Pediatric airway compression in aortic arch malformations: a multidisciplinary approach.

Background: Aortic arch malformations (AAMs) should be suspected in the presence of persistent respiratory symptoms despite medical treatment or feeding problems at the pediatric age. Aim: We report a descriptive cohort of patients with AAMs and the local management protocol applied. Methods: A total of 59 patients with AAM were retrospectively reviewed. Three groups were identified: double aortic arch (DAA), group 1; complete vascular ring (non-DAA), group 2; and anomalous origin of the innominate artery (IA), group 3. Results: Prenatal diagnosis was available for 62.7% of the patients. In all, 49.2% of children were symptomatic. There was a significantly different prevalence of respiratory symptoms within the three groups: 73.7% in group 1, 24.2% in group 2, and 100% in group 3 (p-value: <0.001). Surgery was considered in the presence of symptoms in patients with DAA and in those with reduction of the tracheal section area greater than 50%. A total of 52.5% of the patients underwent surgical repair (median age 6 months). The median follow-up interval was 21.9 months. Respiratory symptoms improved in most symptomatic patients. Conclusions: No specific protocols are available for the management of patients with AAMs. Conservative treatment seems to be reasonable for asymptomatic patients or those with airway stenosis less than 50%. A close follow-up is necessary to identify early patients who become symptomatic.

Late outcome of extracardiac Fontan patients: 32 years of follow-up.

OBJECTIVES: We sought to evaluate the long-term survival and risk factors for morbidity and mortality in our cohort of patients after extracardiac (EC) Fontan. METHODS: We collected and analysed follow-up data until September 2020 for all patients who underwent EC Fontan operation at our institution from November 1988 to November 2015. RESULTS: Out of 406 patients treated with EC Fontan at a mean age of 5.4 ± 4.5 years, 372 (91.6%) were discharged home; 15% were lost to follow-up. The median follow-up was 14.6 years (interquartile range 8.7-20.3). Two hundred patients (54%) had a good long-term outcome, with an event-free long-term survival, but late adverse events of any kind needing interventional or surgical reoperations were reported in 128 patients (34%). Forty-four patients (12%) developed late Fontan failure. Thirty-seven survivors (10%) had late arrhythmias, with the need for pacemaker implantation. Obstruction of the cavopulmonary pathway occurred in 49 patients (13%), but just 8 patients needed conduit surgical replacement. At 32 years, the survival probability was 84%. The risk of orthotopic heart transplant, considering death as a competing event (showed as cumulative incidence), was 12.5%. A preoperative diagnosis of hypoplastic left heart syndrome was an independent risk factor for the need for heart transplant. CONCLUSIONS: The EC Fontan shows satisfactory long-term survival and low incidence of adverse events and late failure. Conduit replacement is rare, and its longevity may not represent a substantial issue in these patients. However, as with other technical variants, the need for reoperations during long-term follow-up is a significant challenge.

Pediatric aortic valve neocuspidization.

Treatment of pediatric aortic valve disease is controversial. In this regard, interest is growing in the neocuspidization of the aortic valve according to Ozaki. In this video tutorial, we illustrate briefly the entire reconstruction technique of a neoaortic valve with pretreated autologous pericardium used in our institution in pediatric patients by describing a case of an incompetent native tricuspid aortic valve.

Blood flow characteristics after aortic valve neocuspidization in paediatric patients: a comparison with the Ross procedure.

