Long-term outcomes of truncus arteriosus repair: A modulated renewal competing risks analysis.

OBJECTIVE: In this study, we sought to identify independent risk factors for mortality and reintervention after early surgical correction of truncus arteriosus using a novel statistical method. METHODS: Patients undergoing neonatal/infant truncus arteriosus repair between January 1984 and December 2018 were reviewed retrospectively. An innovative statistical strategy was applied integrating competing risks analysis with modulated renewal for time-to-event modeling. RESULTS: A total of 204 patients were included in the study. Mortality occurred in 32 patients (15%). Smaller right ventricle to pulmonary artery conduit size and truncal valve insufficiency at birth were significantly associated with overall mortality (right ventricle to pulmonary artery conduit size: hazard ratio, 1.34; 95% confidence interval, 1.08-1.66, P = .008; truncal valve insufficiency: hazard ratio, 2.5; 95% confidence interval, 1.13-5.53, P = .024). truncal valve insufficiency at birth, truncal valve intervention at index repair, and number of cusps (4 vs 3) were associated with truncal valve reoperations (truncal valve insufficiency: hazard ratio, 2.38; 95%, confidence interval, 1.13-5.01, P = .02; cusp number: hazard ratio, 6.62; 95% confidence interval, 2.54-17.3, P < .001). Right ventricle to pulmonary artery conduit size 11 mm or less was associated with a higher risk of early catheter-based reintervention (hazard ratio, 1.54; 95% confidence interval, 1.04-2.28, P = .03) and reoperation (hazard ratio, 1.96; 95% confidence interval, 1.33-2.89, P = .001) on the right ventricle to pulmonary artery conduit. CONCLUSIONS: Smaller right ventricle to pulmonary artery conduit size and truncal valve insufficiency at birth were associated with overall mortality after truncus arteriosus repair. Quadricuspid truncal valve, the presence of truncal valve insufficiency at the time of diagnosis, and truncal valve intervention at index repair were associated with an increased risk of reoperation. The size of the right ventricle to pulmonary artery conduit at index surgery is the single most important factor for early reoperation and catheter-based reintervention on the conduit.

Outcomes after common arterial trunk repair: Impact of the surgical technique.

OBJECTIVES: We compared the risk of mortality and reintervention after common arterial trunk (CAT) repair for different surgical techniques, in particular the reconstruction of the right ventricle outflow tract with left atrial appendage (LAA) without a monocusp. METHODS: The study population comprised 125 patients with repaired CAT who were followed-up at our institution between 2000 and 2018. Statistical analysis included Cox proportional hazard models. RESULTS: Median follow-up was 10.6 years. The 10-year survival rate was 88.2% (95% confidence interval [CI], 80.6-92.4) with the poorest outcome for CAT type IV (64.3%; 95% CI, 36.8-82.3; P < .01). In multivariable analysis, coronary anomalies (hazard ratio [HR], 11.63 [3.84-35.29], P < .001) and CAT with interrupted aortic arch (HR, 6.50 [2.10-20.16], P = .001) were substantial and independent risk factors for mortality. Initial repair with LAA was not associated with an increased risk of mortality (HR, 0.37 [0.11-1.24], P = .11). The median age at reintervention was 3.6 years [7.3 days-13.1 years]. At 10 years, freedom from reintervention was greater in the group with LAA repair compared with the valved conduit group, 73.3% (95% CI, 41.3-89.4) versus 17.2% (95% CI, 9.2-27.4) (P < .001), respectively. Using a valved conduit for repair (HR, 4.79 [2.45-9.39], P < .001), truncal valve insufficiency (HR, 2.92 [1.62-5.26], P < .001) and DiGeorge syndrome (HR, 2.01 [1.15-3.51], P = .01) were independent and clinically important risk factors for reintervention. CONCLUSIONS: For the repair of CAT, the LAA technique for right ventricle outflow tract reconstruction was associated with comparable survival and greater freedom from reintervention than the use of a valved conduit.

