Left ventricular full-thickness cardiomyoplasty with pericardial neoendocardium: experimental development of a...

Cardiomyoplasty, a surgical procedure using stimulated skeletal muscle graft to replace or repair damaged myocardium, has been successfully performed in experimental animals and clinical patients. Whenever feasible, endocardium of the damaged myocardial segment is retained and partial-thickness cardiomyoplasty should be carried out. However, if this procedure were to be applied to enlarge a hypoplastic ventricle or to maintain normal dimensions of the ventricular cavity in some repairs in adults, full-thickness replacement of the ventricular wall with contractile skeletal muscle mass would be required. To develop such a technique, several canine experiments were carried out. In 7 dogs, "simple full-thickness cardiomyoplasty" was performed by using a latissimus dorsi muscle graft to repair a full-thickness left ventricular wall defect. We found it was difficult to obtain adequate hemostasis between the nonscarred myocardial tissue and the skeletal muscle graft, and excessive suturing to obtain hemostasis resulted in strangulation of the muscle grafts. The skeletal muscle-blood interface in the left ventricle was found to be highly thrombogenic. The perioperative hemorrhage and the risk of muscle graft strangulation by excessive sutures were avoided by using a pericardial patch as neoendocardium in 5 dogs that underwent similar full-thickness cardiomyoplasty procedures. Although the pericardial neoendocardium was not fully antithrombogenic in this canine model, endothelialization of the endocardium occurred within several weeks after operation. Thus, when combined with an implantable synchronized burst stimulator, this technique may in the future provide an effective "full-thickness dynamic cardiomyoplasty" to enlarge the ventricles and augment myocardial function in select patients.