Kikuchi Y, Shiraishi H, Igarashi H, Yanagisawa M
Department of Pediatrics, Jichi Medical School, Tochigi, Japan.
Acta Paediatr Jpn. 1996 Feb;38(1):32-5. doi: 10.1111/j.1442-200x.1996.tb03431.x.
A preliminary experimental study in dogs was conducted to evaluate the feasibility of transvenous cardiac pacing in the fetus with complete heart block associated with hydrops. Four young mongrel dogs were anesthetized with intravenous administration of sodium pentobarbital and mechanically ventilated, and a pacing lead was inserted via the tricuspid valve. The right ventricular cardiac output, aortic pressure and central venous pressure were measured, and the tricuspid valve regurgitation was measured semi-quantitatively using echo-Doppler color flow imaging. The relationship between the location of the pacing lead and the tricuspid valve regurgitation and cardiac function was examined. The mean right ventricular cardiac output when the pacing lead was inserted into the superior vena cava (126 +/- 54 mL/min per kg) was not significantly different from that when it was inserted into the right ventricle (110 +/- 43 mL/min per kg). The aortic pressure was 66 +/- 7.7 mmHg and 67 +/- 6.6 mmHg, respectively, and the central venous pressure 5.9 +/- 1.7 mmHg and 5.7 +/- 1.6 mmHg, respectively, under the two conditions (not significantly different). The ratio of demonstrating significant tricuspid valve regurgitation was 4/13 into the superior vena cava and 5/13 into the right ventricle, respectively (not significantly different). The location of the pacing lead did not change the cardiac function or the amount of the tricuspid valve regurgitation in our experimental study. It was therefore concluded that the transvenous cardiac pacing technique has potential application in intrauterine transvenous cardiac pacing in the fetus with complete heart block.
进行了一项针对犬类的初步实验研究，以评估经静脉心脏起搏用于患有水肿的完全性心脏传导阻滞胎儿的可行性。四只年轻的杂种犬通过静脉注射戊巴比妥钠麻醉并进行机械通气，通过三尖瓣插入起搏导线。测量右心室心输出量、主动脉压和中心静脉压，并使用超声多普勒彩色血流成像半定量测量三尖瓣反流。研究了起搏导线位置与三尖瓣反流及心脏功能之间的关系。当起搏导线插入上腔静脉时，平均右心室心输出量为（每千克体重126±54毫升/分钟），与插入右心室时（每千克体重110±43毫升/分钟）相比无显著差异。在两种情况下，主动脉压分别为66±7.7毫米汞柱和67±6.6毫米汞柱，中心静脉压分别为5.9±1.7毫米汞柱和5.7±1.6毫米汞柱（无显著差异）。显示明显三尖瓣反流的比例分别为插入上腔静脉时13例中有4例，插入右心室时13例中有5例（无显著差异）。在我们的实验研究中，起搏导线的位置并未改变心脏功能或三尖瓣反流的程度。因此得出结论，经静脉心脏起搏技术在患有完全性心脏传导阻滞的胎儿宫内经静脉心脏起搏方面具有潜在应用价值。
