Craft Mary, Jani Vivek, Bliamptis John, Barnes Benjamin T, Erickson Christopher C, Schuster Andreas, Danford David A, Kutty Shelby
Dr. C.C. and Mabel L. Criss Heart Center, University of Nebraska College of Medicine and Children's Hospital and Medical Center, Omaha, NE, USA.
Helen B. Taussig Heart Center, Department of Pediatrics, Johns Hopkins Hospital, Baltimore, MD 21205-2196, USA.
Int J Cardiol Heart Vasc. 2020 Dec 25;32:100703. doi: 10.1016/j.ijcha.2020.100703. eCollection 2021 Feb.
Vector flow mapping is an emerging echocardiographic method allowing for investigation of intracardiac blood flow mechanics, wall shear stress (WSS), and energy loss (EL). We hypothesized that alterations in EL and WSS will differ among subjects with hypertrophic (HCM), dilated (DCM) cardiomyopathy, and normal controls.
Echocardiograms were prospectively performed with the ProSound F75CV (Hitachi HealthCare., Tokyo, Japan) on all subjects. 2D color Doppler cine loop images were obtained from apical 5 and the apical long axis views and stored digitally. Measurements were averaged over three cardiac cycles using VFM software to derive flow patterns, WSS, and EL. Standard left ventricular (LV) systolic and diastolic functional parameters were also obtained.
A total of 85 subjects, 22 with HCM (age 18 ± 9 yrs.), 18 DCM (age 18 ± 9 yrs.), and 45 age and gender matched controls were included in the study. Diastolic wall shear stress was found significantly different in HCM (0.004 ± 0.185 N/m) compared with DCM (0.397 ± 0.301 N/m, P < 0.001), and controls (0.175 ± 0.255 N/m, P = 0.027). Furthermore, indexed systolic EL was found to be significantly elevated in HCM (13.91 ± 13.17 mW/m/m) compared with DCM (8.17 ± 9.77 mW/m/m, P < 0.001), but not controls (6.45 ± 7.47 mW/m/m).
Differences in abnormal ventricular mechanics observed in HCM and DCM are reflected in both EL and WSS, and are suggestive that changes in energetic parameters may represent novel indices of ventricular dysfunction.
向量血流成像（VFM）是一种新兴的超声心动图方法，可用于研究心腔内血流动力学、壁面切应力（WSS）和能量损失（EL）。我们推测，肥厚型心肌病（HCM）、扩张型心肌病（DCM）患者与正常对照者之间，能量损失和壁面切应力的改变会有所不同。
使用ProSound F75CV（日本东京日立医疗株式会社）对所有受试者进行前瞻性超声心动图检查。从心尖五腔心切面和心尖长轴切面获取二维彩色多普勒电影环图像，并进行数字存储。使用VFM软件在三个心动周期内对测量值进行平均，以得出血流模式、壁面切应力和能量损失。同时还获取了标准的左心室（LV）收缩和舒张功能参数。
本研究共纳入85名受试者，其中22例肥厚型心肌病患者（年龄18±9岁），18例扩张型心肌病患者（年龄18±9岁），以及45例年龄和性别匹配的对照者。与扩张型心肌病患者（0.397±0.301N/m，P<0.001）和对照组（0.175±0.255N/m，P=0.027）相比，肥厚型心肌病患者的舒张期壁面切应力（0.004±0.185N/m）显著不同。此外，与扩张型心肌病患者（8.17±9.77mW/m/m，P<0.001）相比，肥厚型心肌病患者的标准化收缩期能量损失显著升高（13.91±13.17mW/m/m），但与对照组（6.45±7.47mW/m/m）相比无显著差异。
肥厚型心肌病和扩张型心肌病中观察到的异常心室力学差异反映在能量损失和壁面切应力上，提示能量参数的变化可能代表心室功能障碍的新指标。
