[Prognostic effects on percutaneous coronary intervention of different time windows in patients with acute myocardial infarction].

OBJECTIVE: To compare the prognostic effects of different time windows on initiating PCI (percutaneous coronary intervention) in AMI (acute myocardial infarction) patients. METHODS: Ninety-five AMI patients undergoing PCI were enrolled continuously from January 2007 to September 2008. According to the timing of direct PCI, the patients were divided into 3 groups: after AMI, < 6 h (Group A, n = 45), 6 - 12 h (Group B, n = 45) and 12 - 24 h (Group C, n = 35). Comparisons were made among these 3 groups in terms of the post-PCI incidence of heart failure and mortality. The left ventricular ejection fraction (LVEF) and left ventricular end-diastolic inside diameter (LVEDV) were measured by echocardiogram at Month 6. RESULTS: During the hospitalization and follow-up, Group A had a lower incidence of heart failure and mortality than Groups B and C. And Group B had a lower rate than Group C. The difference was significant (P < 0.05). Compared with LVEF(%) (52.25 ± 4.27) in Group B and LVEF (%) (47.75 ± 6.86) in Group C, LVEF(%) (57.51 ± 6.9) in Group A were significantly improved on ECG at Month 6 months. LVEDV (mm) (45.89 ± 4.23) in Group A were significantly lower than LVEDV (mm) (49.0 ± 3.1) in Group B and LVEDV (mm) (52.46 ± 4.9) in Group C. The differences were both statistically significant (P < 0.05). CONCLUSION: An early time windows of initiating PCI in AMI patients can significantly improve the left ventricular functions and reduce the incidence of heart failure, left ventricular remodeling and the mortality rate. All these measures could improve left ventricular functions and prognosis.