THORACOSCOPIC PLACEMENT OF IMPLANTABLE CARDIOVERTER-DEFIBRILLATOR PATCH LEADS IN SHEEP

Background. A thoracoscopic technique was developed for the placement of commercially available implantable cardioverter-defibrillator (ICD) patch leads in sheep. Methods and Results. Small ICD patch leads (13.5 cm2, A-67) were placed thoracoscopically in sheep (n=5) that had survived coronary artery ligation from a previous experiment. The technique used three small incisions in the left chest. After lysis of adhesions, the ICD patch lead was introduced through a mediastinoscope. The ICD patch lead was secured in the extrapericardial position with surgical clips placed in the four corners of the ICD patch lead. After 2 weeks, a median sternotomy was performed, and ICD patch leads were reexamined for positioning. Extensive fibrosis was noted to adhere the ICD patch lead to the pericardium. The surgical clips were found intact in all animals without noticeable migration of patch lead position. There was no mortality related to ICD patch lead placement, and estimated blood loss was less than 30 mL without use of cautery. Conclusions. Commercially available ICD patch leads may be reliably and safely placed with minimal patch migration in sheep using thoracoscopic techniques.