Coronary blood flow in patients with cardiac syndrome X.

Background: Epicardial coronary arteries are normal in patients with cardiac syndrome X. It is, however, unclear whether there is an abnormality at the level of microvascular circulation. In this study, our aim was to evaluate the epicardial coronary blood flow and myocardial perfusion in patients with cardiac syndrome X.

Methods: Two hundred and three patients (mean age 53+/-10 years, 85 men) were included in the study. The diagnosis of cardiac syndrome X was made in patients who had a complaint of typical anginal chest pain and had ischemic findings on either myocardial perfusion scintigraphy or a treadmill exercise test, and whose coronary angiograms did not reveal any pathology. Fifty patients (mean age 54+/-11 years, 24 men) who had a complaint of typical anginal chest pain and had a normal myocardial perfusion test and normal coronary arteries were recruited as the control group. Epicardial coronary blood flow was evaluated with the thrombolysis in myocardial infarction frame count method and myocardial perfusion was evaluated with the myocardial blush grade method. A myocardial blush grade of < or =2 in any vessel was considered abnormal.

Results: Although the right coronary thrombolysis in myocardial infarction frame count was higher in patients with syndrome X (14.9+/-7.6 vs. 11.7+/-4.4 in controls; P=0.014), there were no statistically significant differences between the groups in terms of mean thrombolysis in myocardial infarction frame count in the coronary arteries. Abnormal myocardial blush grade was present in 85 patients (42.3%) with syndrome X, and in 17 patients (34.7%) in the control group (P>0.05).

Conclusion: We found that the epicardial coronary blood flow, as assessed by thrombolysis in myocardial infarction frame count, and myocardial perfusion, as assessed by myocardial blush grade, were normal in patients with cardiac syndrome X.