Advertisement

Options for Prosthetic Pulmonary Valve Replacement

      This article reviews current data on various prostheses utilized for pulmonary valve replacement. Durability data is reviewed and risk factors for deterioration are examined. Finally, the choice of prosthesis should be tailored to the specific clinical scenario based on existing data regarding durability and risk factors.

      Introduction

      Prosthetic valves and conduits are utilized as a part of complete repair for numerous congenital cardiac defects. The most common diagnoses necessitating primary valved conduit placement in infancy include tetralogy of Fallot, pulmonary atresia – with intact ventricular septum or ventricular septal defect, truncus arteriosus, transposition of the great vessels with ventricular septal defect (as part of Rastelli procedure), interrupted aortic arch with diminutive ascending aorta (as part of Yasui-type repair), and severe congenital aortic stenosis (as part of Ross procedure). Implantation of stented bioprosthetic valve without conduit is indicated for patients with pulmonary regurgitation who have undergone previous right ventricular outflow tract reconstruction (RVOT) as a component of management of congenital heart defects. The indications for valve replacement in these patients have evolved over the past decade, with a trend toward earlier replacement to prevent the deleterious effects of long-standing pulmonary regurgitation on right ventricular function, dilation, and tricuspid regurgitation. The options for conduit and valve replacement include synthetic-, homograft-, and xenograft-based prostheses. Unfortunately, none of the currently available conduits are ideal, and each is associated with specific advantages and disadvantages.

