多普勒组织成像技术评价高血压昼夜节律对左室舒张功能的影响

目的应用多普勒组织成像（DTI）技术探讨高血压昼夜节律对左室舒张功能的影响。方法对103例高血压患者进行24h动态血压监测，夜间血压均值较白昼血压均值下降≥10％者确定为杓型组（42例）；夜间血压均值较白昼血压均值下降〈10％者为非杓型组（61例）。同时选取40例健康者为对照组。用DTI记录二尖瓣环侧壁、间隔、前壁和下壁的舒张早期和晚期的峰值运动速度及其比值，计算上述四个位点的均值，分别以Em、Am、Em/Am表示，并用二尖瓣血流多普勒（MPWD）检测舒张期血流速度E峰、A峰及E／A比值以作比较。结果高血压组二尖瓣口血流参数、二尖瓣环DTI参数均明显低于对照组（P〈0．05）；高血压杓型组和非杓型组间E、E／A比值无明显差异（P〉0．05），但非杓型组Em、Em／Am比值明显低于杓型组（P〈0．05）。结论DTI技术能简便、准确定量高血压患者二尖瓣环舒张期运动速度的改变，从而准确判断舒张功能受损的程度，其作用优于传统的MPWD。异常的血压昼夜节律可能提示存在更严重的左室舒张功能损伤。

Evaluation of day-night rhythm of blood pressure effect on left ventricular diastolic function by Doppler tissue imaging

Objective To explore day - night rhythm of blood pressure effect on left ventricular diastolic function in patients with hypertension by Doppler tissue imaging （DTI）. Methods One hundred and three patients with essential hypertension were enrolled in this study. Ambulatory blood pressure monitoring was performed on all the patients. They were divided into two groups according to blood pressure decrease rate in night： 〈 10% into non - dipper group （ n = 61） , ≥ 10% into dipper group （ n = 42） . While 40 normal subjects were as control group. The peak velocity and their ratios in early and late diastolic mitral annulus lateral, septal, anterior, and inferior wall were recorded by DTI, the mean value of the four mitral annular sites were calculated and presented as Em, Am, and Em/Am. Then the mitral blood flow velocity E, diastolic blood flow velocity A, and E/A were examined by mitral blood flow pulsed wave Doppler （MPWD）, and their results were compared. Results The mitral blood parameters and mitral annulus DTI parameters of hypertension group were significant lower than those of contrast group （ P 〈 0.05）. There was no significant difference between the E, E/A of dipper group and those of non - dipper group （ P 〉 0.05）, and the Em, Em/Am of non - dipping group were lower than those of dipping group （ P 〈 0.05）. Conclusion DTI can easily and accurately quantitate the changes of mitral aunular diastolic velocity in patients with hypertension, and also can evaluate the severity of left ventricular diastolic function. This technique is better than MPWD. Abnormal day - night rhythm of blood pressure can indicate the possibility of more severe left ventricular diastolic function damage.