In this study, we aimed to determine the incidence of reintervention and calcification of xenografts in paediatric patients who underwent placement of the right ventricle-to-pulmonary artery valved conduits. We retrospectively analysed clinical data of paediatric patients (1 day–18 years) who underwent right ventricular outflow tract reconstruction using xenograft from 2000 to 2016 at a single centre. A total of 301 patients underwent the placement of 337 xenografts, including glutaraldehyde-treated bovine jugular vein (n = 171, 50.7%), glutaraldehyde-treated bovine pericardial valved conduit (n = 75, 22.3%), diepoxy-treated porcine aortic conduit (n = 58, 17.2%) and diepoxy-treated bovine pericardial valved conduit (DE-PVC) (n = 33, 9.8%). There were 284 (84.3%) primary implantations and 53 (15.7%) reimplantations. The median follow-up was 4.2 years (range 1.5 months–14.5 years). The multivariate regression analysis did not reveal statistically significant associations of the first reintervention with the type of xenograft (P = 0.78). At reintervention, calcification of the wall and/or cusps was the main cause of conduit dysfunction in 66.4% of cases. On the basis of the multivariate Cox regression analysis, xenograft types were significant predictors of reintervention caused by conduit calcification (P = 0.012). The diepoxy-treated porcine aortic conduit group had the risk of calcification 3 times higher than the glutaraldehyde-treated bovine jugular vein group (P < 0.001).The glutaraldehyde-treated bovine pericardial valved conduit and diepoxy-treated bovine pericardial valved conduit groups had the risk of calcification comparable with the glutaraldehyde-treated bovine jugular vein group in multivariate proportional hazards model (P = 0.36 and P = 0.59, respectively). We have not revealed significant difference in the freedom from first reintervention among types of conduit. Calcification leading to the conduit dysfunction was present in all groups; however, diepoxy-treated porcine aortic conduits demonstrated suboptimal results in terms of calcification at follow-up.

Xenografts used for right ventricular outflow tract (RVOT) reconstruction are typically treated with glutaraldehyde. However, potential benefit of epoxy treatment was demonstrated in experimental studies. We aimed to compare diepoxy-treated bovine pericardial valved conduits (DE-PVCs) and glutaraldehyde-treated bovine pericardial valved conduits (GA-PVCs) for RVOT reconstruction in pediatric patients. Between 2002 and 2017, 117 patients underwent RVOT reconstruction with PVC in single center: DE-PVC group, n = 39; and GA-PVC group, n = 78. After performing propensity score analysis (1:1) for the entire sample, 29 patients from the DE-PVC group were matched with 29 patients from the GA-PVC group. There were no conduit-related deaths. In the DE-PVC group, the freedom from conduit failure was 90.9% at four years and 54.3% at eight years postoperatively. In the GA-PVC group, it was 46.3% and 33.1%, respectively. The difference was significant (P = .037). Conduit failure was typically caused by stenosis in both groups. In the DE-PVC group, the main cause of stenosis was xenograft calcification (27.6%); while in the GA-PVC group, it was mostly due to neointimal proliferation (25.0%) and, less often, calcification (14.3%). Conduit thrombosis was the cause of replacement in 6.9% of patients from the GA-PVC group. Diepoxy-treated bovine pericardial valved conduit is a suitable alternative to GA-PVC for RVOT reconstruction in pediatric patients. Diepoxy-treated bovine pericardial valved conduits may be less prone to conduit failure and more resistant to neointimal proliferation and conduit thrombosis than GA-PVCs.

