MR相位速度图及心导管检查对肺动脉血液动力学的对比研究

Hemodynamics of pulmonary arterial quantitative analysis:a comparative study of simultaneous phase-contrast MR imaging and cardiac catheterization study

目的 通过测量肺动脉瓣返流 (PR)、分析PR的峰值流速和计算肺动脉舒张压 (PADP) ,评价MR相位速度图检测肺动脉血液动力学的价值。方法 应用MR相位速度图测量了 45例患者的主肺动脉直径、流速及其最大返流速度并与右心导管检查进行了比较 ,通过直线相关与回归分析判断MR相位速度图测量PADP的准确性和特异性。结果 45例患者中 40例存在返流 ,MR相位速度图测定的PADP为 (4 82± 1 2 4)mmHg(1mmHg =0 133kPa) ,右心导管的测值为 (4 5 2± 2 0 0 )mmHg,二者间的相关性系数r=0 94(P <0 0 1) ,回归方程y =0 82x +4 5 8。其敏感性和特异性达 90 %。 2 5例肺动脉高压 (PAH)组主肺动脉的流速及肺血管的顺应性均低于非PAH组而返流的百分比显著性增高(P <0 0 5 ) ,返流量与肺动脉平均压呈正相关 (r =0 89,P <0 0 1) ,与肺动脉峰值流速呈负相关 (r =- 0 82 ,P <0 0 1)。结论 MR相位速度图是评价肺动脉血液动力学变化的一种非创伤性新技术 ,能较准确地评价PR患者的PADP。

Objective To assess hemodynamics of pulmonary arterial flow and to count the pulmonary artery diastolic pressure (PADP) by analysis using velocity study of main pulmonary with phase-contrast MR imaging. Methods The diameter、velocity and the maximal retrograde velocity of main pulmonary artery in 45 patients were measured with phase-contrast MR imaging and compared with cardiac catheterization. The accuracy and specificity of PADP measured with phase-contrast MR imaging were evaluated by relativity and regression analysis. Results The PADP measured with phase-contrast MR imaging was (4.82±1.24) mm Hg and that measured with right cardiac catheterization was (4.52±2.00) mm Hg in 40 patients with pulmonary regurgitation. With good correlation the correlation coefficient was 0.94(P<0.01) and the regression equation was y=0.82x+ 4.58. The sensitivity and specificity was higher than 90%. The velocity and distensibility of the main pulmonary artery in 25 cases with pulmonary arterial hypertension (PAH) were all significantly decreased. However the percentage of retrograde flow was significantly increased(P<0.05). In addition, the retrograde quantity had positive correlation with mean pressure of main pulmonary(r=0.89,P<0.01)and negative correlation with peak value of main pulmonary(r=-0.82,P<0.01). Conclusion Phase-contrast MR imaging is a new technique for evaluation of hemodynamics of pulmonary arterial flow and could judge PADP in patient with pulmonary regurgitation accurately.