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

Point-of-care Haemostasis Testing of Von Willebrand Factor Function Embedded in Catheterization Laboratory to Improve Real-time Management of Paravalvular Regurgitation During Minimally Invasive TAVI

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).

Inclusion Criteria:

• All patients scheduled to undergo mini-invasive TAVI at any of the participating centers and fulfilling the inclusion criteria will be eligible for entry in the study. The decision to undertake TAVI will be made by the local heart team.
• Symptomatic aortic stenosis scheduled to undergo TAVI
• TAVI performed via mini-invasive approach defined as: transfemoral access route; local anesthesia/conscious sedation; no TEE guidance.
• All types of prosthetic valves (balloon-expandable, self-expandable, others) are accepted

Exclusion Criteria:

• TAVI through non-transfemoral approach
• TAVI with concomitant percutaneous coronary intervention
• TAVI performed under general anesthesia
• TAVI performed under TEE guidance
• Valve-in-valve procedure
• Inability to provide informed consent
• Associated ≥ moderate mitral regurgitation
• Peri-procedural treatment with ticagrelor or prasugrel treatment / direct oral anticoagulant