AIMS: The aortic valve (AV) neocuspidization (Ozaki procedure) is a novel surgical technique for AV disease that preserves the natural motion and cardiodynamics of the aortic root. In this study, we sought to evaluate, by 4D-flow magnetic resonance imaging, the aortic blood flow characteristics after AV neocuspidization in paediatric patients. METHODS AND RESULTS: Aortic root and ascending aorta haemodynamics were evaluated in a population of patients treated with the Ozaki procedure; results were compared with those of a group of patients operated with the Ross technique. Cardiovascular magnetic resonance studies were performed at 1.5 T using a 4D flow-sensitive sequence acquired with retrospective electrocardiogram-gating and respiratory navigator. Post-processing of 4D-flow analysis was performed to calculate flow eccentricity and wall shear stress. Twenty children were included in this study, 10 after Ozaki and 10 after Ross procedure. Median age at surgery was 10.7 years (range 3.9-16.5 years). No significant differences were observed in wall shear stress values measured at the level of the proximal ascending aorta between the two groups. The analysis of flow patterns showed no clear association between eccentric flow and the procedure performed. The Ozaki group showed just a slightly increased transvalvular maximum velocity. CONCLUSION: Proximal aorta flow dynamics of children treated with the Ozaki and the Ross procedure are comparable. Similarly to the Ross, Ozaki technique restores a physiological laminar flow pattern in the short-term follow-up, with the advantage of not inducing a bivalvular disease, although further studies are warranted to evaluate its long-term results.

Idiopathic Ventricular Fibrillation: Look for the Hidden Guilty-A case of aborted cardiac death.

We report a unique case of a 6-year-old male child with aborted sudden cardiac death due to ventricular fibrillation. A rare anomalous aortic origin of the right coronary artery was detected and supposed to be the cause of the malignant arrhythmia. Clinical exome sequencing did not reveal any pathogenic variant related to channelopathies nor other known heart-related genes. The patient underwent cardiac surgery and a cardiac defibrillator was implanted for secondary prevention.

Premature Senescence and Increased Oxidative Stress in the Thymus of Down Syndrome Patients.

Down syndrome (DS) patients prematurely show clinical manifestations usually associated with aging. Their immune system declines earlier than healthy individuals, leading to increased susceptibility to infections and higher incidence of autoimmune phenomena. Clinical features of accelerated aging indicate that trisomy 21 increases the biological age of tissues. Based on previous studies suggesting immune senescence in DS, we hypothesized that induction of cellular senescence may contribute to early thymic involution and immune dysregulation. Immunohistochemical analysis of thymic tissue showed signs of accelerated thymic aging in DS patients, normally seen in older healthy subjects. Moreover, our whole transcriptomic analysis on human Epcam-enriched thymic epithelial cells (hTEC), isolated from three DS children, which revealed disease-specific transcriptomic alterations. Gene set enrichment analysis (GSEA) of DS TEC revealed an enrichment in genes involved in cellular response to stress, epigenetic histone DNA modifications and senescence. Analysis of senescent markers and oxidative stress in hTEC and thymocytes confirmed these findings. We detected senescence features in DS TEC, thymocytes and peripheral T cells, such as increased ß-galactosidase activity, increased levels of the cell cycle inhibitor p16, telomere length and integrity markers and increased levels of reactive oxygen species (ROS), all factors contributing to cellular damage. In conclusion, our findings support the key role of cellular senescence in the pathogenesis of immune defect in DS while adding new players, such as epigenetic regulation and increased oxidative stress, to the pathogenesis of immune dysregulation.

Predictors of survival in paediatric mitral valve replacement.

OBJECTIVES: The aim of this study was to identify the predictors of death and of reintervention after mitral valve replacement (MVR) in children. METHODS: A single-centre retrospective study was performed including 115 patients under the age of 18 undergoing MVR between 1982 and 2019. For all patients, the ratio of prosthetic valve size (diameter in mm) to weight (kg) at surgery was calculated and long-term result was assessed. The primary outcome was freedom from mitral valve (MV) re-replacement. The composite secondary outcome was freedom from death or transplant. RESULTS: Fifty-four patients had a previous surgical attempt to MV repair. The median age at surgery was 5.5 years (interquartile range 1.21-9.87). Death/transplant-free survival was 77 ± 4% at 5 years and 72 ± 5% at 10 years. Univariate analysis showed a size/weight ratio higher than 2 and age <2 years as significant risk factors for death or transplant. Freedom from MV re-replacement at 5 and 10 years was 90 ± 3% and 72 ± 6%, respectively. Biological prosthesis implanted at first replacement (P = 0.007) and size/weight ratio higher than 2 (P = 0.048) were predictors of reoperation. Significant upsizing (P < 0.0001) of mitral prosthesis was observed at re-replacement. CONCLUSIONS: MVR is a viable strategy in children with unrepairable MV disease. Mortality can be predicted based on size/weight ratio and age <2 years. MV re-replacement can be performed with low morbidity and mortality and a larger-size prosthesis can often be placed at the time of redo.

