Evaluation of the American Association of Cardiovascular and Pulmonary Rehabilitation Exercise Risk Stratification Classification Tool without Exercise Testing

Purpose: The American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR) recommends that patients starting cardiac rehabilitation (CR) undergo stratification to identify risk for exercise-related adverse events (AE), but this tool has not been recently evaluated. Methods: Among patients who enrolled in CR in 2016, we used the AACVPR risk stratification tool to evaluate the risk for AE and clinical events (CE). We defined AE as signs or symptoms that precluded or interrupted exercise during CR, and CE as events requiring an urgent evaluation outside of CR exercise sessions. Results: During the study period, 657 patients with cardiovascular diagnoses were included and classified as high (58%), medium (31%), or low risk (11%). Over the course of CR (76 d, 17 sessions), there were 63 AE and 33 CE. Adverse events were mostly minor (no cardiac arrests or deaths) and managed by CR staff members. When compared with the low- or medium-risk groups, the high-risk group was more likely to have AE (HR 3.0 [95% CI, 1.7-5.9], P =.002) and CE (HR 3.7 [95% CI, 1.5-10.8], P =.002) with fair model discrimination (area under the curve: 0.637, P <.001). Conclusion: The AACVPR risk stratification tool was predictive of both AE and CE with fair discrimination, although event rates were low and mostly minor. Thus, the AACVPR model may require reevaluation to better identify truly at-risk patients for major AE.