HYBRID ASSISTED CIRCULATION DEVICE DRIVEN BY AUTOSKELETAL MUSCLE

自1987年我们开展心肌成形术的基础研究以来，已经积累了有关骨骼肌获得抗疲劳能力的基础数据，包括转化、血流动力学改善和输出量。基于这些信息，我们进行了实验，以阐明骨骼肌的基本能力，并开发出一种由骨骼肌驱动的实验性辅助循环装置。利用血管模板的方法，分析了除胸背血管外，切断胸背血管的狗背阔肌的血液循环变化。小动脉从控制胸背血管的区域发展到失去血运的区域，导致血液循环的恢复。这一发现可能对克服肌肉疲劳的问题很重要。在一项使用成年狗的急性实验中，制造了一种由背阔肌驱动的辅助循环装置，并测定了其输出特性。结果表明，短时间内背阔肌有足够的输出量来辅助心脏功能，而由于疲劳而不可能持续供应足够的输出量。尽管狗的数量太少，无法获得有效的结果，但背阔肌可能有足够的输出量来驱动泵以辅助心脏功能。需要进一步的研究：1)有效利用背阔肌的输出量需要什么类型的泵？以及2)经预处理的背阔肌(血管延迟和预适应)是否会导致抗疲劳导致泵的长时间运行？

Since the initiation of our basic research in 1987 relating to cardiomyoplasty, fundamental data concerning acquisition of resistance to fatigue by skeletal muscle, including transformation, improvement in hemodynamics, and output, have been accumulated.Based on this information, experiments were performed to elucidate the basic capacity of skeletal muscle and to develop an experimental assisted circulation device driven by skeletal muscle.Using a method of vascular template, changes in blood circulation in the latissimus dorsi which were devascularized except for the thoracodorsal vessels were analyzed in dogs. Development of arterioles from the region in control of the thoracodorsal vessels to the devascularized region led to restoration of blood circulation. This finding may be important to overcome the problem of muscular fatigue.In an acute experiment using adult dogs, an assisted circulation device driven by the latissimus dorsi was produced, and its output characteristics were determined. The results suggest that the latissimus dorsi has sufficient output to assist cardiac function for a short period of time, while sustained supply of sufficient output was impossible because of fatigue. Although the number of dogs used was too small to obtain valid results, the latissimus dorsi may have sufficient output to drive a pump for assistance of cardiac function.Future studies are needed to study the following : 1) What type of pump is required for efficient utilization of the output from the latissimus dorsi? ; and 2) Does the pretreated latissimus dorsi (vascular delay and preconditioning) results in fatigue resistance leading to prolonged operation of the pump?