BENEFICIAL-EFFECTS OF EARLY CORONARY REPERFUSION ON LEFT-VENTRICULAR REMODELING AND SYSTOLIC FUNCTION IN PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION

Objective To evaluate the beneficial effects of early coronary reperfu sion on left ventricular remodeling (LVRM) and systolic function in pa tients with acute myocardial infarction (AMI). Methods Eighty-one pati ents with first AMI in the convalescent stage and having undergone lef t ventriculography (LVG) and coronary arteriography (GAG) were divided into four groups: the anterolateral wall (ALW) myocardial infarction (MI) non-reperfusion (n = 20) and reperfusion (n = 21), and inferopost erial wall (IPW) MI non-reperfusion (n = 20) and reperfusion (n = 20), according to infarct location and early treatment with or without suc cessful coronary reperfusion therapy within 6 hours after onset of sym ptoms. By LVG, the parameters of LVRM and systolic function in the fou r MI groups were analyzed and compared with those in normal group (n = 25) and between the two reperfusion and non-reperfusion MI groups. Re sults In both ALW and IPW MI non-reperfusion groups, the left ventricu lar (LV) end-diastolic volume (EDV), circumference (EDC), short-axis d imension (EDD), short to long axis ratio (ED-D/L), sphericity index (E D-SI) and end-systolic volume (ESV) were all significantly increased ( P < 0.01-0.001), while LV ejection fractions (LVEF) were significantly decreased (both P < 0.001) when compared with those of normal group; and the increase in ESV and decrease in LVEF were both significantly g reater in ALW than in IPW MI groups (both P < 0.01). In both ALW and I PW Mi reperfusion groups, however, the EDV, EDD, ESV, as well as the e xtent and severity of regional wall motion abnormality (RWMA) were sig nificantly smaller (P < 0.05-0.001), while LVEF were significantly hig her (P < 0.01-0.001) when compared with those in the two non-reperfusi on MI groups respectively. There were no longer significant difference s in LVEF and ESV between ALW amd IPW MI groups (both P > 0.05). The E DC in IPW MI reperfusion group and the ED-D/L and ED-SI in ALW MI repe rfusion group were also significantly reduced compared with those in t he two non-reperfusion MI groups respectively (P < 0.05-0.001). All th e above parameters in the two reperfusion MI group were decreased to t he normal in comparison with normal group except ESV and LVEF, and ED- D/L and ED-SI in IPW MI group. Conclusion It was indicated that in bot h ALW and IPW MI non-reperfusion groups, LVRM had occurred in convales cent stage of AMI with an increase in EDV and EDC, spherical change in LV shape, and accompanying reduction in LV systolic function; and ear ly coronary reperfusion in AMI could reduce the extent and severity of RWMA, prevent from LV enlargement and remodeling, and preserve or imp rove LV systolic function with more prominence in ALW MI.