Author + information
- Received November 14, 2018
- Revision received January 10, 2019
- Accepted January 17, 2019
- Published online June 17, 2019.
- Daniel Keene, MBChBa,b,∗ (, )
- Matthew J. Shun-Shin, BMBCha,b,
- Ahran D. Arnold, MBBSa,b,
- James P. Howard, MBBChira,b,
- David Lefroy, MBBChira,
- D. Wyn Davies, MBBS, MDa,
- Phang Boon Lim, MBBChir, PhDa,b,
- Fu Siong Ng, MBBS, PhDa,b,
- Michael Koa-Wing, MBBS, PhDa,b,
- Norman A. Qureshi, MBBS, PhDa,b,
- Nick W.F. Linton, MBBS, PhDa,b,
- Jaymin S. Shah, MBBS, MD(Res)a,
- Nicholas S. Peters, MBBS, MDa,b,
- Prapa Kanagaratnam, MBBChir, PhDa,b,
- Darrel P. Francis, MBBChir, MDa,b and
- Zachary I. Whinnett, BM, BS, PhDa,b
- aDepartment of Cardiology, Imperial College Hospitals National Health Service Trust, London, United Kingdom
- bNational Heart and Lung Institute, Imperial College London, London, United Kingdom
- ↵∗Address for correspondence:
Dr. Daniel Keene, National Heart and Lung Institute, Hammersmith Hospital, DuCane Road, London W12 0HS, United Kingdom.
Objectives This study sought to test specialized processing of laser Doppler signals for discriminating ventricular fibrillation (VF) from common causes of inappropriate therapies.
Background Inappropriate implantable cardioverter-defibrillator (ICD) therapies remain a clinically important problem associated with morbidity and mortality. Tissue perfusion biomarkers, implemented to assist automated diagnosis of VF, sometimes mistake artifacts and random noise for perfusion, which could lead to shocks being inappropriately withheld.
Methods The study tested a novel processing algorithm that combines electrogram data and laser Doppler perfusion monitoring as a method for assessing circulatory status. Fifty patients undergoing VF induction during ICD implantation were recruited. Noninvasive laser Doppler and continuous electrograms were recorded during both sinus rhythm and VF. Two additional scenarios that might have led to inappropriate shocks were simulated for each patient: ventricular lead fracture and T-wave oversensing. The laser Doppler was analyzed using 3 methods for reducing noise: 1) running mean; 2) oscillatory height; and 3) a novel quantification of electromechanical coupling which gates laser Doppler relative to electrograms. In addition, the algorithm was tested during exercise-induced sinus tachycardia.
Results Only the electromechanical coupling algorithm found a clear perfusion cut off between sinus rhythm and VF (sensitivity and specificity of 100%). Sensitivity and specificity remained at 100% during simulated lead fracture and electrogram oversensing. (Area under the curve running mean: 0.91; oscillatory height: 0.86; electromechanical coupling: 1.00). Sinus tachycardia did not cause false positive results.
Conclusions Quantifying the coupling between electrical and perfusion signals increases reliability of discrimination between VF and artifacts that ICDs may interpret as VF. Incorporating such methods into future ICDs may safely permit reductions of inappropriate shocks.
- arrhythmia discrimination
- hemodynamic monitoring
- implantable cardioverter-defibrillator
- inappropriate therapy
- laser Doppler perfusion monitoring
Supported by British Heart Foundation grant FS/15/53/31615 and the Imperial Health Charity. The authors have reported that they have no relationships relevant to the contents 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 November 14, 2018.
- Revision received January 10, 2019.
- Accepted January 17, 2019.