Effects of Insulin Resistance on Myocardial Blood Flow and Arterial Peripheral Circulation in Patients with Polycystic Ovary Syndrome

Objective Polycystic ovary syndrome ( PCOS ) is associated with increased risk for cardiovascular disease. We sought to evaluate the effects of insulin resistance ( IR ) on myocardial microcirculation and peripheral artery function in patients with PCOS . Methods We studied 55 women (28 with PCOS without IR , 18 with PCOS and IR and 11 normal controls) who underwent laboratorial analysis, high‐resolution vascular ultrasound and real time myocardial contrast echocardiography ( RTMCE ). Intima–media thickness ( IMT ) and brachial artery flow‐mediated dilation ( FMD ) were evaluated by vascular ultrasound. The replenishment velocity (β), plateau of acoustic intensity (A) and myocardial blood flow reserve ( MBFR ) were determined by quantitative dipyridamole stress RTMCE . Results β reserve in group PCOS  +  IR was lower than control (2.34 ± 0.55 vs. 3.60 ± 0.6; P < 0.001) and than PCOS without IR (2.34 ± 0.55 vs. 3.17 ± 0.65; P < 0.001). MBFR in patients with PCOS without IR did not differ from those of control (4.59 ± 1.59 vs. 5.30 ± 1.64; P = 0.22) or from patients with PCOS  +  IR (4.59 ± 1.59 vs. 3.70 ± 1.47; P = 0.07). When comparing with control group, patients with PCOS  +  IR had lower MBFR (5.30 ± 1.64 vs. 3.70 ± 1.47; P = 0.01). No significant differences were found between control, PCOS without IR and PCOS  +  IR for FMD (0.18 ± 0.05, 0.15 ± 0.04 and 0.13 ± 0.07; P = NS ) or IMT (0.48 ± 0.05, 0.47 ± 0.05 and 0.49 ± 0.07; P =  NS ). Conclusion Women with PCOS and IR had depressed β and MBFR as demonstrated by quantitative RTMCE , but no alteration in endothelial dysfunction or IMT . PCOS without IR showed isolated depression in β reserve, probably an earlier marker of myocardial flow abnormality.