Cardiovascular effects of preferred HOMe-based EXercise training and extended adherence measures in systolic heart failure

Abstract Background Heart failure with reduced ejection fraction (HFrEF) remains a significant burden for patients and health care systems. While exercise training (ET) may improve cardiorespiratory fitness and quality of life for patients with this syndrome, adherence to these interventions remain challenging. Purpose The primary objective of the HOMEX-HF-Pilot trial was to determine whether an individualized ET program combining center- and home-based ET with preferred training elements was superior to standard therapy regarding cardiorespiratory fitness in patients with chronic HFrEF. Methods The HOMEX-HF-Pilot trial enrolled 93 patients with HFrEF (NYHA classes II or III). Main inclusion criteria were LVEF of ≤ 40% at baseline, heart failure symptoms and stable pharmacological heart failure therapy eight weeks prior to intervention. Patients were randomized in a 1:1:1 ratio to 3 groups: 1: usual care (UC), 2: UC + ET, 3: UC + ET + measures to increase adherence. The primary outcome was oxygen consumption at the anaerobic threshold (VO2@AT) from baseline to follow up (month 9) assessed using cardiopulmonary exercise testing. Secondary outcomes included VO2peak and Watt max. In addition to UC, patients randomized to ET (group 2 and 3) performed supervised ET in the training center for 12 weeks with an increasing amount of home-based ET sessions starting in week 8 (in total a minimum of 3 times per week). The ET started with moderate intensity continuous training (MCT) on ergometer bike or treadmill for the first two weeks. Starting in week 3 with aerobic interval training (AIT). After week 4 sports like gymnastics, resistance training, brisk walking or Nordic walking were introduced once a week. Participants were encouraged to proceed with preferred training modalities. ET intensity was defined by heart rate zones determined by CPET and monitored via heart rate monitors. Results Study participants were on average 63 years (SD 10) old with 80% being male. After 9 months of ET VO2@AT was similar between groups (UC: 8.26; EX: 9.00; group 3: 9.22 ml/min/kg). However, VO2peak/kg was greater in EX (16.83ml/min/kg) and group 3 (17.36ml/in/kg) compared to UC (15.53 ml/min/kg). Similarly, the maximal workload was also higher in EX (130 W) and group 3 (130 W) compared to UC (111 W). Conclusion(s) Patients randomized to ET, irrespective of additional measures to improve adherence, had higher peak exercise capacity after 9 months. Training was safe, participants did not experience major training related events. The additional adherence measures did not show additional benefit for CPET measures at month 9. In this heart failure patient collective burdened with musculoskeletal problems (lower back pain, knee pain) and other comorbities 78% of patients managed to perform 9 month of ET and only 4 patients discontinued training due to worsened health conditions. Overall, individualized ET programs may help patients with HFrEF to improve their exercise capacity.