent part of therapeutic portfolio of advanced heart failure. Resynchronizing of ventricular dyssynchrony may improve the impaired ventricular pump function. Additionally, reverse ventricular remodeling may occur. Unfortunately, up to 20% to 30% of patients do not respond to CRT. A non-optimal left ventricular (LV) lead position may be a potential cause for nonresponse to CRT. As optimal placing of transvenous LV (tLV) leads is dependent on suitable venous anatomy, surgical placement of epicardial LV (eLV) leads usually allows optimal lead positioning. Besides clinical symptomatology, echocardiographic (EG) evaluations provide the most important indicators of CRT success. Methods: Patients with implanted CRT were yearly investigated for clinical symptomatology and EG parameters of ventricular remodeling in a time frame of 5 years. All data were retrospectively analyzed from internal institutional database. Results: 696 patients underwent tLV and 133 eLV implantation. The preoperative characteristics were comparable in both groups. Preoperative ejection fraction (EF) was 24.6 in tLV and 27.9% in eLV group (n.s.). Within 5 years post-implantation the EF remained stable and only marginal changes in both groups were documented. The end-systolic LV diameters were preoperatively 57 in tLV and 54mm in eLV group. The initial reduction was followed by plateau with only small variations during the follow-up. The end-diastolic LV diameters (preoperatively 66 in tLV versus 64mm in eLV group) remained almost unchanged. The NYHA class analysis showed a significant initial drop followed by symptomatic stability thereafter. Conclusions: The long-term observation of EG parameters after CRT implantation confirmed the expected benefit of CRT therapy. This was emphasized by the reduced symptomatology of patients as showed by improvement in NYHA class. No significant differences concerning tLV versus eLV could be demasked.