PET心肌血流绝对定量对冠状动脉微血管疾病的诊断价值

The value of PET quantitative analysis of coronary physiology in the diagnosis of coronary microvas- cular disease

目的应用静息和负荷13N-NH3 PET心肌灌注显像（MPI）对心肌血流及储备功能进行绝对定量，以评估PET对冠状动脉微血管疾病（CMVD）的诊断价值，并为准确分型提供依据。方法前瞻性纳入2016年7月至2017年9月间23例（男16例，女7例，年龄27～70岁）临床疑诊CMVD的患者，行一日法静息＋ATP负荷13N-NH3 PET MPI，使用Heartsee软件分析图像，获得心肌血流相对摄取值、绝对定量值（MBF）和冠状动脉血流储备（CFR）值。根据所获得的信息诊断或排除CMVD。结合心肌酶谱检查、心脏彩超、MRI、冠状动脉造影、CT血管成像（CTA）等结果，将确诊的CMVD患者分为不合并（1型）或合并阻塞性冠状动脉疾病型（2型）及其他类型（3型）。采用两样本t检验、单因素方差分析等分析数据。结果23例中17例确诊为CMVD（其中1型10例，2型3例，3型4例），6例排除了CMVD。CMVD组与非CMVD组患者的年龄、性别、危险因素差异均无统计学意义（均P〉0.05）；相对摄取数据中静息、负荷左室整体平均摄取值、负荷〈60%最大摄取值占左室面积的百分比组间差异有统计学意义（t值：－3.249～2.469，均P〈0.05）；所有绝对血流定量指标（包括静息及负荷状态左室整体MBF、CFR，以及最小象限MBF、CFR）组间差异均有统计学意义（t值：－8.278～－3.258，均P〈0.05）。3种类型的CMVD患者的相对摄取数据组间差异无统计学意义（F值：0.002～1.440，均P〉0.05）。绝对血流定量数据中静息、负荷左室整体MBF平均值、最小象限平均值组间差异均有统计学意义（F值：3.885～8.452，均P〈0.05）。结论PET心肌血流绝对定量可为CMVD的诊断和准确分型提供一种无创、安全、准确的检查方法。

ObjectiveTo evaluate the diagnostic value of quantitative rest and stress 13N-NH3 PET myocardial perfusion imaging （MPI） on coronary microvascular disease （CMVD）, and provide basis for accurate classification.MethodsFrom July 2016 to September 2017, a total of 23 patients （16 males, 7 females; 27-70 years） who were suspected of CMVD were prospectively enrolled in this study. Rest and ATP-stress MPI were acquired using 13N-NH3 PET and analyzed using Heartsee software. Rest and stress relative uptake, absolute myocardial blood flow （MBF） and coronary flow reserve （CFR） were obtained and present on sectional images and cup maps. Based on the information, CMVD was diagnosed or excluded. Combined with myocardial enzymes, echocardiography, cardiac MRI, coronary angiography, CT angiography （CTA）, CMVD was further divided into CMVD without （type 1） or with obstructive coronary disease （type 2）, and other CMVD （type 3）. Two-sample t test and one-way analysis of variance were used to analyze the data.ResultsIn 23 patients, 17 cases were diagnosed as CMVD （including 10 cases with type 1, 3 cases with type 2 and 4 cases with type 3）, and 6 cases were excluded. There were no significant differences in the age, gender and risk factors between CMVD group and exclusion group （all P〉0.05）. The relative uptake results, including average uptake of whole left ventricle in rest and stress states, rest minimum quadrant, and area of stress uptake less than 60% of maximum were significantly different between the two groups （t values： from -3.249 to 2.469, all P〈0.05）. All the absolute blood flow parameters, including rest and stress whole MBF and CFR, rest and stress minimum quadrant MBF and CFR, were significantly different between CMVD group and exclusion group （t values： from -8.278 to -3.258, all P〈0.05）. There was no statistically significant difference for relative uptake data among three types of CMVD （F values： from 0.002 to 1.440, all P〉0.05）. For absolute quantitative values of whole MBF and minimum quadrant MBF in both rest and stress states, difference was statistically significant among groups （F values： from 3.885 to 8.452, all P〈0.05）.ConclusionQuantitative PET MPI could provide a noninvasive, safe and accurate method for the diagnosis and classification of CMVD.