Common carotid artery peak systolic velocity ratio predicts high-grade common carotid stenosis Presented as a Podium presentation at the Forty-third Annual Symposium of the Society for Clinical Vascular Surgery, Miami, Fla, March 29-April 2, 2015.

Abstract

Objective Screening for common carotid artery (CCA) stenosis with duplex ultrasound (DUS) velocity criteria alone can be limited by within-patient and between-patients hemodynamic variability. This study aimed to evaluate inter-CCA velocity ratio criteria to predict high-grade CCA stenosis. Methods This was a retrospective review of consecutive patients who underwent computed tomography angiography and DUS peak systolic velocity (PSV) measurements of bilateral CCAs, independently recorded, between 2008 and 2014. Patients with dampened CCA waveforms on DUS composed group B. The remainder without dampened waveforms constituted group A. Inter-CCA PSV ratios were calculated by dividing the higher CCA PSV by the lower one of the other side, so the ratios would always be a 1. Ratios were subsequently paired with each respective unilateral CCA diameter stenosis and differential bilateral CCA diameter stenosis. A quadratic regression model was fitted to predict unilateral and differential stenosis. Receiver operating characteristic curve was used to determine optimal ratios for a 50% and a 80% CCA stenosis. The study excluded patients with carotid artery occlusion. Results From a total of 201 patients, 193 patients were included in group A and 8 in group B. Within group A, 31 patients had a 50% unilateral stenosis and 17 had a 50% differential stenosis. All stenoses a 50% were identified on the same side with the higher PSV. Inter-CCA PSV ratio predicted a 50% unilateral (r2 = 0.536; P