Preexcitation unmasks J waves: 2 cases.
Satomi Nagao1, Yuka Hayashi, Nobue Yagihara
1Division of Cardiology, Niigata University Graduate School of Medical and Dental Science, Niigata, Japan.
Journal of Electrocardiology
|December 7, 2010
Summary
J waves of early repolarization can be influenced by the depolarization process. In two cases of Wolff-Parkinson-White syndrome, J waves were unmasked by preexcitation and disappeared after ablation.
Area of Science:
- Cardiology
- Electrophysiology
Background:
- J waves of early repolarization are a poorly understood electrocardiographic phenomenon.
- The relationship between J waves and the cardiac depolarization process, particularly preexcitation, remains unclear.
Observation:
- Two cases of Wolff-Parkinson-White syndrome (a condition involving cardiac preexcitation) are presented.
- In both patients, electrocardiograms revealed J waves that were associated with delta waves (indicating preexcitation).
Findings:
- J waves were unmasked by preexcitation in patients with Wolff-Parkinson-White syndrome.
- Following successful radiofrequency catheter ablation to eliminate preexcitation, the J waves disappeared in both cases.
- While J waves resolved, ST elevation persisted in precordial leads in one patient post-ablation.
Implications:
- These findings suggest that J waves may be influenced or even caused by the cardiac depolarization process, specifically preexcitation.
- This observation provides new insights into the pathophysiology of J waves and their potential relationship with arrhythmogenic substrates.
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