Department of Cardiac Surgery, First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
School of Mathematics, Sun Yat-sen University, Guangzhou, China.
J Thorac Cardiovasc Surg. 2024 Nov;168(5):1462-1471.e7. doi: 10.1016/j.jtcvs.2023.09.021. Epub 2023 Sep 15.
We aim to evaluate the heterogeneous treatment effects of coronary artery bypass grafting in patients with ischemic cardiomyopathy and to identify a group of patients to have greater benefits from coronary artery bypass grafting compared with medical therapy alone.
Machine learning causal forest modeling was performed to identify the heterogeneous treatment effects of coronary artery bypass grafting in patients with ischemic cardiomyopathy from the Surgical Treatment for Ischemic Heart Failure trial. The risks of death from any cause and death from cardiovascular causes between coronary artery bypass grafting and medical therapy alone were assessed in the identified subgroups.
Among 1212 patients enrolled in the Surgical Treatment for Ischemic Heart Failure trial, left ventricular end-systolic volume index, serum creatinine, and age were identified by the machine learning algorithm to distinguish patients with heterogeneous treatment effects. Among patients with left ventricular end-systolic volume index greater than 84 mL/m and age 60.27 years or less, coronary artery bypass grafting was associated with a significantly lower risk of death from any cause (adjusted hazard ratio, 0.61; 95% CI, 0.45-0.84) and death from cardiovascular causes (adjusted hazard ratio, 0.63; 95% CI, 0.45-0.89). By contrast, the survival benefits of coronary artery bypass grafting no longer exist in patients with left ventricular end-systolic volume index 84 mL/m or less and serum creatinine 1.04 mg/dL or less, or patients with left ventricular end-systolic volume index greater than 84 mL/m and age more than 60.27 years.
The current post hoc analysis of the Surgical Treatment for Ischemic Heart Failure trial identified heterogeneous treatment effects of coronary artery bypass grafting in patients with ischemic cardiomyopathy. Younger patients with severe left ventricular enlargement were more likely to derive greater survival benefits from coronary artery bypass grafting.
我们旨在评估冠状动脉旁路移植术在缺血性心肌病患者中的异质性治疗效果，并确定一组患者相较于单纯药物治疗可从冠状动脉旁路移植术中获得更大获益。
我们采用机器学习因果森林模型，对缺血性心肌病患者进行了来自“外科治疗缺血性心力衰竭试验（Surgical Treatment for Ischemic Heart Failure trial）”的冠状动脉旁路移植术异质性治疗效果的评估。在确定的亚组中，评估了冠状动脉旁路移植术与单纯药物治疗相比的全因死亡风险和心血管原因死亡风险。
在“外科治疗缺血性心力衰竭试验”纳入的 1212 例患者中，机器学习算法识别出左心室收缩末期容积指数、血清肌酐和年龄可区分具有异质性治疗效果的患者。在左心室收缩末期容积指数大于 84mL/m 和年龄 60.27 岁或更小的患者中，冠状动脉旁路移植术与全因死亡风险显著降低相关（校正后危险比，0.61；95%置信区间，0.45-0.84）和心血管原因死亡风险（校正后危险比，0.63；95%置信区间，0.45-0.89）。相比之下，在左心室收缩末期容积指数 84mL/m 或更小且血清肌酐 1.04mg/dL 或更小，或左心室收缩末期容积指数大于 84mL/m 且年龄大于 60.27 岁的患者中，冠状动脉旁路移植术的生存获益已不复存在。
目前对“外科治疗缺血性心力衰竭试验”的事后分析确定了缺血性心肌病患者冠状动脉旁路移植术的异质性治疗效果。严重左心室扩大的年轻患者更有可能从冠状动脉旁路移植术中获得更大的生存获益。
