Comparison and Analysis of Acute Myocardial Infarction with or Without Angiographical Normal Coronary Artery

Objective To compare the clinical characteristics between acute myocardial infarction(AMI)patients with angiographically normal coronary artery and those with angiographically coronary stenosis. Methods 399 consecutive AMI patients underwent selective coronary angiography after hospitalization. The characteristics of CAD risk factors and left ventricular function were compared between the group with angiographically normal coronary artery and the group with angiographically coronary stenosis. Results 94.24%(376/399) cases showed angiographically coronary stenosis: 307 cases of them with coronary stenosis equal to or more than 90%. 5.76%(23/399) cases showed angiographically normal coronary artery: 7 cases with 0% coronary artery diameter stenosis, 16 cases with 10%～40% stenosis. The results compared between the group with normal coronary artery and the group with coronary stenosis were as follows: the percentage of people younger than 40 was 26.08%(6/23) vs 6.12% (23/376)(P0.05); the percentage of women was 43.48%(10/23) vs 18.88%(71/376)(P0.05). The percentage of diabetes, hyperlipemia and hypertension was 26.08%(6/23)vs 15.69%(59/376),73.91%(17/23) vs 67.82%(255/376),26.08%(6/23) vs 28.48%(107/376) respectively(P0.05); There was no statistical difference in terms of the number of risk factor(P0.05); Left ventricular end diastolic pressure(LVEDP) was 12.53 mmHg±5.46 mmHg vs 18.75 mmHg±7.10 mmHg(P0.01). Left ventricular ejection fraction(LVEF)was 63.56%±8.18% vs 59.56%±12.04%(P0.05). Conclusion AMI with angiographically normal coronary artery is not a rare phenomenon, and the mechanism is predominantly related to the dissolution of thrombus, which is usually caused by coronary spasm or rupture of tiny atherosclerotic coronary plagues. Compared with the group with coronary stenosis, the group with angiographically normal coronary artery features a better left ventricular function, more young people and more women, and shares the same proportion of diabetes, hyperlipemia and hypertension.