Slow coronary flow is associated with carotid artery dilatation.

Slow coronary flow (SCF) in a normal coronary angiogram is a well-recognized clinical entity, but its etiopathogenesis remains unclear. Carotid intima-media thickness (CIMT) is a noninvasive marker of atherosclerosis. The aim of this study was to investigate the CIMT and diameter of carotid and coronary artery in relation to SCF. Twenty-four patients with angiographically diagnosed SCF (51 +/- 7 years), and 26 age-matched subjects with normal coronary flow (NCF) (52 +/- 8 years) in the coronary angiography were enrolled. Coronary flow rates were documented by thrombolysis in myocardial infarction (TIMI) frame count (TFC), a simple method for evaluating coronary blood flow. Carotid and coronary artery diameters and CIMT were measured. Mean TFC was significantly higher in patients with SCF than in patients with NCF (p < 0.001). There were no significant differences regarding maximum (p = 0.84) and mean CIMT (p = 0.61). On the other hand, carotid lumen (p = 0.03) and coronary artery diameters (p = 0.001) were significantly greater in patients with SCF than in subjects with NCF. There was a significant relation between mean coronary artery diameter and TFC (p = 0.004, 95% CI for OR: 1.61-11.87). In conclusion, these findings suggest that CIMT is not altered in patients with SCF as compared with those with NCF. However, carotid and coronary artery diameters are increased in patients with SCF as compared to those with NCF. Because the common carotid artery can be assessed in nearly every patient, carotid artery dilatation may be used as an early indicator for SCF.