[Adherence to Phase III Cardiac Rehabilitation Programs: A Prospective, Randomized Comparison between a Conventionally Conducted Program and a Tai Chi-Based Program]. / Adhärenz in Herzgruppen: Ein prospektiver, randomisierter Vergleich einer konventionell durchgeführten Herzgruppe zu einer Tai-Chi-Herzgruppe.

INTRODUCTION: In patients with cardiac diseases, lifestyle changes such as an increase in physical activity are recommended to prevent further cardiac events. In Germany this is possible by attending outpatient heart groups. A problem inherent in these programs is the lack of adherence since more than two thirds of patients stop attending cardiac rehabilitation programs after six months. An alternative to the conventional implementation of heart groups is Tai Chi, which was found to improve adherence to cardiac rehabilitation programs in international studies. METHODS: Patients were randomly assigned to a conventional heart group or a heart group with Tai Chi exercises. At the beginning of the study, a medical history was taken and physical and instrumental tests were carried out, including an assessment of anxiety/depression (HADS questionnaire) and physical well-being (SD-12). Follow-up tests were performed every three months. RESULTS: Patients were 62.6 ±â€Š8.5 years old, the mean BMI was 28.6 ±â€Š62 kg/m(2), and the proportion of women was 29.8 %. The groups were different in terms of age (conventional heart group: 65.0 ±â€Š7.5; Tai Chi group: 59.9 ±â€Š8.9 years). Therefore, age-adjusted analyses were performed in addition to the planned analyses. Regarding the primary endpoint of the study, there was no difference between the groups. After twelve months, 50 % of subjects were active in the Tai Chi group and 48 % in the conventional heart group (odds ratio 0.92, p = 0.891). After adjustment for age by logistic regression, the odds ratio was 0.47 (p = 0.285). Furthermore, both the participation period in weeks (Tai Chi group: 43.3 ±â€Š26.0; conventional group: 45.5 ±â€Š24.2, p = 0.766) and the participation rate (Tai Chi group: 66.8 ±â€Š19.2 % Tai Chi, conventional group: 76.3 ±â€Š16.5 %, p = 0.074) did not differ between the two groups. A further analysis showed a non-significant trend for improvement of anxiety, depression and physical well-being in the Tai Chi group compared with the conventional group. CONCLUSION: The insight gained in international studies regarding a better adherence to Tai Chi-guided prevention programs was not transferable to heart group participants from Germany. However, there was a trend regarding a better mental condition in the Tai Chi group.

Effects of combined therapy of clopidogrel and aspirin in preventing thrombus formation on mechanical heart valves in an ex vivo rabbit model.

BACKGROUND: The aim of our study was to investigate the efficacy of the combination of clopidogrel and aspirin in the prevention of thrombus formation on artificial heart valves in an experimental rabbit model as compared to anticoagulation with warfarin. METHODS: Studies were performed after oral administration of clopidogrel and aspirin in group I (n=9) for 5 days, after 5+/-2 days treatment with warfarin in group II (n=9) and without medication in group III (n=9). Leaflets from Sulzer Carbomedics bileaflet valves were placed in a flow chamber. The flow chamber was filled with blood in a continuous circulation between the carotid artery and the jugular vein. RESULTS: In group III, the flow chamber was clotted after a median of 15 min of circulation. Weight analysis before and after 1 h of perfusion showed that the median thrombus weight was 9.1 mg in group I, 14.4 mg in group II and 33.7 mg in group III. Further analysis by electron microscopy showed fewer platelets and erythrocytes on leaflets in group I than on leaflet surfaces in group II. CONCLUSION: Clopidogrel and aspirin were more effective than warfarin in preventing thrombus formation on artificial heart valve leaflets in our investigation. This rabbit model with a high dosage of clopidogrel and aspirin, and a short-time exposure of the heart valve leaflets to rabbit blood under laminar flow, should be further evaluated with respect to whether it can give information about antithrombotic regimens in patients after mechanical heart valve replacement.