Effect of Stiffened and Dilated Ascending Aorta on Aerobic Exercise Capacity in Repaired Patients With Complex Congenital Heart Disease.

Several studies have reported aortic dilation and increased stiffness of the ascending aorta in patients after repair of congenital heart disease (CHD), which may be a predominant cardiovascular risk. However, the clinical significance has not been described in detail. In this retrospective study, 175 repaired patients with complex CHD achieving biventricular circulation and age-matched 39 control subjects were reviewed (median age: 14.9 and 15.7 years, respectively). We measured the diameters of the ascending aorta and descending aorta from catheterization angiograms to yield Z-scores and stiffness indexes (ß) using diameter fluctuations corresponding to pulsatile pressures. Clinical profile, peak oxygen uptake during the cardiopulmonary exercise test, and incidence of unscheduled hospitalization during follow-up was also reviewed. Compared with controls, patients with complex CHD, except for those with aortic coarctation, exhibited significant dilation and increased stiffness of the aortic root and ascending aorta, but not of the descending aorta. In this CHD population (n = 147, including 112 conotruncal anomalies), exercise capacities correlated independently with the diameter Z-score and stiffness index of the ascending aorta along with the history of repetitive thoracotomies, reduced forced vital capacity, and right ventricular hypertension. During a follow-up period (median 15.6 years), either dilation (Z-score >3.5) or increased stiffness (ß >6.0) of the ascending aorta stratified morbidity, but no synergistic impact was detected. In conclusion, in repaired patients with complex CHD, a stiffened and dilated ascending aorta was frequently found, exerting significant adverse impacts on diminished exercise capacity and morbidity.

Hemitruncus Arteriosus in a 10-Day-Old Neonate with Patent Ductus Arteriosus and Thrombocytopenia.

Hemitruncus arteriosus refers to an uncommon congenital cardiovascular abnormality. It usually presents in infancy and leads to the development of pulmonary hypertension, heart failure, and in severe cases maybe death. Herein, we reported hemitruncus arteriosus in a 10-day-old neonate with respiratory distress, patent ductus arteriosus, and thrombocytopenia.

Is two-staged repair for truncus arteriosus type A3 unpractical?

BACKGROUND: A complex and rare form of persistent truncus arteriosus needs careful attention when choosing the optimal strategy for repair. AIM OF THE STUDY: We herein describe our surgical strategy of a small infant having this malformation concomitantly with right aortic arch, unusual pulmonary artery branching and a left superior vena cava. METHODS: The patient underwent initially bilateral pulmonary arterial banding followed by the Rastelli type definitive repair. The pulmonary arteries were unified in front of the left superior vena cava, and the right ventricular outflow tract was readily reconstructed. RESULTS: The patient is doing well with an excellent hemodynamic status. CONCLUSIONS: We considered the two-stage approach was sensible in this particular patient.

Truncus arteriosus with retrograde aortic flow: a unique case.

Truncus arteriosus is a rare cyanotic congenital heart defect that involves septation failure of the heart's main arterial outflow tract. Varying morphologies of the truncal valve and aorta have been reported; however, the ascending aorta is typically supplied via anterograde blood flow through the truncal valve. We present the first reported case of neonatal truncus arteriosus with the ascending aorta being supplied entirely by retrograde flow.

Utilization of inhaled nitric oxide after surgical repair of truncus arteriosus: A multicenter analysis.

