The Coronary Angiographic Findings In Patients With Minor Myocardial Damage

Objective:To contrast the coronary artery lesions of non-ST-elevation myocardial infarction(NSTEMI) and that of non-minor myocardial damage (non-MMD) , retrospective study the angiographic findings of minor myocardial damage (MMD).we approach the features of coronary artery images of this group patients to guide to discover in time in clinical practice and intensification therapy to them.It is important significance that to avoid the sudden death and great area infarction for these group patients.Method:To select 123 patients with non-ST-elevation acute coronary artery syndrom ,who diagnosed by the first cardiovascular department of shen zhou hospital shen yang medical college from April in 2005 to June in 2007 and consistent with to the coronary heart disease level of WHO。All the patients were checked cTnI(normal value 0～0.1 ng/ml)and CK-MB(normal value 0～25u/l)after hospital admission immediately or in 24 hours .They also experience left and right coronary angiography according to Judkins meathod from several posture projection. According to the different value of cTnI,CK-MB, we divide the selected patients into groups: MMD group: cTnI>0.1 ng/ml ; with normal level of CK-MB; with CK-MB value to heighten and less than two times top limit of normal range ;NSTEMI group:cTnI>0.1 ng/ml,with CK-MB value to heighten and more than two times top limit of normal range ;non-MMD group:cTnI 0～0.1ng/ml,with normal level of CK-MB;to summarize general data and results of coronary angiography of each group,we have studied the angiographic findings in patients with minor myocardial damage by contrast.Result:1. It has no statistics difference among each group in the ratio of male and femal, age, the history of hypertension, the history of diabetes, the history of hypercholesterinemia, fibrinogen whether or not to advance (p>0.05).2. The elevated extent of cTnI value of MMD group is lower than that of the NSTEMI group ,and it has the statistics significance (p<0.01). According to the value of CK-MB,we divide the MMD group into CK-MB normal group and CK-MB slight elevation group,it has no statistics significance between two groups in the values of cTnI (p>0.05).3.Coronary artery pathological changes accumulated points between MMD group and NSTEMI group has no statistics significance(p>0.05),but Coronary artery pathological changes accumulated points of MMD group is higher than that of non-MMD,it has statistics significance(p<0.01);neither normal CK-MB or CK-MB slight elevation,Coronary artery pathological changes accumulated points of MMD group has no statistics significance (p>0.05).4.Coronary angiographic findings of MMD group appear commonly complicated pathological changes: three rami pathological changes; sever pathological changes; near 100% obturation pathological changes; the narrow degree of coronary arteries of near half patients is over 90% in the MMD with CK-MB slight elevation group. It has no statistics significance by contrast to NSTEMI(p>0.05).But non-MMD group appear commonly simple pathological changes:single branch pathological changes; non-obstruction pathological changes. It has statistics significance by contrast to MMD group (p<0.01).5.It has no statistic difference that the level of cTnI of single branch ,double branches, three branches pathological changes in MMD group,in other words the level of cTnI has non obvious correlation with the number of coronary artery (p>0.05);but the level of cTnI in sever narrow group is obviously higher than that of slight narrow group ,in other words the level of cTnI relate to the narrow degree(p<0.05).6.The difference between MMD group and NSTEMI group about the rate of≥50% left main coronary artery (LM) pathological changes,≥70% left anterior descending branch (LAD) pathological changes ,left circumflex branch (LCX) pathological changes ,right coronary artery pathological changes ,diagonal branch pathological changes (D) has no statistics significance,(p>0.05);the affected coronary artery sequence between MMD group and NSTEMI group is similar,that is LAD→D→RCA→LCX→LM;rate of affected LCX,RCA pathological changes in MMD group is obviously higher than that of non-MMD(p<0.05).Discussion:Recently with the appearance of more sensitivity and specific serum biochemical marker and precise image technology,we found that part of unstable angina pectoris (UA) cases with minor myocardial damage show that the level of troponin increase, the value of CK-MB is normal or increase less than two times. Some scholars think that these ischemic MMD patients can be diagnosed acute myocardial infarction by combinding clinic, but another scholars hold a reservation. Now the clinic study on MMD