Association of <i>β</i>-Blocker Therapy at Discharge with Clinical Outcomes after Acute Coronary Syndrome in Patients without Heart Failure
Yan Chen, Xiaofang Tang, Run-lin Gao, Yuejin Yang, Bo Xu, Jinqing Yuan
Abstract
Aim . To evaluate the clinical impact of β -blocker in patients with adequate left ventricular ejection function (LVEF) who underwent percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS). Methods . A total of 10,724 consecutive patients who underwent PCI throughout 2013 were prospectively enrolled in the study. Among these, we analyzed 5,631 ACS patients who were discharged with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mtext>LVEF</mml:mtext><mml:mo>≥</mml:mo><mml:mn>40</mml:mn><mml:mi>%</mml:mi></mml:math>. Patients were then compared according to the β -blocker prescription at discharge. Results . During a 2-year follow-up, no significant association was observed of β -blocker use with all-cause mortality (with β -blockers 47/5,043 (0.9%) vs. without β -blocker use 8/588 (1.4%); hazard ratio (HR) 0.762, 95% confidence interval 0.36 to 1.64; <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.485</mml:mn></mml:math>), cardiac death, myocardial infarction (MI), or major adverse cardiovascular and cerebrovascular events. Subgroup analysis demonstrated that the β -blocker use at discharge reduced the 2-year mortality in patients with unstable angina (UA) (HR 0.42, 95% CI 0.19 to 0.94, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.034</mml:mn></mml:math>). Landmark analysis at 1 year showed that patients with UA who were discharged with β -blockers had lower mortality (HR 0.17, 95% CI 0.04-0.65, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.010</mml:mn></mml:math>) and cardiac death (HR 0.12, 95% CI 0.01-0.99, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M5"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.049</mml:mn></mml:math>) than those discharged without β -blockers. However, the benefit was lost beyond 1 year. No differences in outcomes were recorded in the AMI or overall population. Conclusions . We present that β- blocker significantly lowers the rate of all-cause death up to 1 year, in UA patients who have undergone PCI and have adequate LVEF. Its role in patients with AMI also deserves further exploration.