Aortic Valve Neocuspidalization May Be a Viable Alternative to Ross Operation in Pediatric Patients.

The aim of the study was to evaluate the medium-term results of aortic valve neocuspidalization according to Ozaki compared to Ross procedure for treatment of isolated aortic valve disease in pediatric age. Thirty-eight consecutive patients with congenital or acquired aortic valve disease underwent either Ozaki (n = 22) or Ross (n = 16) operation between 01/2015 and 05/2020. The primary outcome was progression of aortic valve disease and aortic ring and root dimension, whereas secondary outcome was freedom from reintervention or death by type of operation. Median age was 12.4 (8.8-15.8) years and the prevailing lesion was stenosis in 20 cases (52%) and incompetence in 18 (48%). One death occurred in the Ross group in the early postoperative period, while there were no deaths in the Ozaki group. Effective treatment of aortic valve stenosis or regurgitation occurred in both groups and remained stable over a median follow-up of 18.2 (5-32) months. In Ozaki group, 3 patients required aortic valve replacement at 4.9, 3.5, and 33 months, respectively. In Ross group, 1 patient required Melody pulmonary valve replacement, whereas none required aortic valve surgery. Finally, significantly higher aortic transvalvular gradient at follow-up was recorded in Ozaki group compared to Ross group. Overall, there was no significant difference in freedom from reoperation or death between the two groups. The medium-term outcome of Ozaki and Ross in pediatric patients is similar, despite an increased tendency of the former to develop aortic transvalvular gradient in the follow-up. Future larger multicenter studies with longer follow-up are warranted to confirm these results.

Aortic valve neocuspidalization in paediatric patients with isolated aortic valve disease: early experience.

OBJECTIVES: There is growing interest in the aortic valve (AV) neocuspidalization technique for the treatment of aortic valve disease (AVD). We report our medium-term results with this procedure performed in a paediatric patient population. METHODS: Between July 2016 and May 2020, 22 patients with both congenital and acquired isolated AVD were treated with neocuspidalization. The primary outcome was progression of the preoperatively assessed AVD in the immediate postoperative course and at follow-up. Secondary outcome was freedom from reintervention by material used. Potential predictors of failure were analysed in relation to the primary outcome. RESULTS: The median age at operation was 13.9 (interquartile range, 9.8-16.2) years, and the prevailing AV defect was stenosis in 10 cases (45%) and incompetence in 12 (55%). Pre-treated autologous pericardium was used in 13 patients whereas bovine pericardium in 9. Effective treatment of AV stenosis or regurgitation was achieved and remained stable over a median follow-up of 11.3 (4.7-21) months. Three patients required AV replacement at 4.9, 3.5 and 33 months. At follow-up, an upward trend of both median indexed vena contracta jet widths and aortic peak and mean gradients were recorded, the latter associated with a failure to grow the aortic annulus. Predictor of such outcome turned out to be the use of bovine pericardium. A significant inverse linear correlation between AV peak gradient at follow-up and preoperative aortic annular size (P = 0.008) was also demonstrated. CONCLUSIONS: The Ozaki procedure is safe and effective in paediatric patients with AV disease. The use of heterologous pericardium should probably be minimized. Moreover, preoperative small aortic annuli should probably be promptly treated by means of an associated ring enlargement procedure.

Recurrent Wheezing in Pre-school Age: Not Only Airway Reactivity!

