Acute cardiac care & resuscitationCohort study
Scope and Outcome of Early Repolarization Syndrome in Unexplained Cardiac Arrest: Insights From the National HiRO Registry
- retrospective cohort study
Authors' conclusion
ERS is associated with shorter corrected QT interval intervals and reduced arrhythmia-free survival compared with IVF, with an incidence rate of 3.0 per 100 person-years. These findings underscore the importance of careful ECG review in patients with apparent UCA, to detect ER and undertake individualized risk assessment in affected individuals.
Study context
- Population
- Patients from the CASPER (Cardiac Arrest Survivors with Preserved Ejection Fraction Registry) who survived unexplained cardiac arrest (UCA) and had structurally normal hearts with an Implantable Cardioverter Defibrillatorof 709 patients, after 186 with explanatory diagnoses and no early repolarization (ER) pattern were excluded · early repolarization syndrome (ERS) 48 · idiopathic ventricular fibrillation (IVF) 463 · Dx+ER 12
- Participants
- 523 patients
- Exposure
- long-term outcomes in ERS compared with IVF
- ERSn = 48
- IVFn = 463
- Dx+ERn = 12
- Outcome
- appropriate Implantable Cardioverter Defibrillator therapy
- Follow-up
- Median 5.6 years
Main finding
As reported in the abstract
| Group | Value | incidence rate |
|---|---|---|
| ERS | 23% | 3.0 per 100 person-years |
| IVF | 13% | 1.5 per 100 person-years |
- ERS vs IVF: P = 0.09
Observational data: associations, not effects.
Further findings
ER as predictor of arrhythmia recurrence
| Comparison | odds ratio (95% CI) | P value | |
|---|---|---|---|
| ER · adjusted for age, sex, and ethnicity; independent predictor | 2.59 (1.33–4.85) | P = 0.004 | |
| 0.20.5125Odds ratio (log scale) |
| Outcome | ERS | IVF | Dx+ER | Estimate | P value |
|---|---|---|---|---|---|
| Corrected QT interval · significantly shorter in ERS | 412 ± 25 ms | 431 ± 41 ms | Not reported in the abstract | P < 0.01 | |
| Deaths · no significant difference between groups | P = 0.39 | ||||
| Arrhythmia-free survival · lower in ERS | P = 0.03 |
- Deaths — Four deaths occurred
- 0.8%
- Appropriate Implantable Cardioverter Defibrillator therapies in Dx+ER
- 42%
Original publication
Scope and Outcome of Early Repolarization Syndrome in Unexplained Cardiac Arrest: Insights From the National HiRO Registry. Circ Arrhythm Electrophysiol. Published 20 May 2026. doi:10.1161/circep.125.014433
Summarised from the published abstract; every number is checked against it