Die Auswirkungen eines präoperativen aeroben Ausdauertrainings bei alten Patienten (CAB,>70 Jahren) mit Indikation zu einer Bypass-Operation auf die Entwicklung der Gefäßelastizität und Endothelfunktion (EndoPAT, Pulswellenanalyse), der funktionalen Kapazität (6 MWT), der Lebensqualität und der Aktivität des täglichen Lebens (ADL)

Introduction: The majority of patients awaiting coronary artery bypass graft surgery (CABG) are physically inactive to avoid further risks. Aim of this randomized controlled trail was to investigate the effect of a preoperative supervised two week endurance training on the pre-, peri- and postoperative outcomes of patients awaiting elective CABG. Methods: 203 patients (21 female; 182 male; 67.1 ± 8.4 years) were randomly assigned to either an intervention group (IG, n = 88, 9 female; 79 male; 66.1 ± 9.0) or a control group (CG, n = 115, 12 female; 103 male; 67.9 ± 7.9 years). There has been no major significant difference between the groups at baseline. 59 patients (25,7%) did not finish the study for reasons not related to preoperative intervention. Patients of IG participated in a preoperative aerobic endurance exercise program on a cycle ergo- meter with monitioring with six training sessions within two weeks. Exercise intensity was 70% of VO2peak. Patients of CG were physically inactive. At baseline (T1), one day before surgery (T2), at the beginning (T3) and at the end (T4) of cardiac reha- bilitation (CR) measurements of endothelial function using finger plethysmography (peripheral arterial tonometry [PAT]), pulse wave analysis (values obtaine by Mobil-O- Graph®) as well as cardiopulmonary exercise test, six minute walking test (6MWD) and timed up and go test (TUG) were performed. In addition patients were asked to fill in following questionnaires: the MacNew questionnaire for quality of life (QoL), the HADS- D for anxiety and depression and the MOSES for mobility and self-care. Results: In the IG the preoperative aerobic exercise training was well tolerated. No adverse symptoms occurred during exercise sessions. In both groups functional ca- pacity improved significantly during preoperative period. The benefits were significantly more pronounced in the IG (6MWD IG: Δ 50.5 m, p < 0.001; CG: Δ 14.2 m, p < 0.001; p = 0.003; TUG: IG: Δ 0.8 s, p < 0.001; CG: Δ 0.1 s, p < 0.001; p = 0.018). During the preoperative period significant interaction between groups was also found in systolic and diastolic BP with greater benefits in the IG (systolic BP: IG: Δ 8.2 mmHg, p < 0.001; CG: Δ 3.2 mmHg; p < 0.001; p = 0.020; diastolic BP: IG: Δ 5.6 mmHg, p < 0.001; CG: Δ 1.2 mmHg, p < 0.001; p = 0.003). Significant interaction between groups during preoperative period was found in all domains of QoL too. IG was showing more pronounced improvements than CG (IG: Δ 0.3 - 0.4, p ≤ 0.001; CG: Δ 0 - 0.1; p ≤ 0.001; p < 0.001). Similar and sustained effects could be demonstrated in the postoperative period with better developments in 6MWD (T1 vs. T3: IG: Δ -64.7 m; CG: Δ -100.8 m; p = 0.013; T1 vs. T4: IG: Δ +47.2 m; CG: Δ +5.7 m; p < 0.001) and TUG (T1 vs. T3: IG: Δ +1.4 s; CG: Δ +2.6 s; p = 0.003) in IG compared to CG. An age-related analysis of over 70 years old patient showed no significant interaction but significant lower values in diastolic BP (T1, T2, T4: p < 0.01), central diastolic BP (T1, T2, T4: p < 0.02), 6MWD (T3, T4: p < 0.02), cardiopulmonary exercise test (Wattmax, T1-T4: p < 0.05; VO2peak, T1-T4: p < 0.02), anxiety score (T1-T3: p < 0.04) and higher ones in TUG (T1-T4: p < 0.001), pulse wave velocity (T1-T4: p < 0.001) and mobility and self care in the item „moving around using equipment“ (T4: p < 0.02) in comparisson to younger patients. The preoperative exercise training had no impact on the endothelial function, pulse wave analysis or the results of cardiopulmonary exercise test. Furthermore no significant changes were found in questionnaires for anxiety and depression or mobility and self-care. Discussion: A short-term endurance training in elderly patients (> 67 years) with stable coronary artery disease awaiting CABG is feasible and effective to improve preoperative functional capacity (6MWD, TUG), hemodynamic parameters, quality of life and to show even positive effects in CR in 6MWD and TUG. Further studies are needed to evaluate the efficacy of a prerehabilitation with longer duration (2 - 4 weeks) and/or a combined relaxation program, psychological treatment and individually dosed strength and aerobic exercise training. The focus of prerehabilitation in elderly patients should be set on enhancement of functional capacity in phase II CR to prevent care dependency and support the possibility of independant living.