Objective: To investigate the effects of different rehabilitation modalities on cardiopulmonary function in patients with acute coronary syndrome after revascularization.Methods: Two randomized controlled trials were conducted. All patients were stable for more than 48 h and less than 1 week after revascularization for acute coronary syndrome and were randomly assigned to Group A (home-based rehabilitation group) or Group B (center guided home-based rehabilitation group). The cardiopulmonary exercise test was mainly performed before and 3 months after cardiac rehabilitation (at the end of intervention). The primary endpoints of the study were peak oxygen uptake (VO2peak), and the secondary endpoints were maximum metabolic equivalents (METs), anaerobic threshold exercise load (Load AT), maximal workload (Load max), and anaerobic threshold oxygen uptake (VO2 AT).Results: A total of 106 patients were included in the study, with 47 patients in Group A (with 6 losses) and 50 patients in Group B (with 3 losses). There were no significant difference between the two groups in terms of age, gender, body mass index (BMI), left ventricular ejection fraction(LVEF), low-density lipoprotein cholesterol(LDL-C),cardiovascular risk factors. In Group A, no significant differences in CPET indices were observed before and after the intervention. In Group B, values of maximum metabolic equivalents (METs), peak heart rate (PHR), anaerobic threshold exercise load (Load AT), maximal workload (Load max), maximum ventilation per minute (VE max), peak oxygen uptake (VO2peak), anaerobic threshold oxygen uptake (VO2 AT) and maximum oxygen pulse (VO2/HRmax) were higher than those before the intervention (P < 0.05). In addition, METs (max), Load AT, Load max, VO2 AT, and VO2peak in Group B were higher than those in group A (P < 0.05). The change rates of VO2peak, METs(max), PHR, Load max, VO2 AT, VE max, VO2/HR(max) in the two groups were significantly different before and after intervention (P < 0.05).Conclusion: Cardiac exercise rehabilitation is helpful for improving patients’ cardiopulmonary endurance and quality of life. Moreover, rehabilitation modalities with regular hospital guidance can improve cardiopulmonary function in a shorter period,which seems to be more effective than a complete home-based rehabilitation model. Clinical Trial Registration: http://www.chictr.org.cn, identifier (ChiCTR2400081034).

Previous studies have found a significant association between type 2 diabetes (T2DM) and impaired cardiopulmonary fitness (CRF); however, little evidence was shown in patients after percutaneous coronary intervention (PCI). This study aimed to evaluate the independent effects of T2DM on CRF in patients who have undergone successful percutaneous coronary intervention (PCI) and received guideline-directed medical therapy. Additionally, we explored whether this association is influenced by factors such as demographic features, physical activity level, duration of diabetes, time from index PCI, and history of occlusion myocardial infarction. We retrospectively analyzed data from post-PCI patients who consecutively visited the Cardiac Rehabilitation Center at Beijing Anzhen Hospital between September 2023 and July 2024. To isolate the impact of T2DM on cardiovascular fitness, we implemented strict exclusion criteria for confounding comorbidities, particularly heart failure. Cardiorespiratory fitness was quantified through gold-standard measures: peak oxygen uptake (VO2max) and metabolic equivalents (METs). Baseline characteristics were compared between patients with T2DM and non-diabetic patients (DM group vs. non-DM group). A multivariable regression model was used to evaluate the independent effect of T2DM on CRF, adjusting for confounding factors such as demographic features, physical activity level, duration of diabetes, time since index PCI, and residual comorbidities. Subgroup analyses and interaction tests were performed to assess the impact of T2DM across different subgroups. 201 patients (150 non-DM and 51 DM patients) were included in the final analysis. Hypertension was significantly more prevalent in DM patients (68.6 vs. 42.7%, p = 0.001), while other comorbidities, anthropometric measurements, lifestyle factors, and time from index PCI showed no significant differences between groups (all p > 0.05). Multivariate logistic regression analyses demonstrated significant negative associations between T2DM and both VO2max and METs. After adjusting for basic demographic and lifestyle factors (Model 1), T2DM was inversely associated with VO2max (β=−98.3, 95% CI −193.4 to −3.3, p = 0.044) and METs (β=−0.4, 95% CI −0.8 to −0.0, p = 0.05). These negative associations remained robust and became stronger in Model 2, which further adjusted for physical activity status, hypertension, hyperlipidemia, history of occlusion myocardial infarction, time from index PCI, DM duration, and using beta-blockers, showing more pronounced inverse relationships with both VO2max (β=−212.3, 95% CI −389.4 to −35.3, p = 0.02) and METs (β=−0.9, 95% CI −1.6 to −0.2, p = 0.014). Subgroup analyses indicated consistent inverse associations, with no significant effect modification based on sex, age, body mass index (BMI), time since the index PCI, physical activity status, or a history of occlusion myocardial infarction. Our study demonstrates that T2DM is an independent negative predictor of CRF in post-PCI patients, with consistent findings across various subgroups and robust results after adjusting for confounding factors. These findings underscore the importance of CRF assessment in post-PCI patients and highlight the need for targeted interventions to improve CRF in individuals with T2DM.