BACKGROUND: Elevated pulmonary vascular resistance (PVR) is common following repair of truncus arteriosus. Inhaled nitric oxide (iNO) is an effective yet costly therapy that is frequently implemented postoperatively to manage elevated PVR. OBJECTIVES: We aimed to describe practice patterns of iNO use in a multicenter cohort of patients who underwent repair of truncus arteriosus, a lesion in which recovery is often complicated by elevated PVR. We also sought to identify patient and center factors that were more commonly associated with the use of iNO in the postoperative period. DESIGN: Retrospective cohort study. SETTING: 15 tertiary care pediatric referral centers. PATIENTS: All infants who underwent definitive repair of truncus arteriosus without aortic arch obstruction between 2009 and 2016. INTERVENTIONS: Descriptive statistics were used to demonstrate practice patterns of iNO use. Bivariate comparisons of characteristics of patients who did and did not receive iNO were performed, followed by multivariable mixed logistic regression analysis using backward elimination to identify independent predictors of iNO use. MAIN RESULTS: We reviewed 216 patients who met inclusion criteria, of which 102 (46%) received iNO in the postoperative period: 69 (68%) had iNO started in the operating room and 33 (32%) had iNO initiated in the ICU. Median duration of iNO use was 4 days (range: 1-21 days). In multivariable mixed logistic regression analysis, use of deep hypothermic circulatory arrest (odds ratio: 3.2; 95% confidence interval: 1.2, 8.4) and center (analyzed as a random effect, p = .02) were independently associated with iNO use. CONCLUSIONS: In this contemporary multicenter study, nearly half of patients who underwent repair of truncus arteriosus received iNO postoperatively. Use of iNO was more dependent on individual center practice rather than patient characteristics. The study suggests a need for collaborative quality initiatives to determine optimal criteria for utilization of this important but expensive therapy.

Characteristics of Cardiovascular Magnetic Resonance Imaging and Outcomes in Adults With Repaired Truncus Arteriosus.

The cardiovascular magnetic resonance imaging (CMR) features of adults with repaired truncus arteriosus (rTA) are largely undefined. We sought to explore CMR characteristics in rTA and to identify associations between imaging findings and cardiovascular outcomes. Adults with rTA and CMR were identified and anatomic subtypes (1-4) were assigned (Collett and Edwards classification). CMR characteristics, clinical data at last follow-up and adverse cardiovascular outcome were recorded. Twenty-seven adults (19% male) were studied (median age at cardiovascular magnetic resonance 26 years [interquartile range 18 to 40]) over 5.2-year duration [interquartile range 2.5 to 7.5]. With the exception of mildly increased RV mass (30 ± 12 g/m2), cardiac chamber measurements were within the normal range. In CMR measurements, only pulmonary artery peak velocity differed in subtypes (highest in subtype 3, 318 ± 26 cm/s, p = 0.029). Number of cardiovascular interventions in adulthood was moderately correlated with left ventricular end-diastolic volume (r = 0.463, p = 0.015), left ventricular ejection fraction (r = 0.425, p = 0.027) and neoaortic root size (r = 0.398, p = 0.039). Cardiovascular events (nonmutually exclusive) in 5 of 27 patients (19%) included death (n = 1), heart failure (n = 1), ventricular tachycardia (n = 1), and atrial tachycardia (n = 3). Increased cardiovascular risk was associated with decreased right ventricular ejection fraction (odds ratio 1.153, confidence interval 1.003 to 1.326, p = 0.046) and smaller ascending aorta diameter (odds ratio 1.758, confidence interval 1.037 to 2.976, p = 0.036). In conclusion, decreased right ventricular ejection fraction and smaller ascending aorta on cardiovascular magnetic resonance were associated with adverse events in rTA.

GATA6 mutations: Characterization of two novel patients and a comprehensive overview of the GATA6 genotypic and phenotypic spectrum.

The first human mutations in GATA6 were described in a cohort of patients with persistent truncus arteriosus, and the phenotypic spectrum has expanded since then. This study underscores the broad phenotypic spectrum by presenting two patients with de novo GATA6 mutations, both exhibiting complex cardiac defects, pancreatic, and other abnormalities. Furthermore, we provided a detailed overview of all published human genetic variation in/near GATA6 published to date and the associated phenotypes (n = 78). We conclude that the most common phenotypes associated with a mutation in GATA6 were structural cardiac and pancreatic abnormalities, with a penetrance of 87 and 60%, respectively. Other common malformations were gallbladder agenesis, congenital diaphragmatic hernia, and neurocognitive abnormalities, mostly developmental delay. Fifty-eight percent of the mutations were de novo, and these patients more often had an anomaly of intracardiac connections, an anomaly of the great arteries, and hypothyroidism, compared with those with inherited mutations. Functional studies mostly support loss-of-function as the pathophysiological mechanism. In conclusion, GATA6 mutations give a wide range of phenotypic defects, most frequently malformations of the heart and pancreas. This highlights the importance of detailed clinical evaluation of identified carriers to evaluate their full phenotypic spectrum.

