[Value of absolute quantification of myocardial perfusion by PET in detecting coronary microvascular disease in patients with non-obstructive coronaries].

Objective: To compare the incidence of coronary microvascular disease (CMVD) between patients with non-obstructive and obstructive coronary arteries. Methods: We retrospectively analyzed 97 patients with angina pectoris, who underwent the absolute quantitative PET examination of myocardial perfusion and coronary anatomy examination within 90 days. All patients were divided into two groups: non-obstructive group (72 cases, no stenosis ≥50% in all three coronary arteries) and obstructive group (25 cases, at least one coronary stenosis ≥50%; and at least one coronary stenosis<50%). Quantitative parameters derived from PET including rest myocardial blood flow (RMBF), stress myocardial blood flow (SMBF), coronary flow reserve (CFR) and cardiovascular risk factors were compared between the two groups. CMVD was defined as CFR<2.90 and SMBF<2.17 ml·min(-1)·g(-1). Results: Incidence of CMVD was significant higher in the non-obstructive coronary arteries of the obstructive group than in the non-obstructive coronary arteries of non-obstructive group (47.1% (16/34) vs. 25.5% (55/216), χ(2)=6.738, P=0.009) while incidence of CMVD was similar between non-obstructive and obstructive patients ((44% (11/25) vs. 33.3% (24/72), χ(2)=0.915, P=0.339). RMBF ((0.83±0.14) ml·min(-1)·g(-1) vs. (0.82±0.17) ml·min(-1)·g(-1)), SMBF ((2.13±0.60) ml·min(-1)·g(-1) vs. (1.91±0.50) ml·min(-1)·g(-1)) and CFR (2.59±0.66 vs. 2.36±0.47) were similar between the two groups (all P>0.05). Conclusions: CMVD can occur in non-obstructive coronary arteries in both patients with non-occlusive coronary arteries and patients with obstructive coronary arteries. Prevalence of CMVD is significantly higher in patients with obstructive coronary arteries than in patients with non-obstructive coronary arteries. The CMVD severity is similar between the two groups.目的： 比较非阻塞及阻塞性冠状动脉（冠脉）疾病患者的冠脉微血管疾病（CMVD）发生情况。 方法： 回顾性分析2015年12月至2019年12月在山西医科大学附属第一医院成功完成(13)N-氨水正电子发射计算机断层显像（PET）心肌血流绝对定量检查并在PET检查90 d内完成冠脉造影或CTA的97例疑诊CMVD患者，根据造影及CTA结果将患者分为非阻塞组（72例，3支冠脉均不存在狭窄≥50%的病变）和阻塞组（25例，至少存在1支冠脉狭窄≥50%，且至少存在1支冠脉狭窄<50%），以冠脉血流储备（CFR）<2.90且负荷心肌血流量（SMBF）<2.17 ml·min(-1)·g(-1)为CMVD的判定标准，从血管及患者层面分析两组患者非阻塞性冠脉的CMVD发生情况，并比较两组间发生CMVD的冠脉支配区的静息心肌血流量（RMBF）、SMBF及CFR。 结果： 在血管层面，阻塞组非阻塞性冠脉存在CMVD的比例高于非阻塞组[47.1%（16/34）比25.5%（55/216），χ(2)=6.738，P=0.009]。在患者层面，两组发生CMVD的比例差异无统计学意义[（44%（11/25）比33.3%（24/72），χ(2)=0.915，P=0.339]。两组间发生CMVD的冠脉支配区的RMBF[（0.83±0.14）ml·min(-1)·g(-1)比（0.82±0.17）ml·min(-1)·g(-1)]、SMBF[（2.13±0.60）ml·min(-1)·g(-1)比（1.91±0.50）ml·min(-1)·g(-1)]及CFR（2.59±0.66比2.36±0.47）比较，差异均无统计学意义（P>0.05）。 结论： 非阻塞与阻塞性冠脉疾病患者的非阻塞性冠脉均可存在CMVD，后者的CMVD检出率更高，两者CMVD的严重程度基本一致。.