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NEJM Study: Point-of-Care Hemostasis Test Detects Aortic Regurgitation During TAVR in Real Time

In 183 TAVR patients, restoration of high-molecular-weight von Willebrand factor multimers tracked successful correction of aortic regurgitation after balloon dilation. A point-of-care closure time (CT-ADP) above 180 seconds identified residual regurgitation with 92% sensitivity, 92% specificity, and 99% negative predictive value, validated in a second 201-patient cohort. Both markers independently predicted one-year mortality.

The original study

Von Willebrand Factor Multimers during Transcatheter Aortic-Valve Replacement.

Authors
Van Belle E, Rauch A, Vincent F, Robin E, Kibler M, Labreuche J, et al.
Journal
The New England journal of medicine
Type
Journal Article, Research Support, Non-U.S. Gov't, Validation Study, Observational Study
PMID
27464202
Read the original study →

Original abstract

BACKGROUND: Postprocedural aortic regurgitation occurs in 10 to 20% of patients undergoing transcatheter aortic-valve replacement (TAVR) for aortic stenosis. We hypothesized that assessment of defects in high-molecular-weight (HMW) multimers of von Willebrand factor or point-of-care assessment of hemostasis could be used to monitor aortic regurgitation during TAVR. METHODS: We enrolled 183 patients undergoing TAVR. Patients with aortic regurgitation after the initial implantation, as identified by means of transesophageal echocardiography, underwent additional balloon dilation to correct aortic regurgitation. HMW multimers and the closure time with adenosine diphosphate (CT-ADP), a point-of-care measure of hemostasis, were assessed at baseline and 5 minutes after each step of the procedure. Mortality was evaluated at 1 year. A second cohort (201 patients) was studied to validate the use of CT-ADP in order to identify patients with aortic regurgitation. RESULTS: After the initial implantation, HMW multimers normalized in patients without aortic regurgitation (137 patients). Among the 46 patients with aortic regurgitation, normalization occurred in 20 patients in whom additional balloon dilation was successful but did not occur in the 26 patients with persistent aortic regurgitation. A similar sequence of changes was observed with CT-ADP. A CT-ADP value of more than 180 seconds had sensitivity, specificity, and negative predictive value of 92.3%, 92.4%, and 98.6%, respectively, for aortic regurgitation, with similar results in the validation cohort. Multivariable analyses showed that the values for HMW multimers and CT-ADP at the end of TAVR were each associated with mortality at 1 year. CONCLUSIONS: The presence of HMW-multimer defects and a high value for a point-of-care hemostatic test, the CT-ADP, were each predictive of the presence of aortic regurgitation after TAVR and were associated with higher mortality 1 year after the procedure. (Funded by Lille 2 University and others; ClinicalTrials.gov number, NCT02628509.).