Dysregulation of TBX1 dosage in the anterior heart field results in congenital heart disease resembling the 22q11.2 duplication syndrome.

Non-allelic homologous recombination events on chromosome 22q11.2 during meiosis can result in either the deletion (22q11.2DS) or duplication (22q11.2DupS) syndrome. Although the spectrum and frequency of congenital heart disease (CHD) are known for 22q11.2DS, there is less known for 22q11.2DupS. We now evaluated cardiac phenotypes in 235 subjects with 22q11.2DupS including 102 subjects we collected and 133 subjects that were previously reported as a confirmation and found 25% have CHD, mostly affecting the cardiac outflow tract (OFT). Previous studies have shown that global loss or gain of function (LOF; GOF) of mouse Tbx1, encoding a T-box transcription factor mapping to the region of synteny to 22q11.2, results in similar OFT defects. To further evaluate Tbx1 function in the progenitor cells forming the cardiac OFT, termed the anterior heart field, Tbx1 was overexpressed using the Mef2c-AHF-Cre driver (Tbx1 GOF). Here we found that all resulting conditional GOF embryos had a persistent truncus arteriosus (PTA), similar to what was previously reported for conditional Tbx1 LOF mutant embryos. To understand the basis for the PTA in the conditional GOF embryos, we found that proliferation in the Mef2c-AHF-Cre lineage cells before migrating to the heart, was reduced and critical genes were oppositely changed in this tissue in Tbx1 GOF embryos versus conditional LOF embryos. These results suggest that a major function of TBX1 in the AHF is to maintain the normal balance of expression of key cardiac developmental genes required to form the aorta and pulmonary trunk, which is disrupted in 22q11.2DS and 22q11.2DupS.

Modified Repair of Type I and II Truncus Arteriosus Limits Early Right Ventricular Outflow Tract Reoperation.

Repair of truncus arteriosus often requires early right ventricular outflow tract (RVOT) reoperation. Using a modified repair, the branch pulmonary arteries are left in situ, which may avoid earlier RVOT reoperation. We hypothesized that our modified repair for type I and II truncus arteriosus would extend the time to RVOT reoperation. Infants with truncus arteriosus were divided into 2 groups: (1) traditional technique where the branch pulmonary arteries are excised from the truncal root, or (2) modified repair where the branch pulmonary arteries are left in situ and septated from the truncal root. Regardless of the approach, a bioprosthetic conduit or homograft was used to establish right ventricular to pulmonary artery continuity. Follow-up pulmonary artery angiograms were used to assess for branch pulmonary artery stenosis. From 54 infants (modified repair: 33, traditional technique: 21), there were no significant differences in age at repair, gender, or type of truncus arteriosus. With 100% follow-up, use of the modified repair resulted in a lower rate of branch pulmonary artery stenosis, and greater freedom from surgical branch pulmonary arterioplasty. Five- and 10-year freedom from RVOT reoperation (5 years: modified-81.5% vs traditional-30.5%, P = 0.004; 10 years: modified-53.3% vs traditional-30.5%, P = 0.01) favored the modified repair. Cox regression analysis demonstrated that the modified repair was associated with an independently lower risk for RVOT reoperation (hazard ratio: 0.08, confidence interval: 0.01, 0.75, P = 0.02). Thus, maintaining the branch pulmonary artery architecture resulted in greater freedom from RVOT reoperation.

Late management of truncus arteriosus: 20 years of humanitarian experience.

