Long-term effect of β-blocker in ST-segment elevation myocardial infarction in patients with preserved left ventricular systolic function: a propensity analysis.

The current guidelines for acute myocardial infarction (AMI) recommended that β-blocker should be used in patients with decreased left ventricular (LV) systolic function for long-term period. However, the effect of β-blocker in AMI patients with preserved LV systolic function is uncertain. We sought to assess the long-term effect of β-blocker in AMI patients with preserved LV systolic function. During the follow-up period (1997-2011), total 3508 patients were performed percutaneous coronary intervention (PCI). Of these patients, 424 AMI patients with preserved LV systolic function [ejection fraction (EF) > 40 %] were analyzed. Median follow-up period was 4.7 years. Then, patients were divided into two groups (β-blocker group 197 patients and no-β-blocker group 227 patients). However, there are substantial differences in baseline characteristics between two groups. Therefore, we calculated propensity score to match the patients in β-blocker and no-β-blocker groups. After post-match patients (N = 206, 103 matched pair), β-blocker therapy significantly reduced cardiac death compared with no-β-blocker [hazard ratio (HR) 0.40, p = 0.04], whereas β-blocker therapy was not associated with major adverse cardiac events (MACE) and all-cause death. β-Blocker is an effective treatment for AMI patients who underwent PCI with preserved LV systolic function.