Long-time Follow-up Study Of Non-ST-segment Elevation Myocardial Infarction

Long-time follow-up study of non-ST-segment elevation myocardial infarctionBackground:The Acute coronary syndromes(ACS) was first time used in the guideline of Acute Myocardial Infarction in 1996,to describe a group of acute coronary artery ischemia and hypoxia events leading by coronary artery stenosis, obstruction or spasm. Say it ACS can improve clinical attention on acute chest pain patients, especially the unstable angina and non-ST-elevation myocardial infarction patients, both of them have different risk progress to acute ST-elevation myocardial infarction, they can together be called NSTEACS. Recent years, with the rising morbidity of NSTEACS, it has become one of the most important reason of death, disability in developed countries and our nation. NSTEMI is the high-risk patients in NSTEACS, with poor clinical prognosis, so the researches of this part of the patients have particularly important clinical significance.With the deeping research of pathogenesis on CHD, we find a lot of clinical risk factors, which provide theoretical foundation for the secondary prevention, besides the traditional prognostic factors, some new prognostic factors were found, such as blood pressure, heart rate, cardiac and renal dysfunction, but still lacks of multicenter clinical trials to confirme them. therefore. The analysis of various clinical risk factors of the NSTEMI patients can help control these clinical risk factors. There have two treatment strategies in NSTEACS patients, the early conservative treatment and early invasive treatment, according to previous research, NSTEMI patients tend to choose an early invasive strategy, but each of large clinical trials have different condition which made the result controversial. With the strengthening use of antiplatelet therapy and stent, it is necessary to reassess the benefit of early invasive treatment group under new situation.Objective:1. Retrospectively analyze the NSTEMI patients in our hospital recent 6 years, investigate the clinical features and current practice.2. Follow-up the adverse events of NSTEMI patients assess the risk factors for short and long-term prognosis.3. Compare the prognosis of the early invasive and early conservative treatment, including the primary end point and secondary end points. Methods:1.206 patients with NSTEMI which select from the department of Cardiology of our hospital during January 2004 to January 2010, all patients meet the universer criterion of Acute Myocardial infarction in 2007, record the clinical characteristics and treatment during hospitalization.2. All patients were followed up at least 6 months, the primary end point were cardiac death or nonfatal myocardial infarction, the second endpoint was a composite of cardiac death, nonfatal myocardial infarction,revascularization,or rehospitalization.3.142 patients have reached 6 months follow-up and 93 patients reached 2 years follow-up, Cox regression model was used to analyze the association between the end points and multiple risk factors, evaluate the relationship between adverse events and 37 clinical risk factors.4.142 patients were divided into early conservative group and early invasive group, compare the rate of adverse events between two groups, Logistic regression analysis was used to evaluate the value of early treatment strategies. Results:1.206 patients with the proportion of male 69.4%, age between 24～90 years old, mean age (66±12) years old. The traditional risk factors were hypertension72.3%, smoking 37.9%, DM 29.6%, hyperlipidemial2.1%. The clinical history were CAD 50.0%, MI 12.6%, Stroke 14.6%, HF 17.5%, RF 8.3%. Drug use rate were aspirin 86.4%, clopidogrel 42.7%, statin 68.0%, ACEI/ARB 44.7%, beta blockers 55.3%, CCB 20.4%, nitrate 69.9%. Interventional treatment was CAG 58.7%, PCI 34.0%, and CABG 11.7%. Coronary angiography show LM and 3-vessel disease were 22.3%.50.4%.2.142 patients reached 6 months followed-up, there were 20 MACE patients, including 16 cases death(11.3%) and 4 cases nonfatal-MI (2.8%).93 patients reached 2 years follow-up, there were 20 MACE patients, including 15 cases death (16.1%) and 5 cases nonfatal-MI (5.4%).3.Cox regression analyze show that the most important baseline determinants of short-term outcomes were age, signs of heart failure, signs of renal failure, aspirin; the most important baseline determinants of long-term outcomes were age, signs of heart failure, signs of renal failure, aspirin and early invasive treatment. Determinants of mortality were generally also predictive of death or myocardial infarction.4.142 patients divided into early invasive group (n=82) and early conservative group (n=60), all patients were followed up at least 6 months. There was a decrease in the primary endpoint in early invasive group compared with the conservative group(7% vs.23%, p=0.007),cardiac death was significantly lower in early invasive group(5% vs.20%, p=0.005),nonfatal myocardial infarction rate was the same in two groups, the composite endpoint rate was lower in early invasive group, but no significance(27% vs.37%, p=0.211).Conclusions:1. NSTEMI patients was always aged patients, male, common with clinical history of hypertension, diabetes, smoking, especially the diabetes proportion was high. Patients often with HF and had a bad outcome during both in-hospital and outside. Drug use rate such as aspirin, clopidogrel, statins, ACEI/ARB,β-blockers, CCB were lower, but interventional treatment proportion was higher than other areas in China.LM and 3-vessel also have high proportion.2. Patients with NSTEMI have poor outcomes. age, signs of heart failure and renal failure are most important risk factors, while aspirin is an important protection factor, and early intervention can significantly improve patients with long-term prognosis.3. An early invasive strategy was superior to an early conservative strategy in patients with acute non-ST-segment elevation myocardial infarction, with a significant reduction in mortality.