Abstract 12542: Early Enrollment in Cardiac Rehabilitation Leads to Optimal Outcomes

Abstract

Background Cardiac rehabilitation (CR) benefits patients with coronary artery disease (CAD) and following cardiac surgery. Current guidelines state that early outpatient or (Phase 2) CR services are most beneficial when delivered 1 to 3 weeks after the index cardiac event. Enrollment in CR may be delayed following an index cardiac event, but the effect of delay time from index event to initiation of CR on outcomes is unclear.

Hypothesis We hypothesized that delay in enrollment would influence outcomes in patients undergoing CR. Methods 1,156 patients were enrolled in a structured 36-session program of CR for CAD or post-cardiac surgery. Risk factors and metabolic equivalent levels (METs) during moderate aerobic exercise were calculated before and after CR. Patients with missing index event dates were excluded (n=81). CR delay time was defined as the number of days between index hospitalization discharge and CR commencement.

Results The mean (±SD) CR delay time was 32.4 (±32.5) with a longest delay of 376 days. CR delay time >30 days was associated with older age, female gender, and non-white race compared to CR delay time ≤30 days (p30 days demonstrated significant improvements in all CR metrics. However, the magnitude of improvement was significantly decreased compared to CR delay times ≤30 days for all metrics except for systolic/diastolic pressure (see table). After multivariable adjustment, delay time well beyond 30 days remained an independent predictor of decreased MET improvement compared to a delay time <30 days (r = -0.24, p<0.001).

Conclusion Participation in CR is of greatest benefit, particularly on weight and exercise capacity, when initiated as soon as possible after an index cardiac event. Nonetheless, improvement continues to be seen in exercise capacity, body weight, and risk factors in patients who delay enrollment even well beyond 30 days.