Discontinuation of Beta-Blocker Therapy after Myocardial Infarction.

Methods

We conducted an open-label, randomized, noninferiority trial at 25 centers in South Korea.

我们在韩国的25个中心进行了一项开放标签、随机、非劣效试验。

Patients whose condition remained stable after a myocardial infarction, who had a left ventricular ejection fraction of at least 40% and no heart failure, and who had received beta-blocker therapy for at least 1 year after the myocardial infarction were randomly assigned in a 1:1 ratio to discontinue or to continue beta-blocker therapy.

在心肌梗死后病情保持稳定的患者，左心室射血分数至少为40%且无心力衰竭，并且在心肌梗死后至少接受了1年β受体阻滞剂治疗的患者，以1:1的比例随机分配，以停止或继续β受体阻滞剂治疗。

The primary end point was a composite of death from any cause, recurrent myocardial infarction, or hospitalization for heart failure.

主要终点是全因死亡、复发性心肌梗死或因心力衰竭住院的复合终点。

The prespecified noninferiority margin was an upper limit of the 95% confidence intervalfor the hazard ratioof 1.4.

预设的非劣效性边界是风险比的95%置信区间的上限为1.4。

Results

A total of 2540 patients underwent randomization; 1246 were assigned to beta-blocker discontinuation and 1294 to beta-blocker continuation.

共有2540名患者进行了随机分组；1246名被分配至β受体阻滞剂停药组，1294名被分配至β受体阻滞剂继续使用组。

The mean age of the patients was 63.2 years, and 12.8% were women.

患者的平均年龄为63.2岁，其中12.8%为女性。

At a median follow-up of 3.1 years (interquartile range, 2.5 to 3.5), a primary end-point event had occurred in 58 patients (4-year Kaplan-Meier estimate, 7.2%) in the discontinuation group and in 74 patients (4-year Kaplan-Meier estimate, 9.0%) in the continuation group (hazard ratio, 0.80; 95% confidence interval, 0.57 to 1.13; P = 0.001 for noninferiority).

中位随访时间为3.1年（四分位数范围，2.5至3.5年），在停药组中有58名患者（4年Kaplan-Meier估计值，7.2%）和在继续治疗组中有74名患者（4年Kaplan-Meier估计值，9.0%）发生了主要终点事件（风险比，0.80；95%置信区间，0.57至1.13；P=0.001，用于非劣效性检验）。

The incidenceof serious adverse events was similar in the two groups.

两组中严重不良事件的发生率相似。

Conclusions

Among patients who received beta-blocker therapy beyond the first year after a myocardial infarction, discontinuation of beta-blocker therapy was noninferior to continuation with respect to a composite of death from any cause, recurrent myocardial infarction, or hospitalization for heart failure.

在那些在心肌梗死后第一年之后继续接受β阻滞剂治疗的患者中，停止β阻滞剂治疗与继续治疗相比，在死亡、复发性心肌梗死或因心力衰竭住院的复合终点方面是非劣效的。

(Funded by Patient-Centered Clinical Research Coordinating Center in the Ministry of Health and Welfare, South Korea; SMART-DECISION ClinicalTrials.gov number, NCT04769362.).

(由韩国卫生福利部患者为中心的临床研究中心资助; SMART-DECISION ClinicalTrials.gov编号, NCT04769362.)