| Registry | NCT07872020, acronym SYMMETRY |
|---|---|
| Status | Not yet recruiting |
| Phase | Not applicable |
| Study type | Interventional; randomized, parallel, masking: none, treatment |
| Enrollment | 422 (Estimated) |
| Sponsor | Erasmus Medical Center (Other); collaborators: Edwards Lifesciences |
| Conditions | Aortic Valve Stenosis and/or Insufficiency, Hypoattenuated Leaflet Thickening, Valve Expansion, Transcatheter Aortic Valve Replacement |
| Interventions | Double-TAP post-dilatation (Procedure) |
| Dates | start 2026-11-01 (estimated), primary completion 2028-11-01 (estimated), completion 2033-11-01 (estimated), first posted 2026-10-13, last updated 2026-10-16 |
| Locations | 5 sites in Germany, Netherlands |
Related Papers Related Patents Related Grants Related Experts
All trials for Aortic Valve Stenosis and/or Insufficiency All trials for Hypoattenuated Leaflet Thickening All trials of Double-TAP post-dilatation
Rationale: Transcatheter aortic valve implantation (TAVI) has become the standard of care for aortic stenosis across all surgical risk categories, including low-risk, younger patients (≥70 years). As many of these patients are expected to outlive their prosthetic valves, the durability of the valve becomes an increasingly critical factor. Hypoattenuated leaflet thickening (HALT), a finding on post-TAVI computed tomography (CT), occurs in approximately 20% of patients and is associated with bioprosthetic valve dysfunction. Balloon-expandable valves seem more susceptible to HALT with an occurrence rate of 21%, compared to 16% for self-expanding valves.
A recent study identified underexpansion of the transcatheter heart valve prosthesis as a key predictor of HALT at 30 days, which in turn was associated with a sixfold increase in cardiovascular mortality and a threefold increase in all-cause mortality at 1 year. Moreover, data suggest that, in the absence of post-dilatation, more than 95% of balloon-expandable valve implants exhibit some degree of underexpansion. In contrast, routine post-dilatation enhances valve expansion and hemodynamic performance without significantly increasing adverse events. The double-TAP technique-re-inflation of the TAVI delivery balloon after initial valve deployment-achieves a 9-10% increase in valve frame expansion, potentially reducing HALT risk and improving long-term outcomes.
Objective: To determine whether routine double-TAP post-dilatation after balloon-expandable TAVI is safe and can reduce the incidence of HALT.
Study design: Investigator-initiated, multicenter, open-label, randomized trial with 1:1 allocation to routine post-dilatation using double-TAP versus no post-dilatation immediately after balloon expandable valve deployment.
Study population: 422 Patients undergoing balloon-expandable TAVI for native aortic valve stenosis Investigational intervention: TAVI with a balloon-expandable valve followed by double-TAP post-dilatation.
Study design: Investigator-initiated, multicenter, open-label, randomized trial with 1:1 allocation to routine post-dilatation using double-TAP versus no post-dilatation immediately after balloon expandable valve deployment.
Study population: 422 Patients undergoing balloon-expandable TAVI for native aortic valve stenosis
Investigational intervention: TAVI with a balloon-expandable valve followed by double-TAP post-dilatation.
| Arm | Type | Interventions | Description |
|---|---|---|---|
| Double-TAP post-dilatation | Active comparator | Procedure: Double-TAP post-dilatation | |
| No post-dilatation | No intervention |
Sex: All, ages: 70 Years to any
Inclusion Criteria: * Age ≥ 70 years * Patients with severe aortic stenosis undergoing TAVI with a balloon-expandable valve * Written informed consent Exclusion Criteria: * Significant valve frame under-expansion and/or ≥ moderate paravalvular leakage warranting post-dilatation at the discretion of the treating physician * Shallow implantation depth with increased risk of valve embolization upon post-dilatation * Sievers type 1 bicuspid aortic valve with calcified raphe * Indication for oral anticoagulant therapy * Estimated glomerular filtration rate <30 ml/min * Iodine contrast allergy
| Facility | City | Country | Status |
|---|---|---|---|
| Uniklinik Düsseldorf | Düsseldorf | Germany | |
| Amsterdam University Medical Center | Amsterdam | Netherlands | |
| Amphia Hospital | Breda | Netherlands | |
| Maastricht University Medical Center | Maastricht | Netherlands | |
| Erasmus Medical Center Rotterdam | Rotterdam | Netherlands |