There are no graft specific non-conformances (ncs) associated with cryopatch synergraft pulmonary hemi-artery (sgph00), serial identification number (sid) (b)(6).There are no ncs associated with the transfer or handling of this allograft.No deviations were identified during a review of the tissue transfer logs or the packaging inspection sheet.The graft was implanted in a 0.01-year-old female patient on (b)(6) 2019 and used to reconstruct the patient¿s hypoplastic aortic arch as part of the norwood procedure.The patient subsequently required reintervention and partial patch repair of the aortic arch due to stenosis on (b)(6) 2019, almost 2 months after the original procedure.The norwood procedure is the first stage of a 3-part surgical palliation procedure to correct hypoplastic left heart syndrome (hlhs).Hypoplastic left heart syndrome (hlhs) constitutes a spectrum of cardiac anomalies that result in underdevelopment of left-sided heart structures.It is characterized by underdevelopment of the aorta, aortic valve, left ventricle, mitral valve, and left atrium, resulting in severe or total obstruction of blood flow from the left ventricle.(sivanandam 2011).Coarctation of the aorta (narrowing of the aorta) is the most frequently associated anomaly with hlha, and it may impede retrograde blood flow to a diminutive ascending aorta (atik 2006).Without some form of intervention, hlhs is universally fatal within the first weeks of life and is the most common cause of cardiac-related death in children less than one month of age.The goals of norwood procedure are to relieve systemic outflow tract obstruction, provide nonrestrictive coronary blood flow and adequate pulmonary blood flow, and create a nonrestrictive atrial septal defect (feinstein 2012).The norwood palliation of hlhs includes constructing a neo-aorta utilizing the pulmonary root, ascending aorta, and cryopreserved homograft tissue (the patch material).The ductal tissue is resected and the augmentation of the aortic arch and site of coarctation is carried out.Pulmonary blood flow is provided by placement of a shunt.The norwood procedure is performed shortly after birth within the first week of life.The second procedure, known as the bi-directional glenn or hemi-fontan, is performed between 3-6 months of age, and the final stage, known as the fontan, between 18 months ¿ 5 years of age.Recoarctation of the neoaorta is widely recognized as a common complication after the norwood procedure, with rates from the literature ranging from 11% to 37% (ashcraft 2008, cleuziou 2013, sakurai 2012, ballweg 2010, feinstein 2012, fraisse 1998, porras 2011).Several studies have attempted to identity preoperative (patient) and intraoperative (surgical technique) risk factors associated with recoarctation of the aorta following the norwood procedure (ashcraft 2008, cleuziou 2013, sakurai 2012, ballweg 2010, feinstein 2012, fraisse 1998, porras 2011).However, the association of pre-operative (patient-related) and intra-operative (technique related) risk factors predisposing a patient to recoarctation after the norwood procedure have not been well characterized and are not well understood (ashcraft 2008, cleuziou 2013).For example, a retrospective review of 124 norwood patients by cleuziou et al.Was unable to identify any independent risk factors related to recoarctation (cleuziou 2013).Additional studies have also tried to identify risk factors associated with recoarctation.A study of 117 norwood patients by ashcraft et al., reported that age, gender, weight, ascending aortic diameter, ventricular morphology, primary anatomic diagnosis, and incomplete coarctation shelf resection were not significant predictors of recoarctation or reintervention, while a report of 289 norwood patients by sakurai et al., demonstrated size of ascending aorta and incomplete resection of coarctation tissue, to be significant risk factors for recoarctation (ashcraft 2008, sakurai 2011).Similarly, ashcraft et al.Reported that, although not statistically significant (p= 0.09), the use of bovine pericardium trended toward an increased risk of recoarctation over time compared with the use of pulmonary artery homograft (ashcraft 2008).The reconstructed neoaorta may display dramatic caliber changes through the arch, which may increase the chance of kinks or folds in the patched neoaorta (ashcraft 2008).Differing surgical techniques have evolved over the years in an attempt to reduce the incidence of recoarctation (ashcraft 2008, feinstein 2011).It is well recognized that even mild anatomic obstruction of the neoaorta can have significant deleterious impact.The indication for re-intervention or reoperation for recoarctation secondary to pressure changes or increased neoaortic gradient varies from center to center.However, because of the risks associated with a single ventricle, the majority of centers have uniformly adopted a low threshold for reintervention in the event of recoarctation or residual stenosis after the norwood procedure (ashcraft 2008, porras 2011).In addition, there is still no uniform, or definitive measurement that defines a clinically significant obstruction, therefore, any positive gradient constitutes obstruction, which may impair ventricular function (walters 2013).The report states that the surgeon had to trim the allograft around multiple ¿tears¿ and ¿stretch the tissue into place.¿ this suggests that the size of the implanted patch may have been smaller than optimal for the intended application.Consequently, the degree of aortic augmentation may have been limited leading to an increased risk of restenosis.It is important to note that use of the sgph00 in norwood procedures is considered off-label, as the sgph00 is indicated for the repair or reconstruction of the right ventricular outflow tract (cryopatch ifu).Because use in the norwood is off-label, there is very limited data available in the literature.One publication by knepp at el.(2011) was identified that describes the off-label use of sg hemi patch material in 14 neonates undergoing aortic arch reconstruction as part of the norwood procedure; there were no patch related adverse events reported.The root cause of the reported event is unknown; however, the implanted patch may have been too small for the intended application due to extensive trimming of the allograft.Consequently, the aortic augmentation may have been limited, increasing the risk of restenosis.Stenosis is a known complication associated with the use of sg patch and is included in the ifu.This report is being submitted as required by federal regulations and does not constitute an admission that the device caused or contributed to the reported event.Furthermore, this report reflects the event as alleged by the complainant and does not imply that the information reported to cryolife is accurate or has been confirmed by cryolife.
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