Elsevier

Heart Rhythm

Volume 16, Issue 9, September 2019, Pages 1429-1435
Heart Rhythm

Clinical
Devices
Algorithm-based reduction of inappropriate defibrillator shock: Results of the Inappropriate Shock Reduction wIth PARAD+ Rhythm DiScrimination–Implantable Cardioverter Defibrillator Study

https://doi.org/10.1016/j.hrthm.2019.03.016Get rights and content
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open access

Background

Inappropriate shocks (IS) continue to have a major negative impact on patients implanted with defibrillators.

Objective

The purpose of this study was to assess IS reduction with the PARAD+ discrimination algorithm in a general population implanted for primary or secondary prevention.

Methods

ISIS-ICD (Inappropriate Shock Reduction wIth PARAD+ Rhythm DiScrimination–Implantable Cardioverter Defibrillator) was a 2-year international, interventional study in patients implanted with a dual implantable cardioverter-defibrillator (ICD) or triple-chamber defibrillator (cardiac resynchronization therapy–defibrillator [CRT-D]) featuring PARAD+. IS (shocks not delivered for ventricular tachycardia or fibrillation) were independently adjudicated. The primary endpoint was percentage of IS-free patients at 24 months. Primary and worst-case analyses of annual incidence rates of patients with ≥1 IS, overall and per defibrillator type, were conducted.

Results

In total, 1013 patients (80.7% male; age 67.1 ± 11.4 years; 68%/30%/2% primary/secondary/other indication) were enrolled and followed for a median of 552 days (interquartile range 354; 725). Of 993 analyzed patients programmed with PARAD+, 14 had ≥1 IS, corresponding to a percentage free from IS of 98.1% (95% confidence interval [CI] 96.8%– 98.9%). Annual incidence rates (per 100 person-years) of patients with IS were 1.0 (95% CI 0.59–1.69) and 2.1 (95% CI 1.46–3.02) in the primary and worst-case analyses, respectively. In ICD patients, rates were 1.2 (95% CI 0.68–2.23) and 2.3 (95% CI 1.47–3.53), and in CRT-D patients 0.59 (95% CI 0.19–1.83) and 1.8 (95% CI 0.93–3.44) per 100 person-years.

Conclusion

The annual rate of defibrillator patients with IS using the enhanced PARAD+ discrimination algorithm alone ranged from 1.0 to 2.1 per 100 person-years in a general population implanted for primary or secondary prevention.

Keywords

Defibrillation
Discrimination algorithm
Shock
Ventricular fibrillation
Ventricular tachyarrhythmia

Cited by (0)

The ISIS-ICD study was supported by MicroPort CRM, Clamart, France. Dr Ruiz-Granell has received lecture honorary/travel support from Abbot, Biotronik, and MicroPort CRM; is a consultant for Boston Scientific and Medtronic; and performs/has performed clinical studies supported by Biotronik, Boston Scientific, Medtronic, and MicroPort CRM. Dr Dompnier is a consultant for MicroPort CRM. Dr Khalighi is a supervising physician trainer. Dr García-Campo has received lecture honorary/travel support from Medtronic, Abbott, Biotronik, and MicroPort CRM; and performs/has performed clinical studies supported by Medtronic, Abbott, Biotronik, Boston, and MicroPort CRM. Dr Ritter has received an educational grant from Medtronic. A. Olivier and A. Barcelo are employees of, and receive a salary from, MicroPort CRM. ClinicalTrials.gov Identifier: NCT01410552.