OBJECTIVES: Early surgical management of common arterial trunk is well established and has good prognosis. Late diagnosis is less common. We reviewed late-diagnosed common arterial trunk management and prognosis for children in developing countries. We also discuss the need for prior catheterisation. Material and methods We reviewed all common arterial trunk patients managed by our humanitarian organization since 1996. RESULTS: A total of 41 children with common arterial trunk were managed at a mean age of 3 years old. The lack of adequate facilities in developing countries explains the late management. The decision to proceed with surgery was based on clinical and radiological symptoms of persistent shunt, particularly a high cutaneous saturation level, regardless of catheterization - not carried out systematically. Eight children had to be withdrawn and 33 (80.5%) received operation - mean saturation 91%. The postoperative course was marked by pulmonary arterial hypertension requiring specific treatment in 30% of cases. The operative mortality was 1/33. The 32 children returned home without treatment after a mean post operative stay of 49 days and were followed up (mean FU 3.4 years, none lost to follow-up). At last contact, 1 child died six months after surgery, 1 child had a massive truncal valve insufficiency, 5 had a significant stenosis of the RV-PA tube, and 2 have had further surgery for tube replacement. CONCLUSIONS: Late management and surgery of common arterial trunk is possible with good long-term results without prior hemodynamic examination up to an advanced childhood when signs of left-to-right shunt persist. A high saturation level (above 88%) seems to be a good operability criterion.

TBX20 loss-of-function mutation responsible for familial tetralogy of Fallot or sporadic persistent truncus arteriosus.

Congenital heart disease (CHD), the most common form of developmental abnormality in humans, remains a leading cause of morbidity and mortality in neonates. Genetic defects have been recognized as the predominant causes of CHD. Nevertheless, CHD is of substantial genetic heterogeneity and the genetic defects underlying CHD in most cases remain unclear. In the current study, the coding regions and splicing junction sites of the TBX20 gene, which encodes a T-box transcription factor key to cardiovascular morphogenesis, were sequenced in 175 unrelated patients with CHD, and a novel heterozygous TBX20 mutation, p.K274X, was identified in an index patient with tetralogy of Fallot (TOF). Genetic analysis of the proband's available family members showed that his father, elder brother and son had also TOF. In addition, his father and elder brother had also atrial septal defect, and his niece had persistent truncus arteriosus and ventricular septal defect. Analysis of the pedigree revealed that the mutation co-segregated with CHD transmitted in an autosomal dominant fashion, with complete penetrance. The nonsense mutation, which was absent in the 800 control chromosomes, was predicted to produce a truncated protein with only the amino terminus and partial T-box domain left. Functional analyses by using a dual-luciferase reporter assay system showed that the mutant TBX20 lost the ability to transactivate the target gene ANF. Furthermore, the mutation reduced the synergistic activation between TBX20 and NKX2.5 as well as GATA4, two other transcriptional factors previously associated with various CHD, encompassing TOF. This study firstly links TBX20 loss-of-function mutation to familial TOF or sporadic persistent truncus arteriosus, providing novel insight into the molecular pathogenesis of CHD.

Intra- and inter-reader reproducibility of blood flow measurements on the ascending aorta and pulmonary artery using cardiac magnetic resonance.

The aim of our study was to estimate the intra- and inter-reader reproducibility of blood flow measurements in the ascending aorta and main pulmonary artery using cardiac magnetic resonance (CMR) and a semi-automated segmentation method. The ethics committee approved this retrospective study. A total of 50 consecutive patients (35 males and 15 females; mean age±standard deviation 27±13 years) affected by congenital heart disease were reviewed. They underwent CMR for flow analysis of the ascending aorta and main pulmonary artery (1.5 T, through-plane phase-contrast sequences). Two independent readers (R1, trained radiology resident; R2, lower-trained technician student) obtained segmented images twice (>10-day interval), using a semi-automated method of segmentation. Peak velocity, forward and backward flows were obtained. Bland-Altman analysis was used and reproducibility was reported as complement to 100% of the ratio between the coefficient of repeatability and the mean. R1 intra-reader reproducibility for the aorta was 99% (peak velocity), 95% (forward flow) and 49% (backward flow); for the pulmonary artery, 99%, 91% and 90%, respectively. R2 intra-reader reproducibility was 92%, 91% and 38%; 98%, 86% and 87%, respectively. Inter-reader reproducibility for the aorta was 91%, 85% and 20%; for the pulmonary artery 96%, 75%, and 82%, respectively. Our results showed a good to excellent reproducibility of blood flow measurements of CMR together with a semiautomated method of segmentation, for all variables except the backward flow of the ascending aorta, with a limited impact of operator's training.