      Homografts

      Cryopreserved aortic and pulmonary homografts may be used for RVOT reconstruction. The advantages of homografts include availability in a wide range of sizes and favorable handling characteristics during implantation. Bifurcating pulmonary grafts or aortic branch vessels can be directly anastomosed to branch pulmonary arteries in the absence of adequate central pulmonary arteries. Major disadvantages include limited supply of the smaller sizes necessary for neonatal repair, the limited shelf life of each homograft (approximately 2 years), and high cost. Modification of an homograft by excision of one leaflet and creation of a smaller “bicuspid” homograft allows the use of larger-sized homografts in smaller patients when appropriate-sized smaller homografts are unavailable.
      • McMullan D.M.
      • Oppido G.
      • Alphonso N.
      • et al.
      Evaluation of downsized homograft conduits for right ventricle-to-pulmonary artery reconstruction.
      Freedom from reintervention rates reported in the literature range widely, from 30% to over 80% at 10 years.
      • Boethig D.
      • Goerler H.
      • Westhoff-Bleck M.
      • et al.
      Evaluation of 188 consecutive homografts implanted in pulmonary position after 20 years.
      • Meyns B.
      • Jashari R.
      • Gewillig M.
      • et al.
      Factors influencing the survival of cryopreserved homografts The second homograft performs as well as the first.
      • Niwaya K.
      • Knott-Craig C.J.
      • Lane M.M.
      • et al.
      Cryopreserved homograft valves in the pulmonary position: risk analysis for intermediate-term failure.
      • Tweddell J.S.
      • Pelech A.N.
      • Frommelt P.C.
      • et al.
      Factors affecting longevity of homograft valves used in right ventricular outflow tract reconstruction for congenital heart disease.
      Smaller conduit size (or younger age at operation) has been consistently shown in multiple series to be a risk factor for homograft conduit failure. Freedom from reoperation at 10 years is <50% for homografts of <19 mm diameter.
      • Boethig D.
      • Goerler H.
      • Westhoff-Bleck M.
      • et al.
      Evaluation of 188 consecutive homografts implanted in pulmonary position after 20 years.
      Other factors that have less consistently been shown to increase the risk of failure include use of aortic homografts, residual branch pulmonary artery stenosis, ABO mismatch, and non-Ross operation (particularly operation for truncus arteriosus).
      • Tweddell J.S.
      • Pelech A.N.
      • Frommelt P.C.
      • et al.
      Factors affecting longevity of homograft valves used in right ventricular outflow tract reconstruction for congenital heart disease.
      • Askovich B.
      • Hawkins J.A.
      • Sower C.T.
      • et al.
      Right ventricle-to-pulmonary artery conduit longevity: is it related to allograft size?.
      • Sierra J.
      • Christenson J.T.
      • Lahlaidi N.H.
      • et al.
      Right ventricular outflow tract reconstruction: what conduit to use? Homograft or Contegra?.
      • Rodefeld M.D.
      • Ruzmetov M.
      • Turrentine M.W.
      • et al.
      Reoperative right ventricular outflow tract conduit reconstruction: risk analyses at follow up.
      • Brown J.W.
      • Ruzmetov M.
      • Rodefeld M.D.
      • et al.
      Right ventricular outflow tract reconstruction with an allograft conduit in non-ross patients: risk factors for allograft dysfunction and failure.
      • Brown J.W.
      • Ruzmetov M.
      • Fukui T.
      • et al.
      Fate of the autograft and homograft following Ross aortic valve replacement: reoperative frequency, outcome, and management.
      The reason for the discrepancy in durability between Ross and non-Ross patients is unclear, but may be related to orthotopic position of the conduit in the former; it is placed more anteriorly in Rastelli, Yasui, and truncus repairs, which may predispose to compression from the sternum. Several studies have shown superiority of pulmonary homografts over aortic homografts in patients with normal pulmonary artery pressures. However, pseudoaneurysm and fusiform conduit dilation are more common with pulmonary homografts when implanted into patients with elevated pulmonary artery pressures.
      • Niemantsverdriet M.B.
      • Ottenkamp J.
      • Gauvreau K.
      • et al.
      Determinants of right ventricular outflow tract conduit longevity: a multinational analysis.
      • Bando K.
      • Danielson G.K.
      • Schaff H.V.
      • et al.
      Outcome of pulmonary and aortic homografts for right ventricular outflow tract reconstruction.
      • DeLeon S.Y.
      • Tuchek J.M.
      • Bell T.J.
      • et al.
      Early pulmonary homograft failure from dilatation due to distal pulmonary artery stenosis.
      • Levine J.C.
      • Mayer Jr, J.E.
      • Keane J.F.
      • et al.
      Anastomotic pseudoaneurysm of the ventricle after homograft placement in children.
      Decellularized grafts may demonstrate mild improvement in durability compared with standard grafts.
      • Konuma T.
      • Devaney E.J.
      • Bove E.L.
      • et al.
      Performance of CryoValve SG decellularized pulmonary allografts compared with standard cryopreserved allografts.
      • Burch P.T.
      • Kaza A.K.
      • Lambert L.M.
      • et al.
      Clinical performance of decellularized cryopreserved valved allografts compared with standard allografts in the right ventricular outflow tract.
      Although some studies have shown that ABO-compatible and HLA-matched homografts are more durable than unmatched homografts, this observation has not been consistently demonstrated.
      • Sierra J.
      • Christenson J.T.
      • Lahlaidi N.H.
      • et al.
      Right ventricular outflow tract reconstruction: what conduit to use? Homograft or Contegra?.
      • Baskett R.J.
      • Nanton M.A.
      • Warren A.E.
      • et al.
      Human leukocyte antigen-DR and ABO mismatch are associated with accelerated homograft valve failure in children: implications for therapeutic interventions.

