Experimental Aortic Stenosis in Fetal Lambs
Experimental Aortic Stenosis in Fetal Lambs
复制标题
胎羔实验性主动脉瓣狭窄
DOI：
10.1161/01.cir.62.6.1159
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发表时间：
1980
期刊：
影响因子：
37.8
通讯作者：
Rosemarie Hartwig R.N.
中科院分区：
文献类型：
--
作者：
D. Levin;R. Perkin;M. Parkey;E. Mayhew;Rosemarie Hartwig R.N.
Morphologic analyses of lungs from infants who died of severe aortic stenosis shortly after birth have shown increased pulmonary vascular smooth muscle and an increased number of pulmonary resistance vessels. These findings have been thought to be caused by in utero pulmonary venous, pulmonary arterial or right ventricular hypertension. To study this problem in the fetus, we created aortic stenosis in 10 fetal lambs (97-115 days gestation). Fetuses were reoperated upon at 133-141 days gestation (mean 32.6 days aortic stenosis). The left ventricular-to-systemic arterial systolic blood pressure difference was measured in three fetuses and was abnormal (18, 22 and 22 mm Hg). Pulmonary arterial blood pressure was measured in three fetuses and was normal (54-58 mm Hg mean). At autopsy, aortic stenosis was severe and the aortic diameter reduced (1.7 ± 1.0 mm vs 6.1 ± 0.7 mm for controls, p < 0.01). Heart weight was greater in aortic stenosis (21.5 ± 8.8 g) compared with control (17.2 ± 5.8 g, p < 0.01). This was the result of increased left ventricular free wall weight (aortic stenosis 9.79 ± 7.73 g vs control 5.46 ± 2.26 g, p < 0.01) and thickness (aortic stenosis 7.3 ± 1.5 mm vs control 5.1 + 1.7 mm, p <0.05). Lungs of six fetuses were fixed by perfusion and 331 fifth-generation resistance vessels were measured. Medial width (m) was decreased in aortic stenosis (4.82 ± 0.66 μ) compared with vessels from six control fetuses (6.19 ± 1.70μ, n = 529, p < 0.002). External diameter (d) was also decreased in aortic stenosis (22.18 ± 1.37μ) compared with control vessels (39.05 ± 10.15 μ, p < 0.01), resulting in an increased m/d ratio in aortic stenosis (0.22 i 0.03) compared with control vessels (0.16 ± 0.04, p < 0.007). The number of small muscular vessels per cm' lung tissue was decreased in aortic stenosis (74.3 ± 27.2/cm') compared with control lungs (167.3 ± 3.9/cm', p < 0.004). Differences between these findings and findings in human infants' lungs may be the result both associated lesions and age at time of death in human infants.
