Beneficial Effects of Delayed Opening the Infarct -related Artery on Late Phase Left Ventricular Function in Acute Anterior Myocardial Infarction

Objectives To assess the effect of delayed opening the infarct - related artery(IRA) by percutanous coronary intervention (PCI) on the late phase left ventricular function after acute anterior myocardial infarction. Methods 64 patients with initial Q -wave anterior myocardial infarction and the infarct- related arteries were total occluded conformed by angiogram at 2 to 14 days after onset were divided into successful PCI group and control group (not receiving PCI or the IRA not re - opened). 2 - DE was performed at early phase ( about 3 weeks) , 2 and 6months after onset of AMI respectively to detect the left ventricular function and left ventricular wall motion abnormality (VWMA). The total congestive heart failure events were recorded during 6 months follow-up. Results VWMA scores, left ventricular ejection fraction (LVEF), left ventricular end - diastolic and end-systolic volume indices (LVEDVI and LVDSVI)were similar in 2 groups at early phase and 2 months.There were no differences between early phase and 2months in each group too. VWMA scores and LVEF did not changed at 6 months in each group compared with the early phase and 2 months (P ＞ 0.05 ). But LVEDVI and LVESVI were significantly smaller in the successful PCI group than in the control group (P ＜0.01,P ＜ 0. 05 ). The congestive heart failure events were taken place in 19% of patients in control group compared with 2% in successful PCI group ( P ＞ 0.05 ).Conclusions Although the infarct size does not changed, delayed opening the IRA has beneficial effect to the late phase left ventricular dilatation after acute anterior myocardial infarction.