22q11.2 Deletion Syndrome: Impact of Genetics in the Treatment of Conotruncal Heart Defects.

Congenital heart diseases represent one of the hallmarks of 22q11.2 deletion syndrome. In particular, conotruncal heart defects are the most frequent cardiac malformations and are often associated with other specific additional cardiovascular anomalies. These findings, together with extracardiac manifestations, may affect perioperative management and influence clinical and surgical outcome. Over the past decades, advances in genetic and clinical diagnosis and surgical treatment have led to increased survival of these patients and to progressive improvements in postoperative outcome. Several studies have investigated long-term follow-up and results of cardiac surgery in this syndrome. The aim of our review is to examine the current literature data regarding cardiac outcome and surgical prognosis of patients with 22q11.2 deletion syndrome. We thoroughly evaluate the most frequent conotruncal heart defects associated with this syndrome, such as tetralogy of Fallot, pulmonary atresia with major aortopulmonary collateral arteries, aortic arch interruption, and truncus arteriosus, highlighting the impact of genetic aspects, comorbidities, and anatomical features on cardiac surgical treatment.

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.

Predictors of survival in paediatric mitral valve surgery: the impact of age at operation at late follow-up.

OBJECTIVES: The aim of this study was to elucidate predictors of death and reintervention after mitral valve (MV) surgery in children. METHODS: A single-centre retrospective study was performed enrolling 142 patients younger than 18 years who underwent primary index surgical mitral repair or replacement at Bambino Gesù Children's Hospital in Rome from July 1982 to April 2020. Patients with complete, transitional or partial atrioventricular septal defect and patients with single ventricle physiology were excluded. Patients were stratified according to the age group: group 1 (<1 year old), group 2 (1-5 years old) and group 3 (>5 years old). The composite primary outcome was freedom from death or transplant. The secondary outcome was freedom from redo MV surgery. RESULTS: Transplant-free survival was 89% at 5 years and 88% at 10 years. Stratified by age, group 1 had poorer outcome in comparison with other groups (log-rank test P = 0.105). Both univariate and multivariate analyses showed that age <1 year was a significant risk factor for death or transplant (P = 0.044). Age <1 year was associated with increased risk of reoperation (aHR = 3.38, P = 0.009), while the presence of genetic syndrome (aHR = 0.22) and preoperative EF% (aHR = 0.97) were protective factors for reoperation. CONCLUSIONS: The overall survival and freedom from reoperation in children undergoing MV surgery still need improvements. Younger age was a significant risk factor for death and reintervention both after repair and replacement of the MV. In particular, infants and neonates have a three-fold risk for death compared to children.

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.

Ascending aortic extension to increase aortopulmonary space after comprehensive stage II palliation.

Aortic reconstruction at the time of the comprehensive stage II (CSII) procedure can be complicated by compression within the aortopulmonary space resulting in airway or pulmonary artery narrowing. We describe our experience with 2 patients with hypoplastic left heart syndrome and pulmonary artery stenosis after the CSII procedure. Both patients underwent an aortic extension with a Hemashield interposition graft to open up the aortopulmonary space. The patients were discharged from the hospital. In all cases the aortopulmonary space was enlarged, and the pulmonary arteries and airway were free from compression. Aortic extension is an option to be considered in children with pulmonary artery compression who previously had a CSII procedure.

Use of Transcarotid IMPELLA 2.5 Axial-Flow Pump Device for Left Ventricle Unloading During VA-ECMO Support in Pediatric Acute Heart Failure.

An alternative strategy for left ventricular (LV) venting during short-term mechanical circulatory support is use of Impella axial-flow pump. We present our transcarotid Impella 2.5 implantation technique using a polytetrafluoroethylene graft, in two children with acute heart failure treated primarily with venoarterial ECMO. The venoarterial extracorporeal membrane oxygenator and Impella support were maintained for 5 and 17 days, respectively. Transcarotid Impella implantation might be an alternative and feasible option in pediatrics patients affected by severe LV failure, as a bridge to decision or bridge to candidacy. Potentially, the Impella 2.5 device provides less invasive support for children with heart failure.

Use of carotid artery cannulation during redo sternotomy in congenital cardiac surgery: a single-centre experience.

