Effects of β-blockers on left ventricular remodeling in patients with preserved ejection fraction after acute myocardial infarction

Background: The effects of beta-blockers on left ventricular (LV) remodeling have been established in patients with reduced ejection fraction (EF) after acute myocardial infarction (AMI). In AMI patients with preserved EF, additional effects of beta-blockers on reperfusion therapy and current medical treatment have not been elucidated. Methods: Patients with preserved EF (>= 40%), who underwent percutaneous coronary intervention (PCI) for AMI and obtained complete coronary revascularization were enrolled retrospectively. These were divided into groups treated with or without beta-blockers at discharge. Echocardiography was performed on admission and 8 months after PCI to observe LVEF, LV end diastolic volume index (LVEDVI), LV end systolic volume index (LVESVI), LV end diastolic diameter (LVDd), and LV end systolic diameter (LVDs). Results: A total of 114 patients were enrolled; 81 were treated with beta-blockers (beta-blocker group) and 33 were treated without beta-blockers (non-beta-blocker group). All patients were prescribed antiplatelets and 96% took either an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker. At follow-up, EF improved in both groups (2.6% in the beta-blocker group and 4.6% in the non-beta-blocker group). In the beta-blocker group, neither LVEDVI nor LVESVI decreased. However, both LVEDVI (-4.3 ml/m(2)) and LVESVI (-4.1 ml/m(2)) improved in the non-beta-blocker group. There were significant increases in LVDd (2.1 mm) and LVDs (2.2 mm) in the beta-blocker group, whereas these parameters did not significantly change in the non-beta-blocker group. Conclusions: Effects of beta-blockers on LV remodeling were uncertain in AMI patients with preserved EF, who obtained complete coronary revascularization and received optimal medical treatment. (C) 2016 Elsevier Ireland Ltd. All rights reserved.