RT Journal Article SR Electronic T1 The impact of overweight and obesity on Chinese coronary microvascular function by using quantitative 13N-ammonia PET/CT JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 651 OP 651 VO 61 IS supplement 1 A1 Wang, Ruonan A1 Wu, Zhifang A1 Wu, Ping A1 LI, Li A1 Li, Sijin YR 2020 UL http://jnm.snmjournals.org/content/61/supplement_1/651.abstract AB 651Objectives: Obesity is associated with structural and functional changes in the heart increasing cardiovascular risk. This study aimed to investigate coronary microvascular function with overweight and obese patients without obstructive coronary artery disease. Methods: A total of 165 consecutive patients without obstructive coronary artery disease underwent quantitative 13N-ammonia positron emission tomography (PET)/CT. Baseline demographics, hemodynamic parameters, myocardial blood flow (MBF), coronary flow reserve (CRF), and coronary microvascular resistance (CMVR) were recorded for each subject. Study participants (n = 165) were divided into three groups based on their body mass index (BMI, kg/m2 ): Group 1, patients with BMI 18.5-23.9 (n = 56, normal weight); Group 2, patients with BMI 24.0-27.9 (n = 67, overweight) and Group 3, patients with BMI ≥28.0 (n = 42, obese). Results: Resting MBF was comparable between normal-weight and overweight groups, but significantly lower in obese group (1.08 ± 0.26 ml/min/g in Group 1, 1.03 ± 0.30 ml/min/g in Group 2 and 0.92 ± 0.20 ml/min/g in Group 3, P < 0.05). When adjusted for RPP, there are significantly lower NMBF in the overweight and obese groups compared with normal-weight subjects (1.36 ± 0.34ml/min/g in Group 1, 1.16 ± 0.38 ml/min/g in Group 2 and 1.07 ± 0.27 ml/min/g in Group 3, p < 0.05). The hyperaemic MBF was significantly lower in the overweight and obese groups compared with the control-weight group (3.53 ± 1.05 ml/min/g in Group 1, 3.09 ± 0.96 ml/min/g in Group 2 and 2.90 ± 0.97 ml/min/g in Group 3, p < 0.05). The CFR have no significant different between the 3 groups (p > 0.05). Compared with control-weight group, CMVR was significantly higher in overweight and obese groups (25.34 ± 9.57 mm Hg/ml/min/g in Group 1; 30.10 ± 9.89 mm Hg/ml/min/g in Group 2 and 33.69 ± 13.06 mm Hg/ml/min/g in Group 3, p < 0.05). BMI was independently associated with hyperaemic MBF and CMVR. Conclusions: Our study demonstrates that Chinese overweight and obese patients without obstructive coronary heart disease are at risk of coronary microvascular dysfunction and the BMI is independent risk factor of coronary microvascular dysfunction.