Horner syndrome related to ipsilateral carotid wall hematoma after stent placement for the treatment of carotid stenoses.

BACKGROUND AND PURPOSE: We prospectively studied the incidence and natural history of Horner syndrome following stent-supported percutaneous angioplasty of the carotid artery (SPAC). We assessed the hypothesis that postinterventional Horner syndrome is related to ipsilateral carotid wall hematoma.

METHODS: We performed duplex sonography of the carotid arteries and clinical examination in 28 consecutive patients before and 4 hours +/- 2, 24 hours +/- 2, and 7 days +/- 1 after SPAC.

RESULTS: Within 24 hours +/- 2 after SPAC, 11 of the 28 patients developed ipsilateral Horner syndrome. Ten of these 11 patients had a postinterventional sonographic appearance of a carotid wall hematoma, whereas only two of the 17 patients without Horner syndrome had this finding (P <.001). In all patients, both Horner syndrome and carotid wall hematoma had resolved 7 days +/- 1 after SPAC.

CONCLUSION: Horner syndrome appears to be a common yet transient event after SPAC. Although postinterventional Horner syndrome is significantly related to ipsilateral carotid wall hematoma, causality of the procedure-related formation of a carotid wall hematoma and oculosympathetic disturbance remains unproven.