Background: About a fifth of all mediastinal masses are primary cysts arising in the absence of other underlying pathology. Bronchogenic cysts, although rare, are the most frequent type responsible for lower airways compression as they often develop in the peripheral branches of the tracheobronchial tree. Case presentation: We report the case of a 6-months-old child admitted for acute respiratory distress and wheezing not responsive to asthma treatment. Digestive and airway endoscopy proved a mild and a marked reduction of the esophageal and tracheal lumen, respectively. The nocturnal polygraphy showed an underlying obstructive disorder and the chest CT scan confirmed the presence of a wide mediastinal cyst compressing the trachea. The mass, later identified as a bronchogenic cyst, was surgically removed with complete resolution of the patient's respiratory symptoms. Discussion: Our case shows that differential diagnosis of wheezing in pre-school aged children should encompass causes others than airway reactivity, thus prompting further evaluation and management.

Surgical Management of Fallot's Tetralogy With Pulmonary Atresia and Major Aortopulmonary Collateral Arteries: Multistage Versus One-Stage Repair.

A strict and rational approach to Fallot's tetralogy with pulmonary atresia and major aortopulmonary collateral arteries allows to achieve optimal results. Rehabilitative and unifocalization strategies do not constitute separate philosophies; instead the surgical strategy should be tailored to each individual patient. Based on our previous experience, the ability to achieve definitive intracardiac repair is the real determinant of both improved survival and adequate systolic right ventricular performance on mid-term follow-up.

Evidence of impaired longitudinal strain in pre-Fontan palliation in functional single left ventricle.

BACKGROUND: We evaluated two-dimensional speckle-tracking echocardiography longitudinal strain (L2DSE) in functionally single left ventricles (LV). METHODS: We retrospectively analyzed 21 patients with functionally single LV. We divided patients into two groups according to pre-Fontan cardiac catheterization data: group 1, adequate data for Fontan procedure and group 2, inadequate data. RESULTS: LV strain correlated with predicted pressure in the Fontan system (r = 0.64; P = 0.003), pressure in the Glenn system (r = 0.57; P = 0.010), and transpulmonary gradient (r = 0.59; P = 0.008), but not with left atrial pressure (r = 0.292; P = 0.226) or ejection fraction (r = 0.254; P = 0.294). In multiple regression analysis, four-chamber LV strain was correlated with predicted pressure in the Fontan (ß = 0.642: P = 0.003), whereas no association was found with LV ejection fraction (ß = 0.254; P = 0.294), or time from Glenn palliation (ß = 0.082; P = 0.893). When dividing the population into two groups according to catheterization data, significantly lower four-chamber longitudinal 2DSE (-25.8 ±â€Š3.2 vs.-19.5 ±â€Š5.1; P = 0.004) was found to be not suitable for the Fontan procedure, as compared with those who underwent successful Fontan completion. CONCLUSION: Regardless of ejection fraction, four-chamber L2DSE is associated with high predicted pressure in the Fontan system. Patients with hemodynamic data unsuitable for Fontan operation have significantly lower mean longitudinal strain parameters. 2DSE may represent a valuable tool in assessing patients with single LV physiology and might provide useful pre-Fontan information.

Outcome for Conservative Surgery for the Correction of Severe Mitral Valve Regurgitation in Children: A Single-Center Experience.