patients is very limit. We can definite MMD patients from non-ST-elevation acute coronary syndrome (NSTE-ACS) patients by checking cTnI, but the extent and persistent time of cTnI elevation is less than that of NSTEMI patients. Now the report about diagnosing quantitation level of cTnI of MMD patient is rare.Once some scholars find troponin of 35% UA patients is positive, their condition suddenly change ,and the danger of prognosis increase compare with ACS patients with troponin non-elevation. Currently to see from coronary angiography, domestic and international research think that the anatomic shape of coronary artery of ACS patients increase, incidence rate of three branches pathological changes and thromboembolism in the coronary artery increase. However,we should further research the feature of the coronary artery of these patients that include narrow degree of criminal blood vessel, pathological changes characteristics of great and small blood vessel and occurrence of the vascular occlusion.This research show that: it has no significant difference in age, sex distribution and history of hypertension, diabetes, hypercholesterinemia and fibrinogen wheather or not to increase,but the result of coronary angiography show that accumulated points of pathological changes of coronary artery of MMD group is significantly higher than that of non-MMD group(p<0.01);it has no statistics difference by contrast NSTEMI group (p>0.05).The features of MMD group is complex: incidence rate of 90%～99% serious narrow pathological changes and three branches pathological changes is higher ,as well occlusion pathological changes existence; the features of MMD group are similar to that of NSTEMI group( p>0.05 ) ,but is obviously different from non-MMD grouop(p<0.05).The level of cTnl in MMD group doesn`t obviously correlated to the numbers of suffered coronary artery(p>0.05),but has correlated to the narrow degree of suffered coronary artery(p<0.05)in MMD group. This finding also show that it has no statistics difference that the rate of pathological changes of suffered LAD,RCA,LCX,D,LM in MMD group compare with that of NSTEMI group(p>0.05),and the sequence of suffered coronary artery is similar to that of NSTEMI group.The suffered coronary artery of MMD group is similar with that of NSTEMI group from coronary angiography.The pathology research of NSTE-ACS show that pathology process:①most frequent reason is non-obstructive thrombus because of atherosclerotic plaque teared to pieces cause coronary artery narrow, platelet aggregation and split plaque fragment cause minute vessels embolism.②Because of certain local intensity fierce spasm of coronary artery or because of the resistance in the small myocardial blood vessel abnormal to shrink;③Coronary artery severe narrow but without spasm or thrombus;④inflammation of the artery cause the plaque become thin and tear to cause coronary artery narrow;⑤Extrinsic source causative factor such as the consume oxygen increase ,coronary artery blood decrease, the supply oxygen reduce etc, lead to the myocardial blood infuse limit. On the base of these pathology mechanism, if cause suffered blood transient clogging or the thrombus material result in the embolism of the small branch of coronary artery, at the same time factors such as collateral circulation and sensitivity of myocardial cell etc, which cause minor myocardial infarction. It include minute focus necrosis (spot necrosis)﹑the small focus necrosis(necrosis area less 10% than that of left ventricle). At this time, the pathological coronary artery changes suddenly. Some sufferers may be quickly make progress into the big area myocardial infarction even sudden death within few day .The prognosis is up to degree of coronary artery pathological changes . If we can identify and interfere in MMD suffers as early as possible and give them anti- ischemic treatment to advert a danger. It is importance meaning to choice treatment strategy for ACS sufferers, so we can revalue non-MMD sufferer after the medicine intervention and patient's condition stabilize and decide further treatment plan. However, the MMD sufferer should be early carried on intervention or surgery treatment. Conclusion:1.The features of MMD group is complex: incidence rate of 90%～99% serious narrow pathological changes and three branches pathological changes is higher, as well occlusion pathological changes existence.2.The level of cTnI doesn`t obviously correlated to the numbers of suffered coronary artery(p>0.05), but has correlated to the narrow degree of suffered coronary artery(p<0.05)in MMD group.3.The angiography of MMD group show that pathological change of LAD,RCA,LCX,D,LM may take place,and the affected coronary artery sequence is:LAD→D→RCA→LCX→LM.