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A pause for thought: exercise-induced sinus arrest causing syncope in a young male.
John Whitaker1, Matthew Wright, Mark O'Neill
1Department of Cardiology, St Thomas' Hospital, London, UK. john.whitaker@trinity-oxford.com
BMJ Case Reports
|June 16, 2012
Summary
This case study highlights exercise-induced vasovagal syncope in a young man with a structurally normal heart. It emphasizes the rarity of this condition and the empirical nature of treatment for vasovagal asystole.
Area of Science:
- Cardiology
- Exercise Physiology
Background:
- Syncope, or fainting, can occur after exercise, particularly in young, healthy males.
- Vasovagal syncope is a common cause of fainting, typically triggered by emotional stress or pain, but less commonly reported post-exercise.
Observation:
- A 32-year-old man experienced recurrent syncope immediately after exercise.
- During a Bruce protocol exercise test, he lost consciousness during recovery, exhibiting sinus arrest and junctional ectopy on ECG.
- His heart rhythm spontaneously reverted to sinus rhythm, and consciousness was regained.
Findings:
- The patient had a structurally normal heart, with normal ECG and echocardiogram findings.
- The syncope was attributed to vasovagal asystole triggered by exercise, a rare presentation.
- The episode involved significant sinus pauses and subsequent junctional rhythm.
Implications:
- This case underscores the possibility of exercise-induced vasovagal syncope even in individuals with no underlying structural heart disease.
- Management strategies for exercise-related vasovagal asystole require individualized, empirical approaches.
- Further research may elucidate specific triggers and refine treatment protocols for this uncommon condition.
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