Sex-dependent association between coronary vessel dominance and cardiac syndrome X: a case-control study

BACKGROUND Previous studies have demonstrated the relevance of left coronary artery dominance in the outcome and prognosis of obstructive coronary artery disease (CAD). However, no studies have investigated the influence of coronary vessel dominance on non obstructive CAD. The aim of this study was to establish the association of left and mixed dominance of the major epicardial arteries with the development of non obstructive CAD and evaluate potential sex-dependent differences in the coronary artery supply. METHODS A total of 484 patients underwent the same diagnostic procedures. The patients were divided into two groups based on their coronary angiogram results: the control group (242 patients with obstructive CAD; coronary artery stenosis of ≥50%) and the experimental group (242 patients with non obstructive CAD; coronary artery stenosis of <50%). RESULTS Significantly more women than men were affected by non obstructive CAD (P = 0.005). Left dominance was more frequent in the non obstructive CAD group than in the control group (P = 0.018) and was more pronounced in women than in men (P = 0.013). Among men with non obstructive CAD, a left supply was more frequent than a mixed supply (P = 0.012). Women with non obstructive CAD had a higher frequency of a left supply, whereas a mixed supply was less frequent in men than in patients with obstructive CAD (P = 0.013 and 0.018, respectively). CONCLUSION These results suggest that left dominance (particularly in women) and the absence of a mixed supply in men could cause regional ischemia, thus affecting the development of non obstructive CAD. Furthermore, sex may determine the incidence of specific coronary artery supply types, therefore influencing disease development and prognosis.