title: Combined leadless pacemaker and subcutaneous implantable defibrillator therapy: feasibility, safety, and performance.
abstract: OBJECTIVE
  The subcutaneous implantable cardioverter-defibrillator (S-ICD) and leadless pacemaker (LP) are evolving technologies that do not require intracardiac leads. However, interactions between these two devices are unexplored. We investigated the feasibility, safety, and performance of combined LP and S-ICD therapy, considering (i) simultaneous device-programmer communication, (ii) S-ICD rhythm discrimination during LP communication and pacing, and (iii) post-shock LP performance.
  
  
  RESULTS
  The study consists of two parts. Animal experiments: Two sheep were implanted with both an S-ICD and LP (Nanostim, SJM), and the objectives above were tested. Human experience: Follow-up of one S-ICD patient with bilateral subclavian occlusion who received an LP and two LP (all Nanostim, SJM) patients (without S-ICD) who received electrical cardioversion (ECV) are presented. Animal experiments : Simultaneous device-programmer communication was successful, but LP-programmer communication telemetry was temporarily lost (2 ± 2 s) during ventricular fibrillation (VF) induction and 4/54 shocks. Leadless pacemaker communication and pacing did not interfere with S-ICD rhythm discrimination. Additionally, all VF episodes (n = 12/12), including during simultaneous LP pacing, were detected and treated by the S-ICD. Post-shock LP performance was unaltered, and no post-shock device resets or dislodgements were observed (24 S-ICD and 30 external shocks). Human experience : The S-ICD/LP patient showed adequate S-ICD sensing during intrinsic rhythm, nominal, and high-output LP pacing. Two LP patients (without S-ICD) received ECV during follow-up. No impact on performance or LP dislodgements were observed.
  
  
  CONCLUSIONS
  Combined LP and S-ICD therapy appears feasible in all animal experiments (n = 2) and in one human subject. No interference in sensing and pacing during intrinsic and paced rhythm was noted in both animal and human subjects. However, induced arrhythmia testing was not performed in the patient. Defibrillation therapy did not seem to affect LP function. More data on safety and performance are needed.
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands f.v.tjong@amc.uva.nl.
authors.forename: F V Y
authors.initials: FV
authors.lastname: Tjong
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: T F
authors.initials: TF
authors.lastname: Brouwer
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: L
authors.initials: L
authors.lastname: Smeding
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: K M
authors.initials: KM
authors.lastname: Kooiman
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: J R
authors.initials: JR
authors.lastname: de Groot
authors.affiliation: St Jude Medical, Sunnyvale, CA, USA.
authors.forename: D
authors.initials: D
authors.lastname: Ligon
authors.affiliation: Boston Scientific Corporation, St Paul, MN, USA.
authors.forename: R
authors.initials: R
authors.lastname: Sanghera
authors.affiliation: Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: M J
authors.initials: MJ
authors.lastname: Schalij
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: A A M
authors.initials: AA
authors.lastname: Wilde
authors.affiliation: AMC Heart Center, Department of Clinical and Experimental Cardiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands.
authors.forename: R E
authors.initials: RE
authors.lastname: Knops
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D001145:Arrhythmias, Cardiac / Q000628:therapy*; D003131:Combined Modality Therapy; D017147:Defibrillators, Implantable / Q000592:standards*; D004554:Electric Countershock / Q000295:instrumentation*; D004562:Electrocardiography; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009426:Netherlands; D010138:Pacemaker, Artificial / Q000592:standards*; D012756:Sheep; D016896:Treatment Outcome
keywords: Animal experiments; Human; Leadless pacing; Pacemaker; Subcutaneous ICD