Myocardial blood flow distribution in concentric left ventricular hypertrophy.
Myocardial blood flow distribution in concentric left ventricular hypertrophy.
复制标题
向心性左心室肥厚的心肌血流分布。
DOI：
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发表时间：
1978
影响因子：
15.9
通讯作者：
J. Greenfield
中科院分区：
文献类型：
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作者：
J. Rembert;L. Kleinman;J. Fedor;A. Wechsler;J. Greenfield
在八只长期保持清醒状态的狗中研究了控制条件和缺血引起的血管舒张期间的局部心肌血流量。其中七只狗在 6 周龄时进行了升主动脉缩窄带术，另一只狗患有先天性瓣膜下主动脉狭窄。该组的平均左心室重量为157+/-7.6g，左心室体重比为8.76+/-0.47g/kg。所有动物均未表现出充血性心力衰竭的迹象。在控制状态期间，平均左心室收缩压为249+/-12mmHg，左心室舒张末压为11.5+/-0.5mmHg。主动脉舒张压为74+/-6毫米汞柱。冠状动脉左回旋支平均血流量为 71+/-6 cm(3)/min。在具有缩窄带的动物中，52+/-6% 的血流发生在收缩期。在患有先天性瓣膜下主动脉狭窄的狗中，5%的冠状动脉血流是收缩期的。静息状态下的平均跨壁血流量为 0.97+/-0.08 cm(3)/min/g，心内膜与心外膜血流 (endo/epi) 之比为 0.88+/-0.07。反应性充血期间，平均透壁血流量增加至 3.5+/-0.30 cm(3)/min/g；然而，endo/epi 下降至 0.52+/-0.06。这些研究记录了正常左心室和肥厚左心室之间跨壁血流分布的差异：在静息状态下，正常心室中，最高流量出现在心内膜层，而在肥厚心室中，最高流量出现在中层心内膜流量小于心外膜流量。在缺血引起的血管舒张期间，异常的内皮/外皮变得明显加剧。这些数据表明，在需要高流量的情况下，具有明显同心左心室肥厚的心脏的心内膜层可能无法充分灌注。
Regional myocardial blood flow during both control conditions and ischemia-induced vasodilatation was studied in eight chronically instrumented awake dogs. Seven of these animals had coarctation-banding of the ascending aorta performed at 6 wk of age, and the other dog had congenital subvalvular aortic stenosis. The mean left ventricular weight for the group was 157+/-7.6 g, and the left ventricular body weight ratio was 8.76+/-0.47 g/kg. None of the animals exhibited signs of congestive heart failure. During the control state, the mean left ventricular systolic pressure was 249+/-12 mm Hg and the left ventricular end-diastolic pressure was 11.5+/-0.5 mm Hg. The aortic diastolic pressure was 74+/-6 mm Hg. Mean left circumflex coronary artery blood flow was 71+/-6 cm(3)/min. In the animals with coarctation-banding, 52+/-6% of the flow occurred during systole. In the dog with congenital subvalvular aortic stenosis, 5% of the coronary flow was systolic. Mean transmural blood flow during resting conditions was 0.97+/-0.08 cm(3)/min per g, and the ratio of endocardial to epicardial flow (endo/epi) was 0.88+/-0.07. During reactive hyperemia, the mean transmural blood flow increased to 3.5+/-0.30 cm(3)/min per g; however, the endo/epi decreased to 0.52+/-0.06.THESE STUDIES DOCUMENT A DIFFERENCE IN TRANSMURAL BLOOD FLOW DISTRIBUTION BETWEEN THE NORMAL AND THE HYPERTROPHIED LEFT VENTRICLE: during resting conditions, in the normal ventricle, the highest flow occurs in the endocardial layer, whereas in the hypertrophied ventricle, the highest flow is in the middle layers with the endocardial flow less than the epicardial flow. During ischemia-induced vasodilatation, the abnormal endo/epi becomes accentuated markedly. These data demonstrate that, in situations requiring high flow, the endocardial layer of a heart with marked concentric left ventricular hypertrophy may not be perfused adequately.