OBJECTIVES: Management of resternotomy is often a difficult challenge in patients with congenital diseases who have undergone multiple sternotomies. Our goal was to report our single-centre experience with carotid cannulation using a graft interposed during redo sternotomy in complex cardiac reintervention procedures. METHODS: We performed a retrospective review of all patients who had undergone complex redo sternotomies between January 2019 and May 2020 utilizing a cervical cannulation technique with a Gore-Tex graft interposed on the carotid artery. We classified our population study on the basis of the primary diagnosis and the type of surgery. The primary outcomes of our analysis were the evaluation of the safety of the procedure in terms of survival and freedom from neurological events. RESULTS: We analysed 22 patients who had undergone previous complex operations. The median age and weight at the time of reintervention were 130.35 (range 0.46-435) months and 31.5 (range 2.2-85) kg, respectively. Composite graft carotid cannulation provided adequate arterial flow in all patients with a median arterial flow of 3.5 l/min/m2 (range 0.6-6). One major cardiac injury occurred during sternotomy when emergency cardiopulmonary bypass (CPB) was initiated. Moreover, during their hospital stays, all patients had an uneventful recovery without neurological or vascular complications and no cervical wound infections. CONCLUSIONS: Carotid cannulation using interposition of a side graft on the common carotid artery for arterial inflow is a reliable and safe method for initiation of CPB in complex redo surgeries in patients with congenital disease. Complications directly associated with this type of cannulation are uncommon and allow surgical re-entry with overall low risks.

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.

Long-term veno-arterial extracorporeal membrane oxygenation as a bridge to heart-lung transplant.

En bloc heart-lung transplantation still represents definitive therapy for end-stage cardiopulmonary failure. However, patients may critically decompensate while awaiting suitable donor organs and necessitate veno-arterial extracorporeal membrane oxygenation. In this article, we describe the combined use of central cannulation with the Berlin Heart EXCOR ventricular assist device cannulae and the CentriMag centrifugal pump as an extended bridge to heart-lung transplantation in three pediatric patients.

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.

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.

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.

Bronchial Mismatch as a Predictor of Respiratory Failure After Congenital Tracheal Stenosis Repair.

BACKGROUND: The purpose of this study was to identify predictors of postoperative respiratory failure after surgical tracheoplasty for congenital tracheal stenosis. METHODS: Between February 2011 and April 2017, 16 infants underwent congenital tracheal stenosis repair. Preoperative computed tomography evaluation of the trachea and mainstem bronchi was performed. The primary outcome was midterm freedom from postoperative respiratory failure defined as persistent need for mechanical ventilation or surgical tracheobronchial reoperation. Bronchial mismatch, defined as [1 - (smaller bronchus diameter / larger bronchus diameter)] × 100, was analyzed in relation to the primary outcome. RESULTS: Median age was 106 days (range, 1 to 406) and median weight was 5.3 kg (range, 2.6 to 8 kg). Four patients were neonates (25%) and 6 had genetic abnormalities (37.5%). There were no early nor late deaths. Median ventilation time was 5.5 days (range, 3 to 45). Mean follow-up time was 2.2 years (range, 0.1 to 4.5). Four patients with bronchial mismatch greater than 20% had postoperative respiratory failure (p = 0.002). Two of them underwent tracheostomy and were discharged with ventilation home care support. One underwent successful reoperation consisting of bilateral bronchial plasty with autologous cartilage rib grafts, and the other underwent successful right bronchial and tracheal reconstruction. One patient with bilateral bronchial hypoplasia underwent slide tracheoplasty associated with preemptive bilateral bronchial plasty and made a full recovery. CONCLUSIONS: Surgical treatment of congenital tracheal stenosis in neonates and infants portends a good outcome. Bronchial mismatch greater than 20% can identify a subset of patients at increased risk for surgical reintervention and chronic respiratory failure. Slide tracheoplasty with preemptive bronchial reconstruction may prevent postoperative respiratory failure.

Long-Term Outcomes After Extracardiac Fontan Takedown to an Intermediate Palliative Circulation.

BACKGROUND: Acute failure of the Fontan circulation is rare but remains associated with high morbidity and mortality rates. Little is known about the long-term outcome of patients who underwent Fontan takedown to an intermediate palliative circulation and their potential candidacy for redo Fontan completion. METHODS: Patients followed up at a single institution who underwent takedown of a Fontan circulation to an intermediate palliative circulation within 2 months of extracardiac Fontan completion were reviewed. RESULTS: Between October 1990 and December 2015, 18 patients underwent Fontan takedown to a superior cavopulmonary connection (with or without an additional shunt) at a median age of 3.3 years (range, 1.8 to 8.0) and median weight of 13.8 kg (range, 8.0 to 27.0 kg). Takedown was required during the Fontan procedure itself in 2 patients, and within the first 2 postoperative months in 16 patients (median time to takedown, 3 days). Seventeen patients survived the post-takedown period and 3 ultimately underwent successful redo Fontan. Four patients required heart transplantation, with 2 deaths. In patients with extended intermediate palliation, median arterial oxygen saturation was 84% (range, 76% to 92%) at a median follow-up of 6.3 years (range, 0.7 to 25.9). CONCLUSIONS: Takedown to a superior cavopulmonary connection is an effective treatment option and, in some patients, acts as a bridge to subsequent redo Fontan completion or heart transplantation. An extended intermediate palliative circulation is tolerated for several years with reasonable oxygen saturation levels at rest. In our experience, an early takedown strategy to a superior cavopulmonary connection is the treatment of choice for acute Fontan failure.