Cardiac rehabilitation: improving the prognosis of ischemic heart disease

Abstract

Introduction: Cardiac Rehabilitation (CR) aims to help patients overcome the limitations experienced after a significant cardiac event. Even though its benefits are well established, CR is still underused. Moreover, the evidence that CR can bring benefits on hard endpoints in real-world patients is extremely important in an era of strict control of costs. Our goal was to determine the success of CR in the global performance of our patients, to explore the effect of CR on validated surrogate markers of prognosis and attempt to evaluate the long-term benefits of CR. Methods: We studied all the patients referred to a hospital-based multidisciplinary Cardiac Rehabilitation Program after acute coronary syndrome or elective percutaneous coronary intervention. All patients completed 2 to 3 months of biweekly supervised aerobic exercise of moderate intensity. They underwent exercise stress testing at the beginning of the Program (EST1) and after 3 months (EST2). We tested the maximal exercise capacity, proBNP, maximal heart rate and Duke treadmill score as potential prognostic markers. The endpoint was the occurrence of major adverse cardiac composite events (MACCE): cardiac death, urgent revascularization and hospitalization from cardiac causes. Level of statistical significance p<0,05. Results: A total of 723 consecutive patients that attended the Program were included, the mean age was 60 years old and 75% were male. The median follow-up time was 25 months. After completion of the CR, there was a significant improvement in functional capacity (8.8±3.8 METs at EST1 vs 10.1±2.3 METs at EST2; p<0.001). The Duke score decreased significantly (6,8±4,9 at EST1 vs 7,9±5,2 at EST2; p<0,001) and the maximal heart rate during exercise increased (from 130 bpm ±20 to 134 bpm ±20; p<0.001), a manifestation of chronotropic competence. The proBNP decreased from 751±930 pg/mL to 366±442 pg/mL; p<0.001. We verified that each one of these 4 markers, when evaluated after completion of the CR program, was a predictor of MACCE, even after adjustment for multiple characteristics such as age, gender, comorbidities and left ventricular systolic function. Conclusions: We observed a tremendous beneficial effect of CR on prognostic markers in our large sample of real-life patients with coronary disease, highlighting its role in secondary prevention. This benefit translated into MACCE even after 2 years and was seen in all groups of patients. We also verified that the maximal exercise capacity, Duke treadmill score, proBNP and maximal heart rate could be used as markers of success of a CR program.