Alternative Access Approaches for Transcatheter Aortic Valve Replace (TAVR) in Inoperable Patients With Aortic Stenosis

Overview

Investigational study of Edwards Lifesciences, LLC's "Edwards SAPIEN Transcatheter Heart Valve" for non-femoral delivery, (or alternative access deliver) in patients with severe symptomatic native aortic valve stenosis who have been determined by a cardiac surgeon to be inoperable for open aortic valve replacement and in whom existing co-morbidities would not preclude the expected benefit from correction of the aortic stenosis. Will outcomes observed in a high-risk operable transapical native valve TAVR cohort receiving an Edwards SAPIEN device compare to inoperable patients undergoing alternative access TAVR with the Edwards SAPIEN device experience a reasonably similar incidence of 30 day adverse events?

Transcatheter aortic valve replacement (TAVR) using the Edwards SAPIEN valve and Retroflex 3 delivery system provides both a mortality and quality of life benefit for inoperable patients. Only the transfemoral (TF) access has been approved in the US. A substantial number of patients cannot have a TF approach due to inadequate vessel size, vessel disease, or other anatomical considerations. The pivotal study did not include an assessment of safety and effectiveness of alternative access approaches in this inoperable patient group. Early approaches to TAVR included a femoral transvenous approach with transseptal access to the left side for delivery of the valve. This approach avoided large bore arterial catheterization, but it had unacceptable rates of complications and lacked reproducibility. Alternative access approaches have been developed because of the risks associated with inserting large caliber catheters into small, diseased femoral arteries often associated with diffuse vasculopathy. To avoid the vascular complications from femoral access, other transcatheter approaches have been developed to include open surgical access to the left ventricular apex (TA), ascending aorta, (TAO), subclavian and axillary arteries (TS), and retroperitoneal access to the iliac artery (TI) as well as distal aorta. In addition to providing TAVR to patients who cannot have TF access, additional advantages include better catheter control and safer closure of the access site. Commonly cited disadvantages include the need for surgical expertise and additional equipment, along with the potential for longer recovery, more incisional pain, greater radiation exposure for operators, unsuitable delivery catheters for alternative access sites, and a host of unique alternative access site complications. We propose to collectively analyze 30-day safety endpoints as a lumped data group for these alternative access approaches. These data are gathered from clinical practice in real-world settings and submitted to the TVT Registry. It is expected that centers will choose among the various choices for alternative access based the causative factors underlying the need for alternative access, as well as local skill sets and experience. For this lumped data group of alternative access approaches we will compare 30-day safety results to the TA outcomes reported from Cohort A of the PARTNERS 1 trial. We recognize that these TA patients were high risk operable patients rather than inoperable patients, but no other direct comparator group is available. We reason that the TA data from this published clinical trial are high quality, represent an alternative access approach rather than TF, and will provide a frequency of safety endpoints that have been found to be acceptable both clinically and from a regulatory perspective.