Aortic root distensibility and cross-sectional areas in stented and subcoronary stentless bioprostheses in pigs.
A flexible aortic root is essential for natural leaflet stress distribution. It is suggested that stentless bioprosthetic valves retain the flexibility of native valves. We investigated aortic root distensibility and cross-sectional area (CSA) in stentless (Solo, n=4; Toronto SPV, n=7), stented (Mitroflow, n=8) and in native valves (n=8) in pigs. Magnetic resonance imaging was performed to assess aortic root areas. At the annular level the Solo valve had a larger CSA (2.83+/-0.26 cm(2)) than both the Mitroflow (2.24+/-0.23 cm(2)) and Toronto SPV (1.87+/-0.59 cm(2)) (P=0.003; P=0.01). At the sino-tubular junction the Mitroflow valve had a significantly larger CSA (2.96+/-0.80 cm(2)) than the Toronto SPV (2.05+/-0.47 cm(2); P=0.02). At the annular level the percentage change in area between end-diastole and end-systole was lower for the Mitroflow than for all the other valves (P=0.006). No difference was found between native and stentless valves. In conclusion, the Solo valve had a larger CSA at the annulus than both the Mitroflow and the Toronto SPV. However, the stentless valves had a smaller CSA at the sino-tubular junction than the Mitroflow. We, furthermore, found that implantation of stentless heart valves preserves aortic root distensibility at the annular level in pigs.
Funder
Jonas Amstrup
JA
Department of Cardiothoracic and Vascular Surgery, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, DK-8200 Aarhus N, Denmark. funder@ki.au.dk
Ringgaard
Steffen
S
Frost
Markus Winther
MW
Wierup
Per
P
Klaaborg
Kaj-Erik
KE
Hjortdal
Vibeke
V
Nygaard
Hans
H
Hasenkam
John Michael
JM
D000818:Animals; D001021:Aortic Valve / Q000473:pathology / Q000503:physiopathology / Q000601:surgery*; D001696:Biomechanical Phenomena; D001705:Bioprosthesis; D004548:Elasticity; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000295:instrumentation*; D006439:Hemodynamics; D019028:Magnetic Resonance Imaging, Cine; D011474:Prosthesis Design; D015607:Stents; D013536:Suture Techniques; D013552:Swine