Preventing phrenic nerve stimulation by a patch insulation in an intact swine heart model

• Published in: PloS one Vol. 9; no. 7; p. e102608
• Main Authors: Huang, Jin-Long, Lin, Yenn-Jiang, Hung, Yi-Wen, Hsieh, Yu-Cheng, Cheng, Chien-Ming, Wang, Kuo-Yang
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.07.2014; Public Library of Science (PLoS)
• Subjects: Animals; Biology and Life Sciences; Cardiac Pacing, Artificial - adverse effects; Cardiac Pacing, Artificial - methods; Cardiac Resynchronization Therapy; Cardiac Surgical Procedures; Cardiology; Cardiovascular diseases; Clinical medicine; Configurations; Defibrillators; Defibrillators, Implantable - adverse effects; Electrodes; Electrodes, Implanted - adverse effects; Grafting; Heart; Heart failure; Heart Ventricles - innervation; Heart Ventricles - surgery; Hospitals; Implantation; Insulation; Laboratory animals; Livestock; Medicine and Health Sciences; Ostomy; Phrenic nerve; Phrenic Nerve - physiology; Polytetrafluoroethylene; Stimulation; Swine; Ventricle; Ventricular Dysfunction, Left - therapy; Veterinary medicine; United States > US; Taiwan
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0102608

Phrenic nerve stimulation (PNS) could be prevented by a silastic patch over the epicardial lead. We studied the effects in preventing PNS by placing a silastic patch directly over an epicardial lead or placing a graft around the phrenic nerve (PN). Fourteen Lanyu swine were enrolled. A bipolar lead was placed epicardially on the left ventricle (LV) inferior to the PN. An implantable cardioverter-defibrillator (ICD) lead was placed into the right ventricle (RV). The maximal influential distance (MID) was measured under 3 pacing configurations to express the influential electrical field on the PN. The threshold of the LV and PN were evaluated epicardially. Then, PTFE patches of different sizes (10×10 mm, 20×20 mm and 30×30 mm) were placed between the LV lead and PN to study the rise in PN threshold in 7 swine. On the other hand, the PN were surrounded by a PTFE graft of different lengths (10 mm, 20 mm, and 30 mm) in the remaining 7 swine. LV-bipolar pacing showed the shortest MID when compared to the other 2 unipolar pacing configurations at pacing voltage of 10 V. The patch was most effective in preventing PNS during LV-bipolar pacing. PNS was prevented under all circumstances with a larger PTFE patch (30×30 mm) or long graft (30 mm). PNS was avoided by placing a PTFE patch over the LV lead or a graft around the PN despite pacing configurations. Hence if PNS persisted during CRT implantation, a PTFE patch on the LV lead or a graft around the PN could be considered.