Henk C B, Schlechta B, Grampp S, Gomischek G, Klepetko W, Mostbeck G H
Department of Radiology, Ludwig Boltzmann Institute for Physical and Radiological Tumor Diagnosis, University of Vienna, Austria.
Chest. 1998 Sep;114(3):771-9. doi: 10.1378/chest.114.3.771.
It is the purpose of this study to compare pulmonary and aortic blood flow measurements obtained in patients after single lung transplantation (SLTX) with those in volunteers. METHODS/MATERIAL: In nine patients after SLTX (three male, six female) and nine volunteers (seven male, two female), double oblique phase contrast cine-MRI sequences perpendicular to the direction of blood flow were obtained in the ascending aorta, main, right, and left pulmonary artery on a 0.5-T unit (Philips Gyroscan; Best, the Netherlands) (repetition time, 600 to 800 ms; echo time, 8 ms; alpha=30; field of view=280 mm matrix, 128x256, ECG gating, temporal resolution 16 time frames/RR interval). An initial in vitro study using the same sequence on a nonpulsatile flow phantom showed excellent correlation (r=0.99) between MRI measurements of flow velocity and flow volume and true velocity and flow volume. Measurements of blood flow volume (mL/min), peak mean systolic velocity, resistive index, and distensibility index were obtained in each vessel.
We found excellent correlations between left and right cardiac output as measured by velocity encoded cine-MRI (VEC-MRI) in the ascending aorta and main pulmonary artery both in normal volunteers (r=0.95) and in patients (r=0.91). Differential pulmonary blood flow measurements in volunteers showed that 55% of the right cardiac output was directed to the right and 45% to the left lung. Differential pulmonary blood flow in patients showed that most of the blood flow (81%) reaches the transplanted lung and only 19% reaches the patient's own lung (SLTX: 4.5+/-1.8 L/min, patient's own lung: 1.2+/-0.8 L/min). There were significant differences (p<0.05) in peak mean systolic velocity and resistive index obtained in the pulmonary arteries, both between normal volunteers and patients and between measurements obtained in the patient's own lung and the transplanted lung.
VEC-MRI blood flow measurements are a promising noninvasive tool to monitor the hemodynamic changes of pulmonary blood flow after SLTX.
本研究旨在比较单肺移植（SLTX）患者与志愿者的肺血流和主动脉血流测量结果。方法/材料：选取9例SLTX术后患者（3例男性，6例女性）和9名志愿者（7例男性，2例女性），在0.5-T设备（飞利浦Gyroscan；荷兰贝斯特）上，于升主动脉、主肺动脉、右肺动脉和左肺动脉获取垂直于血流方向的双斜位相位对比电影磁共振成像（cine-MRI）序列（重复时间600至800毫秒；回波时间8毫秒；α = 30；视野 = 280毫米矩阵，128×256，心电图门控，时间分辨率16个时间帧/RR间期）。一项在非搏动性血流模型上使用相同序列的初步体外研究显示，MRI测量的流速和流量与真实流速和流量之间具有极佳的相关性（r = 0.99）。获取各血管的血流量（毫升/分钟）、收缩期峰值平均速度、阻力指数和扩张性指数测量值。
我们发现，在正常志愿者（r = 0.95）和患者（r = 0.91）中，通过升主动脉和主肺动脉的速度编码电影磁共振成像（VEC-MRI）测量的左、右心输出量之间具有极佳的相关性。志愿者的肺血流差异测量显示，右心输出量的55%流向右肺，45%流向左肺。患者的肺血流差异显示，大部分血流（81%）到达移植肺，仅有19%到达患者自身肺（SLTX：4.5±1.8升/分钟，患者自身肺：1.2±0.8升/分钟）。在正常志愿者与患者之间以及患者自身肺与移植肺的测量值之间，肺动脉的收缩期峰值平均速度和阻力指数存在显著差异（p < 0.05）。
VEC-MRI血流测量是监测SLTX术后肺血流动力学变化的一种有前景的非侵入性工具。
