Clinical Significance of the Calcification of Coronary Arteries in Patients with Angiographically Normal Coronary Arteries

Abstract

In order to clarify the clinical significance of coronary calcification in pa tients with angiographically normal coronary arteries, exercise electrocardiog raphy was used and left ventricular function was examined noninvasively and invasively. The patient groups were as follows: (1) patients with coronary artery calcification on only the left anterior descending artery but no narrowing lesion on any other arteries (calcified group), (2) patients with a significant stenosis on only the left anterior descending artery (stenotic group), and (3) the control group.

The left ventricular function in the calcified group, as indicated by systolic time intervals and invasive parameters such as ejection fraction and mean sys tolic ejection rate, showed a depression similar to that in the stenotic group, compared with the control group. The incidence of electrocardiographically is chemic responses to exercise testing was significantly higher in the calcified group (75%, p < 0.01) and the stenotic group (68%, p < 0.01) than in the control group (25%). Exercise tolerance time and the maximum double product were markedly smaller in the calcified and the stenotic groups as compared with the control group.

These results indicate that the left ventricular function and coronary reserve in the calcified group were reduced and almost identical with those in the stenotic group. The authors conclude that a calcified coronary artery, even if patent, cannot supply an adequate blood flow for the myocardium, resulting in impaired left ventricular function.