NEW YORK (Reuters Health) – The Edwards SAPIEN transcatheter valve tends to shift upward slightly during the final deployment stage, according to a report in the May JACC: Cardiovascular Interventions.
“Operators implanting Edwards SAPIEN devices need to be aware of the upper movement phenomenon,” researchers note. “In appropriate cases, operators should consider placing the center of the device 1 to 2 mm below the target line for implantation during the rapid-pacing phase.”
Dr. Ran Kornowski from the Rabin Medical Center in Petach Tikva, Israel, and colleagues at four major medical centers in France and Israel analyzed the Edwards SAPIEN device positions in different stages of implantation and quantified device movement during final deployment in a study of 68 patients with severe symptomatic native aortic valve stenosis.
“I would hope that our work would increase the awareness of the Edwards SAPIEN valve positioning and movement during the course of implantation, a finding that may affect the implantation technique,” Dr. Kornowski told Reuters Health by email.
On average, the valve moved 2 mm toward the aorta between the final rapid pacing period and device deployment, but ranged from moving downward 1.3 mm to moving upward 4.6 mm.
The upward movement of the device was asymmetrical, occurring mainly in the lower part of the device (mean, 3.2 mm) and less so in the upper part of the device (mean, 0.75 mm), which resulted in device shortening, according to the report.
The upward movement was independent of specific device model (Edwards SAPIEN vs Edwards SAPIEN XT), device size, and procedural access (transfemoral versus transapical).
Factors that influenced device movement during deployment included aortic valve calcification, aortic sinus volume, and aortic regurgitation severity, the research team says.
Final device position did not appear to correlate with clinical or hemodynamic results, but the researchers note that the study was not powered to evaluate these correlations.
“Valve malpositioning could be addressed using precise procedural planning, ensuring proper valve sizing well matched to the aortic annulus, and using careful procedural implantation techniques and corrective measures (e.g. a second valve implantation) in extreme cases when needed,” Dr. Kornowski concluded. “The use of ‘on line’ positioning tools is a great asset for this specific purpose.”
He cited the guidance technology from Paieon C-THV (Park Afek, Israel) as an example of a positioning tool; he serves on that company’s advisory board.
Dr. Kornowski added, “Our plan is to further explore the impact of valve positioning on procedural and clinical outcomes. In particular, we are interested in defining the impact of valve position on residual peri-valvular leaks immediately post TAVR procedures.”
J Am Coll Cardiol Intv 2012;5:563-570.