Using a steerable VitaFlow Liberty Flex catheter to deliver transcatheter aortic valves in patients with difficult aortic anatomy

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 study will test whether the steerable VitaFlow Liberty Flex delivery system helps doctors place transcatheter aortic valves more safely in people with severe aortic stenosis and challenging aortic-left ventricular angles (>60°).

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 232 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Shanghai Zhongshan Hospital (Academic / other)
• Locations: 1 site (Shanghai, Shanghai Municipality)
• Trial ID: NCT07145463 on ClinicalTrials.gov

What this trial studies

This is a prospective, multicenter, randomized 1:1 trial comparing the investigational steerable VitaFlow Liberty Flex delivery system with the non-steerable VitaFlow Liberty system in patients with severe aortic stenosis and difficult anatomy. Approximately 15 hospitals in China will enroll eligible patients and randomize them to receive TAVR with either the steerable or control delivery catheter. The primary endpoint is a composite measured before hospital discharge (permanent pacemaker implantation, valve-in-valve implantation, or moderate-to-severe paravalvular leak), with follow-up at discharge, 30 days, and 1 year. The trial is open-label and uses centralized randomization to reflect real-world procedural practice.

Who should consider this trial

Good fit: Ideal candidates are symptomatic patients with severe aortic stenosis (e.g., peak velocity ≥4.0 m/s, mean gradient ≥40 mmHg, or AVA ≤1.0 cm2) who have an aortic-left ventricular angle >60° and are suitable for transfemoral TAVR and follow-up.

Not a fit: Patients without challenging anatomy, those with contraindications to TAVR or contrast/anticoagulation, active infection, or severe vascular disease that precludes safe access are unlikely to benefit from this device comparison.

Why it matters

Potential benefit: If successful, the steerable system could lower rates of pacemaker implantation, valve-in-valve procedures, and significant paravalvular leak in patients with challenging aortic anatomy, improving procedural safety and outcomes.

How similar studies have performed: Steerable catheter concepts and advanced delivery systems have shown promise in observational series for improving device positioning, but randomized data directly comparing steerable versus non-steerable TAVR delivery systems in challenging anatomies are limited.

Eligibility criteria

Inclusion Criteria:

1. 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);
2. 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;
3. New York Heart Association (NYHA) functional class ≥II;
4. Voluntary participation in the study with signed informed consent.

Exclusion Criteria:

1. Known allergy or intolerance to components of the investigational or control devices (e.g., nitinol) or contrast agents;
2. Contraindication or known allergy to anticoagulant or antiplatelet therapy, rendering the patient unable to tolerate such treatment;
3. Known active infective endocarditis or other active infections;
4. Known severe vascular disease that would preclude safe prosthetic valve implantation;
5. Ascending aorta width ≥55mm;
6. Pre-procedural imaging shows aortic root anatomy unsuitable for transcatheter aortic valve implantation (including aortic root calcification that may affect proper valve expansion);
7. Pre-procedural echocardiography shows intracardiac mass, left ventricular or left atrial thrombus, or vegetation;
8. Acute myocardial infarction within 30 days prior to procedure (defined as Q-wave MI or non-Q-wave MI);
9. Concomitant severe mitral or tricuspid regurgitation;
10. Concomitant cardiogenic shock or hemodynamic instability requiring inotropic support, mechanical ventilation, or mechanical cardiac assistance;
11. Concomitant severe left ventricular dysfunction (defined as left ventricular ejection fraction LVEF\<20%);
12. 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;
13. Female subjects known to be pregnant or breastfeeding;
14. 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.

Where this trial is running

Shanghai, Shanghai Municipality

• 180 Fenglin Road — Shanghai, Shanghai Municipality, China (Recruiting)

Study contacts

• Study coordinator: Wenzhi Pan, MD

Conditions Aortic Valve Stenosis; TAVR; Steerable Delivery System; Aortic Stenosis