Bidirectional cavopulmonary anastomosis (BCPA) is an important preliminary step toward the Fontan procedure; thus, understanding of risk factors for morbidity and mortality after BCPA may ultimately promote improved rates of success with Fontan completion and general survival. This study evaluated survival and predictors of unfavorable outcomes in patients after BCPA. Clinical data of 157 patients who underwent BCPA from 2003 to 2015 at a single center were retrospectively analyzed. Three-year and nine-year survival after BCPA were 87.1% ± 2.8% and 85.8% ± 2.9%, respectively. Freedom from unfavorable outcomes (mortality, BCPA takedown, nonsuitability for Fontan procedure) was 83.8% ± 3.1% at three years and 73.5% ± 4.8% at nine years. Multivariate proportional hazards regression analysis revealed that total anomalous pulmonary venous connection (TAPVC; hazard ratio [HR]: 3.74, 95% confidence interval [CI]: 1.35-10.36; P = .01) and increased mean pressure in BCPA circuit (HR: 1.17, 95% CI: 1.02-1.34; P = .03) were independent risk factors for unfavorable outcomes. Postoperative mean pressure in BCPA circuit in patients with poor outcomes was median 16 mm Hg (interquartile range [IQR]: 14-18 mm Hg) versus median 14 mm Hg (IQR: 12-15.5 mm Hg) in patients with favorable outcomes (P < .01). Preoperative (HR: 1.87, 95% CI: 1.20-2.91; P < .01) and postoperative atrioventricular valve regurgitation (AVVR; HR: 2.22, 95% CI: 1.24-3.94; P < .01) were also associated with unfavorable outcome in univariate Cox regression. Elevated mean pressure in the BCPA circuit is the main predictor of unfavorable outcome; therefore, thorough preoperative examination and careful patient selection are critical points for successful intermediate-stage and later Fontan completion. Total anomalous pulmonary venous connection and insufficient correction of AVVR worsen the prognosis in this patient group.

OBJECTIVES: This study aimed to evaluate the influence of preserved additional pulmonary blood flow (APBF) on survival after bidirectional cavopulmonary shunt (BCPS) and completion of Fontan circulation. METHODS: From March 2003 and April 2015, 156 patients with a single ventricle underwent BCPS. After performing propensity score analysis (1:1) for the entire sample, 50 patients with APBF (APBF group) were matched with 50 patients without APBF (no-APBF group). RESULTS: Age (P = 0.90), sex (P = 0.57), weight (P = 0.75), single ventricle morphology (P = 0.87), type of neonatal palliative procedure (P = 0.52), saturation (P = 0.35), ejection fraction (P = 0.90), Nakata index (P = 0.70) and mean pulmonary artery pressure (P = 0.72) were not significantly different between the groups. No significant survival difference was demonstrated (P = 0.54). One and 4-year survival rates were both 89.1% ± 4.6% in the APBF group and 87.2% ± 4.9% and 83.4% ± 5.9%, respectively, in the no-APBF group. There was no significant difference in rates of Fontan completion (P = 0.24), which was achieved in 22 patients from the APBF group (55.0%) and 26 patients from the no-APBF group (65.0%). However, Fontan completion occurred significantly earlier in the no-APBF group (P < 0.01). In this group, Fontan procedure was performed before 36 months of inter-stage period in 45.9% ± 8.5% of cases (95% CI 31.0–63.7%) compared to only 13.3 ± 5.6% (95% CI 5.8–29.1%) in the APBF group. CONCLUSIONS: Our study demonstrates that APBF does not affect survival after BCPS or Fontan completion rate. APBF allows postponing the Fontan procedure without a negative effect on clinical status.

Клинико-морфологический анализ дисфункции кондуита Contegra у пациентов первого года жизни

Valved conduits are often required to replace pulmonary arteries (PA). A widely used Contegra device is made of bovine jugular vein (BJV), preserved with glutaraldehyde (GA) and iso-propanol. However, it has several drawbacks that may be attributed to its chemical treatment. We hypothesized that the use of an alternative preservation compound may significantly improve BJV conduit performance. This study aimed to compare the macroscopic and microscopic properties of the BJV treated with diepoxide (DE) and GA in a porcine model. Twelve DE-BJVs and four Contegra conduits were used for PA replacement in minipigs. To assess the isolated influence of GA, we included an additional control group—BJV treated with 0.625% GA (n = 4). The animals were withdrawn after 6 months of follow-up and the conduits were examined. Explanted DE-BJV had a soft elastic wall with no signs of thrombosis or calcification and good conduit integration, including myofibroblast germination, an ingrowth of soft connective tissue formations and remarkable neoangiogenesis. The inner surface of DE-BJVs was covered by a thin neointimal layer with a solid endothelium. Contegra grafts had a stiffer wall with thrombosis on the leaflets. Calcified foci, chondroid metaplasia, and hyalinosis were observed within the wall. The distal anastomotic sites had hyperplastic neointima, partially covered with the endothelium. The wall of GA-BJV was stiff and rigid with degenerative changes, a substantial amount of calcium deposits and dense fibrotic formations in adventitia. An irregular neointimal layer was presented in the anastomotic sites without endothelial cover in the GA BJV wall. These results demonstrate that DE treatment improves conduit integration and the endothelialization of the inner surface while preventing the mineralization of the BJV, which may reduce the risk of early conduit dysfunction.