Radiofrequency and Cryo-Ablation Effect on Transvenous Pacing and Defibrillatory Lead Integrity: An In Vitro Study

Abstract

Intorduction: Medical societies and cardiac implantable electronic device (CIED) manufacturers recommend avoiding close or direct contact between the body of transvenous leads and ablation catheters used to treat cardiac arrhythmias. These recommendations are made despite the lack of clinical studies. However, the target myocardium for successful ablation can be contiguous to CIED leads.

Methods and results: We examine in vitro the effects of direct application of radiofrequency (RF) and cryo-ablation energy on the integrity and functionality of CIED leads (excluding the pacing electrodes and defibrillation coils). A saline bath was created to mimic the body milieu. CIED leads, including all commercially available lead insulation materials, were connected to a CIED pulse generator and placed in direct contact with an ablation catheter in the tissue bath. RF and cryo-ablation energy were delivered under various conditions, including maximal ablation power, temperature, and impedance via the RF generator. CIED lead functionality, reflective of conductor integrity, was evaluated through lead impedance monitoring during ablation. CIED leads were then visually inspected, and examined with optic and electron microscopy as per protocol. A total of 42 leads were studied. All leads showed the absence of insulation damage at the site of ablation visually and with microscopy. Lead functionality was also preserved in all leads.

Conclusion: Catheter ablation in contact with CIED leads using radiofrequency or cryo-ablation in vitro did not affect lead body integrity and function despite aggressive ablation settings. It may be reasonable to perform ablation in contact with the body of CIED leads when clinically necessary.

Keywords: cardiac implantable electronic device leads; catheter ablation; cryo-ablation; implantable cardioverter defibrillator; pacemaker.

© 2016 Wiley Periodicals, Inc.

Figures

Figure 1

Experiment setting included RF generator (A), chicken breast on dispersive electrode in saline bath (B), centrifugal mini pump (C), and submergible water heater (D). Structures numbered in the saline bath as follows; ablation catheter (1), thermometer probe (2) and tested CIED lead (3).

Figure 2

Representative image of optic microscopy examination of lead at site of ablation showing the absence of insulation damage (× 10).

Figure 3

Representative image of electron microscopy examination of a tested lead at site of ablation showing the absence of insulation damage (× 800).