超声血流向量成像技术评价2型糖尿病患者左心室舒张期能量损耗

目的应用超声血流向量成像（VFM）技术评价2型糖尿病（D2M）患者舒张期左心室心腔血液流场状态，探讨左心室能量损耗（EL）定量评价D2M患者左心室舒张功能障碍的应用价值。 方法选取2014年12月至2015年5月四川省人民医院收治的D2M患者62例（D2M组）及同期健康体检者39名（健康对照组）。采集2组受检者常规二维超声图像及3个完整心动周期动态标准心尖三腔（AP3c）彩色多普勒血流图，测量左心室常规径线及舒张功能参数。将AP3c彩色多普勒动态图导入图像后处理工作站，获取舒张期左心室心腔EL参数和时间流量曲线（T-F curve）；根据T-F curve将舒张期分为等容舒张期（P1）、舒张早期（P2）、快速充盈期（P3）、减慢充盈期（P4）、心房收缩期（P5）、舒张末期（P6）6期。记录每一时相EL值（Pn-EL，n=1~6）。采用Wilcoxon秩和检验比较2组受检者舒张期各时相EL参数差异。采用Spearman相关分析分析2组受检者EL与左心室舒张功能参数的相关性。 结果D2M组患者P1-EL、P2-EL、P3-EL、P4-EL、P5-EL、P6-EL分别为5.233、4.328、17.249、9.043、13.829、9.765 N/（m ? s），健康对照组受检者P1-EL、P2-EL、P3-EL、P4-EL、P5-EL、P6-EL分别为3.191、2.587、16.025、6.324、8.858、8.093 N/（m ? s）。D2M组患者舒张期P1-EL、P2-EL、P4-EL、P5-EL、P6-EL均高于健康对照组受检者，且差异均有统计学意义（Z值分别为-3.042、-2.386、-2.103、-2.763、-2.107，P均<0.05或0.01）；D2M组患者舒张期P3-EL也高于健康对照组受检者，但差异无统计学意义。D2M组患者P3-EL与E、E/A均呈显著正相关（r=0.741、0.599，P均<0.01），与e、E/e均呈正相关（r=0.3、0.253，P均<0.05）；P5-EL与A、a值均呈显著正相关（r=0.578、0.384，P均<0.01），而与E/A、e/a均呈显著负相关（r=-0.427、-0.537，P均<0.01）。健康对照组受检者P3-EL与E呈显著正相关（r=0.732，P<0.01)，与E/A、e均呈正相关（r=0.4、0.321，P均<0.05）；P5-EL与A、a均呈正相关（r=0.688、0.399，P均<0.05），与E/A呈负相关（r=-0.406，P<0.05）。 结论D2M患者舒张期部分时相左心室EL增高，有望成为定量评价左心室舒张功能障碍的指标之一。特定时相左心室EL与左心室血流动力学状态相关。

Left ventricular energy loss in patients with 2 type diabetes during diastole detected by ultrasonic vector flow mapping

ObjectiveTo quantitatively evaluate left intraventricular blood flow patterns and explore the value of energy loss (EL) of left ventricle in patients with type 2 diabetes mellitus (D2M) for diastolic dysfunction using ultrasonic vector flow mapping. MethodsRandomly selected 62 patients with D2M as case group and 39 normal adults for control group. Acquired 2D gray-scale echocardiographic images and standard dynamic apical 3 chambers (AP3c) Doppler flow images for 3 completed cardiac cycles for the measurement of general parameters of left ventricular structure and diastolic function. The AP3c Doppler flow dynamic images were analyzed using off-line workstation for acquiring the EL parameters and time-flow curve (T-F curve) of left ventricular inflow tract during diastole. Diastole of left ventricle was divided into the isovolumic relaxation phase (P1), early diastolic phase (P2), rapid filling phase (P3), slow filling phase (P4), atria contract period (P5) and late diastolic phase (P6) based on T-F curve, with recording EL of each phase (Pn-EL, n=1-6). The difference of general parameters and EL value and the correlation between EL and diastolic hemodynamic parameters of above 2 groups were analyzed. Results(1) EL: The value of P1-EL, P2-EL, P3-EL, P4-EL, P5-EL, P6-EL were dividedly 5.233, 4.328, 17.249, 9.043, 13.829, 9.765 N/(m?s) in D2M group, and were dividedly 3.191, 2.587, 16.025, 6.324, 8.858, 8.093 N/(m?s) in normal group; Compared between D2M group and normal group, the EL of all periods were higher with statistical significance in P1, P2, P4, P5, P6 phases (Z=-3.042, -2.386, -2.103, -2.763, -2.107, all P<0.01 or 0.05). (2) Correlation analysis: In D2M group, a significant positive correlation existed between P3-EL and E, E/A (r=0.741, 0.599, both P<0.01), and there were positive correlations between P3-EL and e, E/e (r=0.3, 0.253, both P<0.05); There was a significant positive correlation between P5-EL and A, a (r=0.578, 0.384, both P<0.01), and significant negative correlations between P5-EL and E/A, e/a (r=-0.427, 0.537, both P<0.01). In normal group, there were a significant positive correlation between P3-EL and E (r=0.732, P<0.01) and positive correlations between P3-EL and E/A, e (r=0.4, 0.321, both P<0.05); There were a positive correlation between P5-EL and A, a (r=0.688, 0.399, both P<0.05), and negative correlation between P5-EL and E/A (r=-0.406, P<0.05). ConclusionThe higher diastolic EL of left ventricle in patients with D2M during most phases of diastole indicate that EL might be used as a quantitative index for evaluating the left ventricular diastolic dysfunction, and there is a close correlation between EL parameters and left ventricular hemodynamics in specific phases of diastole.