A hybrid approach to cardiac resynchronization therapy

Abstract

Background: CRT (atrial-synchronized bi-ventricular pacing) has been shown to significantly improve the quality of life and exercise tolerance in patients with moderate-severe heart failure and an interventricular conduction delay (>120 msec) when compared to controls. Traditionally it has been performed by cardiologists in electrophysiology laboratories. In the event that the left ventricular lead cannot be positioned percutaneously the procedure is aborted and the cardiac surgeon consulted. The subsequent intervention by the surgeon, typically on another day, requires reexploration of the pocket, a thoracotomy, which results in an increase in length of stay (LOS), and an increase in infection risk. The objective of this study was to demonstrate that CRT could routinely be performed in a surgical operating room (OR) as a single rather than a staged procedure.

Methods: Between 1/1/06 and 7/1/06 18 patients (17 male and 1 female) with an average age of 56 years (range 36-79) underwent CRT. Transthoracic echo (TTE) revealed that all had left ventricular ejection fractions (LVEF) <30% (range 8%-28%). Five of the 18 had moderate-severe mitral regurgitation (MR). The etiology of the cardiomyopathies was ischemia in 4 and non-ischemia in 14. All had QRS intervals >120 msec (range 120-200 msec) and all were maintained preoperatively on their conventional therapy for heart failure (B-blockers, ± diuretic, ± ACE-I or ARB) and all were either New York Heart Association (NYHA) functional class III or IV. Every case was performed under general anesthesia with an arterial line and Foley catheter in the semi right lateral decubitous position. Nine of the 18 patients underwent a left anterolateral mini-thoracotomy for epicardial left ventricular (LV) lead placement. All hardware included defibrillation technology (ICD).

Results: All 18 patients left the OR with successful bi-ventricular pacing in an average time of 170 minutes (range 140-200 min). The average epicardial lead pacing threshold was 0.9v (range 0.4-1.5v) while the average endocardial (transvenous) threshold was 0.4v (range 0.2-0.7v) at a pulse width of 0.5 msec. TTE at 1 month demonstrated an improvement in LVEF in 14/18 patients with an average increase of 5% (range 2%-9%). Four of the 5 patients with moderate-severe MR were reduced to mild. The average length of stay (LOS) following the procedure, in those patients who did not undergo a thoracotomy, was 4 days (range 3-6 days) while it was 7 days (range 6-10 days) in those who underwent a thoracotomy.

Conclusion: These data clearly indicate that CRT can be successfully performed as a single-staged procedure in a cardiac OR. Although transvenous LV lead placement avoids a thoracotomy, the epicardial LV lead thresholds, in this series, are competitive with the transvenous results. We propose that in the spirit of cost containment, fee bundling, decreasing reimbursement, pay-for-performance, and infection control, these complex interventions should be performed in multipurpose interdisciplinary hybrid cardiac OR's, now available in most major medical centers, with designated time limitations and role assignments.