Scar formation in the carotid sheath is often identified during carotid endarterectomy (CEA) in patients with previous cardiac surgery, and dissection of the carotid sheath and exposure of the carotid arteries in such patients are difficult. The purpose of the present study was to investigate factors related to scar formation identified during CEA in patients with previous cardiac surgery.
Twenty-three patients with internal carotid artery stenosis (≥ 70%) and previous cardiac surgery underwent CEA. A patient was prospectively defined as having scar formation during CEA when scissors were required throughout dissection of the carotid sheath and exposure of the carotid arteries.
Scar formation was identified during dissection of the carotid sheath in 7 patients (30.4%). In all 7 patients, the side of CEA was identical to the side on which the Swan-Ganz catheter was inserted during cardiac surgery, and the incidence of previous ipsilateral Swan-Ganz catheter insertion was significantly higher in patients with the scar formation (100%) than in those without (31.3%). Seven (58.3%) of 12 patients with a history of ipsilateral Swan-Ganz catheter insertion had scar formation. Two of the 7 patients with scar formation experienced complications after CEA, including one patient with hemiparesis due to artery-to-artery embolism during surgery, and another patient with transient vocal cord paralysis.
A history of Swan-Ganz catheter insertion during previous cardiac surgery is associated with the presence of scar tissue in the ipsilateral carotid sheath and a higher risk of complications during CEA.