Von Willebrand factor (VWF) as a determinant of silent cerebral microbleeds during TAVR in a prospective MRI cohort - 06/01/20
Résumé |
Background |
Cerebral microbleeds have been observed in “asymptomatic” elderly patients undergoing systematic MRIs and might be related with cognitive decline. A defect in Von Willebrand factor (VWF) after Trans Aortic-valve Replacement (TAVR) enhanced bleeding risk and possibly contributes to vascular malformations.
Aim |
To define the occurrence of “acute” microbleeds during TAVR and the clinical and procedural factors associated with this occurrence including a post-procedural defect in VWF.
Methods |
A prospective cohort of patients with aortic stenosis referred for TAVR was included. A standardized neurological assessment, a cerebral magnetic resonance imaging (MRI) and a biological analysis including quantification of VWF multimers and PFA-CADP were performed before and after TAVR.
Results |
Eighty-four patients completed the imaging protocol. On pre-procedural MRI, 22 patients (26%, 95%CI=17–37%) had at least one microbleeds. After TAVR, new microbleeds were observed in 19 (23%, 95%CI=14–33%) patients. The occurrence of new microbleeds was independent of the presence microbleeds at baseline. A lower HMW-multimer-ratio as measured immediately at the end of the procedure was associated with the occurrence of new microbleed detected on the MRI performed 3 days after the procedure (0.90±0.14 vs. 1.06±0.27, P=0.009). The same observation was made with a higher CT-ADP (165±72 vs. 127±57, P=0.02). A prolonged procedure (RR=1.21 [1.01–1.170] for every 5min of fluoroscopy time, P=0.04) and post-procedural acquired-VWF-defect (RR=1.42 [1.08–1.89] for every lower “0.1 unit” of HMW-multimer-ratio, P=0.004) were the only factors associated with the occurrence of new post-procedural microbleed(s).
Conclusions |
We report for the first time a high incidence (23%, 95%CI=14–33%) of new post-procedural cerebral microbleeds occurring during TAVR. Procedural management and persistence of acquired-VWF defect could play a major role in the occurrence of those new microbleeds.
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Vol 12 - N° 1
P. 76 - janvier 2020 Retour au numéroBienvenue sur EM-consulte, la référence des professionnels de santé.