Joint analysis of cardiovascular control and shear wave elastography to assess the vulnerability of carotid artery plaque

Noninvasive characterization of the carotid plaque is important in asymptomatic carotid artery stenosis patients because plaque’s vulnerability contributes to the risk of stroke. This study proposes the joint evaluation of elastographic and cardiovascular control markers for a deeper characterization of plaque vulnerability. Autonomic and baroreflex markers were derived from spontaneous fluctuations of heart period (HP) and systolic arterial pressure (SAP) in 78 patients scheduled for carotid endarterectomy (age: 74.3+7.7 yrs, 30 females) evaluated in supine position (REST) and during active standing (STAND). The Young’s modulus (YM) was computed via shear wave elastography. Thirty-six patients featured vulnerable (VULN) and 42 stable (STABLE) plaque according to post-surgery evaluation. VULN patients had a lower YM and higher baroreflex sensitivity at REST, as estimated from the transfer function gain from SAP to HP in high frequency (HF: 0.15-0.4 Hz) band (TFGHP-SAP(HF)), that decreased during STAND solely in VULN. A multivariate logistic regression model was built using YM and TFGHP-SAP(HF) at REST to predict plaque vulnerability. Compared to the sole YM the addition of TFGHP-SAP(HF) at REST increased the area under the receiver operating characteristic curve from 0.625 to 0.649. Markers of elastography and baroreflex could be fruitfully combined to assess carotid plaque vulnerability.