麻豆传媒

Decisions made by the operator during surgical aortic valve replacement (SAVR) affected outcomes of aortic valve-in-valve (ViV) procedures years down the road, according to an analysis of the Valve-in-Valve International Data (VIVID) registry.

Size of the original failed bioprosthesis and the type of transcatheter valve implanted were linked to estimated survival at 8 years among the more than 1,000 ViV transcatheter aortic valve replacement (TAVR) patients studied:

• Small bioprosthesis (true internal diameter 20 mm or less), Edwards balloon-expandable valve: 26.6%
• Small bioprosthesis, Medtronic self-expanding valve: 37.6%
• Large bioprosthesis, Edwards balloon-expandable valve: 39.4%
• Large bioprosthesis, Medtronic self-expanding valve: 43.6%

Independent predictors of all-cause mortality were found to be , older age, reduced left ventricular ejection fraction, chronic kidney disease, non-transfemoral access, and diabetes, according to Danny Dvir, MD, of the University of Washington Medical Center in Seattle, who presented the study during the held virtually in lieu of the cancelled EuroPCR meeting.

Aortic valve reinterventions following the ViV procedure were more common with balloon-expandable TAVR valves (6% vs 2% for self-expanding ones, P=0.02) and with pre-existing severe patient-prosthesis mismatch (PPM; 12.5% vs 3% with no or moderate PPM, P=0.02).

Ultimately, reintervention was predicted by younger age, balloon-expandable valve, malposition, and pre-existing severe PPM.

"The size of the original failed valve may influence long-term mortality and the type of the transcatheter valve may influence the need for reintervention after aortic ViV," Dvir concluded. "Operator decisions during the original tissue valve implantation and/or during the ViV procedure may influence meaningful clinical outcomes."

The data highlighted the "importance of good preoperative planning" by surgeons using CT scans to select the best surgical valve for SAVR, agreed Vinayak Bapat, MBBS, of Abbott Northwestern Hospital in Minneapolis and the Minneapolis Heart Institute, who was not involved in the study.

Overall, the study results are "not surprising" and beg two questions, he said: Should bioprosthetic valves be used for SAVR (especially when true internal diameter is less than 20 mm and the patient is young and therefore likely to undergo ViV in the future)? And should ViV TAVR be when they may have better outcomes with redo surgery?

"The most important take-home message from this is that despite the excellent results that can be obtained for patients who require ViV TAVR for a failing surgical bioprosthesis, it isn't a perfect procedure, since we're often putting a TAVR valve inside a small surgical valve. The hemodynamics are not as good as they are in native annuli in patients who are receiving de novo TAVR procedures," commented Howard Herrmann, MD, of the Hospital of the University of Pennsylvania in Philadelphia.

Dvir's group accessed the VIVID registry to identify 1,006 patients with bioprosthetic valve failure who received ViV procedures before 2014. The cohort largely received Medtronic self-expanding valves or Edwards balloon-expandable valves.

Age at ViV TAVR was 77.7 on average, and 58.8% of patients were men. Pre-existing severe PPM was noted in 6.2% of the group.

True internal diameter of the failed valve was 19.9 mm on average. The median label size of the transcatheter valve was 23 mm.

Herrmann noted the difficulty of comparing valves in this study as the analysis was unadjusted, retrospective, and nonrandomized.

Nevertheless, he noted two things operators can do to optimize hemodynamics: place transcatheter valves as high as possible and fracture the surgical prosthesis to allow the TAVR valve to expand fully.

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