利用MRI测量健康受试者直立姿势下近端肺动脉血流特征：运动和年龄的影响。

Proximal pulmonary artery blood flow characteristics in healthy subjects measured in an upright posture using MRI: the effects of exercise and age.

作者信息

Cheng Christopher P, Herfkens Robert J, Taylor Charles A, Feinstein Jeffrey A

机构信息

Department of Mechanical Engineering, Stanford University, Stanford, California 94305-4038, USA.

出版信息

J Magn Reson Imaging. 2005 Jun;21(6):752-8. doi: 10.1002/jmri.20333.

DOI:10.1002/jmri.20333

PMID:15906332

Abstract

PURPOSE

To use MRI to quantify blood flow conditions in the proximal pulmonary arteries of healthy children and adults at rest and during exercise in an upright posture.

MATERIALS AND METHODS

Cine phase-contrast MRI was used to calculate mean flow and reverse flow index (RFI) in the main (MPA), right (RPA), and left (LPA) pulmonary arteries in healthy children and adults in an open-MRI magnet equipped with an upright MRI-compatible ergometer.

RESULTS

From rest to exercise (150% resting heart rate), blood flow (liters/minute/m2) increased in the RPA (1.4+/-0.3 vs. 2.5+/-0.4; P<0.001), LPA (1.1+/-0.3 vs. 2.2+/-0.6; P<0.001), and MPA (2.7+/-0.5 vs. 4.9+/-0.5; P<0.001). RFI decreased in the LPA (0.040+/-0.030 vs. 0.017+/-0.018; P<0.02) and MPA (0.025+/-0.024 vs. 0.008+/-0.007; P<0.03). Adults experienced greater retrograde flow in the MPA than the children (0.042+/-0.029 vs. 0.014+/-0.012; P<0.02).

CONCLUSION

It appears that at both rest and during exercise, in children and adults alike, RPA/LPA mean blood flow distribution is predominantly determined by distal vascular resistance, while retrograde flow is affected by proximal pulmonary bifurcation geometry.

摘要

目的

利用磁共振成像（MRI）对健康儿童和成人在静息状态及直立姿势运动时近端肺动脉的血流情况进行量化分析。

材料与方法

在配备直立式MRI兼容测力计的开放式MRI磁体中，采用电影相位对比MRI计算健康儿童和成人的主肺动脉（MPA）、右肺动脉（RPA）和左肺动脉（LPA）的平均血流量和反流指数（RFI）。

结果

从静息状态到运动状态（静息心率的150%），RPA的血流量（升/分钟/平方米）增加（1.4±0.3对2.5±0.4；P<0.001），LPA的血流量增加（1.1±0.3对2.2±0.6；P<0.001），MPA的血流量增加（2.7±0.5对4.9±0.5；P<0.001）。LPA和MPA的RFI降低（LPA：0.040±0.030对0.017±0.018；P<0.02；MPA：0.025±0.024对0.008±0.007；P<0.03）。成人MPA中的逆向血流比儿童更多（0.042±0.029对0.014±0.012；P<0.02）。