Disparity Seen Between Aortic Valve-in-Valve Implantation for Stented, Stentless Devices

Aortic valve-in-valve implantation in failed stentless bioprostheses results in more device malposition and coronary occlusion than in stented bioprostheses, though treatment of the former yielded better hemodynamics, according to an analysis from the Global Valve-in-Valve Registry presented at TCT 2014. Mortality rates with the two groups were similar in spite of those differences.

Danny Dvir, MD,of St. Paul’s Hospital in Vancouver, Canada, and colleagues assessed 553 procedures—441 in stented bioprostheses and 112 in stentless bioprostheses.

Device malposition occurred more often in stentless valves (16.1%) and Mosaic stented valves (Medtronic; 14.0%) than in non-Mosaic stented valves (9.0%; P=.03). Coronary occlusion was more common and post-procedural aortic valve gradient was lower with stentless devices. Additionally, valves without stents were more often treated with CoreValve (Medtronic) vs. Sapien (Edwards Lifesciences) and with rather than without transesophageal echocardiography (TEE; see Table).

Dvir.Sat

Mortality rates were similar between the stentless and stented cohorts at both 30 days (6.6% vs. 8.9%; P=.39)and 1 year (16.6% vs. 17.9%; P=.68).

“Stentless surgical valves are very different from conventional stented surgical valves,” Dvir told TCT Daily. “Some of these stentless devices fail with severe root calcification, which makes redo surgery very risky. This is why we must understand the specific issues with the less-invasive valve-in-valve approach in stentless devices.”

Patients with failed stentless devices in this study were younger than those with stented bioprostheses (73.4 vs. 78.6 years; P<.001). The groups had similar STS scores, but stentless bioprostheses had a longer median implantation-to-failure time (11 vs. 9 years; P=.02) and failed more commonly with predominant regurgitation (58.9% vs. 21.8%; P<.001).
Lastly, treatment of stentless devices resulted in a lower degree of stenosis than those with stents (valve area 1.28 cm2 vs. 0.88 cm2; P<.001).

Dvir said that the increased rate of malposition was expected because stentless bioprostheses lack fluoroscopic markers, but he found the other differences surprising. In particular, the discrepancy in mean aortic valve gradient was dramatic, he said, pointing out that the stentless devices were more commonly treated with self-expanding valves and failed more commonly due to regurgitation—both predictors of better post-procedural hemodynamics.

“Interventionists aiming to perform a stentless valve-in-valve procedure should focus on reducing and preventing the risks of malposition and coronary obstruction, which seem to be higher,” Dvir said. “Cardiac surgeons considering the type of surgical device to implant should be aware that a stentless device may enable better hemodynamics and hypothetically better durability post–valve-in-valve, when that device fails years later.”


Disclosures:

  • Dvir reports no relevant conflicts of interest.

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