      Xenograft Conduits

      The most commonly used conduits include bovine jugular vein grafts, porcine pulmonary valved conduit (Shelhigh Inc., Milburn, NJ, USA), and porcine aortic root (Medtronic, Inc., Minneapolis, MN, USA). Advantages of xenograft conduits include abundant supply, availability of small conduits for neonatal applications, excellent handling characteristics, and low cost. The Medtronic Freestyle porcine aortic root has been used for RVOT reconstruction, and is available in sizes ranging from 19 mm to 29 mm.
      • Hartz R.S.
      • Deleon S.Y.
      • Lane J.
      • et al.
      Medtronic freestyle valves in right ventricular outflow tract reconstruction.
      The Shelhigh No-React treated pulmonary artery conduit is available in sizes 10 to 24 mm, and thus may be used during neonatal reconstruction. The Medtronic Contegra graft, obtained from bovine jugular vein, consists of a venous valve within a jugular vein conduit. It is available in multiple sizes ranging from 12 mm to 22 mm. The smaller sizes are well-suited for neonatal RVOT reconstruction, and are an alternative to homograft conduits.
      Extensive durability data on the Shelhigh pulmonary artery conduit are lacking, and several studies have documented early graft failure with the smaller sized conduits (<16 mm) because of intimal peel formation in the distal conduit.
      • Schreiber C.
      • Sassen S.
      • Kostolny M.
      • et al.
      Early graft failure of small-sized porcine valved conduits in reconstruction of the right ventricular outflow tract.
      • Kim W.H.
      • Min S.K.
      • Choi C.H.
      • et al.
      Follow-up of Shelhigh porcine pulmonic valve conduits.
      The Medtronic Freestyle porcine aortic root (>19 mm) appears to have excellent durability at short-term follow-up, but long-term data are pending.
      • Erez E.
      • Tam V.K.
      • Doublin N.A.
      • et al.
      Repeat right ventricular outflow tract reconstruction using the Medtronic Freestyle porcine aortic root.
      • Kanter K.R.
      • Fyfe D.A.
      • Mahle W.T.
      • et al.
      Results with the freestyle porcine aortic root for right ventricular outflow tract reconstruction in children.
      Data reported in the literature regarding durability of the bovine jugular vein graft varies significantly, with freedom from reintervention ranging between 66% at 3 years to 90% at 7 years.
      • Sierra J.
      • Christenson J.T.
      • Lahlaidi N.H.
      • et al.
      Right ventricular outflow tract reconstruction: what conduit to use? Homograft or Contegra?.
      • Shebani S.O.
      • McGuirk S.
      • Baghai M.
      • et al.
      Right ventricular outflow tract reconstruction using Contegra valved conduit: natural history and conduit performance under pressure.
      • Brown J.W.
      • Ruzmetov M.
      • Rodefeld M.D.
      • et al.
      Valved bovine jugular vein conduits for right ventricular outflow tract reconstruction in children: an attractive alternative to pulmonary homograft.
      Young age at implantation is risk factor for reintervention and distal conduit stenosis.
      • Sekarski N.
      • van Meir H.
      • Rijlaarsdam M.E.
      • et al.
      Right ventricular outflow tract reconstruction with the bovine jugular vein graft: 5 years' experience with 133 patients.
      In patients with elevated right-ventricular pressures or pulmonary hypertension, the Contegra has been associated with graft dilation and decreased durability, raising concerns for its use in these patients.
      • Shebani S.O.
      • McGuirk S.
      • Baghai M.
      • et al.
      Right ventricular outflow tract reconstruction using Contegra valved conduit: natural history and conduit performance under pressure.
      • Sekarski N.
      • van Meir H.
      • Rijlaarsdam M.E.
      • et al.
      Right ventricular outflow tract reconstruction with the bovine jugular vein graft: 5 years' experience with 133 patients.
      • Bautista-Hernandez V.
      • Kaza A.K.
      • Benavidez O.J.
      • et al.
      True aneurysmal dilatation of a Contegra conduit after right ventricular outflow tract reconstruction: a novel mechanism of conduit failure.

      Transcatheter Valves

      Several manufacturers have developed transcatheter valves for application in the pulmonary position. The Melody valve (Medtronic, Inc.) consists of a bovine jugular vein segment mounted within a platinum-iridium stent. The device is currently approved for percutaneous implantation within previously placed conduits. Recent experience with percutaneous implantation of the Melody valve in the RVOT has shown encouraging intermediate-term durability in adolescent patients.
      • Lurz P.
      • Gaudin R.
      • Taylor A.M.
      • et al.
      Percutaneous pulmonary valve implantation.
      Data from a recent multicenter trial has shown freedom from valvular dysfunction of 93% at 1 year, suggesting excellent short-term outcomes in this cohort of patients.
      • McElhinney D.B.
      • Hellenbrand W.E.
      • Zahn E.M.
      • et al.
      Short- and medium-term outcomes after transcatheter pulmonary valve placement in the expanded multicenter US melody valve trial.

