Transcatheter Aortic Valve Implantation for Failing Surgical Aortic Bioprosthetic Valve

Abstract

With an aging population, improvement in life expectancy, and significant increase in the use of bioprosthetic valves, structural valve deterioration will become more and more prevalent. The operative mortality for an elective redo aortic valve surgery is reported to range from 2% to 7%, but this percentage can increase to more than 30% in high-risk and nonelective patients. Because transcatheter aortic valve (TAV)-in-surgical aortic valve (SAV) implantation represents a minimally invasive alternative to conventional redo surgery, it may prove to be safer and just as effective as redo surgery. Of course, prospective comparisons with a large number of patients and long-term follow-up are required to confirm these potential advantages. It is axiomatic that knowledge of the basic construction and dimensions, radiographic identification, and potential failure modes of SAV bioprostheses is fundamental in understanding key principles involved in TAV-in-SAV implantation. The goals of this paper are: 1) to review the classification, physical characteristics, and potential failure modes of surgical bioprosthetic aortic valves; and 2) to discuss patient selection and procedural techniques relevant to TAV-in-SAV implantation.

Transcatheter Aortic and Mitral Valve‐in‐Valve Implantation Using the Edwards Sapien 3 Heart Valve

“…An inadequately expanded THV may be at risk of elevated transvalvular gradient because of inadequate leaflet expansion and mobility, also potentially increasing the risk of accelerated leaflet degeneration 1, 2, 4, 11…”

“…An important component of performing the VIV procedure starts with an in‐depth understanding of the failed bioprosthetic valve, which includes the following: the type of valve used (stented, stentless, sutureless, transcatheter valve), its structural elements, the technical details of the primary valve surgery (intra‐annular versus supra‐annular), and the cause of bioprosthetic valve failure (wear and tear, calcification, endocarditis, thrombosis, leaflet dysfunction, and pannus formation) 1, 2, 4, 5, 12. Selection of the THV size for the aortic and mitral VIV implantation depends on many factors listed above.…”

“…The sizing and labeling of the surgical bioprosthetic valves are not standardized and vary widely based on the different manufacturers. The minimum internal diameter of the surgical bioprosthetic valve may vary markedly from the given labeled valve size1, 2, 4, 5 (Figure 1); label size alone is therefore not suitable as a guide to THV size selection.…”

“…Balloon sizing is not routinely recommended in VIV procedures, as there is an increased risk of embolization or creating aortic insufficiency,1, 2, 4, 6 which can result in acute hemodynamic instability. However, in addition to selecting the size of the THV based on the T‐ID of the initially implanted bioprosthetic valve, balloon sizing can provide additional information and better understanding in selected cases such as when the CT‐ID suggests a smaller size S3 may be suitable, borderline valve sizes, stentless bioprostheses, or valves with a high risk of coronary artery obstruction.…”

“…Surgical valve replacement using mechanical or tissue prosthesis has remained the preferred therapy for several decades. In contrast to mechanical valves, the use of bioprosthetic valves to treat significant aortic valve stenosis (AS) or aortic valve regurgitation (AR) in the native aortic valve has continued to increase over time 1, 2. Bioprosthetic valves are advantageous to patients as they negate the need for long‐term anticoagulation therapy; however, they have limited durability and are expected to degenerate within 5 to 20 years 2, 3, 4.…”