背景:我们在动物模型中测试了完全非搏动循环和全植入式泵置换心室切除术后搏动循环对外周血管通透性的短期影响。
方法:用两个HeartMateIII连续流旋转泵对十头小牛进行心脏置换。在五头小牛中,快速调节泵速,以40次/分钟(PP)的速率赋予生理范围(10-25mmHg)的低频脉压.其余五只小牛得到无脉体循环的支撑,并且没有调节泵速(NP)。在心脏置换前(基线)和术后第1、7和14天(PODs)进行骨骼肌活检。测量骨骼肌组织含水量,并评估了骨骼肌的形态学改变。VE-钙黏着蛋白,磷酸-VE-钙粘蛋白,免疫组织化学分析CD31。
结果:基线时,组内或组间的组织含水量和骨骼肌形态没有显著变化,分别为POD1、7和14。VE-cadherin的表达和/或分布没有显著改变,磷酸-VE-钙粘蛋白,基线时骨骼肌脉管系统中的CD31,每组内或两组之间的PODs1、7和14,分别。尽管有或没有脉压的连续流全人工心脏(CFTAH)在POD7和14处引起组织含水量和组织学损伤评分略有增加,但未能达到统计学意义。
结论:CFTAH植入后,小牛骨骼肌微血管中没有明显的粘附连接蛋白降解和磷酸化,提示短期有或无脉压的CFTAH不会引起外周内皮损伤,也不会增加外周微血管通透性.
BACKGROUND: We tested the short-term effects of completely nonpulsatile versus pulsatile circulation after ventricular excision and replacement with total implantable pumps in an animal model on peripheral vascular permeability.
METHODS: Ten calves underwent cardiac replacement with two HeartMate III continuous-flow rotary pumps. In five calves, the pump speed was rapidly modulated to impart a low-frequency pulse pressure in the physiologic range (10-25 mm Hg) at a rate of 40 pulses per minute (PP). The remaining five calves were supported with a pulseless systemic circulation and no modulation of pump speed (NP). Skeletal muscle biopsies were obtained before cardiac replacement (baseline) and on postoperative days (PODs) 1, 7, and 14. Skeletal muscle-tissue water content was measured, and morphologic alterations of skeletal muscle were assessed. VE-cadherin, phospho-VE-cadherin, and CD31 were analyzed by immunohistochemistry.
RESULTS: There were no significant changes in tissue water content and skeletal muscle morphology within group or between groups at baseline, PODs 1, 7, and 14, respectively. There were no significant alterations in the expression and/or distribution of VE-cadherin, phospho-VE-cadherin, and CD31 in skeletal muscle vasculature at baseline, PODs 1, 7, and 14 within each group or between the two groups, respectively. Although continuous-flow total artificial heart (CFTAH) with or without a pulse pressure caused slight increase in tissue water content and histologic damage scores at PODs 7 and 14, it failed to reach statistical significance.
CONCLUSIONS: There was no significant adherens-junction protein degradation and phosphorylation in calf skeletal muscle microvasculature after CFTAH implantation, suggesting that short term of CFTAH with or without pulse pressure did not cause peripheral endothelial injury and did not increase the peripheral microvascular permeability.