实验性静脉移植物中的肌内膜增厚取决于管壁张力。

Myointimal thickening in experimental vein grafts is dependent on wall tension.

作者信息

Schwartz L B, O'Donohoe M K, Purut C M, Mikat E M, Hagen P O, McCann R L

机构信息

Department of Surgery, Duke University Medical Center, Durham, NC 27710.

出版信息

J Vasc Surg. 1992 Jan;15(1):176-86. doi: 10.1067/mva.1992.33805.

DOI:10.1067/mva.1992.33805

PMID:1728676

Abstract

This study examines the relative contributions of intraluminal pressure, blood flow, wall tension, and shear stress to the development of myointimal thickening in experimental vein grafts. To study these different hemodynamic parameters, several experimental models were created in 30 New Zealand White rabbits separated into six groups: common carotid interposition vein grafts harvested at 4 weeks (VG-4) or 12 weeks (VG-12), common carotid-linguofacial vein arteriovenous fistulas harvested at 4 weeks (AVF-4) or 12 weeks (AVF-12), AVFs with partial outflow obstruction harvested at 4 weeks (AVFobs), and combination VG-AVFs in series harvested at 4 weeks (VGAVF). Blood pressure and flow in the graft or vein were measured by use of a transducer-tipped pressure catheter and electromagnetic flow meter. At harvest, veins were perfusion-fixed and proximal, middle, and distal sections were subjected to computerized morphometric analysis. Vein grafts were characterized by a high mean pressure (VG-4, 51 +/- 4; VG-12, 62 +/- 3 mm Hg), low mean flow (VG-4, 17 +/- 1; VG-12, 16 +/- 4 ml/min), large luminal area (VG-4, 19.7 +/- 2.4; VG-12, 19.3 +/- 3.9 mm2), high wall tension (VG-4, 17.0 +/- 1.5; VG-12, 19.5 +/- 2.4 x 10(3) dyne/cm), low shear stress (VG-4, 0.75 +/- 0.13; VG-12, 0.96 +/- 0.38 dyne/cm2), and a high degree of myointimal thickening (VG-4, 5.89 +/- 0.90; VG-12, 4.72 +/- 0.83 mm2). Arteriovenous fistulas were characterized by a low mean pressure (AVF-4, 5 +/- 1, AVF-12, 6 +/- 2 mm Hg), elevated blood flow (AVF-4, 82 +/- 16; AVF-12, 82 +/- 17 ml/min), small luminal area (AVF-4, 2.43 +/- 0.58; AVF-12, 7.14 +/- 2.68), low wall tension (AVF-4, 0.62 +/- 0.19; AVF-12, 0.89 +/- 0.24 x 10(3) dyne/cm), elevated shear stress (AVF-4, 108 +/- 32; AVF-12, 71 +/- 50 dyne/cm2), and decreased myointimal area (AVF-4, 1.18 +/- 0.26; AVF-12, 1.90 +/- 0.55 mm2). The addition of outflow obstruction to AVFs (AVFobs) resulted in elevated pressure (48 +/- 2 mm Hg), decreased flow (17 +/- 4 ml/min), larger luminal area (8.71 +/- 2.31 mm2), elevated wall tension (10.3 +/- 1.7 x 10(3) dyne/cm), and a degree of myointimal thickening approaching that of vein grafts (3.79 +/- 0.66 mm2).(ABSTRACT TRUNCATED AT 400 WORDS)

摘要

本研究探讨了管腔内压力、血流、血管壁张力和剪切应力对实验性静脉移植物肌内膜增厚形成的相对作用。为研究这些不同的血流动力学参数，在30只新西兰白兔中建立了几种实验模型，分为六组：4周（VG-4）或12周（VG-12）时获取的颈总动脉间置静脉移植物、4周（AVF-4）或12周（AVF-12）时获取的颈总动脉-舌面静脉动静脉瘘、4周时获取的伴有部分流出道梗阻的动静脉瘘（AVFobs）以及4周时获取的串联组合的VG-AVF（VGAVF）。使用带有传感器的压力导管和电磁流量计测量移植物或静脉中的血压和血流。取材时，对静脉进行灌注固定，并对近端、中间和远端节段进行计算机形态计量分析。静脉移植物的特点是平均压力高（VG-4，51±4；VG-12，62±3 mmHg）、平均血流低（VG-4，17±1；VG-12，16±4 ml/min）、管腔面积大（VG-4，19.7±2.4；VG-12，19.3±3.9 mm²）、血管壁张力高（VG-4，17.0±1.5；VG-12，19.5±2.4×10³达因/厘米）、剪切应力低（VG-4，0.75±0.13；VG-12，0.96±0.38达因/厘米²）以及肌内膜高度增厚（VG-4，5.89±0.90；VG-12，4.72±0.83 mm²）。动静脉瘘的特点是平均压力低（AVF-4，5±1，AVF-12，6±2 mmHg）、血流增加（AVF-4，82±16；AVF-12，82±17 ml/min）、管腔面积小（AVF-4，2.43±0.58；AVF-12，7.14±2.68）、血管壁张力低（AVF-4，0.62±0.19；AVF-12，0.89±0.24×10³达因/厘米）、剪切应力增加（AVF-4，108±32；AVF-12，71±50达因/厘米²）以及肌内膜面积减小（AVF-4，1.18±0.26；AVF-12，1.90±0.55 mm²）。给动静脉瘘增加流出道梗阻（AVFobs）导致压力升高（48±2 mmHg）、血流减少（17±4 ml/min）、管腔面积增大（8.71±2.31 mm²）、血管壁张力升高（10.3±1.7×10³达因/厘米）以及肌内膜增厚程度接近静脉移植物（3.79±0.66 mm²）。（摘要截断于400字）