PURPOSE: Our aim was to comparatively assess the impact of ACE-I and/or beta-blockers on 3-year mortality in patients with or without impaired left ventricular (LV) function undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).
METHODS: The analysis included 4425 patients admitted for primary PCI during 2009 – 2015 from a prospective, electronic registry of a high-volume tertiary center, who survived initial hospitalization, and for whom information on LV function and discharge medication were available. Patients were stratified according to LV systolic dysfunction, defined as LVEF <40%. Unadjusted and adjusted Cox regression models were created to investigate the impact of beta-blocker and/or ACE-I therapy on 3-year mortality.
RESULTS: 22.9% (n=1013) had LV dysfunction, 23.0% (n=1017) received either an ACE-I or a beta-blocker and 72.2% received both medications at discharge (n=3197). The concurrent use of both ACE-I and beta-blockers was not different in LVEF=40% vs. LVEF<40% (72.4% vs. 71.7%, p=0.43). The use of at least one of the guideline-recommended medications was associated with a significantly lower 3-year mortality in both patients with LVEF=40% (18.7% if neither was used, 11.2% if either a beta-blocker or an ACE-I were used and 9.4% if both were used, p=0.001), and LVEF<40% (55.4% if neither was used, 32.5% if either a beta-blocker or an ACE-I were used and 22.9% if both were used, p<0.001) (Figure). After adjusting for significant mortality predictors including older age, diabetes, hypertension, renal failure, previous stroke, Killip class =2 and non-culprit chronic total occlusion (CTO), the concurrent use of both a beta-blocker and an ACE-I remained independently associated with lower 3-year mortality in both patients with LVEF<40% (HR 0.30, p<0.001) and LVEF=40% (HR=0.41, p=0.001). The use of a single agent was independently associated with lower mortality in patients with LVEF<40% (HR 0.45, p=0.002), but not in patients with LVEF=40% (HR 0.61, p=0.07).
CONCLUSIONS: Guideline-recommended use of both a beta-blocker and an ACE-I in post-MI patients was associated with a lower 3-year mortality regardless of the LV function, whereas using only one of the two agents was associated with improved prognosis only in patients with LV dysfunction, but not in patients without LV impairment.