Ventricular fibrillation induced by transesophageal atrial pacing in hypertrophic cardiomyopathy
S Favale1, M Di Biase, U Rizzo
1Division of Cardiology, University of Bari, Italy.
European Heart Journal
|August 1, 1987
Summary
Sudden death in hypertrophic cardiomyopathy may stem from atrial tachyarrhythmias triggering ventricular fibrillation. Electrophysiological properties of the myocardium appear crucial, not just high heart rates.
Area of Science:
- Cardiology
- Electrophysiology
- Genetics
Background:
- Hypertrophic cardiomyopathy (HCM) is a genetic heart condition associated with a high risk of sudden cardiac death.
- The precise mechanisms underlying sudden death in HCM remain incompletely understood.
- Family history of HCM and sudden death is a significant risk factor.
Observation:
- An 18-year-old patient with a family history of HCM and sudden death experienced inducible ventricular fibrillation (VF).
- VF was repeatedly induced via transesophageal atrial stimulation with 1:1 atrioventricular (AV) conduction at a rapid ventricular rate (200 beats/min).
- Pharmacological depression of the AV node successfully prevented VF induction.
Findings:
- The induction of VF occurred at a ventricular rate not considered exceptionally high.
- This suggests that the intrinsic electrophysiological properties of the hypertrophic myocardium play a critical role in facilitating VF.
- Atrial tachyarrhythmias may precipitate life-threatening ventricular arrhythmias in HCM patients.
Implications:
- Understanding the electrophysiological basis of VF in HCM is vital for risk stratification.
- Targeting AV node conduction could be a potential therapeutic strategy to prevent sudden death.
- Further research into the role of atrial tachyarrhythmias in HCM-related sudden cardiac death is warranted.
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