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

目的：探讨电刺激失神经支配骨骼肌移植物避免肌肉萎缩的新手术方法的可行性，以及通过起搏骨骼肌室(SMV)动态Fontan手术维持生理性肺循环的可行性。方法：在10只比格犬的左侧背阔肌移植物上进行电刺激28d，以检测慢性刺激对去神经支配所致萎缩的逆转作用。在初步研究的基础上，我们用10只狗的背阔肌建立动态Fontan模型，研究其对肺循环辅助作用的可能性。SMV电预处理8周。在体外循环(CPB)下，右心房和肺动脉干之间吻合SMV建立右心转流模型。SMV的起搏频率为25赫兹，60次/分钟，为异步化比率。测量主动脉压(AOP)、肺动脉压(PAP)、中心静脉压(CVP)、肺血流量(PAF)。结果：On-SMV后即刻，PAP、PAF升高，CVP降低。中心静脉压从17±1.4 mm Hg降至13.5±0.7 mm Hg(p&lt；0.05)。PAP由20±2.8/19±1.6 mm Hg(非搏动性血流)增至37.5±4.9/18±2.1 mm Hg(搏动性血流)。在Off-SMV模式下，CVP为18 mm Hg，严重右室衰竭为PAF的35%。在On-SMV模式下，CVP降低，PAF与术前无明显差异。在生理性CVP、胸腔内SMV维持PAF的RV搭桥模型上，高RP状态下维持与术前相同的PAF。我们的结论是，该模型可能是治疗Rp升高的单室心脏的一种可行的手术选择，这可能不是Fontan的候选方案。

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.