血流向量成像技术定量观察主动脉瓣狭窄患者左心室心腔内血流动力学的价值

Value of blood flow vector imaging in quantitative observation of left ventricular hemodynamics in patients with aortic stenosis

目的探讨血流向量成像(VFM)技术观察主动脉瓣狭窄(aortic valve stenosis,AS)患者左心室心腔内血流动力学的价值。方法选取云南省第三人民医院2018年7月~2020年7月收治的166例AS患者为研究对象,所有患者依据主动脉瓣跨瓣压差(MTPG)分为A组[轻度狭窄:MTPG<30 mmHg(1mmHg=0.133kPa),n=62]、B组[中度狭窄:MTPG为(30~50)mmHg,n=55]及C组(重度狭窄:MTPG>50 mmHg,n=49);另外选取我院同期体检健康的166例志愿者为对照组。患者及对照入院后均接受常规心脏超声及VFM图像处理。对比4组常规心脏超声检查指标[左心室射血分数(LVEF)、左心室舒张末期内径(LVEDD)、左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、舒张早期二尖瓣口峰值速度与心房收缩期二尖瓣口峰值速度比值(E/A)];记录并对比4组快速射血期基底段、中间段、心尖段的收缩期峰值流量(Fs)、收缩期负向总流量(SQ)、收缩期峰值流速(Vs)水平;最后采用Pearson相关分析,分析超声检查指标LVEF、E/A与VFM图像处理指标Fs、SQ、Vs的相关性。结果4组LVEDD、LVEDV、LVESV水平对比无显著差异;四组LVEF、E/A对比,对照组>A、B、C组,差异有统计学意义(P<0.01)。4组快速射血期基底段、中间段、心尖段的Fs、SQ、Vs水平对比,对照组>A组>B组>C组,差异有统计学意义(P<0.05)。经相关性分析,超声检查指标LVEF、E/A与快速射血期左心室心腔内的Fs、SQ、Vs呈现出正相关(均P<0.01)。结论AS经VFM检查后能够有效的对患者左心室心腔内血流动力学变化情况进行观察,有利于临床诊疗工作的开展,值得临床医师的关注。

AIM To investigate the value of flow vector imaging(VFM)in observing left ventricular hemodynamics in patients with aortic valve stenosis(AS).METHODS A total of 166 AS patients admitted to our hospital from July 2018 to July 2020 were selected for this study.According to MTPG,the patients were divided into group A(mild stenosis:MTPG<30 mmHg,1 mmHg=0.133 kpa,n=62),group B[moderate stenosis:MTPG(30~50)mmHg,n=55]and group C(severe stenosis:MTPG>50 mmHg,n=49).In addition,166 healthy volunteers in our hospital were selected as control group.Both patients and volunteers received routine echocardiography and VFM image processing after admission.Conventional echocardiographic indicators of the four groups were compared,including left ventricular ejection fraction(LVEF),left ventricular end-diastolic diameter(LVEDD),left ventricular end-diastolic volume(LVEDV),left ventricular end-systolic volume(LVESV)and ratio of peak mitral valve velocity in early diastolic phase to peak mitral valve velocity in atrial systolic phase(E/A).Peak systolic flow rates(Fs),negative total systolic flow rates(SQ)and peak systolic flow rates(Vs)were recorded and compared in the basal segment,middle segment and apex segment during rapid ejection period.Finally,Pearson correlation analysis was used to analyze the correlation between the ultrasonic examination indexes(LVEF,E/A)and VFM image processing indexes(FS,SQ,Vs).RESULTS There was no significant difference in LVEDD,LVEDV and LVESV levels between the four groups.Statistically significant differences were found in LVEF and E/A between the 4 groups(control group>group A,B and C,P<0.01)and statistically significant differences were found in the levels of Fs,SQ and Vs in the basal segment,the middle segment and the apex segment(control group>group A>group B>group C,P<0.05).According to correlation analysis,ultrasound examination indexes LVEF and E/A showed positive correlation with Fs,SQ and Vs in the left ventricle during rapid ejection period(all,P<0.01).CONCLUSION VFM effectively observes the changes of left ventricular hemodynamics in AS patients,which is conducive to the clinical diagnosis and treatment,and is worthy of clinicians’attention.