# A Case of Complete Resolution of Repeated Syncope Attacks After a Right-Sided Carotid Endarterectomy

## TL;DR

A patient with repeated fainting episodes was found to have a blocked right carotid artery, and surgery to clear the blockage stopped the fainting.

## Contribution

This case demonstrates that unilateral carotid artery stenosis can cause syncope and be resolved through endarterectomy.

## Key findings

- Syncope attacks ceased after right-sided carotid endarterectomy.
- Severe stenosis in the right internal carotid artery was identified as the cause.
- No cardiac abnormalities were found despite thorough evaluation.

## Abstract

Syncope is a common clinical entity with variable presentations and often an elusive causal mechanism, even after extensive evaluation. In any case, global cerebral hypoperfusion, resulting from the inability of the circulatory system to maintain blood pressure (BP) at the level necessary to supply blood to the brain efficiently, is the final pathway for syncope. Steno-occlusive carotid artery disease, even if bilateral, does not usually cause syncope. However, the patient presented here had repeated syncope attacks and underwent a thorough examination for suspected cardiac disease, but no abnormality was found. Since there was severe stenosis in the right unilateral internal carotid artery (ICA), but no stenosis in the left ICA or vertebrobasilar artery (VBA), and transient left mild hemiparesis associated with syncope, carotid revascularization surgery for the right ICA was performed, and the repeated syncope attacks completely disappeared after the surgery. The patient's condition improved markedly, and no further episodes of syncope have been reported. We report the relationship between carotid artery stenosis and syncope and discuss its pathomechanism.