Cardiac rehabilitation (CR) program has been established as an effective and essential treatment modality for management and secondary prevention of various cardiovascular diseases, and strongly recommended in many guidelines. Among them, evidence for the effect of exercise-based CR was most abundant in coronary artery diseases. However, there is still a significant gap between the recommendations in guidelines and real-world practice due to various hurdles in implementation. Moreover, recently there is a concern whether the effect of CR is still significant with optimal medical treatments and wide application of PCI. It has been argued that major advances in medical management of coronary artery disease may have led to a reduction in the incremental effect on mortality of exercise-based CR compared with usual care alone. Other concerns have included the inclusion of small, poor-quality RCTs, which may have resulted in overestimation of the benefits of CR, and the almost exclusive recruitment of low-risk, middle-aged, post-myocardial infarction (MI) men in early trials, thereby reducing the generalizability of their findings to the broader population of coronary patients.
Recently updated meta-analyses mostly showed that exercise-based CR reduces cardiovascular mortality, reductions in hospital admissions and improvements in quality of life. However, all the meta-analyses do not show the same results and there are studies with different conclusion that CR is not clearly associated with improved outcomes. Such results are probably associated with patient groups with lower risk and optimal treatment and also there is a possibility that irregular and/or poor adherence to CR has some role in the dilution of its effect in trials. Overall, it would be fair to say that while it is difficult to deny the effect of CR entirely, there are certainly a trend of decreasing outcome benefit.
On the other hand, modern CR program is aiming at comprehensive program including patient education and behavioral modification and not just exercise training. Long-term behavioral modification is an important aspect of patient management which cannot be replaced by pharmacological and/or procedural treatment, while proving its effect in trials is much more difficult compared to other pharmacological or procedural treatments.
In conclusion, CR is still an important and essential component in the management of cardiovascular diseases and various efforts should be exercised to improve the performance of CR and patient’s adherence to maintain its effect in the era of statins and PCI’s.