Borges A C, Wensel R, Opitz C, Bauer U, Baumann G, Kleber F X
Medical Department I, Humboldt-University Berlin, Charité, Germany.
Eur Heart J. 1997 Dec;18(12):1988-94. doi: 10.1093/oxfordjournals.eurheartj.a015210.
Intravascular ultrasound imaging of the pulmonary arteries has been demonstrated to be a reliable method of quantifying vessel diameter, luminal area and pulsatility. Simultaneous measurement of flow velocity and its response to vasodilators allows the relationship between morphology and functional compromise to be studied, especially endothelial dysfunction.
In 51 patients (mean age = 49.8 +/- 12.6 years, 17 female) we performed right heart catheterization and simultaneous intravascular ultrasound of pulmonary artery branches. The patients were divided in two groups: group 1 with normal pulmonary artery pressure and pulmonary vascular resistance, and group 2 with pulmonary hypertension (peak pulmonary artery pressure > 30 mmHg and/or mean pulmonary artery pressure > 20 mmHg). Vessel wall and lumen were studied using a 2.9 F intravascular ultrasound catheter with a 30 MHz phased array transducer. Measurement of blood flow velocity was accomplished by a Doppler flow wire (0.018 inch). The maximal flow change during acetylcholine infusion (adjusted to 10(-6); 10(-5), and 10(-4) M concentration in the blood vessel) was measured.
There were no significant differences between groups 1 and 2 with respect to age (48.5 +/- 14.3 years vs 50.3 +/- 12.3 years; P = ns), gender (4 female/8 male vs 13 female/26 male; P = ns), luminal area of the vessel segment in which the intravascular ultrasound measurements were obtained (11.8 +/- 6.1 mm2 vs 16.7 +/- 14.3 mm2; P = ns), internal diameter (3.9 +/- 1.2 mm vs 4.2 +/- 1.7 mm; P = ns), and external diameter (6.1 +/- 1.3 mm vs 6.9 +/- 2.1 mm; P = ns). Cross-sectional images of the pulmonary artery wall demonstrated a single ring with high echodensity with a thin inner layer regarded as intima in group 1. In contrast, the majority of patients (n = 35/39) in group 2 demonstrated a thickening of the intimal layer and/or a disturbance of layering of the echogenic arterial wall. The relative wall thickness was higher in group 2 than in group 1 (22.5 +/- 10.4% vs 15.3 +/- 6.5%; P < 0.05). There were no significant correlations between pulmonary artery pressure and wall thickness pulmonary artery pressure and area change in the cardiac cycle, acetylcholine-dependent increase in pulmonary flow and morphological changes in the vessel wall.
We conclude that intravascular ultrasound is capable of detecting morphological changes in the pulmonary vessel wall in pulmonary hypertension and that vessel wall hypertrophy of small pulmonary segment arteries, as detected by intravascular ultrasound, is not predictive of functional vasodilatory response of resistance vessels of the same vessel area.
肺动脉血管内超声成像已被证明是一种量化血管直径、管腔面积和搏动性的可靠方法。同时测量流速及其对血管扩张剂的反应，有助于研究形态学与功能损害之间的关系，尤其是内皮功能障碍。
对51例患者（平均年龄=49.8±12.6岁，女性17例）进行了右心导管检查及肺动脉分支的同步血管内超声检查。患者分为两组：1组肺动脉压力和肺血管阻力正常，2组患有肺动脉高压（肺动脉峰值压力>30 mmHg和/或平均肺动脉压力>20 mmHg）。使用带有30 MHz相控阵换能器的2.9 F血管内超声导管研究血管壁和管腔。通过多普勒血流导线（0.018英寸）测量血流速度。测量乙酰胆碱输注期间（调整至血管内浓度为10⁻⁶、10⁻⁵和10⁻⁴ M）的最大血流变化。
1组和2组在年龄（48.5±14.3岁对50.3±12.3岁；P=无统计学意义）、性别（4例女性/8例男性对13例女性/26例男性；P=无统计学意义）、获得血管内超声测量的血管节段的管腔面积（11.8±6.1 mm²对16.7±14.3 mm²；P=无统计学意义）、内径（3.9±1.2 mm对4.2±1.7 mm；P=无统计学意义）和外径（6.1±1.3 mm对6.9±2.1 mm；P=无统计学意义）方面无显著差异。肺动脉壁的横截面图像显示，1组中内膜被视为薄内层的高回声单环。相比之下，2组中的大多数患者（n=35/39）表现出内膜层增厚和/或回声动脉壁分层紊乱。2组的相对壁厚度高于1组（22.5±10.4%对15.3±6.5%；P<0.05）。肺动脉压力与壁厚度、肺动脉压力与心动周期中的面积变化、乙酰胆碱依赖性肺血流增加与血管壁形态学变化之间无显著相关性。
我们得出结论，血管内超声能够检测肺动脉高压时肺血管壁的形态学变化，并且血管内超声检测到的小肺段动脉的血管壁肥厚并不能预测相同血管区域阻力血管的功能性血管舒张反应。
