Study on the relationship between QT dispersion and the severity of coronary artery disease.

Objective To explore the relationship between the severity and stenosis of coronary artery stenosis and QT dispersion(QTd) and corrected QT dispersion(QTcd), and explore its clinical significance in patients with coronary heart disease.Methods Sixty-four patients underwent conorary angiography(CAG).Eighteen patients who were proved to be coronary artery disease(CAD) with coronary artery stenosis ranging from 50% to 70% were enrolled in the moderate stenosis group. Twenty patients whose stenosis 70% were enrolled in the severe stenosis group.Sixteen patients who were proved to be CAD with one-vessel stenosis were enrolled in the one-vessel stenosis group.Twenty-two patients were enrolled in the over two-vessel group.Twenty-six patients who were proved not to be CAD with stenosis 50% by conorary angiography were enrolled in the control group. Results The effectiveness on QTd and QTcd was significant in the severe stenosis group(P0.005),but not significant in the moderate stenosis group(P0.05).The effectiveness on QTd and QTcd was significant in the over two-vessel group (P0.05),but not significant in the one-vessel stenosis group(P0.05). Conclusion The severity and stenosis of coronary artery had a relation with QTd and QTcd . More severe the myocardium ischemia and injury were , more obvious the QTd and QTcd extension will be,which maybe a significant index for evaluating the severity of myocardium ischemia and injury in patients with coronary heart disease.