Background: The 6 min walk test (6MWT) is widely used to evaluate functional exercise capacity, therapeutic effects, and prognosis in patients with cardiopulmonary diseases. However, its application in phase I cardiac rehabilitation (CR) after coronary artery bypass grafting (CABG) remains under explored. This study investigates the physical performance of CABG patients during the early 6MWT and analyzes factors influencing their walking performance during inpatient CR.Methods: This retrospective study included 360 patients who underwent isolated off-pump coronary artery bypass (OPCAB, n = 240) or minimally invasive direct coronary artery bypass (MIDCAB, n = 120) surgery. Participants, with a median age of 63 years (range: 36–80), comprised 285 males and 75 females. The study was conducted from November 22, 2023, to December 25, 2024. It specifically included patients who completed the 6MWT within 5 ± 2 days during phase I CR post-surgery.Results: The median 6 min walk distance (6MWD) was 183 ± 125 meters (33 ± 20% of predicted). Notably, the walking distances were significantly shorter in OPCAB patients than MIDCAB patients (175 ± 125 vs. 200 ± 134 meters, Z = −3.426, P = 0.001), in older patients than younger patients (H = 20.489, P < 0.001) and in females than males (150 ± 84 vs. 200 ± 100 meters, Z = −5.919, P < 0.001). Univariate analysis showed 6MWD significantly correlated with height, weight, body mass index (BMI), diastolic blood pressure (DBP) and peripheral oxygen saturation (SpO2) before the test, as well as heart rate (HR), systolic blood pressure (SBP), DBP, SpO2, and respiratory rate (RR) after the test, and the mean values of HR and RR during the test. The stepwise multivariate regression analysis identified that gender, type of surgery, HR and RR at the end of the test, and DBP before the test were independent predictors of the 6MWD.Conclusion: This study is the first to describe early 6MWD in CABG patients during phase I CR. The 6MWT is feasible and well-tolerated in adults and older patients shortly after CABG. The findings provide valuable insights into factors affecting walking distance, aiding clinical assessment and informing phase II CR program development post-discharge.

Background: Minimally invasive direct coronary artery bypass (MIDCAB) surgery offers advantages over off-pump coronary artery bypass (OPCAB), including reduced trauma and faster recovery. However, differences in perioperative cardiac rehabilitation (CR) outcomes between MIDCAB and OPCAB remain unclear. This study compared perioperative clinical characteristics, surgical features, and CR outcomes in patients undergoing MIDCAB versus OPCAB. Methods: This retrospective cohort analysis included 304 patients (31.2% MIDCAB, 68.8% OPCAB) who participated in a CR program, including the 6-min walk test (6MWT), from November 2023 to December 2024. Results: MIDCAB patients had shorter surgery times, fewer grafted vessels, shorter ventilator-assisted time, less total intraoperative fluid, less bleeding, and shorter postoperative hospital stays (all p < 0.05). After cardiac rehabilitation, MIDCAB patients showed shorter time to 6MWT, longer six-minute walk distance (6MWD) (200 ± 125 vs. 178 ± 125 m), higher 6MWD relative to predicted values, and greater metabolic equivalents (all p < 0.05). The median LVEF of MIDCAB patients was the same as that of OPCAB patients (p < 0.05). Conclusions: Our study demonstrates that MIDCAB patients exhibit superior exercise capacity following cardiac rehabilitation.

Coronary vascular disease (CVD) is the leading cause of mortality worldwide, while type 2 diabetes mellitus (T2DM) coexists in up to 40% of patients with e