Effects Of Various Preinfarction Angina On Prognosis In Patients With Acute Myocardial Infarction

Objectives:To explore the effects of different course of preinfarction angina(PA) on prognosis in patients with first acute ST-segment-elevated myocardial infarction (ASTEMI),through the study of clinical materials for 300 patients with preinfarction angina.We expect to find the suitable opportunity of treating angina pectoris and to disscuss the value on preventing AMI and improving the prognosis.Methods:All 326 patients with acute myocardial infarction(AMI) were hospitalized patients in the Medical Department of Cardiology of the Fouth People's Hospital of Jinan from the year 2001 to 2006 consecutively.An average period of followed up time is 31.05±14.26 months.The following up rate was 92.02% and 300 patients were enrolled.All 300 patients were assigned to three groups according to different course of PA history:①Long-term PA group (abbreviated as group A):PA history more than 30 days(151 patients); PA history less than 7 days(116 patients).②Medium-term PA group (abbreviated as group B):PA history more than 7days and less than 30 days(33 patients);③Short-term PA group(abbreviated as group C):The short and long-term prognosis (complication, short and long-term incidence of major adverse cadiac event) were compared retrospectively. All of these data underwent statistics test by SAS8.12 software,p<0.05 should be think has the significant difference in statistics.Results:①In group A,the percent of complicating primary hypertension and diabetes mellitus were much higher than that in group C(P<0.01).In group C, the incidence of addiction for smoking was higher than that in group A(P<0.01).In group B,there was no significant difference in complicating primary hypertension, diabetes mellitus and addiction for smoking with other two groups(P>0.05).There had no significant difference about sex,age and complicating hyperlipemia among three groups(P>0.05).②In group A, the incidence of large size infarction, inferoposterior wall and/or right ventricular infarction and accepting PCI after first ASTEMI were much lower than that in group C(P<0.01).The incidence of extensive anterior wall infarction,anterior and inferior wall infarction,the percent of thrombolysis therapy and thrombolytic were no significant difference among three groups(P>0.05).③In group A, the peak of creatine kinase,creatine kinase MB and cardiac troponin T were much lower than that in group B and C(P<0.05),while left ventricular ejection fraction was higher than that in group B and C(P<0.05).Those data were not significantly different between the group B and C.Level of the cholesterol and blood glucose were not significantly different among three groups.④In group A,the incidence of ventricular aneurysm was higher than that in group C (P<0.01).In group C,the incidence of acute cardiac failure (Killip class≥Ⅱgrade), cardiogenic shock, auriculo-ventricular block more thanⅡdegreeⅡtype and postinfarction angina were much higher than that in group A(P<0.01). In group B,those indexes mentioned above were not significantly different with other two groups.The incidence of severe cardiac arrhythmias, frequent ventricular premature beats,ventricular tachycardia/fibriltion,atrial tachycardia/ new developed atrial fibrillation,serious sinus bradycardia and in-hospital mortality after first ASTEMI were not significantly different among three groups.⑤There were 130 patients in all that had accepted the coronary angiography(CAG) in three groups. In group A,the incidence of single vessel lesion was lower than that in group C for patients who had accepted CAG(P<0.01),while the incidence of three vessel lesion and collateral circulation were much higher than that in group C(P<0.01).In group B,those indexes were not significantly different with other two groups.The incidence of two vessel lesion and complicating left main stem lesion were not significantly different among three groups.⑥In group A, the incidence of readmission(for cardiac reason), recurrent AMI, follow-up and total cardiogenic mortality were higher than that in group C (P<0.01). In group B,those indexes were not significantly different with other two groups(P>0.05).⑦The cumulative death cases who survived initial AMI presented the upward trend among three groups during the period of follow-up.When the follow-up time reached 3rd,4th and 5th years,the cumulative mortality had remarkable statistical discrepancy between group A and group C. The cumulative mortality had no change when the follow-up time reached the 4th and 5th year between group A and group C.In group B,the cumulative mortality was no statistical discrepancy with other two groups.⑧Kaplan-Meier's survival curve showed that the cumulative survival rate of three groups presented downward trend.The survival curve of group A and B declined obviously after four,nine months respectively.The group C's survival curve declined gradually after six months and declined obviously after thirty-six months.Then three survival curve declined mildly.⑨Analyzed by COX's regression, only accepting PCI after first ASTEMI entered COX model, not accepting PCI was an independent prognostic factor of death after first ASTEMI.Conclusions:①In the long-term PA group,the infarct size was smaller than that in the short-term PA group,and the left heart function was superior to the short-term PA group.②The long-term PA could promote the development of collateral circulation and reflected that coronary artery lesion was relatively serious, while collateral circulation had benefit on infarction size and left ventricular function,but it is possible that they hadn't obviously long-term protective effect and couldn't reduce long-term mortality.③In the long-term PA group, the long-term prognosis was relatively worse,the incidence of readmission, recurrent AMI,follow-up and total cardiogenic mortality was higher than that in the short-term PA group.④Accepting PCI was an independent prognostic factor of cumulative survival rate after first ASTEMI,the risk of cardiac death was rising for patients not accepting PCI.⑤To the ASTEMI patients who had the long-term PA history,we should strengthen the third prevention to reduce AMI and major adverse cadiac event in the long run.⑥In the medium-term PA group, there was no significant difference in most indexes with the short and long-term PA group,it didn't exclude from relating to the fact that few cases(only 33) had been accumulated.