An unrepaired persistent truncus arteriosus in a 62-year-old adult.

: In this image focus, we describe the case an old woman with persistent unrepaired truncus arteriosus type III and Eisenmenger syndrome.

Dexmedetomidine attenuates hypoxemia during palliative reconstruction of the right ventricular outflow tract in pediatric patients.

The objective of this study was to investigate whether the α agonist dexmedetomidine has the ability to attenuate hypoxemia in pediatric patients undergoing palliative pulmonary artery reconstruction.From January 2009 to January 2013, a total of 25 pediatric patients with Tetralogy of Fallot, pulmonary atresia (ventricular septal defect), or persistent truncus arteriosus (I) were enrolled in our study. Due to hypoplastic pulmonary arteries, all patients received palliative pulmonary artery reconstruction. During the perioperative period, they were allocated to receive either dexmedetomidine (bolus dose of 0.3 µg/kg followed by an infusion of 0.2-0.3 µg/kg/h, n = 15) or control drug (n = 10) intravenously. Any desaturation was recorded. Heart rate, mean arterial pressure, pulse oximetry, and arterial blood gas parameters were measured during the perioperative period.There were no significant differences between the groups in hemodynamic variables. The arterial oxygen saturation and arterial blood gas parameters increased in the dexmedetomidine groups (P < 0.05).These findings suggest that the injection of dexmedetomidine can attenuate hypoxemia during palliative pulmonary artery reconstruction in pediatric patients.

Surgical treatment of common arterial trunk in patients beyond the first year of life.

BACKGROUND: Common arterial trunk (persistent truncus arteriosus) is a rare cardiac defect requiring surgical repair early in life because of the fast development of pulmonary vascular obstructive disease. We present our institutional experience with patients having common arterial trunk who are diagnosed after one year of age. PATIENTS AND METHODS: Between August 2010 and May 2013, a total of 1,436 patients were treated for congenital cardiac defects at our institution. Common arterial trunk was treated surgically in seven patients older than one year of age (three males, four females; age: 13 months to 5 years, mean: 2.8 ± 2.04 years). All patients underwent cardiac catheterization in order to determine operability. RESULTS: All patients had the aortic dominant type of common arterial trunk. The pulmonary vascular resistance and Qp/Qs ratio before and after oxygen inhalation were mean 9.04 + 4.2 (range: 3.8 and 10.7) wood units and 4.67 ± 2.3 (range: 3 and 6.5) wood units and 3.3 + 1.8 (range: 1.42 and 5.3) and 4.98 + 2.2 (range: 4 and 6.2), respectively. All patients underwent elective primary repair. The ventricular septal defect was closed in all patients, five with a nonvalved patch and two with a unidirectional check-valved patch. Early postoperatively, patients were sedated, hyperventilated, and received nitric oxide for a minimum of 24 hours. There was no early or late mortality. The mean length of hospital stay was 9.3 ± 5.7 days, and mean duration of follow-up was 214 ± 59 days. CONCLUSION: Complete repair of common arterial trunk in patients older than one year of age is feasible in appropriately selected cases. Preoperative cardiac catheterization to assess reactivity of the pulmonary vascular bed is important as are appropriate strategies for postoperative management. Together, these elements make it possible to achieve primary repair with excellent outcomes despite late presentation.