Author + information
- Received July 19, 2018
- Revision received October 11, 2018
- Accepted November 1, 2018
- Published online February 18, 2019.
- Lucas V.A. Boersma, MD, PhDa,b,∗ (, )
- Béla Merkely, MD, PhDc,
- Petr Neuzil, MD, PhDd,
- Ian G. Crozier, MDe,
- Devender N. Akula, MDf,
- Liesbeth Timmers, MDg,
- Zbigniew Kalarus, MD, PhDh,i,
- Lou Sherfesee, PhDj,
- Paul J. DeGroot, MSj,
- Amy E. Thompson, MS, MBAj,
- Daniel R. Lexcen, PhDj and
- Bradley P. Knight, MDk
- aDepartment of Cardiology, St. Antonius Hospital, Nieuwegein, the Netherlands
- bAcademic Medical Center (AMC), University of Amsterdam, Amsterdam, the Netherlands
- cSemmelweis University, Heart and Vascular Center, Budapest, Hungary
- dDepartment of Cardiology, Na Homolce Hospital, Prague, Czech Republic
- eDepartment of Cardiology, Christchurch Hospital, Christchurch, New Zealand
- fLourdes Cardiology Center, Voorhees, New Jersey
- gDepartment of Cardiology, Ghent University Hospital, Ghent, Belgium
- hSMDZ, Zabrze, Poland, Medical University of Silesia, Katowice, Poland
- iDepartment of Cardiology, Silesian Center for Heart Diseases, Zabrze, Poland
- jMedtronic, Minneapolis, Minnesota
- kNorthwestern University, Feinberg School of Medicine, Chicago, Illinois
- ↵∗Address for correspondence:
Dr. Lucas V. A Boersma, Department of Cardiology, St. Antonius Hospital, PO 2500, 3430 EM, Nieuwegein, the Netherlands.
Objectives The ASD2 (Acute Extravascular Defibrillation, Pacing, and Electrogram) study evaluated the ability to adequately sense, pace, and defibrillate patients with a novel implantable cardioverter-defibrillator (ICD) lead implanted in the substernal space.
Background Subcutaneous ICDs are an alternative to a transvenous defibrillator system when transvenous implantation is not possible or desired. An alternative extravascular system placing a lead under the sternum has the potential to reduce defibrillation energy and the ability to deliver pacing therapies.
Methods An investigational lead was inserted into the substernal space via a minimally invasive subxiphoid access, and a cutaneous defibrillation patch or subcutaneous active can emulator was placed on the left mid-axillary line. Pacing thresholds and extracardiac stimulation were evaluated. Up to 2 episodes of ventricular fibrillation were induced to test defibrillation efficacy.
Results The substernal lead was implanted in 79 patients, with a median implantation time of 12.0 ± 9.0 min. Ventricular pacing was successful in at least 1 vector in 76 of 78 patients (97.4%), and 72 of 78 (92.3%) patients had capture in ≥1 vector with no extracardiac stimulation. A 30-J shock successfully terminated 104 of 128 episodes (81.3%) of ventricular fibrillation in 69 patients. There were 7 adverse events in 6 patients causally (n = 5) or possibly (n = 2) related to the ASD2 procedure.
Conclusions The ASD2 study demonstrated the ability to pace, sense, and defibrillate using a lead designed specifically for the substernal space.
- anterior mediastinum
- defibrillation lead
- implantable cardioverter-defibrillator
This study was sponsored in its entirety by Medtronic. Dr. Boersma is a consultant with Boston Scientific Corp., Medtronic, and Abbott; has received research grants from Medtronic; and has received fellowship support from Boston Scientific Corp. Dr. Merkely has received lecture fees from Medtronic, Biotronik, and Abbott. Dr. Neuzil has been a consultant for and is a member of the advisory board for Medtronic. Dr. Crozier has been a consultant for and has received research grants and fellowship support from Medtronic. Ms. Thompson holds stock in Medtronic. Dr. Knight has been a consultant for and has received lecture fees and fellowship support from Medtronic. All other authors have reported that they have no relationships relevant to the content of this paper to disclose.
All authors attest they are in compliance with human studies committees and animal welfare regulations of the authors’ institutions and Food and Drug Administration guidelines, including patient consent where appropriate. For more information, visit the JACC: Clinical Electrophysiology author instructions page.
- Received July 19, 2018.
- Revision received October 11, 2018.
- Accepted November 1, 2018.
- 2019 The Authors