Congenital heart diseaseCohort study
Velocity vector analysis for slowly conducting anatomical isthmuses in patients with tetralogy of Fallot
- single-center retrospective study
- consecutive patients
Authors' conclusion
This novel, reproducible, and easy-to-use LVV-based approach to CV measurement for substrate evaluation in patients with TOF suggests that LVV-CV provides superior discriminative performance compared with manual CV measurements for identifying SCAIs associated with SMVT inducibility. Further studies are warranted to evaluate this approach in larger populations.
Study context
- Population
- Consecutive patients with tetralogy of Fallot (TOF) undergoing right ventricular electroanatomic activation mappingpatients included
- Participants
- 44 patients
- Exposure
- automated Local Activation Time Velocity Vector (LVV) analysis and conventional manual measurements
- Outcome
- inducibility of sustained monomorphic ventricular tachycardia (VT; SMVT)
Main finding
As reported in the abstract
SMVT inducible, overall
23 (52.3%)
SMVT inducible, patients referred for catheter ablation of ventricular tachycardia (VT) (history of clinical VT)
12/14 (85.7%)
SMVT inducible, patients referred for EPS without spontaenous VT
11/30 (36.7%)
Observational data: associations, not effects.
Further findings
Number of classification errors
| Outcome | LVV-CV | manual CV measurements |
|---|---|---|
| Discriminative performance for SMVT inducibility | ||
| AUC | 0.81 | 0.75 |
| sensitivity | 0.96 | 0.57 |
| specificity | 0.71 | 0.81 |
Correlation of LVV-CV with manual measurements
- r
- 0.81
Optimal cutoff value of LVV-CV (Youden index)
- cutoff
- 0.5 m/s
Original publication
Summarised from the published abstract; every number is checked against it