Acute and Chronic Performance Evaluation of a Novel Epicardial Pacing Lead Placed by Percutaneous Subxiphoid Approach in a Canine Model

Abstract

The basic design for the intrapericardial leads (IPLs) used a diamond-shaped loop for stability at the distal end and a preshaped lead body within the diamond loop in which the bipolar, nonsteroid eluting, electrodes were located (Figure 1). The electrodes were titanium nitride-coated platinum iridium, 5 mm 2 in dimension © 2015 American Heart Association, Inc. Original ArticleBackground-Endovascularly implanted leads risk vascular injury and endocarditis, and can be difficult to locate in desired positions for LV pacing. We evaluated the acute and long-term stability, electric performance and histopathology of a percutaneously placed intrapericardial lead (IPL). Methods and Results-Twelve adult mongrel dogs underwent defibrillator implants incorporating IPLs. Successful uncomplicated percutaneous implantation of an IPL was achieved in all. Early fluoroscopic shift noted with 3 of 6 of the initial version IPL-1 was not seen with the modified IPL-2. Mean±95% confidence interval bipolar capture threshold at 0.5-ms pulse width for the IPL increased from 0.69±0.14 V at implant to 1.50±0.34 V (P=0.003) at 12 weeks. The 12-week thresholds were higher for IPL compared with right ventricular endocardial leads (0.75±0.33 V; P=0.001) but not different compared with coronary sinus leads (1.33±0.58 V; P=0.994). IPL impedance increased from 742±46 Ω at implant to 1066±207 Ω at 12 weeks (P=0.007). R-wave amplitude at 12 weeks was 8.37±1.52 mV. There was no important phrenic nerve stimulation from IPL pacing. Histopathology in 8 animals showed adequate adhesion of the electrodes or mesh to the epicardium without damage to underlying vasculature. There was no evidence for late pericardial inflammation or effusion. Conclusions-The IPL demonstrated adequate stability of position and acceptable electric parameters without chronic pericardial inflammation in this canine model and offers a potential alternative to endocardial pacing leads.

Minimally Invasive Implantation of a Micropacemaker Into the Pericardial Space

“…18 John et al developed and implanted an intrapericardial pacing leads in 12 dogs using a novel passive fixation lead system. 19 Similarly, Clark et al demonstrated feasibility of implanting a defibrillator lead with a “side biting” tine through a pericardial sheath. 20,21 An additional approach towards extravascular pacing demonstrated successful ventricular capture using a substernal electrode.…”

Leadless cardiac pacing systems: current status and future prospects

“…This innovative pacemaker concept was feasible, yet 1 out of 6 piglets developed a pneumothorax during implantation [53]. Thirdly, John et al described an effective percutaneous placement of an intrapericardial pacemaker lead by using a subxiphoid approach in a pre-clinical setting [54]. Fourthly, the SPACE study established the feasibility of delivering epicardial pacing therapy within the substernal anterior mediastinum in 18 out of 26 patients [55].…”

An Overview on the Considerations for the Planning of Nonclinical Necropsies for Medical Device Studies

“…Introduction and discussions regarding some existing medical device animal models include: the biocompatibility testing of novel materials (e.g., polymers) in the subcutaneous, bone, or muscle tissues of the rat or rabbit (ISO 10993-6); cardiovascular and other devices in the swine and/or sheep (Swindle et al 2012; Sartoretto et al 2016); skin wound healing in swine (Seaton, Hocking, and Gibran 2015); critical defect bone healing in sheep, rabbits, and rats (Cooper et al 2010; Wancket 2015); and electrophysiology devices in canine (John et al 2015).…”