      Synthetic Valved Conduits

      Composite conduits made of Dacron or Polytetrafluoroethylene (PTFE) tube grafts with bioprosthetic or mechanical valves are available commercially, or can be constructed manually at the time of the operation. Commercially available valve conduits include the Carpentier-Edwards and Hancock conduits, which utilize a porcine valve within a Dacron tube. Manually constructed composite conduits use a bioprosthetic valve within either a Dacron or PTFE tube graft. Advantages of the synthetic valved conduits include excellent longevity and virtually unlimited shelf life, which makes them readily available. The pericardial valves have a rigid annulus that is resistant to distortion or compression by external structures (sternum). The major disadvantage of these conduits includes the size limitation, which excludes its applicability in neonates and small children. These conduits are applicable in older children and young adults. Unlike tissue conduits, these conduits are not amenable to catheter-based dilation or stenting if the child were to outgrow the conduit. Thus, an “adult” size is often implanted even in older children. Previous studies suggested inferior durability of these conduits compared with homografts, but recent studies have challenged this result.
      • Homann M.
      • Haehnel J.C.
      • Mendler N.
      • et al.
      Reconstruction of the RVOT with valved biological conduits: 25 years experience with allografts and xenografts.
      Earlier histologic studies showed development of thick fibrous peels within the lumen of Dacron conduits, but introduction of recent modifications to Dacron processing have reduced the incidence of this complication.
      • Kobayashi J.
      • Backer C.L.
      • Zales V.R.
      • et al.
      Failure of the Hemashield extension in right ventricle-to-pulmonary artery conduits.
      • Agarwal K.C.
      • Edwards W.D.
      • Feldt R.H.
      • et al.
      Pathogenesis of nonobstructive fibrous peels in right-sided porcine-valved extracardiac conduits.

      Options for Pulmonary Valve Replacement

      Several options exist for pulmonary valve replacement in patients beyond infancy. Implantation within native RVOT with or without pulmonary artery augmentation is the most common technique of implantation following transannular repair of tetralogy of Fallot. Placement within synthetic conduit (described above) may be necessary for replacement of calcified or foreshortened conduits.

      Mechanical Valves

      Despite the theoretical advantages of long-term durability of mechanical valves, concerns regarding risks of long-term anticoagulation and valve thrombosis, despite adequate anticoagulation, have limited extensive use of these prostheses. Risk of thrombosis may be higher in patients with right-ventricular dysfunction.
      • Dos L.
      • Munoz-Guijosa C.
      • Mendez A.B.
      • et al.
      Long term outcome of mechanical valve prosthesis in the pulmonary position.
      Several small series have reported acceptable durability of the mechanical prosthesis in the pulmonary position, with mode of failure being growth of fibrosis rather than mechanical failure or thrombosis events.
      • Waterbolk T.W.
      • Hoendermis E.S.
      • den Hamer I.J.
      • et al.
      Pulmonary valve replacement with a mechanical prosthesis Promising results of 28 procedures in patients with congenital heart disease.
      • Haas F.
      • Schreiber C.
      • Horer J.
      • et al.
      Is there a role for mechanical valved conduits in the pulmonary position?.
      Use of mechanical valves may be justified in patients requiring anticoagulation for other reasons, in patients likely to be compliant with long-term anticoagulation, and those in whom risk of reoperation is deemed to be unusually high.

      Bioprosthetic Valves

      Stented bioprosthetic valves have been designed and FDA-approved for use in the aortic position, but have been implanted extensively in the pulmonary position. The most commonly utilized xenograft valves are the porcine and bovine pericardial valves. Data from performance in the aortic position suggests that bovine pericardial valves are more durable than porcine valves, but this difference has not been demonstrated in the pulmonary position.
      • Rahimtoola S.H.
      Choice of prosthetic heart valve in adults an update.
      • Zubairi R.
      • Malik S.
      • Jaquiss R.D.
      • et al.
      Risk factors for prosthesis failure in pulmonary valve replacement.
      Calcification is the mode of failure of bioprosthetic valves in the aortic position, and several manufacturers have developed anticalcification treatment processes to limit this complication. In a retrospective review of 229 pulmonary valve implantations at Children's Hospital Boston, no differences in freedom from structural valve deterioration could be found between several bioprosthetic valve types at short-term follow-up, with freedom from reintervention of approximately 94% at 5 years.

