Wu Yao, Ren Bao, Li Jing, Chi Liqun, Li Ping, Wu Jiahui
Department of Cardiac Rehabilitation Center, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Department of Minimally Invasive Surgery Center, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
Front Cardiovasc Med. 2025 Jul 31;12:1580442. doi: 10.3389/fcvm.2025.1580442. eCollection 2025.
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.
This retrospective study included 360 patients who underwent isolated off-pump coronary artery bypass (OPCAB, = 240) or minimally invasive direct coronary artery bypass (MIDCAB, = 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.
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, = -3.426, = 0.001), in older patients than younger patients ( = 20.489, < 0.001) and in females than males (150 ± 84 vs. 200 ± 100 meters, = -5.919, < 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.
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.
6分钟步行试验（6MWT）广泛用于评估心肺疾病患者的功能运动能力、治疗效果和预后。然而，其在冠状动脉旁路移植术（CABG）后心脏康复（CR）I期的应用仍有待探索。本研究调查了CABG患者在早期6MWT期间的身体表现，并分析了影响其住院CR期间步行表现的因素。
这项回顾性研究纳入了360例行单纯非体外循环冠状动脉旁路移植术（OPCAB，n = 240）或微创直接冠状动脉旁路移植术（MIDCAB，n = 120）的患者。参与者的中位年龄为63岁（范围：36 - 80岁），包括285名男性和75名女性。研究于2023年11月22日至2024年12月25日进行。具体纳入了术后I期CR期间在5±2天内完成6MWT的患者。
6分钟步行距离（6MWD）的中位数为183±125米（占预测值的33±20%）。值得注意的是，OPCAB患者的步行距离明显短于MIDCAB患者（175±125 vs. 200±134米，t = -3.426，P = 0.001），老年患者短于年轻患者（t = 20.489，P < 0.001），女性短于男性（150±84 vs. 200±100米，t = -5.919，P < 0.001）。单因素分析显示，6MWD与测试前的身高、体重、体重指数（BMI）、舒张压（DBP）和外周血氧饱和度（SpO2），以及测试后的心率（HR）、收缩压（SBP）、DBP、SpO2和呼吸频率（RR），以及测试期间HR和RR的平均值显著相关。逐步多因素回归分析确定，性别、手术类型、测试结束时的HR和RR以及测试前的DBP是6MWD的独立预测因素。
本研究首次描述了CABG患者在CR I期的早期6MWD。6MWT在CABG术后不久的成人和老年患者中是可行的且耐受性良好。这些发现为影响步行距离的因素提供了有价值的见解，有助于临床评估并为出院后II期CR计划的制定提供参考。
