Von Willebrand Factor Point-of-care Testing to Improve Minimally Invasive TAVI Outcomes

Paravalvular regurgitation (PVR) is an important complication of Transcatheter Aortic Valve Implantation (TAVI) that is associated with a 2.5-fold increase risk of mortality. Transesophageal echocardiographic (TEE) is considered as the gold standard to assess the severity of PVR and guide the physician to perform corrective procedures during TAVI, but it requires general anesthesia (GA). With such approach (TEE+GA), the PARTNERII trial has demonstrated that very low rate of PVR (3,5%) can be achieved with current devices. Registries have demonstrated a strong trend for using a mini-invasive approach in which the procedure is performed under conscious sedation (CS) without TEE. However, several studies raised concerns on the safety of this mini-invasive approach concerning the PVR rate. Thus, the accurate and real-time assessment of the presence and severity of PVR is an unmet clinical need to optimize TAVI without TEE guidance. A recent study reported that a blood biomarker reflecting the Von Willebrand factor (VWF) activity, i.e. the closure time with adenosine diphosphate (CT-ADP), is a valuable non-invasive, highly reproducible, and easy to perform alternative to TEE for PVR evaluation.

The hypothesis is that the measurement of CT-ADP during TAVI performed without TEE guidance can improve both the detection of significant PVR and thus the procedural and clinical outcomes (primary objective).