Giovanni Stellin M.D.
Professor of Cardiac Surgery
Director of Pediatric and Congenital Cardiac Surgery Unit
University of Padua
ESISTE UN CONDOTTO MIGLIORE O UNA ALTERNATIVA MIGLIORE AL CONDOTTO
VALVOLATO VENTRICOLO DESTRO – ARTERIA POLMONARE?
Background
The RVOT reconstruction with the
establishment of an unobstructed and
competente pathway is a task that
nowadays congenital cardiac surgeons are
still seeking
• In the early 1980s, cryopreservation processes became widly available
• Cryopreserved valved homograft became the congenital heart surgeon’s conduit of choice for RVOT reconstruction
Cryopreserved Homograft
• Cryopreservation “know how” not always available all over the world
• Small conduits (< 14 mm) are in short suplly
• Long term accelerated fibrocalcification particularly severe in aortic homografts placed in the pulmunary position
• Blood group compatibility between donors vs recipent interfere with long term durability
Cryopreserved Homograft
Attributes of the “Ideal” RV-PA conduit
• Long term patency• Availability in a range of sizes• Excellent handling characteristics• Long term valve function• Growth potential• Low cost• Low infections potential• Non-thrombogenic
Alternatives to the homograft conduit
• Bovine internal jugular valved conduits
• Biological prosthesis
• Monocuspid patches
• Use of living autologous tissue in extra anatomic position
• Iliac artery homograft
Bovine internal jugular valved conduits
• Heterologous bovine jugular vein graft
• Containing a trileaflet venous valve and a natural sinus slightly larger than its lumen
• Conduit available in small sizes (12 mm to 22 mm)
• Clinical reports with early and mid term follow up have described excellent results
Blood group compatible homograft
Contegra
Cryopreserved homograft
Non-blood compatible homograft
Biological prosthesis
• Generally employed in treating long standing PR after TOF repair or after PV dilatation
• Available also in large sizes
• Advantages: best biological valve in the long-term
Stentless porcine aortic root
Biological bioprosthesis
Monocuspid Patches• Pulmunary valve
Homograft monocusp
• Home made PTFE 0,1 membrane monocusp
• CorMatrix monocuspid
It is a bioscaffold. When implanted, the tissue acts as a scaffold into which the patient’s cells migrate and integrate, stimulating the patient’s natural wound-healing mechanisms.
Monocuspid Patches
Use of living autologous tissue in extra anatomic position (LAA)
The LAA is pulled anteriorly and interposed between the PAs and the edge of the right ventriculotomy. The ceiling of the conduit is filled with a monocusp patch
Advantages: growth potential
• New option for a restrictive to RV –PA conduit or MBTS
• Less pulmonary artery distorsion due to better pliability
• No need of anticoagulation therapy
• Less bleeding from the suture lines
• No thrombosis linked to prosthetic material
Iliac artery homograft
Ideal Prosthesis in the next future?
Heart Valve Tissue engineering
Heart Valve Tissue engineering
Conclusions
• Still no ideal conduit for RVOT reconstruction
• Tailoring the conduit to the patient’s needs
• Favour the use of autologous tissue possibily in combination with cellularized bioscaffold tissue
Future Prospective
• Think about future: percutaneous valve implantation
• Improve the Heart valve Tissue Engineering programme
Palazzo del Bo’
University of Padua Medical School
