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OBJECTIVES The right ventricle-to-pulmonary artery (RV-PA) shunt provides stable haemodynamics after the Norwood procedure but can influence development of the central pulmonary arteries (PAs). The goal of this study was to analyse the geometry of the central PAs in children with hypoplastic left heart syndrome before the Fontan operation with respect to the RV-PA shunt site and the type of the second-stage operation. METHODS A total of 161 children with hypoplastic left heart syndrome, median age 2.7 (range 1.3–9.8) years and median weight 12.7 (range 7.6–26.1) kg, underwent the Fontan operation after having had the Norwood procedure with an RV-PA shunt. The patients were divided into 2 groups: left-sided RV-PA (L-RV-PA) (n = 129) with the shunt on the left and right-sided RV-PA (n = 32) with the shunt on the right side of the neoaorta. Angiographic data obtained before the Fontan and all cardiac catheterization interventions were analysed retrospectively. RESULTS Between the second and third stages, as well as directly before the Fontan operation, the L-RV-PA group required more PA catheter interventions (P = 0.001 and P = 0.03). In this group, the minimal left PA diameter was smaller than that in the R-RV-PA group (P = 0.021). Leaving the shunt open until the Fontan operation increased the rate of PA interventions in the L-RV-PA group (P = 0.001), but there is no evidence of the impact on the development of the left PAs (P = 0.075). There is also no evidence that the type of the second-stage procedure influences the intervention rate before the Fontan procedure (P = 0.14). CONCLUSIONS Children who have the L-RV-PA shunt require more PA catheter interventions. The right-sided RV-PA shunt and the subsequent Glenn anastomosis in the place of the shunt are associated with distortion-free and more symmetrical development of the central PAs.

OBJECTIVES Currently, Contegra® grafts (processed bovine jugular vein conduits) are widely used for reconstructive surgery of the right ventricular outflow tract in patients with congenital heart disease (CHD). We analysed explanted Contegra conduits from 2 institutions histologically to get a possible hint at the underlying pathomechanisms of degenerative alterations and to find histological correlations of graft failure. Additionally, we compared the explants with a non-implanted processed graft and a native jugular vein obtained from a young bull. METHODS The explanted Contegra grafts were gathered during reoperations of 13 patients (male: n = 9, 69.2%; female: n = 4, 30.8%). After standardized histological preparation, samples were stained with dyes haematoxylin and eosin and Elastica van Gieson. Additionally, X-ray pictures revealed the extent of calcification and chelaplex (III)-descaling agent was used to decalcify selected explants. RESULTS Processing of the native jugular vein leads to tissue loosening and a loss of elastic fibres. For graft failure after implantation, 2 pathomechanisms were identified: original graft alteration as well as intimal hyperplasia. Elastica degeneration and rearrangement with interfibrillary matrix structures were the main developments observed within the graft itself. Intimal hyperplasia was characterized by fibrous tissue apposition, calcification and heterotopic ossification. CONCLUSIONS Regression of the elastic fibre network leads to rigidification of the conduit. In Contegra grafts, atherosclerosis-like changes can be considered the leading cause of graft stenosis and insufficiency. We conclude that both observed mechanisms lead to early reoperation in CHD patients.

Objective: The operative outcome of the Norwood procedure for hypoplastic left heart syndrome is still not satisfactory. Conflicting reports concern factors associated with early Norwood procedure mortality and the reasons for the instability after surgery are not sufficiently understood. The purpose of this study was to determine some perioperative factors influencing early (30 days) outcome. Methods :W e retrospectively analyzed a group of 30 consecutive children with hypoplastic left heart syndrome (aged 5‐39 days) who underwent Norwood procedure in 1997 and 1998. The following factors were considered and statistically analyzed: operative age, birth weight, operative weight, serum level of bilirubin, aminotransferases, creatinine, urea, arterial blood gasses, anatomic subgroups, ascending aorta and arch size, systemic to pulmonary modified right Blalock‐Taussig shunt size, cardiopulmonary circulatory arrest time, cardiopulmonary bypass time, and delayed chest closure. Eighteen patients underwent hemi-Fontan procedure with one late death and the modified Fontan operation was performed in 16 of them (one late death). Results: The early mortality was 37%. Seven deaths (64%) occurred during the first 24 h after operation. There was a significant difference between survivals and non-survivals in: birth weight (Pa 0:047), operative age (Pa 0:016), preoperative serum level of bilirubin (Pa 0:044), and cardiopulmonary circulatory arrest time (Pa 0:006). The other assessed factors were not found to be predictors of early mortality. All 16 survivals followed up are in New York Heart Association class I or II. Conclusions: Anatomic and functional status of the patient, as well as procedural factors are related to Norwood operation early mortality. High mortality in hypoplastic left heart syndrome after stage I surgery indicates the necessity of assessing all factors which may determine further improvement in the outcome. q 2000 Elsevier Science B.V. All rights reserved.