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Updated: Jul 6, 2026
12:45
Benefits of Cardiac Resynchronization Therapy in an Asynchronous Heart Failure Model Induced by Left Bundle Branch Ablation and Rapid Pacing
Published on: December 11, 2017
Decrease of electrical cardiac systole.
International Journal of Cardiology
|April 1, 2008
Summary
This study identifies a potential new cardiac syndrome in a patient with a family history of sudden cardiac death. The patient exhibits unique short PQ and QT intervals, suggesting an unknown variant or a novel condition.
Area of Science:
- Cardiology
- Clinical Electrophysiology
- Genetics
Background:
- A 37-year-old male presented with nocturnal tachycardias and syncopal episodes, with a significant family history of sudden cardiac death.
- The patient's family history includes his father's sudden cardiac death at 55 and an infant brother's sudden death at 22 months.
Observation:
- Electrocardiogram (EKG) revealed short PQ and QT intervals, with specific measurements including RR interval: 0.860s, QT interval: 0.29s, Bazett's Formula: 0.312s, and PQ interval: 0.10-0.11s.
- Initial EKG interpretation suggested Lown-Ganong-Levine's Syndrome, but further analysis showed a short QT interval (QTc-f), differing from the typical presentation.
Findings:
- The patient exhibits an electrocardiographic pattern characterized by a shortened electrical systole and accelerated atrioventricular conduction with premature ventricular repolarization.
- Schwartz scale risk assessment indicated a high risk for sudden cardiac death (4.5/4 points).
Implications:
- This case highlights a potentially unknown variant of Lown-Ganong-Levine's Syndrome or a novel cardiac syndrome.
- Emphasizes the critical need for exhaustive electrocardiographic parameter measurements in diagnosing cardiac pathologies.
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