冠状动脉慢血流患者左心室旋转及扭转运动特征与心肌血流灌注的相关性分析

目的应用多巴酚丁胺负荷实时心肌造影超声心动图（RTMCE）结合二维斑点追踪（STE）技术评价冠状动脉慢血流（CSF）患者的心肌血流灌注及左心室旋转、扭转运动特征，并进一步分析二者之间的相关性。 方法选取2017年1月至2019年3月杭州师范大学附属医院因胸痛行冠状动脉造影的患者54例，冠状动脉造影结果为CSF的患者33例为CSF组，结果正常者21例为对照组。应用二维超声测量常规参数，双平面Simpson法获得左心室舒张末容积（LVEDV）及左心室射血分数（LVEF），应用STE技术测量左心室基底水平旋转角度峰值（R_心底）、旋转达峰时间（TPR_心底）和左心室心尖水平旋转角度峰值（R_心尖）、旋转达峰时间（TPR_心尖），并获取左心室扭转角度峰值（LVTW）及旋转延迟时间（RDD）。对所有受试者进行多巴酚丁胺负荷试验，在静息和多巴酚丁胺负荷状态下行RTMCE检查，定量分析得出心肌血容量（A值）、心肌血流速率（β值）、心肌血流量（MBF），并获得心肌血流储备（MFR）。采用Pearson相关分析CSF患者左心室旋转、扭转与心肌血流灌注相关参数之间的相关性。 结果2组受检者LVEDV、LVEF差异均无统计学意义；与对照组比较，CSF组患者R_心尖、LVTW、RDD减小，TPR_心尖增大，差异有统计学意义（U=2.707，t=-2.379、-4.988、2.422；P均<0.05）。与对照组比较，静息时CSF组患者β值减小，差异有统计学意义（t=-2.218，P<0.05）；负荷状态下β值、MBF减小，差异有统计学意义（t=-3.791、-2.612，P均<0.05）；CSF组患者MFR较对照组减小，差异有统计学意义（t=-2.585，P<0.05）。Pearson相关分析表明静息时CSF患者R_心尖、LVTW分别与MBF存在相关性（r=0.502、0.462，P均<0.05）；负荷状态下R_心尖、LVTW分别与MBF存在相关性（r=0.436、0.368，P=0.009、0.035）。 结论CSF患者存在心肌微循环障碍，其R_心尖、LVTW降低，心肌微循环障碍可能是左心室旋转及扭转运动减低的主要决定因素之一。

Characteristics of left ventricular rotation and twist and their correlation with myocardial perfusion in patients with coronary slow flow

ObjectiveTo analyze the changes of myocardial perfusion and the characteristics of left ventricular (LV) rotation and LV twist (LVTW) in patients with coronary slow flow (CSF), and to assess the relationship between them by using dobutamine stress real-time myocardial contrast echocardiography (RTMCE) and speckle tracking echocardiography (STE). MethodsA total of 54 patients who underwent coronary angiography for angina were enrolled at the Affiliated Hospital of Hangzhou Normal University, of whom 33 with CSF were included as a CSF group and 21 with normal coronary angiography findings were included as a control group. After conventional echocardiography, LV end diastolic volume (LVEDV) and LV ejection fraction (LVEF) were measured by the biplane Simpson method. And basal and apical rotation of the LV (R_basal and R_apical) were calculated via Qlab10.4 analysis software offline, the time to basal and apical peak rotation of the LV (TPR_basal and TPR_apical) were calculated through graphics semi-automatically, and LVTW and rotation deformation delay (RDD) were also calculated. RTMCE was performed from the apical 4-, 3-, and 2-chamber views at baseline and after dobutamine stress echocardiography, and parameters including myocardial blood volume (A), myocardial blood velocity (β), myocardial blood flow (MBF), and myocardial flow reserve (MFR) were obtained. The correlation between R_apical/LVTW and MBF/MFR was analyzed. ResultsLVEDV and LVEF had no significant difference between the two groups. Compared with the control group, R_apical, LVTW, and RDD significantly decreased and TPR_apical significantly increased in CSF patients (U=2.707, t=-2.379, t=-4.988, and t=2.422, respectively; P<0.05). At baseline, the value of β in the CSF group was significantly lower than that in the control group (t=-2.218, P<0.05). After dobutamine stress test, patients with CSF showed significantly decreased β, MBF, and MFR (t=-3.791, -2.612, and -2.585, respectively; P<0.05) compared with the control group. Pearson correlation analysis revealed that R_apical and LVTW were correlated with MBF both at rest (r=0.502 and 0.462, respectively; P<0.05) and after dobutamine stress test (r=0.436 and 0.368, respectively; P<0.05). ConclusionBoth R_apical and LVTW are impaired in CSF patients, and coronary microcirculation disorder could be an important contributor to the decrease of left ventricular rotation and twist motion.