Evolving reconstructive techniques have progressively become the preferred approach for treatment of pediatric mitral valve regurgitation. We present our experience in a cohort of patients undergoing surgical correction for severe mitral regurgitation. Fifty-five patients (age 1 month-18 years; median 5 years) were included in the present analysis. Different surgical techniques were used (posterior leaflet augmentation in 25, isolated cleft closure in 12, Alfieri-type procedure in 10, annuloplasty in 5, with artificial chordae in 2, and quadrangular resection with chordal transposition in 1). Follow-up time ranged from 1 to 192 months (median 38[IQR 12-54] months). Operative and follow-up mortality was 0%. Reintervention in the whole population occurred in 31% of patients. However, when first surgery was performed under 2 years of age (no = 17), reintervention reached nearly 50%. The degree of residual mitral regurgitation at follow-up remained stable after surgery, while a significant increase in mean transmitral gradient was observed over time (paired t test = 0.03). In multivariable Cox-regression analysis, post-surgical transmitral gradient was the only independent predictor for reintervention (p = 0.017; HR 2.4; 95%CI 1.2-5.1), after correcting for differences in age at surgery, type of reintervention, mitral annulus dimension, and BSA at the first surgery. ROC curve demonstrated that a post-surgical transmitral mean gradient value > 5 mmHg, was predictive for reintervention (AUC = 0.89; Youden index = 0.44). Our study suggests that the use of conservative technique strategy achieves satisfactory functional results in infants and children with severe MR, although the rate of reoperation in younger patients remains substantial. Post-operative moderate mitral stenosis was the strongest predictor for reoperation.

Italian survey on cardiac surgery for adults with congenital heart disease: which surgery, where and by whom?

OBJECTIVES: The population of ageing adults with congenital heart disease (ACHD) is increasing; surgery in these patients presents major difficulties in management. A great debate has developed about whether these patients should be cared for at an adult or paediatric hospital and by an acquired or congenital cardiac surgeon. We analysed data of the surgical treatment of ACHD from the Italian cardiac surgery centres in 2016, focusing on the type of surgery performed, where these patients were operated on and by whom. METHODS: Ninety-two Italian cardiac surgery centres were contacted and 70 centres participated in this study. We collected data on the types of cardiac operations performed in congenital heart defect patients older than 18 years. In 2016, a total of 913 patients with ACHD were operated on: 440 by congenital cardiac surgeons (group I) in centres with paediatric and adult cardiac surgery units, and 473 by adult cardiac surgeons (group II) in centres with exclusively adult cardiac surgery units. RESULTS: Pathologies of the right ventricular outflow tract were the most frequent diseases treated in group I and pathologies of the left ventricular outflow tract in group II. Group I included more complex and heterogeneous cases than group II. Surgery for ACHD represented 12% of the activity of congenital cardiac surgeons and only 1% of the activity of adult cardiac surgeons. CONCLUSIONS: In Italy, ACHD patients are operated on both by congenital and adult cardiac surgeons. Congenital cardiac surgeons working in centres with both paediatric and adult cardiac surgery are more involved with ACHD patients and with more complex cases.

Impact of Heparin- or Nonheparin-Coated Circuits on Platelet Function in Pediatric Cardiac Surgery.

BACKGROUND: Extracorporeal circuit coating has been shown to improve coagulation derangements during pediatric cardiopulmonary bypass (CPB). This study compared platelet function and hemostasis activation in pediatric cardiac surgery conducted with nonheparin coating (Balance; Medtronic, Minneapolis, MN) versus heparin-based coating (Carmeda; Medtronic) circuits. METHODS: A prospective, randomized, double-center trial was conducted in children older than 1 month undergoing congenital heart disease treatment. Blood samples were collected at baseline (T0), 15 minutes after the start of CPB (T1), and 15 minutes (T2) and 1 hour after the conclusion of CPB (T3). The primary end point of the study was to detect potential differences in ß-thromboglobulin levels between the two groups at T2. Other coagulation and platelet function indicators were analyzed as secondary end points. RESULTS: The concentration of ß-thromboglobulin increased significantly at T2 in both groups. However, there was no significant difference between the groups across all time points. There was no difference in the secondary end points between the groups. CONCLUSIONS: The two circuits showed similar biological effects on platelet function and coagulation. This observation may be useful in optimizing the conduct of CPB and in rationalizing its cost for the treatment of congenital heart disease.

Lung Transplantation for Late-Onset Pulmonary Hypertension in a Patient with Congenital Diaphragmatic Hernia.