      Considerations for Choice of Prosthesis

      For the neonate or infant undergoing valved conduit placement, homografts and bovine jugular vein grafts are the only options. Factors to consider include anticipated pulmonary artery pressures and nature of concomitant operation. In neonates and infants with normal pulmonary artery pressures, several studies have shown superior durability of pulmonary homografts compared with aortic homografts and bovine jugular vein grafts.
      • Tweddell J.S.
      • Pelech A.N.
      • Frommelt P.C.
      • et al.
      Factors affecting longevity of homograft valves used in right ventricular outflow tract reconstruction for congenital heart disease.
      • Niemantsverdriet M.B.
      • Ottenkamp J.
      • Gauvreau K.
      • et al.
      Determinants of right ventricular outflow tract conduit longevity: a multinational analysis.
      • Bando K.
      • Danielson G.K.
      • Schaff H.V.
      • et al.
      Outcome of pulmonary and aortic homografts for right ventricular outflow tract reconstruction.
      • Albert J.D.
      • Bishop D.A.
      • Fullerton D.A.
      • et al.
      Conduit reconstruction of the right ventricular outflow tract Lessons learned in a twelve-year experience.
      Yet other studies have demonstrated similar freedom from reintervention between bovine jugular vein graft and homografts. However, these studies group pulmonary and aortic homografts together for this analysis, which prevents comparison of bovine jugular vein graft to pulmonary homograft.
      • Sierra J.
      • Christenson J.T.
      • Lahlaidi N.H.
      • et al.
      Right ventricular outflow tract reconstruction: what conduit to use? Homograft or Contegra?.
      • Hickey E.J.
      • McCrindle B.W.
      • Blackstone E.H.
      • et al.
      Jugular venous valved conduit (Contegra) matches allograft performance in infant truncus arteriosus repair.
      If reoperation is planned within a short time interval as a part of staged repair strategy, implantation of a low-cost but less durable conduit may be acceptable. In the presence of elevated pulmonary pressures, pulmonary homografts and bovine jugular vein grafts are at an increased risk of pseudoaneurysm formation, and thus aortic homografts are preferred. When the central pulmonary arteries are absent or hypoplastic, use of a bifurcating pulmonary or aortic homograft instead of bovine jugular vein graft simplifies reconstruction. The practice of implanting an oversized homograft into neonates and small children to increase the time to replacement has been challenged by several studies that have found that homograft oversizing does not improve conduit longevity, and may even result in decreased longevity in children.
      • Askovich B.
      • Hawkins J.A.
      • Sower C.T.
      • et al.
      Right ventricle-to-pulmonary artery conduit longevity: is it related to allograft size?.
      • Karamlou T.
      • Ungerleider R.M.
      • Alsoufi B.
      • et al.
      Oversizing pulmonary homograft conduits does not significantly decrease allograft failure in children.
      For children, adolescents, and adults, the options for prosthesis include synthetic conduits, stented prosthetic valves, and homografts. For larger conduits (>19 mm) durability of the prosthetic valve within a Dacron conduit appears to be superior to that of homografts.
      • Zubairi R.
      • Malik S.
      • Jaquiss R.D.
      • et al.
      Risk factors for prosthesis failure in pulmonary valve replacement.
      • Dearani J.A.
      • Danielson G.K.
      • Puga F.J.
      • et al.
      Late follow-up of 1095 patients undergoing operation for complex congenital heart disease utilizing pulmonary ventricle to pulmonary artery conduits.
      • Razzouk A.J.
      • Williams W.G.
      • Cleveland D.C.
      • et al.
      Surgical connections from ventricle to pulmonary artery Comparison of four types of valved implants.
      • Allen B.S.
      • El-Zein C.
      • Cuneo B.
      • et al.
      Pericardial tissue valves and Gore-Tex conduits as an alternative for right ventricular outflow tract replacement in children.
      Thus, implantation of a stented pericardial or porcine valve within the native outflow tract or conduit is the preferred method for this age group. There is very little data to suggest that valve type or method of implantation (native outflow vs Dacron conduit) impacts durability, although one study reported that a porcine valve within Dacron conduit was associated with accelerated deterioration compared with the pericardial or porcine valve implanted into native RVOT.
      • Zubairi R.
      • Malik S.
      • Jaquiss R.D.
      • et al.
      Risk factors for prosthesis failure in pulmonary valve replacement.

