探讨心肌造影超声技术对评价大动脉炎冠状动脉受累患者局部心肌微循环的价值。

选取2017年6月至2019年7月山西省人民医院超声科和太原钢铁（集团）有限公司总医院大动脉炎冠状动脉受累患者15例为大动脉炎冠状动脉受累组，选取同期15名可疑冠状动脉疾病但冠状动脉造影正常的健康人群为对照组。观察大动脉炎冠状动脉受累组冠状动脉狭窄的程度及部位。大动脉炎冠状动脉受累组及对照组均行常规超声心动图检查，采用Simpson法获得左室射血分数。然后，大动脉炎冠状动脉受累组及对照组均行心肌造影超声检查，所测量的心肌血流灌注参数包括灌注开始时间、达峰时间、反映局部心肌血容量的曲线峰值强度A值、反映局部心肌灌注血流速度的曲线斜率β值和局部心肌血流量（A×β值）。使用独立样本t检验比较2组间心肌血流灌注参数的差异。绘制大动脉炎冠状动脉受累心肌灌注参数的受试者工作特征（ROC）曲线，比较各项参数的曲线下面积，确定最佳临界值。

15例大动脉炎冠状动脉受累患者共22处冠状动脉受累并发生狭窄，狭窄率50%~69%者占13.6%（3/22），狭窄率70%~99%者占81.8%（18/22），完全闭塞者1处占4.5%（1/22）。冠状动脉开口处狭窄受累最多86.4%（19/22），少数位于冠状动脉中远段9%（2/22），而且呈节段性改变，仅1处呈单支冠状动脉弥漫性狭窄4.5%（1/22）。15例行冠状动脉造影的患者中单支冠状动脉病变9例（60.0%，9/15），两支冠状动脉病变5例（33.3%，5/15），三支冠状动脉病变1例（6.7%，1/15）。大动脉炎冠状动脉受累组Ａ值［（6.55±1.48）dB vs（8.09±1.35）dB］、β值［（0.45±0.13）/s vs（0.64±0.07）/s］、Ａ×β值［（2.75±1.03）dB/s vs（5.23±0.51）dB/s］均比对照组小，差异均具有统计学意义（t=9.978、15.178、25.260，P均<0.001）。大动脉炎冠状动脉受累组灌注开始时间［（2.74±0.78）s vs（2.55±0.63）s］、达峰时间［（12.43±0.79）s vs（7.53±0.93）］均比对照组延长，差异均具有统计学意义（t=2.059、50.068，P=0.013、<0.001）。大动脉炎冠状动脉受累组左心室射血分数比对照组低，差异具有统计学意义（t=19.969，P<0.001）。A×β值的ROC曲线下面积为0.949，当截断值为4.0017 dB/s时的诊断效能最高，此时敏感度为94.2%，特异度为81.5%。

大动脉炎冠状动脉受累可引起心肌微循环障碍，导致心脏收缩功能受损。心肌造影可准确定量评价大动脉炎冠状动脉受累的患者的心肌血流灌注情况。

To evaluate the role of myocardial contrast echocardiography (MCE) in the assessment of myocardial perfusion in patients with Takayasu arteritis with coronary artery involvement.

Fifteen patients with Takayasu arteritis with coronary artery involvement at Department of Ultrasound of Shanxi Provincial People′s Hospital and Department of Ultrasound of General Hospital of Tisco from June 2017 to July 2019 were selected as a study group, and 15 healthy persons with suspected coronary artery disease but normal coronary angiography were selected as a control group. All of the subjects underwent coronary angiography examination. The degree and location of coronary artery stenosis in the study group were observed based on the results of coronary angiography. The left ventricular ejection fraction (LVEF) was obtained by Simpson′s method. Then, MCE was performed in both groups. The parameters reflecting myocardial microcirculation were measured, including time to start, time to peak, amplitude of peak intensity (A), slope of curve (β), and A×β. The independent sample t-test was used to compare the differences of myocardial perfusion parameters between the two groups. The receiver operating characteristic (ROC) curves were plotted, and the area under the curve (AUC) of each parameter was calculated to determine the optimal critical value.

Twenty-two branches of coronary arteries were involved in the 15 patients with Takayasu arteritis; 13.6% (3/22) of the stenosed coronary artery branches had a stenosis rate of 50%-69%, 81.8% (18/22) had a stenosis rate of 70%-99%, and one was completely occluded, accounting for 4.5% (1/22). Proximal coronary artery stenosis was the most common, with an incidence of 86.4% (19/22). Approximately 9% (2/22) of branches showed segmental changes and were located in the middle or distal segment of the coronary artery. Only one patient presented with a diffuse stenosis of the coronary artery, accounting for 4.5% (1/22). Based on the results of coronary angiography, 60% (9/15) of patients in the study group had a single coronary artery branch involved, 33.3% (5/15) had two coronary artery branches involved, and 6.7% (1/15) had three coronary artery branches involved. The values of A [(6.55±1.48) dB vs (8.09±1.35) dB], β [(0.45±0.13)/s vs (0.64±0.07)/s], and A×β [(2.75±1.03) dB/s vs (5.23±0.51) dB/s] in the study group were significantly lower than those of the control group (t=9.978, 15.178, and 25.260, respectively; P<0.001). Time to start [(2.74±0.78) s vs (2.55±0.63) s] and time to peak [(12.43±0.79) s vs (7.53±0.93) s] were significantly longer in the study group than in the control group (t=2.059, P=0.013; t=50.068, P<0.001). LVEF was significantly lower in the study group than in the control group (t=19.969, P<0.001). With a cut-off value of 4.0017 dB/s, the AUC of A×β was 0.949, with a sensitivity of 94.2% and specificity of 81.5%.

Coronary artery involvement in Takayasu arteritis can cause disturbance of myocardial microcirculation and thus lead to a decrease of cardiac systolic function. MCE can accurately and quantitatively evaluate the myocardial perfusion in patients with Takayasu arteritis with coronary artery involvement.