Characteristics Of The Carotid Atherosclerotic Plaque

A major cause for the occurrence of stroke or TIA is atherosclerosis. Currently, the degree of the carotid artery stenosis is an important factor to select patients for a carotid endarterectomy (CEA). New imaging techniques such as MDCTA and MRI have made it possible to look in detail at the atherosclerotic plaque. This allows us to see which components (for example hemorrhage, calcifications, lipid core) are present in the atherosclerotic plaque. The exact plaque composition could help to determine which people have a higher risk of getting a recurrent stroke and could have an important impact on the choice of treatment. The PARISK study aims to answer the question which plaque characteristics – assessed with ultrasound, MDCTA and MRI – are associated with an increased risk of recurrent stroke. At this moment, final follow-up measurements are performed to answer this question. For now, we tried to get a better understanding of what happens in an atherosclerotic plaque and the role of blood clotting in atherosclerosis. Moreover, we looked at which imaging techniques and which plaque characteristics can be valuable in future clinical practice.

A few examples of the topics discussed in this thesis:
1. Von Willebrand Factor (VWF) and ADAMTS13 are involved in blood clotting and previous research has shown that these blood biomarkers are also associated with an increased risk of cardiovascular disease. Atherosclerosis may play a role in this association. We investigated whether we could prove this hypothesis, unfortunately the precise mechanism of the relationship between VWF and ADAMTS13 and the risk of cardiovascular disease remains unknown.
2. In the PARISK study various imaging techniques to image the carotid artery are used. We have found a link between the presence of hemorrhage in the atherosclerotic plaque on MRI and plaque ulceration on MDCTA. In addition, we found that MRI plaque imaging techniques presently cannot be recommended to estimate volume of plaque calcifications in individual patients, and that giving a contrast medium in ultrasound can have additional value to assess plaque ulcerations.