Long-term Therapeutics Effects Of Varying Treatment Choices In Patients With ST Elevation Acute Myocardial Infarction

Objective:We sought to compare the effect of different treatments on the long-term outcome of acute ST elevation myocardial infarction(STEMI) patients,as well as to evaluate the impact of varying time from symptom onset to reperfusion on long-term prognosis.Moreover,we want to identify the independent predictive factors of STEMI patient in developing MACE.Methods:From January 2004 to July 2007,432 patients treated in the inpatient department of Zhongshan Hospital affiliated to Fudan University were reviewed.(1)According to treatment methods,432 patients were classified into the conservative group(n=115),the immediate PCI group(n=141) and the late PCI group(n=176).The general conditions of the patients in three groups and the PCI information of the immediate and the late PCI group were collected and compared.The primary end-point was the happening of all-cause death,the combined end-point was MACE, including all-cause death,recurrent infarction and the target vessel revascularization. Kaplan-Meier analysis and log rank test were used for univariate analyses of factors predictive of survival and MACE free survival,and multivariate analysis was carried out using the Cox proportional hazards model to determine the variable relevant to survival and MACE free survival.(2) The patients who received immediate PCI was divided into the≤6h group(n=64) and＞6h group(n=77) according to the symptom-onset to balloon time.The end-point was MACE,as it said in part one.The method was the same as part one.The patients who received late PCI was divided into 12h＜t≤1w group(n=50),1w＜t≤2w group(n=75),and t＞2w group(n=51).The end-point was MACE,as it said in part one. The method was the same as part one.Results:(1)The general characteristics of patients were well-balanced in three groups except that age,stroke history,new arrhythmia,cardiac shock,killip class,LVEF, LDL-C and the use of tirofiban and LMWH showed statistically significant difference(P＜0.05).Collateral circulation,the maximal narrowness of IRA,the mean length of stents,and the number of stents were found to be significantly different between the immediate PCI and the late PCI group,and the rest of the PCI information were similar across two groups.After a median follow-up of 30.1 months, treatment choice is associated with mortality(43.2%vs.3.7%vs.7.2%) and were an independent predictor of late survival(P=0.001)by Cox regression.The survival of the immediate PCI or the late PCI group is better than the conservative group(immediate PCI:HR=0.220,P=0.003;late PCI:HR=0.319,P=0.002),though the two PCI groups had no significant impact on the late survival(P＞0.05). Multivariate analysis also revealed that age,stroke history,EF,killip class,the standard use of Clopidogrel were significantly associated with the survival of patients(P＜0.05).Treatment choice is also associated with the occurrence of MACE(45.9%vs.7.4%vs.16.2%) and were an independent predictor of late MACE free survival(P=0.003) by Cox regression.Patients treated with immediate or late PCI had equal MACE free survivals but the immediate group had a better trend(HR=0.490,P=0.062),both of which compared favourably with those in the conservative group(immediate PCI:HR=0.282,P=0.001;late PCI:HR=0.575,P =0.045).Multivariate analysis also revealed that age,stroke history,hyperlipidemia, killip class and the standard use of Clopidogrel were significantly associated with the MACE free survival of patients(P＜0.05).(2) The general characteristics,PCI information of patients and drug use were well-balanced in two immediate PCI groups except that LDL-c and TIMI flow grade 3 after PCI showed statistically significant difference(P＜0.05).Cox regression showed that new arrhythmia,the length of stents,that TIMI flow grade 3 after PCI were independent predictor of MACE free survival.PCI time,multiple vessels involved and the use of statins had a trend to be associated with MACE free survival.The general characteristics,PCI information of patients and drug use were well-balanced in three late PCI groups except that LDL-C,EF,shock,the maximal narrowness of IRA,the number of stents and the standard use of LMWH and Clopidogrel showed statistically significant difference(P＜0.05).Cox regression showed that hyperlipidemia, EF and that TIMI flow grade 3 after PCI were independent predictor of MACE free survival.Conclusions:1)The immediate PCI and late PCI had similar efficacy in treating STEMI patients,but were both superior to the drug treatment and treatment choice was an independent predictor of long-term prognosis 2)Time from symptom onset to balloon had a trend to be associated with MACE free survival in immediate PCI subgroup,but no significant impact on late PCI subgroup.