Abstract 14449: Estimated Life-time Risk to Ages 80: Impact of Out-Patient Cardiac Rehabilitation in Patient with Low Prognostic Risk after Acute Myocardial Infarction

Abstract

Object: The purpose of this study was to assess whether participation in out-patient cardiac rehabilitation (OPCR) program reduces life-time risk for cardiovascular disease to ages 80 after acute myocardial infarction (AMI).

Background: Life-time risk for cardiovascular disease has been reported to be associated with both the coronary risk burden and physical fitness level. However, it is unknown whether participation in OPCR program reduces Life-time risk in patients after AMI independent of short-term prognostic risk.

Methods and Results: We assessed “estimated Life-time risk to ages 80” (eLTR80) in 835 consecutive AMI patients who participated in OPCR and underwent cardiopulmonary exercise test. eLTR80 was calculated in each patient according to Berry et al (JACC 2011;57:1604-10), incorporating age, coronary risk burden, and cardio-respiratory fitness at the beginning and the end of the 3-month OPCR. Patients were divided into two groups: active OPCR participants (n=118; ≥25 sessions/3 months) and non-active participants (n=308; <10 sessions/3 months). At baseline, there was no significant difference in age (Active 65 vs Non-active 62years, NS), left ventricular ejection fraction (45 vs 45%, NS), peak oxygen uptake (PVO2 1316 vs 1338 ml/min, NS), or eLTR80 (11.1% vs 11.5%, NS). Compared with non-active participants, active OPCR participants showed a significantly greater improvement in PVO2 (12.8% vs 8.8%, P<0.01) and a greater percent decrease in eLTR80 (15.9% vs 5.4%, P<0.05) at the end of the 3-month OPCR program. When the analysis was limited to 144 patients supposed to have low short-term prognostic risk (age<65 years, successful reperfusion, Killip class I, peak creatine kinase<6,000U/L, and left ventricular ejection fraction≧40%), the magnitude of reduction of eLTR80 was even greater in active OPCR participants than in non-active participants (28.2% vs 12.5%, P<0.05).

Conclusions: Active participation in OPCR after AMI is associated with a significantly greater reduction of “estimated lifetime risk to ages 80”. This finding may hold true even in AMI patients with low prognostic risk.