      Conclusion

      In summary, options for RVOT reconstruction vary by age group. Risk factors for early structural valve deterioration include young age at operation and non-Ross operation for most prostheses. In neonates and infants, aortic homografts are preferred only in patients with elevated pulmonary artery pressures. In older children and adults, prosthetic valve reconstruction is preferred over homograft. Conduit oversizing may be associated with accelerated valve deterioration, but further investigation is necessary to confirm this finding.

      References

        • McMullan D.M.
        • Oppido G.
        • Alphonso N.
        • et al.
        Evaluation of downsized homograft conduits for right ventricle-to-pulmonary artery reconstruction.
        J Thoracic Cardiovasc Surg. 2006; 132: 66-71
        • Boethig D.
        • Goerler H.
        • Westhoff-Bleck M.
        • et al.
        Evaluation of 188 consecutive homografts implanted in pulmonary position after 20 years.
        Eur J Cardiothorac Surg. 2007; 32: 133-142
        • Meyns B.
        • Jashari R.
        • Gewillig M.
        • et al.
        Factors influencing the survival of cryopreserved homografts.
        Eur J Cardiothorac Surg. 2005; 28 (discussion 216): 211-216
        • Niwaya K.
        • Knott-Craig C.J.
        • Lane M.M.
        • et al.
        Cryopreserved homograft valves in the pulmonary position: risk analysis for intermediate-term failure.
        J Thoracic Cardiovasc Surg. 1999; 117 (discussion 146-147): 141-146
        • Tweddell J.S.
        • Pelech A.N.
        • Frommelt P.C.
        • et al.
        Factors affecting longevity of homograft valves used in right ventricular outflow tract reconstruction for congenital heart disease.
        Circulation. 2000; 102: III130-III135
        • Askovich B.
        • Hawkins J.A.
        • Sower C.T.
        • et al.
        Right ventricle-to-pulmonary artery conduit longevity: is it related to allograft size?.
        Ann Thorac Surg. 2007; 84 (discussion 911-902): 907-911
        • Sierra J.
        • Christenson J.T.
        • Lahlaidi N.H.
        • et al.
        Right ventricular outflow tract reconstruction: what conduit to use?.
        Ann Thorac Surg. 2007; 84 (discussion 610-601): 606-610
        • Rodefeld M.D.
        • Ruzmetov M.
        • Turrentine M.W.
        • et al.
        Reoperative right ventricular outflow tract conduit reconstruction: risk analyses at follow up.
        J Heart Valve Dis. 2008; 17 (discussion 126): 119-126
        • Niemantsverdriet M.B.
        • Ottenkamp J.
        • Gauvreau K.
        • et al.
        Determinants of right ventricular outflow tract conduit longevity: a multinational analysis.
        Congenit Heart Dis. 2008; 3: 176-184
        • Bando K.
        • Danielson G.K.
        • Schaff H.V.
        • et al.
        Outcome of pulmonary and aortic homografts for right ventricular outflow tract reconstruction.
        J Thoracic Cardiovasc Surg. 1995; 109 (discussion 517-508): 509-517
        • DeLeon S.Y.
        • Tuchek J.M.
        • Bell T.J.
        • et al.
        Early pulmonary homograft failure from dilatation due to distal pulmonary artery stenosis.
        Ann Thorac Surg. 1996; 61 (discussion 236-237): 234-236
        • Levine J.C.
        • Mayer Jr, J.E.
        • Keane J.F.
        • et al.
        Anastomotic pseudoaneurysm of the ventricle after homograft placement in children.
        Ann Thorac Surg. 1995; 59: 60-66
        • Konuma T.
        • Devaney E.J.
        • Bove E.L.
        • et al.
