Safety of exercise training for cardiac patients : results of a French multicenter COCARE study (COmplications in CArdiac REhabilitation)

Abstract

Background

Cardiac rehabilitation is widely recognized as beneficial for patients with coronary artery disease, post-cardiac surgery, and heart failure, although it is underutilized. However, the benefit-risk balance must be updated to reflect the evolving characteristics of treated populations.

Objective

To evaluate the safety of supervised exercise training in a large sample of French cardiac rehabilitation patients, and to assess the utility of the modified Risk of Activity Related Events (RARE) score in identifying low-risk individuals.

Methods

This multicenter observational study included 6,793 patients from 32 centers surveyed between 2023 and 2025. Each center collected data over four consecutive months, including patient characteristics and events that interrupted programs, required transfer to acute care, or resulted in rehabilitation cessation. The modified RARE score was applied to identify a low-risk subgroup. Events were considered activity-related if they occurred during or within one hour of a training session.

Results

A total of 964 events (14.2%) were reported, of which 154 (2.3%) were activity-related. Two cardiac arrests occurred—one fatal—representing 0.98 cardiac arrests and 0.49 deaths per 100,000 patient-hours of training. A modified RARE score < 4 defined a low-risk group with an area under the ROC curve of 0.67 and an excellent negative predictive value (0.99). However, specificity was limited (0.32), reflecting the low incidence of events even in high-risk patients.

Conclusion

The COCARE study confirms the low risk of supervised exercise in phase II cardiac rehabilitation. The modified RARE score may be useful in identifying patients who could safely benefit from alternative, less monitored formats such as telerehabilitation.