Mark T Stewart1, David E Haines2, Atul Verma3, Nicole Kirchhof4, Noah Barka4, Erin Grassl4, Brian Howard1. 1. Medtronic Cardiac Rhythm & Heart Failure, Minneapolis, Minnesota. 2. Oakland University William Beaumont School of Medicine, Beaumont Health System, Rochester, Michigan. Electronic address: david.haines2@beaumont.edu. 3. Southlake, Regional Health Centre, Newmarket, Canada. 4. Medtronic Physiological Research Laboratories, Minneapolis, Minnesota.
Abstract
BACKGROUND: Radiofrequency (RF) has become an accepted energy source for myocardial ablation but may result in discontinuous lesions and nontargeted tissue injury. We examined the feasibility and safety of lesion formation using high-amplitude, bipolar pulsed electric fields delivered from a multielectrode array catheter. OBJECTIVE: The purpose of this study was to compare duty-cycled radiofrequency ablation (RFA) to pulsed field ablation (PFA) in terms of acute electrical effects, 2-week lesion formation, and injury to nontargeted tissues. METHODS: Intracardiac ablations were performed in 6 pigs using a circular pulmonary vein ablation catheter. The energy source for ablation delivery was randomized to deliver either PFA or RFA to 3 atrial endocardial sites. Bipolar pace capture and electrogram amplitude measurements were recorded at each site. Histopathology and necropsies were performed after 2 weeks. RESULTS: The circular pulmonary vein ablation catheter was used to deliver pulsed electric fields to produce cardiac lesions without skeletal muscle stimulation. Evaluating all ablations in each site, electrogram amplitudes were reduced to <0.5 mV in 67.5% of PFA vs 27.0% of RFA deliveries (P <.001). Bipolar cardiac capture was lost after 100% vs 92.0% of PFA vs RFA (P = .005). At 2 weeks, PFA resulted in consistent transmural and homogeneous replacement fibrosis devoid of lingering myocyte "sequesters." RFA lesions showed a stronger inflammatory response extending to the epicardial fat, arterial injury, and thrombosis. Neither PFA nor RFA lesions showed endocardial thrombus. CONCLUSION: Intracardiac PFA can be feasibly delivered from a circular catheter to create fibrotic lesions that have acute electrical effects, without injury to nontargeted tissue.
BACKGROUND: Radiofrequency (RF) has become an accepted energy source for myocardial ablation but may result in discontinuous lesions and nontargeted tissue injury. We examined the feasibility and safety of lesion formation using high-amplitude, bipolar pulsed electric fields delivered from a multielectrode array catheter. OBJECTIVE: The purpose of this study was to compare duty-cycled radiofrequency ablation (RFA) to pulsed field ablation (PFA) in terms of acute electrical effects, 2-week lesion formation, and injury to nontargeted tissues. METHODS: Intracardiac ablations were performed in 6 pigs using a circular pulmonary vein ablation catheter. The energy source for ablation delivery was randomized to deliver either PFA or RFA to 3 atrial endocardial sites. Bipolar pace capture and electrogram amplitude measurements were recorded at each site. Histopathology and necropsies were performed after 2 weeks. RESULTS: The circular pulmonary vein ablation catheter was used to deliver pulsed electric fields to produce cardiac lesions without skeletal muscle stimulation. Evaluating all ablations in each site, electrogram amplitudes were reduced to <0.5 mV in 67.5% of PFA vs 27.0% of RFA deliveries (P <.001). Bipolar cardiac capture was lost after 100% vs 92.0% of PFA vs RFA (P = .005). At 2 weeks, PFA resulted in consistent transmural and homogeneous replacement fibrosis devoid of lingering myocyte "sequesters." RFA lesions showed a stronger inflammatory response extending to the epicardial fat, arterial injury, and thrombosis. Neither PFA nor RFA lesions showed endocardial thrombus. CONCLUSION: Intracardiac PFA can be feasibly delivered from a circular catheter to create fibrotic lesions that have acute electrical effects, without injury to nontargeted tissue.
Authors: Brian Howard; David E Haines; Atul Verma; Nicole Kirchhof; Noah Barka; Birce Onal; Mark T Stewart; Daniel C Sigg Journal: Circ Arrhythm Electrophysiol Date: 2022-06-01
Authors: Jacob S Koruth; Kenji Kuroki; Jin Iwasawa; Raju Viswanathan; Richard Brose; Eric D Buck; Elina Donskoy; Srinivas R Dukkipati; Vivek Y Reddy Journal: Europace Date: 2020-03-01 Impact factor: 5.214
Authors: Alan Sugrue; Vaibhav R Vaidya; Christopher Livia; Deepak Padmanabhan; Anas Abudan; Ameesh Isath; Tyra Witt; Christopher V DeSimone; Paul Stalboerger; Suraj Kapa; Samuel J Asirvatham; Christopher J McLeod Journal: PLoS One Date: 2020-02-21 Impact factor: 3.240
Authors: Jacob Koruth; Kenji Kuroki; Jin Iwasawa; Yoshinari Enomoto; Raju Viswanathan; Richard Brose; Eric D Buck; Molly Speltz; Srinivas R Dukkipati; Vivek Y Reddy Journal: Circ Arrhythm Electrophysiol Date: 2019-12-12
Authors: Brian Howard; David E Haines; Atul Verma; Douglas Packer; Nicole Kirchhof; Noah Barka; Birce Onal; Steve Fraasch; Damijan Miklavčič; Mark T Stewart Journal: Circ Arrhythm Electrophysiol Date: 2020-07-27