Device Implantation in High Risk Patients after Cardiac Surgery – Is Early ICD or CRT Implant Justified?

Abstract

Introduction: Patients undergoing cardiac surgery often have both acute and chronic depression of left ventricular function. If the operative intervention results in the need for bradycardia support and heart failure is present after surgery, the decision regarding the type of device is influenced by whether there is an expectation for significant improvement in ventricular function. In many cases, this is unknown. Methods: Data was collected prospectively from a longitudinal cohort of consecutive patients undergoing CABG and/or valvular surgery at USC from 2003 to 2006. In this interval, post-operative patients with bradycardia, depressed ventricular function, and heart failure were evaluated jointly by the EP and Cardiothoracic service and treated with primary prevention ICD or CRT defibrillator prior to discharge. Registry data was analyzed to assess the clinical outcomes. Results: Twenty-three patients (mean age 67.5 years, 69% male) were considered eligible for implant. One third required pre-operative support with an IABP and 26% of patients underwent both CABG and valve surgery. The pre-op mean LVEF was 24.5% and increased to 31.7% over a mean follow-up of 12.4 months. At one year, both ICD and CRT patients experienced improvement in LVEF (p = .04 and p = .02, figure) and the mortality rate was 17%. Two patients received appropriate ICD shocks. There was one late device complication requiring explant for infection. Conclusions: This registry data indicates that the impact of primary prevention ICD or CRT placement prior to hospital discharge after cardiac surgery on outcomes is favorable in high-risk patients with bradycardia indications and/or heart failure in association with low LVEF. ICD therapies are utilized. The improvement in LVEF is modes and similar with ICD and CRT devices. The cardiac surgical procedure itself, may account for the improvement in cardiac function.