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Drug-induced spatial dispersion of repolarization
1Masonic Medical Research Laboratory, 2150 Bleecker Street, Utica, NY 13501-1787, USA. ca@mmrl.edu
Cardiology Journal
|July 25, 2008
Summary
Spatial dispersion of repolarization (SDR) amplifies in long QT and Brugada syndromes, leading to dangerous arrhythmias. Quantifying SDR non-invasively, potentially using T(peak)-T(end) interval, remains a key challenge.
Area of Science:
- Cardiology
- Electrophysiology
- Molecular Cardiology
Background:
- Spatial dispersion of repolarization (SDR) creates ECG voltage gradients, including J and T waves.
- Amplified SDR underlies life-threatening ventricular arrhythmias in inherited/acquired ion channelopathies like long QT, short QT, and Brugada syndromes (BrS).
Purpose of the Study:
- To review the role of SDR in drug-induced arrhythmogenesis in long QT and Brugada syndromes.
- To discuss current challenges and potential methods for non-invasive SDR quantification.
Main Methods:
- Review of existing literature on SDR, ion channelopathies, and drug-induced arrhythmias.
- Analysis of mechanisms underlying SDR amplification in long QT and BrS.
- Evaluation of T(peak)-T(end) interval as an index for SDR and transmural dispersion.
Main Results:
- Drug-induced SDR amplification in long QT syndrome often involves M cell action potential duration (APD) prolongation.
- In BrS, SDR amplification is linked to abbreviated right ventricular epicardial APD.
- The T(peak)-T(end) interval shows promise as an index for SDR and transmural dispersion.
Conclusions:
- SDR plays a critical role in drug-induced arrhythmias in long QT and BrS.
- Non-invasive quantification of SDR is crucial for clinical management.
- The T(peak)-T(end) interval warrants further investigation as a non-invasive SDR marker.
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