        Performance of CryoValve SG decellularized pulmonary allografts compared with standard cryopreserved allografts.
        Ann Thorac Surg. 2009; 88 (discussion 554-845): 849-854
        • Burch P.T.
        • Kaza A.K.
        • Lambert L.M.
        • et al.
        Clinical performance of decellularized cryopreserved valved allografts compared with standard allografts in the right ventricular outflow tract.
        Ann Thorac Surg. 2010; 90 (discussion 1306): 1301-1305
        • Baskett R.J.
        • Nanton M.A.
        • Warren A.E.
        • et al.
        Human leukocyte antigen-DR and ABO mismatch are associated with accelerated homograft valve failure in children: implications for therapeutic interventions.
        J Thoracic Cardiovasc Surg. 2003; 126: 232-239
        • Hartz R.S.
        • Deleon S.Y.
        • Lane J.
        • et al.
        Medtronic freestyle valves in right ventricular outflow tract reconstruction.
        Ann Thorac Surg. 2003; 76: 1896-1900
        • Schreiber C.
        • Sassen S.
        • Kostolny M.
        • et al.
        Early graft failure of small-sized porcine valved conduits in reconstruction of the right ventricular outflow tract.
        Ann Thorac Surg. 2006; 82: 179-185
        • Kim W.H.
        • Min S.K.
        • Choi C.H.
        • et al.
        Follow-up of Shelhigh porcine pulmonic valve conduits.
        Ann Thorac Surg. 2007; 84: 2047-2050
        • Erez E.
        • Tam V.K.
        • Doublin N.A.
        • et al.
        Repeat right ventricular outflow tract reconstruction using the Medtronic Freestyle porcine aortic root.
        J Heart Valve Dis. 2006; 15: 92-96
        • Kanter K.R.
        • Fyfe D.A.
        • Mahle W.T.
        • et al.
        Results with the freestyle porcine aortic root for right ventricular outflow tract reconstruction in children.
        Ann Thorac Surg. 2003; 76 (discussion 1894-1885): 1889-1894
        • Shebani S.O.
        • McGuirk S.
        • Baghai M.
        • et al.
        Right ventricular outflow tract reconstruction using Contegra valved conduit: natural history and conduit performance under pressure.
        Eur J Cardiothorac Surg. 2006; 29: 397-405
        • Brown J.W.
        • Ruzmetov M.
        • Rodefeld M.D.
        • et al.
        Valved bovine jugular vein conduits for right ventricular outflow tract reconstruction in children: an attractive alternative to pulmonary homograft.
        Ann Thorac Surg. 2006; 82: 909-916
        • Sekarski N.
        • van Meir H.
        • Rijlaarsdam M.E.
        • et al.
        Right ventricular outflow tract reconstruction with the bovine jugular vein graft: 5 years' experience with 133 patients.
        Ann Thorac Surg. 2007; 84: 599-605
        • Bautista-Hernandez V.
        • Kaza A.K.
        • Benavidez O.J.
        • et al.
        True aneurysmal dilatation of a Contegra conduit after right ventricular outflow tract reconstruction: a novel mechanism of conduit failure.
        Ann Thorac Surg. 2008; 86: 1976-1977
        • Lurz P.
        • Gaudin R.
        • Taylor A.M.
        • et al.
        Percutaneous pulmonary valve implantation.
        Semin Thoracic Cardiovasc Surg Pediatr Card Surg Annu. 2009; 11: 112-117
        • McElhinney D.B.
        • Hellenbrand W.E.
        • Zahn E.M.
        • et al.
        Short- and medium-term outcomes after transcatheter pulmonary valve placement in the expanded multicenter US melody valve trial.
        Circulation. 2010; 122: 507-516
        • Homann M.
        • Haehnel J.C.
        • Mendler N.
        • et al.
        Reconstruction of the RVOT with valved biological conduits: 25 years experience with allografts and xenografts.
