Arrhythmias & electrophysiology
Roles of Atrial Arrhythmias in Triggering Torsade de Pointes in Patients With Acquired Long QT Syndrome
Authors' conclusion
AAs play a key role in triggering TdP in more than half of patients with acute acquired LQTS and can increase TdP frequency after initiating therapy.
Study context
- Population
- Consecutive acute acquired long QT syndrome (LQTS) patients with documented Torsade de Pointes (TdP) (14 men, median age 69 years, median QTc 645.5 ms)
- Participants
- 34 participants · 81 TdP episodes
- Exposure
- AA-induced vs non-AA-induced TdP
- Atrial arrhythmias (AAs)-inducedn = 18
- non-AAs-inducedn = 16reference
- Outcome
- Contribution of AAs to the initiation of TdP
Methodological detailsconsecutive patients
- Consecutive patients
Main finding
As reported in the abstract
AAs as TdP trigger
- Patients with AAs-induced TdP
- 52.9% (18/34)
- TdP preceded by AAs-initiated short-long sequence (SLSs) (patients)
- 41.2% (14/34)
- TdP directly induced by R-on-T AAs (patients)
- 23.5% (8/34)
- TdP episodes triggered by AAs
- 48 (59.3%) of the 81
- SLS-induced TdP episodes with AAs-initiated SLSs
- 67.8% (40/59)
- TdP episodes from R-on-T AAs
- 23.5% (19/81)
Observational data: associations, not effects.
Further findings
TdP after initiating therapy
P = 0.008
Events
| Outcome | AAs-induced | non-AAs-induced | P value |
|---|---|---|---|
| Macroscopic T-wave alternans | 6 | 0 | P = 0.02 |
Original publication
Roles of Atrial Arrhythmias in Triggering Torsade de Pointes in Patients With Acquired Long QT Syndrome. Circ Arrhythm Electrophysiol. Published 5 September 2024. doi:10.
Summarised from the published abstract; every number is checked against it