Total repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals: An integrated approach

AbstractBackground: Predicting postrepair right ventricular/left ventricular pressure ratio has prognostic relevance for patients undergoing total repair of pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries. To this purpose, we currently rely on 2 novel parameters: (1) preoperative total neopulmonary arterial index and (2) mean pulmonary artery pressure changes during an intraoperative flow study. Methods: Since January 1994, 15 consecutive patients (aged 64 ± 54 months) with pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals were managed according to total neopulmonary arterial index. Seven patients with hypoplastic pulmonary arteries and a total neopulmonary arterial index less than 150 mm2/m2 underwent palliative right ventricular outflow tract reconstruction followed by secondary 1-stage unifocalization and ventricular septal defect closure. The other 8 patients with a preoperative index of more than 150 mm2/m2 underwent primary single-stage unifocalization and repair. The ventricular septal defect was closed in all cases (reopened in 1). In 9, such decision was based on an intraoperative flow study. Results: Patients treated by right ventricular outflow tract reconstruction had a significant increase of pulmonary artery index (P = .006) within 22 ± 6 months. Repair was successful in 14 cases (postrepair right ventricular/left ventricular pressure ratio = 0.47 ± 0.1). One hospital death occurred as a result of pulmonary vascular obstructive disease, despite a reassuring intraoperative flow study. Accuracy of this test in predicting the postrepair mean pulmonary artery pressure was 89% (95% CI: 51%-99%). At follow-up (18 ± 12 months), all patients are free of symptoms, requiring no medications. Conclusion: The integrated approach to total repair of pulmonary atresia, ventricular septal defect, and major aortopulmonary collaterals by preoperative calculation of total neopulmonary arterial index, right ventricular outflow tract reconstruction (when required), and intraoperative flow study may lead to optimal intermediate results. (J Thorac Cardiovasc Surg 1998;116:914-23

Airway Complications after Single-Stage Unifocalization for Pulmonary Atresia,Ventricular Septal Defect, and Major Aortopulmonary Collateral Arteries

Objective: We analyze the incidence of postoperative severe airflow limitation after single-stage unifocalization in patients with pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries (PA/VSD/ MAPCAs) and comment on the treatment performed. Methods: From 1994 until 2012, 106 patients with diagnosis of PA, VSD, MAPCAs underwent surgical treatment. Four of them (3.8%) developed in the postoperative course severe airflow complication. Chromosome 22q11 deletion was present in three of them. Median age at the time of unifocalization was 6.2 months (range 21 days – 11 months). Results: The first developed malacia and compression of the left bronchus from the distal RV-PA conduit treated with external bronchial stenting with two incomplete costal cartilage rings. The second patient developed recurrent esophagus-left bronchus fistula treated with multiple surgical esophageal and bronchus reconstruction. The third child presented bilateral bronchial malacia treated with bilateral stenting and after with surgical elongation of the neo-left pulmonary artery to avoid external compression. The last developed bilateral bronchomalacia treated with bilateral bronchial stenting and after with RV-PA conduit replacement and endobronchial stenting calibration Conclusion: Particular categories of patients (22q11 chromosome deletion, neonates/infants, patients with dominant/exclusive collaterals,) may be more predisposed to develop airway limitation. The treatment of the lesion should be individualized according to the supposed pathogenic mechanism. We suggest endoluminal treatment in absence of compression by vascular structures while surgery was used in proven case of extrinsic compression

Risk Factors of Right Ventricular Dysfunction and Adverse Cardiac Events in Patients with Repaired Tetralogy of Fallot

Aim: This study evaluates the risk factors associated with right ventricular (RV) dilation and dysfunction leading to pulmonary valve replacement (PVR) or adverse cardiac events in repaired Tetralogy of Fallot (rToF) patients. Methods: Data from all rToF patients who underwent magnetic resonance imaging (MRI) evaluation at our hospital between February 2007 and September 2020 were collected. Results: Three hundred and forty-two patients (60% males, 42% older than 18 years), with a median age of 16 years (IQR 13–24) at the time of MRI, were included. All patients underwent complete repair at a median age of 8 months (IQR 5–16), while palliation was performed in 56 patients (16%). One hundred and forty-four patients (42%) subsequently received pulmonary valve replacement (PVR). At the multivariate analysis, male gender was an independent predictor for significant RV dilation, RV and left ventricular (LV) dysfunction. Transventricular ventricular septal defect (VSD) closure and previous palliation significantly affected LV function and RV size, respectively. Male gender and the transventricular VSD closure were independent predictors for PVR. Conclusions: Male gender and surgical history (palliation, VSD closure approach) significantly affected the long-term outcomes in rToF patients and should be taken into consideration in the follow-up management and in PVR timing in this patient population

