LAUSR

Background To investigate the effect and possible mechanism of obstructive sleep apnea hypopnea syndrome on coronary microcirculation in stable angina pectoris (SAP) patients with a single borderline lesion. Methods We retrospectively analyzed 102 SAP patients with a single critical lesion [fractional flow reserve > 0.80] who were divided into an abnormal microcirculatory function group [index of microcirculatory resistance (IMR) ≥ 25, n = 52] and normal microcirculatory function (NMF) group (IMR < 25, n = 50). We compared indexes including biochemical indicators, coronary lesion characteristics, apnea hypopnea index (AHI), lowest oxygen saturation (LSaO2), night average heart rate, endothelin-1 (ET-1), nitric oxide (NO) and high-sensitivity C-reactive protein in serum between the two groups. Furthermore, risk factors affecting coronary microcirculation were analyzed. Results There were no significant differences in biochemical indexes and coronary lesion characteristics between the two groups (p > 0.05). Compared to the NMF group, AHI (23.76 ± 8.41 times/h) and ET-1 (1.96 ± 0.43 ng/L) were obviously increased (p < 0.01), and LSaO2 (77.96 ± 7.26%) and NO (23.63 ± 7.09 μmol/L) was significantly lower in the AMF group (p < 0.01). Moreover, AHI and ET-1 were positively associated with IMR (r1 = 0.887, 0.835, respectively). However, LSaO2 and NO had a negative correlation with IMR (r3 = 0.659, 0.691, respectively). Logistic regression analysis showed that AHI was an independent predictor of coronary microcirculatory dysfunction (odds ratio = 1.260, 95% confidence interval 1.083~1.467, p < 0.01). Receiver operating characteristic (ROC) curve analysis indicated an AHI cut-off value of 13.7 times/h to predict microcirculatory dysfunction (sensitivity 0.942, specificity 0.880). Conclusions In SAP patients with a single critical lesion, AHI was associated with coronary microcirculatory dysfunction.