The Clinical Characteristics And Prognosis In Early Onset ST-segment Elevation Myocardial Infarction

Objective:To observe the incidence and predictors of major adverse cardiac events(MACE) and also the clinical characters in patients of early onset ST-segment elevation myocardial infarction(STEMI).Method: 3351 consecutive patients who were diagnosed as STEMI and underwent PCI in cardiology department in general hospital of Shenyang military region between July 2008 and December 2012 were retrospectively analyzed in the present observational study. The patients were divided into three groups according to their age: 381 young patients(18-45 years old), 1047 middle-aged patients(46-55 years old for male, 46-65 years old for female) and 1923 elder patients(>55 years old for male, >65 years old for female). Clinical characteristics, the incidence of MACE during hospitalization and follow-up and cumulative hazards of MACE were observed and estimated. The primary indicator was the incidence of MACE, defined as a composite of death, myocardial infarction(MI) or target vessel revascularization(TVR), determined by Kaplan-Meier analysis.Results: The results of clinical character analysis showed that the majority of patients with early onset STEMI were males and complicated with higher BMI, rapid heart rate and also higher diastolic blood pressure. Smoking, drinking, hyperlipidemia, hypertension and family history of coronary heart disease were frequently observed in patients with early-onset STEMI, especially in the group of youth which had statistically difference compared with the other two groups(P <0.01). The incidence of accompanied disease(including stroke, heart failure, cardiogenic shock, renal insufficiency, etc.) were dramatically higher in elder patients and the difference was also statistically significant among the three groups(P <0.05). Allpatients underwent clinical follow-up at least once, with an average follow-up time of 406 [179, 892] days.The incidences of MACE among the three groups were significantly different(7.9%vs5.2%vs7.4%,P=0.045;2.9%vs1.3%vs4.3%, P<0.001), among which the difference on all-cause mortality was statistically significant(6.4% vs 2.9% vs 7.9%, P<0.001), while no obvious difference were found on TVR(6.3% vs 5.1% vs 4.8%, P=0.361) and MI(2.3% vs 1.7% vs 2.4%, P=0.225).The incidence of all-cause death was markedly higher in young patients compared to that in middle-aged ones(6.4% vs. 2.9%,P=0.040), but similar with that in elder patients(6.4% vs. 7.9%, P=0.171). The incidence of MACE in middle-aged patients was significantly lower than that in elder patients(9.6% vs. 12.2%, P=0.008). No difference on MACE could be observed between middle-age and elder patients, even though a tendency of decrease in the former(11.4% vs. 9.6%, P=0.118). Multivariates analysis showed that heart rate, renal insufficiency, anemia, diabetes and family history of coronary heart disease were independent risk predictors of MACE in patients with early-onset STEMI, among which, renal insufficiency was specific predictor for young patients, with heart rate for middle-aged patients and age, female, anemia, history of diabetes for elder-patients.Conclusion: Early-onset STEMI was more common in males, with a high proportion of controllable risk factors(such as somking,drinking and hyperlipidemia) and family history of coronary heart disease but rarely complicated with hypertension, diabetes, cardiac or renal dysfunction, as well as multi-vessel disease.The incidence of 3-year mortality and MACE was markedly higher in young patients compared to that in middle-aged patients, but similar with that in elder patients.