Application of TAVI at Experienced Interventional Cardiac Centers Without On-site Cardiac Surgery (ATLAS Study)

The purpose of this study is to see if having the Transcatheter Aortic Valve Replacement (TAVR) procedure done in a hospital with onsite cardiac surgery available or not, makes a difference on participant outcomes. Current standard of care is to have this procedure done in a hospital with onsite cardiac surgery available.

Hypothesis

The investigators hypothesize that the TAVR in experienced interventional cardiac centers without on-site cardiac surgery will be safe and effective. Although this is happening clinically in select regions internationally, this change in the clinical application of TAVI requires a rigorous assessment of safety with a robust randomized trial and multicenter international collaboration.

Primary Objectives:

The primary efficacy objective is to determine whether a Transcatheter Aortic Valve Implantation (TAVI) procedure performed by experienced operators in centers without on-site cardiac surgery is non-inferior to a TAVI procedure performed by experienced operators in centers with on-site cardiac surgery in terms of all-cause death, myocardial infarction, stroke and hospitalization for heart failure. The primary safety objective is to demonstrate that mortality associated with periprocedural complications actionable by emergent cardiac surgery (ECS) did not differ between study arms.

Research method/Procedures

ATLAS is an all-comer, prospective, randomized, multicenter, open label trial with blinded adjudicated evaluation of outcomes. The ATLAS study will involve centers without on-site cardiac surgery, but with experienced operators already performing TAVI. Participants will be recruited after Heart Team discussion and approval for TAVI. The eligibility of each participant will be confirmed by an established multidisciplinary Heart Team. Once approved for TAVI, dedicated review of the ATLAS study inclusion and exclusion criteria will occur. Study patients meeting inclusion and having no exclusion criteria will be randomized in a 2:1 fashion to TAVI performed in the experimental or standard of care arm stratified by two groups: 1) inoperable/high risk and 2) intermediate/low risk.

Randomization:

EXPERIMENTAL ARM: TAVI WITHOUT ON-SITE SURGERY After randomization, the participant will be scheduled to undergo TAVI by experienced operators with appropriately trained cardiac catheterization staff. CONTROL ARM: TAVI WITH ON-SITE SURGERY After randomization, the patient will be scheduled to undergo TAVI by experienced operators with appropriately trained cardiac catheterization staff at an established TAVI center with on-site cardiac surgery

Schedule of events:

1. Pre-eligibility screening 2. Inclusion/Exclusion criteria review 3. Randomization 4. 1-month post randomization 5. 3-months post randomization 6. TAVI procedure hospitalization 7. 1-month visit after TAVI 8. 12-month visit after TAVI 9. Final follow-up visit - 12-month post TAVI in control arm and equivalent median time post randomization in the intervention arm

Eligibility Criteria:
Inclusion Criteria:

* Severe symptomatic AS reviewed and accepted for Transfemoral (TF) TAVI by an established Heart Team
* Obtained informed consent

Exclusion Criteria:

* Ambiguous aortic annular sizing on CT measurement deemed to increase the risk of valve embolization
* Hostile aortic root on CT for TAVI implantation defined by, but not limited to:
* High risk LVOT with a dimension significantly smaller than the annulus and/or extensive calcification
* Features that increase the risk of coronary artery occlusion including inadequate coronary artery height and/or shallow coronary sinuses in the setting of a significant coronary artery territory at risk (accounting for prior CABG)
* High risk STJ anatomy defined by inadequate height and/or diameter and/or excessive calcification
* Vascular anatomy with increased risk of ascending aorta trauma (i.e. combinations of existing ascending aortic aneurysm, and/or unfolded aorta and/or extensive tortuosity and/or excessive iliofemoral calcification)
* GFR \<15, excluding patients on dialysis
* Life expectancy less than 3 years
* Any factor precluding 1-year follow-up