Cardiac rehabilitation is associated with reduced long-term mortality in patients undergoing combined heart valve and CABG surgery

Background: No reports have been published to date on the impact of cardiac rehabilitation (CR) on mortality in patients undergoing combined heart valve and coronary artery bypass graft (CABG) surgery (V+CABG), a procedure that has increased significantly in frequency in recent years. Methods: We identified consecutive patients who underwent V+CABG surgery in the Olmsted County from 1996 to 2007. Propensity scores were developed using more than 40 clinical, operative, and post-operative characteristics. The impact of CR on long-term mortality was assessed via landmark analysis and using propensity score regression adjustment and stratification techniques. Results: A total of 201 patients were included in our study, in whom 86 deaths occurred over a mean follow up of 6.8 years. Forty-seven per cent of patients participated in CR, with a significant trend towards increased participation in recent years (p=0.04). Conditional on 6-month survival and controlling for propensity factors as well as mortality risk factors, CR participation was associated with a significant reduction in mortality (propensity score adjustment: HR 0.48, p=0.009; propensity score stratification: HR 0.48, p=0.016). The absolute risk reduction over 10 years was 14.5% (number needed to treat=7). Results did not differ significantly based on age, gender, emergent status, or history of heart failure or arrhythmias, but CR participation was more beneficial for patients who underwent a mitral valve procedure (HR 0.24, 95% CI 0.08-0.77). Conclusions: This is the first study reporting a significant survival benefit with CR participation in patients who have undergone combined V+CABG surgery. These findings provide evidence in support of recommendations for CR participation after V+CABG surgery.