Significant residual coronary obstruction: impact on short and long-term outcomes of a cardiac rehabilitation program in coronary heart disease

Abstract

Introduction: There is evidence that cardiac rehabilitation programs (CRP) exert significant benefits in patients with coronary artery disease (CAD). However, safety and influence of residual significant coronary stenosis on CRP outcomes remain unclear. Methods: We retrospectively analyzed clinical, angiographic and functional data of a total of 287 patients referenced to a CRP after an acute coronary syndrome (ACS), between September 2008 and December 2011. Incomplete revascularization (IR) was defined by the presence of residual structural stenosis in any major epicardial vessels (>70%), consequent to unfavorable anatomy to angioplasty (PCI). Pre and post CRP functional capacity was assessed using exercise stress testing metabolic equivalents (METS). A composite outcome of overall mortality and nonfatal cardiovascular events was evaluated. Furthermore, functional capacity at follow-up evaluation was estimated using the patient-reported Duke Activity Status Index (DASI). Results: We analyzed 280 patients, mostly male (88%), aged 54±10 years. Incomplete revascularization (IR) was found in 61 (23%) patients. IR patients more frequently presented previous diagnosis of coronary heart disease (CHD) (25% vs 12%, p=0.009). They and also tended to be more often women (36% vs 22%, p=0.082) and diabetic (21% vs 14%, p=0.155), although these differences were not statistically significant. Physical training in pts with IR was safe and well tolerated. Exercise capacity increased significantly in both groups (peak MET level: + 0.7±1.7, p=0.013, in IR vs 1,0±1.7, p 0.05). The mean follow-up time was 30±13 months. Both groups showed a similar perceived physical performance, using DASI estimated peak METs (8.0±1.6 [IR] vs 8.3±1.6 [CR], p>0.05). Composite endpoints were found in 36 (10%) patients and occurred more in IR patients (19% vs 13%); however, the difference was not statistically significant (p>0.05). Kaplan Meyer showed no difference in the likelihood of a cardiovascular event, between IR and CR patients (p>0.05). Conclusion: IR patients take similar advantage from a CRP and maintain an equivalent long-term functional capacity. Although signficant residual stenosis is frequently regarded as a relative exclusion criteria for cardiac rehabilitation, these patients derive similar benefits both in short and long-term functional capacity, cardiovascular morbidity and mortality.