Arrhythmias & electrophysiology
Assessment of activation delay in the right ventricular outflow tract as a potential complementary diagnostic tool for Brugada Syndrome
Authors' conclusion
In BrS, the delay in RVOT activation can be identified using a threshold value of 45% above the mean activation time in the anterior-RV for each patient, offering a reliable diagnostic tool when standard ECG method alone falls short.
Study context
- Population
- Patients with Brugada syndrome and controls undergoing ajmaline infusion and electrocardiographic (ECG) imagingPhase 1 cohort
- Participants
- 57 vs 10
- Comparison
- Electrocardiographic imaging (ECGi) right ventricular outflow tract (RVOT) activation delay threshold in Brugada syndrome (BrS) vs controls
- BrSn = 57
- Controlsn = 10reference
- Outcome
- Diagnostic threshold for BrS from RVOT vs anterior-RV mean activation time on ECGi
Methodological detailstwo-phase: cut-off determination and blinded validation
- Two-phase: cut-off determination and blinded validation
Performance
As reported in the abstract
45% increase in anterior-RV ATm as predictor of delayed RVOT activation (Phase 1)
AUC
0.97
Accuracy
0.92
F-score
0.95
Further findings
| Outcome | BrS | Controls | |
|---|---|---|---|
| Blinded validation (Phase 2) | |||
| Increase <45% | Not reported in the abstract | 7 out of 7 | BrS: not reported in the abstract |
- Blinded validation (Phase 2): Pattern-concealed 11 out of 20 events · accuracy 67%
- Blinded validation (Phase 2): Pattern-positive 19 out of 20 events · accuracy 96%
RVOT activation time (ATm), controls vs BrS (concealed; manifested Pattern 1) (Phase 1)
- Controls vs concealed BrS
- 3 721 ± 6.23 vs. 68.33 ± 14.73 ms, P < 0.001
- Controls vs manifested BrS
- 37.21 ± 6.23 vs. 107.57 ± 21.16 ms, P < 0.001
Right bundle branch block (RBBB) patients
- ATm delay cut-off reached only with concomitant BrS
Original publication
Assessment of activation delay in the right ventricular outflow tract as a potential complementary diagnostic tool for Brugada Syndrome. Europace. Published 13 June 2025. doi:10.
Summarised from the published abstract; every number is checked against it