Comparative study of the right coronary artery and left circumflex artery occlusion

Objective:To analyse the electrocardiography(ECG) characteristic,heart function,and prognosis of acute inferior infarction cuased by occlusion of right coronary artery(RCA) or left circumflex artery(LCX).Method:Ninety patients with first acute inferior infarction confirmed by coronary angiography(CAG) were divided into two groups: RCA occlusion group(n=63),LCX occlusion group(n=27).All patients underwent direct percutaneous coronary intervention(PCI) within 24 h after onset of AMI.~(99m)Tc-MIBI SPECT was performed to detect myocardial infarction area and ~(99m)Tc gated cardiac blood pool image was performed to detect left ventricular ejection fraction(LVEF) at 2 weeks after PCI.The incidence of arrhythmia,heart failure,cardiogenic shock and mortality was observed.Result:①The incidence of inferior infarction combined with right ventricular infarction was significantly higher and the incidence of inferior infarction combined with lateral infarction was lower in RCA group than that in LCX group(P0.01).② The incidence of IIIst↑II st↑ and aVL st↓I st↓was significantly higher in RCA group than that in LCX group(P0.01).③The peak creatine MB fraction was higher and myocardial infarction area was larger in group RCA than those in group LCX(P0.05).④LVEF was lower in RCA group than that in LCX group(P0.05).⑤There was a trend of higher incidence of arrhythmia,heart failure,cardiogenic shock and mortality in group RCA compared with that in group LCX.Conclusion:Myocardial infarction area was larger and heart function and prognosis were poorer in RCA occlusion than those in LCX occlusion.