New Technologies to Determine Carotid Plaque Vulnerability in Patients With Significant Carotid Plaques

New Technologies to Determine Carotid Plaque Vulnerability in Patients With Significant Carotid Plaques

New Technologies to Determine Carotid Plaque Vulnerability: A Pilot Study to Assess Contrast-Enhanced Ultrasound (CEUS) and Shear Wave Elastography (SWE) in Patients With Significant Carotid Plaques

The researchers are trying to determine if the characterization of "vulnerable" carotid artery plaques can be accomplished with ultrasound-based methods that look for vessels in the plaque and measure the plaque stiffness.

All participants will receive a one time Carotid contrast-enhanced Ultrasound (CEUS) examination that may take 30-60 minutes. Follow up calls will be made to the Participants at 6, 12 ,24 and 36 months to ask about occurrence of major adverse cardiovascular events.

Subjects being seen in the Mayo Clinic Gonda Vascular Center who have a plaque causing a > 70% stenosis will be approached for recruitment to receive an ultrasound examination including duplex imaging, shear wave elastography and contrast-enhanced ultrasound.

Cardiovascular high-risk patients with moderate (50-69% diameter) stenosis carotid plaques from the Mayo Clinic Gonda Vascular Center will be approached for recruitment to receive an ultrasound examination including duplex imaging, shear wave elastography and contrast-enhanced ultrasound.

Subjects will receive a low mechanical index (0.17-0.20) imaging during ultrasound contrast agent intravenous infusion. Real-time cine-loop including longitudinal and transverse images obtained at least 3 seconds before and 5 minutes after the appearance of the contrast effect in the lumen of the carotid artery will be acquired and digitally stored for offline analysis. Also use of a 3D ultrasound transducer to evaluate the feasibility of using US images with contrast to assess the residual diameter of the diseased vessel. Specifically, two 3D acquisitions of each lesion would be obtained after contrast has been injected.

Shear wave elastography will be performed with the General Electric Logiq E9 scanner acquiring images of each plaque in the longitudinal and transverse imaging planes. In each plane 10 measurements will be made and the in-phase/quadrature (IQ) data will be saved for further analysis. The plaque area in the imaging plane will be user-defined to extract the wave velocity values for a ROI analysis.

A standard carotid US examination using Duplex imaging will performed using a linear array transducer to obtain longitudinal and transverse images. All ultrasound measurements will be made by a trained registered vascular technologist. Severity of stenosis of the plaque will be measured based on established protocol and guidelines.

Total number of subjects who completed all of the ultrasound examinations to determine visualization of arterial wall (contrast-enhanced ultrasound, 3-D volume ultrasound) and its mechanical properties (shear wave elastography).

Inclusion Criteria: Subject has carotid plaque with > 50% stenosis Subject is able to understand the study procedure and provide informed consent Exclusion Criteria: Subject is pregnant or breast feeding Subject is unable to provide informed consent Subject has contraindication to the use of the Lumason contrast agent.