Lung hypoplasia and pulmonary hypertension (PH) in association with congenital diaphragmatic hernia (CDH) may cause fatal respiratory failure. Lung transplantation (Ltx) may represent an option for CDH-related end-stage pulmonary failure. The aim of this study is to report a patient with CDH who underwent Ltx or combined heart-lung transplantation (H-Ltx). Our patient was born at 33 weeks of gestation, with a prenatally diagnosed isolated left CDH. Twenty-four hours after birth, she underwent surgical repair of a type D defect (according to the CDH Study Group staging system). Postoperative course was unexpectedly uneventful, and she was discharged home at 58 days of life. Echocardiography before discharge was unremarkable. Periodic follow-up revealed gastroesophageal reflux (GER) and initial scoliosis. At the age of 10, she was readmitted for severe PH. Lung function progressively deteriorated, and at the age of 14, she underwent H-Ltx due to end-stage respiratory failure. After discharge, she developed recurrent respiratory tract infections, severe malnutrition, and drug-induced diabetes. Scoliosis and GER progressed, requiring posterior vertebral arthrodesis and antireflux surgery, respectively. Bronchiolitis obliterans further impaired her respiratory function, and though she had a second Ltx, she died at the age of 18, 4 and 1.5 years after the first and the second Ltx, respectively. Late-onset PH is an ominous complication of CDH. From our patient and the six further cases collected from the literature, Ltx may be considered as a last-resource treatment in CDH patients with irreversible and fatal respiratory failure, although its prognosis seems unfair.

Midterm Echocardiographic Assessment of Right Ventricular Function After Midline Unifocalization.

BACKGROUND: Patients with an open ventricular septal defect (VSD) after repair of pulmonary atresia (PA), VSD, and major aortopulmonary collaterals (MAPCAs) are the most vulnerable subgroup. We analyzed the impact of concomitant versus delayed VSD closure on survival and intermediate-term right ventricular (RV) function. METHODS: Between October 1996 and February 2017, 96 patients underwent a pulmonary flow study-aided repair of PA/VSD/MAPCAs. For patients who underwent either concomitant or delayed intracardiac repair, echocardiographic RV systolic function was retrospectively calculated to assess (1) RV fractional area change (RVFAC) and (2) two-dimensional RV longitudinal strain (RVLS) of the free wall of the right ventricle. QLAB cardiac analysis software version 10.3 (Philips Medical Systems, Andover, MA) was used for analysis. RESULTS: A total of 64 patients underwent concomitant VSD closure at the time of unifocalization, and 16 patients underwent delayed VSD closure at a median of 2.3 years (range: 3 days to 7.4 years). At a median follow-up of 8.1 years (range: 0.1 to 19.5 years) for the concomitant repair group versus 7.4 years (range: 0.01 to 15.3 years) for the delayed repair group, no differences in RVFAC and RVLS were observed (RVFAC: 41.0% ± 6.2% versus 41.2% ± 7.6%, p = 0.91; RVLS: -18.7 ± 4.3 versus -18.9 ± 4.0, p = 0.87). CONCLUSIONS: Patients (83%) with PA/VSD/MAPCAs underwent complete repair at intermediate-term follow-up with preserved RV function. Delayed VSD closure was accomplished in 50% of the patients initially deemed unsuitable for repair. Delayed VSD closure did not affect survival and did not portend impaired RV systolic function.

Long-term survival and phenotypic spectrum in heterotaxy syndrome: A 25-year follow-up experience.

