Prospective, Multicenter, Randomized Controlled Clinical Study Evaluating the VitaFlow Liberty® Flex Transcatheter Aortic Valve Delivery System for the Treatment of Severe Aortic Stenosis Lesions

Trial details

Who runs it

Shanghai Zhongshan Hospital

Trial code

NCT07145463

Record updated

28 August 2025

Original description

This is a prospective, multicenter, randomized controlled clinical study designed to evaluate the real-world performance of the VitaFlow Liberty® Flex Transcatheter Aortic Valve Retrievable and Steerable Delivery System (Investigational Device) for treating severe aortic stenosis (AS) in challenging anatomies. The study will compare it against the VitaFlow Liberty® Retrievable Delivery System (Control Device), which lacks steerability.Read full original descriptionShow less

A Prospective, Multicenter, Randomized Controlled Clinical Study Evaluating the VitaFlow Liberty® Flex Transcatheter Aortic Valve Retrievable and Steerable Delivery System for the Treatment of Severe Aortic Stenosis

This is a prospective, multicenter, randomized controlled clinical study designed to evaluate the real-world performance of the VitaFlow Liberty® Flex Transcatheter Aortic Valve Retrievable and Steerable Delivery System (Investigational Device) for treating severe aortic stenosis (AS) in challenging anatomies. The study will compare it against the VitaFlow Liberty® Retrievable Delivery System (Control Device), which lacks steerability.

Key Study Elements:

Objective: The primary objective is to assess the device's performance using the incidence of a composite endpoint before hospital discharge. This endpoint includes permanent pacemaker implantation (PPI), valve-in-valve (ViV) implantation, or moderate-to-severe paravalvular leakage (PVL).

Design: A prospective, multicenter RCT with 1:1 randomization (Experimental: VitaFlow Liberty® Flex vs. Control: VitaFlow Liberty®). Approximately 15 sites in China will participate. Subjects undergo follow-up at discharge, 30 days, and 1 year post-procedure. An independent data center handles management and analysis.

Population: Patients with severe AS (echo confirmed: peak velocity ≥4.0 m/s, mean gradient ≥40 mmHg, or AVA ≤1.0 cm²/AVAi ≤0.6 cm²/m²) AND preoperative CTA showing a challenging aortic-left ventricular angle >60°. NYHA class ≥II is required.

Devices:

Investigational: VitaFlow Liberty® Flex (Retrievable \& Steerable Delivery System - Models DSRS21/24/27/30/A series; Loading Tools LT-S series).

Control: VitaFlow Liberty® (Retrievable Delivery System - Models DSR21/24/27/30; Loading Tools LT series).

Endpoints:

Primary: Composite of PPI, ViV, or moderate-to-severe PVL before discharge.

Secondary: Include individual components of the primary endpoint (ViV, PVL) immediately post-procedure, procedural success (VARC-3), technical assistance rates, valve retrievals, implantation depth, arch/valve crossing performance, valve hemodynamics (gradient, area, leak, LVEF), NYHA class, Major Adverse Cardiac and Cerebrovascular Events (MACCE - all-cause death, MI, stroke, reoperation), major vascular complications (at discharge/30 days).

Key Inclusion: Severe AS, challenging anatomy (aortic-LV angle >60°), NYHA ≥II, informed consent.

Key Exclusions: Device/contrast allergies, anticoagulant intolerance, active infection, severe vascular disease prohibiting access, ascending aorta ≥55mm, unsuitable aortic root anatomy, intracardiac mass/thrombus, recent MI (<30 days), severe concomitant mitral/tricuspid regurgitation, cardiogenic shock, severe LV dysfunction (LVEF<20%), hematologic abnormalities, pregnancy/breastfeeding, participation in other device trials.

Visits: Screening (≤30d pre-op), Procedure (intra-op to 24h post-op), Discharge (≤7d post-op), 30d Follow-up (±7d), 12m Telephone FU (±1m).

Sample Size: Planned enrollment of 232 subjects (116 per group), calculated for superiority testing. Based on an expected composite endpoint rate of 21% for the Flex system vs. a historical rate of 38% for non-steerable systems (Superiority margin Δ1=0%, one-sided α=2.5%, Power=80%, accounting for 5% dropout).

Purpose: This study aims to demonstrate the superiority of the retrievable and steerable VitaFlow Liberty® Flex delivery system in reducing the composite rate of key adverse events (PPI, ViV, significant PVL) at discharge compared to the non-steerable system, specifically in patients with severe AS and anatomically challenging aortic-left ventricular angles.

Inclusion: Diagnosis of severe aortic stenosis, defined as: echocardiographically confirmed peak aortic valve velocity ≥4.0 m/s, or mean aortic valve gradient ≥40 mmHg, or aortic valve area (AVA) ≤1.0 cm2 (or AVA index ≤0.6 cm2/m2); Preoperative cardiac and great vessel CT angiography (CTA) with 3D reconstruction demonstrating an aortic-left ventricular angle >60°, indicating potential challenges for arch crossing and valve crossing; New York Heart Association (NYHA) functional class ≥II; Voluntary participation in the study with signed informed consent.

Exclusion: Acute myocardial infarction within 30 days prior to procedure (defined as Q-wave MI or non-Q-wave MI); Concomitant severe mitral or tricuspid regurgitation; Concomitant cardiogenic shock or hemodynamic instability requiring inotropic support, mechanical ventilation, or mechanical cardiac assistance; Known allergy or intolerance to components of the investigational or control devices (e.g., nitinol) or contrast agents; Contraindication or known allergy to anticoagulant or antiplatelet therapy, rendering the patient unable to tolerate such treatment; Known active infective endocarditis or other active infections; Known severe vascular disease that would preclude safe prosthetic valve implantation; Subjects currently participating in or planning to participate in other drug or device clinical studies within 12 months postoperatively; Any other condition that the investigator or heart team deems may hinder the subject's safe participation in the study; Concomitant severe left ventricular dysfunction (defined as left ventricular ejection fraction LVEF<20%); Concomitant hematologic abnormalities defined as leukopenia (WBC count <3×109/L), thrombocytopenia (platelet count <30×109/L), history of bleeding diathesis or coagulopathy, or hypercoagulable state; Ascending aorta width ≥55mm; Pre-procedural imaging shows aortic root anatomy unsuitable for transcatheter aortic valve implantation (including aortic root calcification that may affect proper valve expansion); Pre-procedural echocardiography shows intracardiac mass, left ventricular or left atrial thrombus, or vegetation; Female subjects known to be pregnant or breastfeeding.

ClinicalTrials.gov NCT07145463