Surgical Atrioventricular Valve Replacement With Melody Valve in Infants and Children

Background Pediatric patients with atrioventricular valve disease have limited options for prosthetic valve replacement in sizes <15 mm. Based on successful experience with the stented bovine jugular vein graft (Melody valve) in the right ventricular outflow tract, the prosthesis has been modified for surgical valve replacement in pediatric patients with atrioventricular dysfunction with the intention of subsequent valve expansion in the catheterization laboratory as the child grows. Methods and Results A multicenter, retrospective cohort study was performed among patients who underwent atrioventricular valve replacement with Melody valve at 17 participating sites from North America and Europe, including 68 patients with either mitral (n=59) or tricuspid (n=9) replacement at a median age of 8 months (range, 3 days to 13 years). The median size at implantation was 14 mm (range, 9-24 mm). Immediately postoperatively, the valve was competent with low gradients in all patients. Fifteen patients died; 3 patients underwent transplantation. Nineteen patients required reoperation for adverse outcomes, including valve explantation (n=16), left ventricular outflow tract obstruction (n=1), permanent pacemaker implantation (n=1), and paravalvular leak repair (n=1). Twenty-five patients underwent 41 episodes of catheter-based balloon expansion, exhibiting a significant decrease in median gradient ( P<0.001) with no significant increase in grade of regurgitation. Twelve months after implantation, cumulative incidence analysis indicated that 55% of the patients would be expected to be free from death, heart transplantation, structural valve deterioration, or valve replacement. Conclusions The Melody valve is a feasible option for surgical atrioventricular valve replacement in patients with hypoplastic annuli. The prosthesis shows acceptable short-term function and is amenable to catheter-based enlargement as the child grows. However, patients remain at risk for mortality and structural valve deterioration, despite adequate early valvular function. Device design and implantation techniques must be refined to reduce complications and extend durability. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT02505074

Thymic Epithelium Abnormalities in DiGeorge and Down Syndrome Patients Contribute to Dysregulation in T Cell Development

The thymus plays a fundamental role in establishing and maintaining central and peripheral tolerance and defects in thymic architecture or AIRE expression result in the development of autoreactive lymphocytes. Patients with partial DiGeorge Syndrome (pDGS) and Down Syndrome (DS) present alterations in size and architecture of the thymus and higher risk to develop autoimmunity. We sought to evaluate thymic architecture and thymocyte development in DGS and DS patients and to determine the extent to which thymic defects result in immune dysregulation and T cell homeostasis perturbation in these patients. Thymi from pediatric patients and age-matched controls were obtained to evaluate cortex and medullary compartments, AIRE expression and thymocyte development. In the same patients we also characterized immunophenotype of peripheral T cells. Phenotypic and functional characterization of thymic and peripheral regulatory T (Treg) cells was finally assessed. Histologic analysis revealed peculiar alterations in thymic medulla size and maturation in DGS and DS patients. Perturbed distribution of thymocytes and altered thymic output was also observed. DGS patients showed lower mature CD4+ and CD8+ T cell frequency, associated with reduced proportion and function of Tregs both in thymus and peripheral blood. DS patients showed increased frequency of single positive (SP) thymocytes and thymic Treg cells. However, Tregs isolated both from thymus and peripheral blood of DS patients showed reduced suppressive ability. Our results provide novel insights on thymic defects associated with DGS and DS and their impact on peripheral immune dysregulation. Indeed, thymic abnormalities and defect in thymocyte development, in particular in Treg cell number and function could contribute in the pathogenesis of the immunodysregulation present in pDGS and in DS patients

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