BACKGROUND: Heterotaxy syndrome (HS) is a group of congenital disorders characterized by abnormal arrangement of thoraco-abdominal organs across the left-right axis of the body, classified as right (RAI) and left atrial isomerism (LAI)·We investigated the long-term survival and phenotypic spectrum in our HS cohort. Results are compared to literature data. METHODS: This is a single centre, observational, both retro and prospective study. Cardiac features, surgical management and abdominal ultrasound (US) of all HS patients were reviewed or investigated if missing. We evaluated all anatomical data and their clinical impact on survival, arrhythmias, infections, and heart transplant (HT). RESULTS: 136 patients were classified as RAI (81) and LAI (55). Long-term survival and freedom from HT reached 69.8% and 87.8% at 40 years in RAI and LAI, respectively. Multivariate analysis showed that LAI is an independent predictor for pacemaker implantation (p = 0.019). Splenic status varied in both groups: in RAI, abdominal US showed asplenia, polysplenia and normal spleen in 48%, 4% and 32% of patients, respectively, whereas in LAI polysplenia, asplenia and normal spleen occurred in 64%, 4% and 16% of cases, respectively. CONCLUSIONS: Mortality was significantly lower (9%) compared to literature (50%). Although patients with RAI experienced a higher mortality, no independent predictors were found. We demonstrated that the obsolete cardiac definition of "asplenia" and "polysplenia" instead of RAI and LAI is misleading, because of the high variability of the splenic phenotype among patients of both groups.

Bradyarrhythmias in Repaired Atrioventricular Septal Defects: Single-Center Experience Based on 34 Years of Follow-Up of 522 Patients.

Atrioventricular Septal Defect (AVSD) is a rare congenital heart defect (CHD) often associated with genetic syndromes, most commonly Down syndrome (DS). Over the last four decades, surgical repair has increased survival and improved quality of life in these patients. The prevalence of bradyarrhythmias namely, atrioventricular block (AVB) and sinus node dysfunction (SND) in AVSD is partially known. 522 cases with both partial and complete AVSD (38.7% with DS), undergoing intracardiac repair from 1982 to 2016 at our institution, were reviewed from our system database. 38 (7.3%) patients received permanent PM implantation for AVB (early or late) or SND. On one hand, AVB requiring PM was found in 26 (4.98%). This was further subdivided into early-onset 14 (2.6%) and late-onset AVB 12 (2.2%) (median 4 [IQR 1-7] years). On the other hand, 12 (2.3%) experienced late SND requiring PM (median 11 [IQR 3.5-15.2] years). Early and late AVB were independent from the type of AVSD (partial or complete), whereas the late SND was remarkably observed in complete AVSD compared to partial AVSD (p = 0.017). We classified the cohort into two main categories: DS (202, 38.7%) and non-DS (320, 61.3%). At Kaplan-Meier survival analysis, DS was significantly associated with late-onset bradyarrhythmias (p = 0.024). At Cox regression analysis, we identified DS as an independent predictor of PM implantation (HR 2.17). In conclusion, about 7% of repaired AVSD patients need PM implantation during follow-up. There are no differences in early and late AVB occurrence according to the type of AVSD. There is a higher incidence of late SND in repaired complete AVSD, with a later timing onset in patients with associated DS. Moreover, DS seems to be an independent predictor of PM implantation.

Congenital heart diseases and cardiovascular abnormalities in 22q11.2 deletion syndrome: From well-established knowledge to new frontiers.

Congenital heart diseases (CHDs) and cardiovascular abnormalities are one of the pillars of clinical diagnosis of 22q11.2 deletion syndrome (22q11.2DS) and still represent the main cause of mortality in the affected children. In the past 30 years, much progress has been made in describing the anatomical patterns of CHD, in improving their diagnosis, medical treatment, and surgical procedures for these conditions, as well as in understanding the underlying genetic and developmental mechanisms. However, further studies are still needed to better determine the true prevalence of CHDs in 22q11.2DS, including data from prenatal studies and on the adult population, to further clarify the genetic mechanisms behind the high variability of phenotypic expression of 22q11.2DS, and to fully understand the mechanism responsible for the increased postoperative morbidity and for the premature death of these patients. Moreover, the increased life expectancy of persons with 22q11.2DS allowed the expansion of the adult population that poses new challenges for clinicians such as acquired cardiovascular problems and complexity related to multisystemic comorbidity. In this review, we provide a comprehensive review of the existing literature about 22q11.2DS in order to summarize the knowledge gained in the past years of clinical experience and research, as well as to identify the remaining gaps in comprehension of this syndrome and the possible future research directions.