Stable improvement of older outpatients with acute coronary syndrome after one year of exercise-based secondary prevention program. Insights from the ITER registry

Purpose: Among cardiovascular diseases, acute coronary syndrome (ACS) is the leading cause of morbidity and mortality. Cardiac rehabilitation and secondary prevention programs are highly recommended for the long-term management of patients, and physical activity has been recognized as core part of such interventions. However, despite the documented benefits, older patients diagnosed with acute coronary syndrome (ACS) are less likely to attend traditional center-based programs limiting the efficacy of the intervention. Therefore, more comprehensive and sustainable intervention strategies are advocated. In light of these considerations, the aim of the study was to examine functional changes of older patients with ACS involved in a hybrid center- and home-based secondary prevention program during the first year of intervention after the acute event. Methods: A subsample of 254 consecutive patients (mean age 75 years) with ACS extracted from the ITER registry (NCT05817305) was analyzed. The intervention was composed of 6 individual on-site sessions including functional evaluation and continuous motivational reinforcement to reach exercise goals and stably maintain an active lifestyle. The home-based exercise prescription was based on the results of the validated 1km-Treadmill Walking Test. Main outcomes were changes in self-reported weekly physical activity, average walking speed (WS) registered during the test and estimated cardiorespiratory fitness (VO2peak) assessed during each visit. Results: Physical activity levels significantly increased and were maintained during the follow-up period (median MET-h/week 3.0, 12.0, and 9.0 at baseline, 6-, and 12 months, respectively; p<0.0001). These results were associated with increasing mean WS (2.9, 3.9, 4.1 km/h, respectively, p<0.0001), and VO2peak (16.9, 20.0, 20.5 mL/kg/min, respectively, p<0.0001). Conclusions: The proposed intervention demonstrated a stable adherence to physically active lifestyle, along with improved walking speed and estimated VO2peak in older patients with ACS. Results therefore highlight the importance of exercise testing and training and provide important information for the development of more efficient and patient-centered exercise-based secondary prevention programs.