Transformation of Denervated Sleletal Muscle Graft By Chronic Electrical Stimulation and Application of Sleletal Muscle Graft for Reconstructive Cardiovascular Surgery.

目的：本实验研究的目的是探讨慢性电刺激下去神经骨骼肌移植物避免肌肉萎缩的新手术方式的可行性，以及节律性骨骼肌心室（SMV）动态Fontan手术维持生理肺循环的可行性。方法：初步实验10只beagle，胸背神经交易后电刺激左背阔肌移植物28 d，观察慢性刺激对去神经支配性萎缩的逆转作用。在初步研究的基础上，我们利用10只狗的背阔肌构建了带骨骼肌心室（SMV）的动态Fontan模型，研究了其辅助肺循环的潜力。SMV电预处理8周。体外循环（CPB）下建立右心（RV）旁路模型，右心房与肺干之间吻合SMV。SMV以25Hz， 60/min的突发频率定速。，即不同步比率。测量主动脉压（AoP）、肺动脉压（PAP）、中心静脉压（CVP）和肺流量（PAF）。结果：刚给药后，PAP和PAF升高，CVP降低。CVP由17±1.4 mmHg降至13.5±0.7 mmHg （p<0.05）。PAP由20±2.8/19±1.6 mmHg（非脉动流）增加至37.5±4.9/18±2.1 mmHg（脉动流）。off-SMV下CVP为18 mmHg，严重的RV衰竭被认为是PAF为术前的35%。在on-SMV下，CVP降低，PAF与术前基本相同。在生理CVP上，胸内SMV的RV旁路模型在高Rp下保持与术前相同的PAF。我们的结论是，该模型可能是高Rp的单室心脏的可行的手术选择，这可能不是Fontan的候选人。

PURPOSE : The purpose of this experimental study is to test the possibility of new surgical procedures of with denervated skeletal muscle graft with chronic electrical stimulation to avoid muscle atrophy, and the feasibility of dynamic Fontan procedure by paced skeletal muscle ventricle(SMV) to maintain physiological pulmonary circulation.METHODS : Preliminary experiments in 10 beagles, left lattissimus dorsi muscle grafts were electrically stimulated for 28 days after the transaction of thoracodorsal nerve to test the effects of chronic stimulation on reversal of denervation-induced atrophy. On the basis of preliminary studies, we have studied potential for pulmonary circulational assist by dynamic Fontan model with Skeletal Muscle Ventricle(SMV) construced using the latissimus dorsi muscles of 10 dogs. SMV was electrical preconditioned for 8 weeks. Under cardiopulmonary bypass(CPB), right heart(RV) bypass model was established with SMV anastomosed between the right atrium and pulmonary trunk. SMV was paced at a burst frequency of 25Hz, 60/min., an asynchronization ratio. Aortic pressure(AoP), pulmonary arterial pressure(PAP), central venous pressure(CVP), and pulmonary flow(PAF) were measured.RESULTS : Just after on-SMV, PAP and PAF were increased, CVP was decreased. CVP was decreased from 17±1.4 mmHg to 13.5±0.7 mmHg (p<0.05). PAP was increased from 20±2.8/19±1.6 mmHg (non-pulsatile flow) to 37.5±4.9/18±2.1 mmHg (pulsatile flow). Under off-SMV CVP was 18 mmHg and severe RV failure was recognized as PAF was 35% of preoperation. Under on-SMV, CVP was decreased and PAF was almost same as preoperation. On physiological CVP, RV bypass model with intrathoracic SMV keeped PAF as same as preoperation under high Rp. We conclued that this model may be aviable surgical option for univentricular heart with high Rp, which may not be a Fontan candidates.