Relationship between severity of coronary artery lesions and cardiac function

AIM: To investigate the relationship between the scope and degree of coronary artery stenosis and the function of the heart. METHODS: We studied 387 patients who underwent selective coronary arteriography (CAG). The 252 patients who had been diagnosed as having coronary heart disease (CAD) by CAG were divided into different groups according to the extent of the lesion and the stenosis of the artery. All patients were examined by heart ultrasonography before CAG. On the basis of the CAG and heart ultrasonography results, we analyzed the correlation between the scope and degree of coronary artery stenosis and the function of the heart. RESULTS: In the patients with low- to medium-grade stenosis or with one stenosed coronary artery, only the diastolic function of the left ventricle decreased (P<0.05 or P<0.01). In patients with high-grade stenosis and total occlusion, both the diastolic and systolic function of the left ventricle decreased and the decreased degree of contractile function had a significant correlation with the number and severity of involved coronary arteries (P<0.01). CONCLUSION: The severity of coronary stenosis influences the function of the heart. In patients with CAD, the diastolic function of the heart decreases before the systolic function.