Determinants of Improvement of Mid-term Ejection Fraction in Patients with Acute Myocardial Infarction

Abstract

Persistent severe left ventricular (LV) systolic dysfunction after acute myocardial infarction (AMI) is associated with increased morbidity and mortality, whereas mid-term recovery of LV systolic function after AMI is associated with better long-term outcomes. The purpose of this study was to investigate the determinants of mid-term improvement of LV ejection fraction (EF) in AMI patients. We included 210 AMI patients who had modified Simpson EF both at the index admission and mid-term follow up. The difference of EF between the index admission and mid-term follow-up was calculated in all study patients. The EF improvement group was defined as mid-term ≥ 10% EF increase compared with the index admission EF. Of 210 AMI patients, 46 (21.9%) were allocated to the EF improvement group and 164 (78.1%) to the non-EF improvement group. Brain natriuretic peptide (BNP) at the timing of admission was significantly greater in the EF improvement group (735.8 ± 1077.6 pg/mL) than in the non-EF improvement group (239.0 ± 419.8 pg/mL) (P < 0.001). Multivariate logistic regression analysis revealed that log₁₀ BNP at the timing of admission (OR 3.36, 95% CI 1.69-6.66, P < 0.001) and left main trunk-left anterior descending artery (LM-LAD) as the infarct-related artery (OR 3.34, 95% CI 1.59-7.02, P = 0.001) were significantly associated with EF improvement. In conclusion, elevated BNP at the timing of admission and LM-LAD as the infarct-related artery were significantly associated with mid-term LVEF recovery. Our results support aggressive acute treatment for those severe AMI, because the possibility of mid-term LVEF recovery is greater compared with other AMI.