        Eur J Cardiothorac Surg. 2000; 17: 624-630
        • Kobayashi J.
        • Backer C.L.
        • Zales V.R.
        • et al.
        Failure of the Hemashield extension in right ventricle-to-pulmonary artery conduits.
        Ann Thorac Surg. 1993; 56: 277-281
        • Agarwal K.C.
        • Edwards W.D.
        • Feldt R.H.
        • et al.
        Pathogenesis of nonobstructive fibrous peels in right-sided porcine-valved extracardiac conduits.
        J Thoracic Cardiovasc Surg. 1982; 83: 584-589
        • Dos L.
        • Munoz-Guijosa C.
        • Mendez A.B.
        • et al.
        Long term outcome of mechanical valve prosthesis in the pulmonary position.
        Int J Cardiol. 2011; 150: 173-176
        • Waterbolk T.W.
        • Hoendermis E.S.
        • den Hamer I.J.
        • et al.
        Pulmonary valve replacement with a mechanical prosthesis.
        Eur J Cardiothorac Surg. 2006; 30: 28-32
        • Haas F.
        • Schreiber C.
        • Horer J.
        • et al.
        Is there a role for mechanical valved conduits in the pulmonary position?.
        Ann Thorac Surg. 2005; 79 (discussion 1667-1668): 1662-1667
        • Rahimtoola S.H.
        Choice of prosthetic heart valve in adults an update.
        J Am Coll Cardiol. 2010; 55: 2413-2426
        • Zubairi R.
        • Malik S.
        • Jaquiss R.D.
        • et al.
        Risk factors for prosthesis failure in pulmonary valve replacement.
        Ann Thorac Surg. 2011; 91: 561-565
        • Albert J.D.
        • Bishop D.A.
        • Fullerton D.A.
        • et al.
        Conduit reconstruction of the right ventricular outflow tract.
        J Thoracic Cardiovasc Surg. 1993; 106 (discussion 235-226): 228-235
        • Hickey E.J.
        • McCrindle B.W.
        • Blackstone E.H.
        • et al.
        Jugular venous valved conduit (Contegra) matches allograft performance in infant truncus arteriosus repair.
        Eur J Cardiothorac Surg. 2008; 33: 890-898
        • Karamlou T.
        • Ungerleider R.M.
        • Alsoufi B.
        • et al.
        Oversizing pulmonary homograft conduits does not significantly decrease allograft failure in children.
        Eur J Cardiothorac Surg. 2005; 27: 548-553
        • Dearani J.A.
        • Danielson G.K.
        • Puga F.J.
        • et al.
        Late follow-up of 1095 patients undergoing operation for complex congenital heart disease utilizing pulmonary ventricle to pulmonary artery conduits.
        Ann Thorac Surg. 2003; 75 (discussion 410-391): 399-410
        • Razzouk A.J.
        • Williams W.G.
        • Cleveland D.C.
        • et al.
        Surgical connections from ventricle to pulmonary artery.
        Circulation. 1992; 86: II154-II158
        • Allen B.S.
        • El-Zein C.
        • Cuneo B.
        • et al.
        Pericardial tissue valves and Gore-Tex conduits as an alternative for right ventricular outflow tract replacement in children.
        Ann Thorac Surg. 2002; 74: 771-777
        • Brown J.W.
        • Ruzmetov M.
        • Rodefeld M.D.
        • et al.
        Right ventricular outflow tract reconstruction with an allograft conduit in non-ross patients: risk factors for allograft dysfunction and failure.
        Ann Thorac Surg. 2005; 80 (discussion 663-654): 655-663
        • Brown J.W.
        • Ruzmetov M.
        • Fukui T.
        • et al.
        Fate of the autograft and homograft following Ross aortic valve replacement: reoperative frequency, outcome, and management.
        J Heart Valve Dis. 2006; 15 (discussion 259-260): 253-259