Arrhythmias & electrophysiologyCohort study
Defibrillation Testing During Implantation of Subcutaneous Implantable Cardioverter Defibrillators
- Prospective cohort study
- nationwide
- observational
- propensity score-weighted
- centrally adjudicated endpoints
Defibrillation testing (DT) use decreased from 85.4% (2012-2014) to 66.9% in 2019 (P < 0.001)
Authors' conclusion
Our findings suggest that DT can be safely omitted in the majority of S-ICD recipients, whereas selective DT may be considered in higher-risk subgroups.
Study context
- Population
- All subcutaneous implantable cardioverter defibrillator (S-ICD) recipients in France (2012–2019)
- Participants
- 4,924 recipients
- Exposure
- DT omission vs DT during S-ICD implantation
- Outcome
- Overall mortality, CV mortality, SCD, appropriate and inappropriate shocks by DT status
- Follow-up
- 5 years
Main finding
As reported in the abstract
Nontested vs DTHazard ratio (95% CI)P value
overall mortality
1.17(0.86–1.61)
P = 0.313CV mortality
1.04(0.70–1.56)
P = 0.846SCD
0.27(0.04–1.72)
P = 0.167appropriate shocks
1.01(0.78–1.30)
P = 0.945inappropriate shocks
0.98(0.78–1.23)
P = 0.865Observational data: associations, not effects.
Further findings
Independent predictors of DT failure
| Comparison | OR (95% CI) | P value | |
|---|---|---|---|
| Elevated shock impedance (≥89 Ω) | 4.60 (2.32–9.66) | P < 0.001 | |
| Obesity (body mass index ≥30 kg/m²) | 2.17 (1.01–4.55) | P = 0.007 | |
| 0.10.31310Odds ratio (log scale) |
Combined ineffective shocks or undetected ventricular arrhythmias
- Similar rates (0.05 vs 0.06 per 100 person-years)
Safety
| Outcome | Values |
|---|---|
| DT-related complications | DT 0.1% · Deaths 2 |
Parts of this Brief are withheld: the automatic checks could not confirm them against the abstract.
Original publication
Defibrillation Testing During Implantation of Subcutaneous Implantable Cardioverter Defibrillators. J Am Coll Cardiol. Published 8 July 2025. doi:10.1016/j.jacc.2025.04.048
Summarised from the published abstract; every number is checked against it