Does Undersizing of Transcatheter Aortic Valve Bioprostheses during Valve-in-Valve Implantation Avoid Coronary Obstruction? An In Vitro Study.
BackgroundThe transcatheter aortic valve-in-valve implantation (TAViVI) is an evolving treatment strategy for degenerated surgical aortic valve bioprostheses (SAVBs) in patients with high operative risk. Although hemodynamics is excellent, there is some concern regarding coronary obstruction, especially in SAVB with externally mounted leaflet tissue, such as the Trifecta (St. Jude Medical Inc., St. Paul, Minnesota, United States). We investigated coronary flow and hydrodynamics before and after TAViVI in a SAVB with externally mounted leaflet tissue (St. Jude Medical, Trifecta) with an undersized transcatheter aortic valve bioprosthesis (Edwards Sapien XT; Edwards Lifesciences LLC, Irvine, California, United States) in an in vitro study.Materials and MethodsAn aortic root model was constructed incorporating geometric dimensions known as risk factors for coronary obstruction. Investigating the validity of this model, we primarily performed recommended TAViVI with the Sapien XT (size 26 mm) in a Trifecta (size 25 mm) in a mock circulation. Thereafter, hydrodynamic performance and coronary flow (left/right coronary diastolic flow [lCF/rCF]) after TAViVI with an undersized Sapien XT (size 23 mm) in a Trifecta (size 25 mm) were investigated at two different coronary ostia heights (COHs, 8 and 10 mm).ResultsValidation of the model led to significant coronary obstruction (p< 0.001). Undersized TAViVI showed no significant reduction with respect to coronary flow (lCF: COH 8 mm, 0.90-0.87 mL/stroke; COH 10 mm, 0.89-0.82 mL/stroke and rCF: COH 8 mm, 0.64-0.60 mL/stroke; COH 10 mm, 0.62-0.58 mL/stroke). Mean transvalvular gradients (4-5 mm Hg,p< 0.001) increased significantly after TAViVI.ConclusionsIn our in vitro model, undersized TAViVI with the balloon-expandable Sapien XT into a modern generation SAVB (Trifecta) successfully avoided coronary flow obstruction.
Department of Cardiac and Thoracic Vascular Surgery, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Sina
S
Stock
Department of Cardiac and Thoracic Vascular Surgery, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Michael
M
Scharfschwerdt
Department of Cardiology, Angiology and Intensive Care Medicine, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Roza
R
Meyer-Saraei
Department of Cardiac and Thoracic Vascular Surgery, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Doreen
D
Richardt
Department of Cardiac and Thoracic Surgery, Universitätsklinikum Halle, Halle, Sachsen-Anhalt, Germany.
Efstratios I
EI
Charitos
Department of Cardiac and Thoracic Vascular Surgery, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Hans-Hinrich
HH
Sievers
Department of Cardiac and Thoracic Vascular Surgery, Universitätsklinikum Schleswig-Holstein, Lübeck, Schleswig-Holstein, Germany.
Thorsten
T
Hanke
D001021:Aortic Valve / Q000503:physiopathology / Q000601:surgery*; D063126:Balloon Valvuloplasty; D001705:Bioprosthesis; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D006439:Hemodynamics; D006801:Humans; D057446:Hydrodynamics; D008422:Materials Testing; D008953:Models, Anatomic; D008955:Models, Cardiovascular; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012307:Risk Factors; D065467:Transcatheter Aortic Valve Replacement / Q000009:adverse effects / Q000295:instrumentation*