Background: The safety of exercise-based cardiac rehabilitation (CR) has not been investigated in Japan, so a nationwide survey was conducted to investigate the incidence of adverse events (AEs) associated with CR and exercise testing.
Methods and results: In total, 136 hospitals reported operating recovery-phase CR programs, amounting to 383,096 patient-hours of exercise training. The incidence rates of all AEs and life-threatening AEs (LAE: death, cardiac arrest, acute myocardial infarction, cardiac rupture) during exercise sessions were 12 and 1 event/383,096 patient-hours (3.13 and 0.26 events/100,000patient-hours), respectively. When CR programs were categorized as "Formal" in which an exercise prescription based on exercise testing was issued to individual patients or "Non-formal" without exercise prescription, the incidence of AEs during and within the 24 h after an exercise session was significantly lower in the Formal than the Non-formal CR programs (P<0.001), despite similar hospital size and coronary intervention volumes between the 2 category hospitals. Moreover, LAEs did not occur in 277,721 patient-hours in Formal CR, whereas 2 LAEs occurred in 105,375 patient-hours in Non-formal CR (P<0.05). During 469,215 exercise testing sessions, 3 LAEs (0.64 event/100,000tests) and 31 non-LAEs (6.61 events/100,000tests) occurred.
Conclusions: This first nationwide survey in Japan revealed that both exercise-based CR and exercise testing are generally safe, and that Formal CR, in which an individual exercise prescription is determined by exercise testing, is particularly safe.