Unexpected Cardiac Asystole Caused by Vasovagal Reaction During Venipuncture: A Case Report

The vasovagal reaction can lead to benign, self-limiting syncope triggered by stimuli such as pain or emotional stress. However, in rare and severe cases it may result in cardiac asystole. Previous episodes of vasovagal reactions could be a risk factor for cardiac asystole.

We present a 39-year-old male with a previous episode of vasovagal syncope who developed an unexpected 15-second episode of asystole during venipuncture, for which we performed immediate chest compressions. Further evaluations revealed no apparent underlying cause. The patient was subsequently diagnosed with transient asystole secondary to vasovagal reaction.

While venipuncture is a common procedure in clinical practice, clinicians should be aware of the potential risk for cardiac asystole. Detailed medical history of previous episodes of vasovagal reactions could be helpful.