Transposition of the great arteries--outcomes and time interval of early neonatal repair

Ductal stenting for retraining the left ventricle in patients with transposition of great arteries with intact ventricular septum: a single-centre experience

INTRODUCTION

Ductal stenting in late presenters with transposition of great arteries with intact ventricular septum retrains the left ventricle before arterial switch operation. However, the experience is limited for its efficacy and safety. This study aims to highlight the efficacy and safety of ductal stenting for retraining the left ventricle.

METHODS

Eight children with transposition of great arteries-intact ventricular septum and regressed left ventricle underwent ductal stenting. Serial echocardiographic measurements of left ventricle shape, mass, volume, free wall thickness, and function were done, and arterial switch operation was performed once the left ventricle was adequately prepared. Post-operative outcome in terms of duration of mechanical ventilation, ICU stay, and improvement in left ventricle function were monitored.

RESULTS

The procedure was successful in all patients. Babies were divided into two groups on basis of age at ductal stenting (group 1 age less than 90 days and group 2 age more than 90 days) and were evaluated for the degree of left ventricle retraining as evidenced by echocardiographic parameters and post-operative variables. The left ventricle posterior wall thickness and mass index after ductal stenting increased significantly in both the groups. Postoperatively, one baby of group two expired after seven days due to severe left ventricle dysfunction. Rest babies had an uneventful post-operative ICU stay with no statistical difference in the duration of invasive mechanical ventilation or ICU stay. On six-month follow-up, all surviving babies were doing well with normal left ventricle function.

CONCLUSION

Ductal stenting is a good alternative measure as compared to surgical procedures for left ventricle retraining in transposition of great arteries with regressed left ventricle.

Arterial Switch for Transposition of the Great Arteries: Treatment Timing, Late Outcomes, and Risk Factors

Background

Reports of long-term mortality and reintervention after transposition of the great arteries with intact ventricular septum treatment, although favorable, are mostly limited to single-center studies. Even less is known about hospital resource utilization (days at hospital) and the impact of treatment choices and timing on outcomes.

Objectives

The purpose of this study was to describe survival, reintervention and hospital resource utilization after arterial switch operation (ASO) in a national dataset.

Methods

Follow-up and life status data for all patients undergoing ASO between 2000 and 2017 in England and Wales were collected and explored using multivariable regressions and matching.

Results

A total of 1,772 patients were identified, with median ASO age of 9.5 days (IQR: 6.5-14.5 days). Mortality and cardiac reintervention at 10 years after ASO were 3.2% (95% CI: 2.5%-4.2%) and 10.7% (95% CI: 9.1%-12.2%), respectively. The median time spent in hospital during the ASO spell was 19 days (IQR: 14, 24). Over the first year after the ASO patients spent 7 days (IQR: 4-10 days) in hospital in total, decreasing to 1 outpatient day/year beyond the fifth year. In a subgroup with complete risk factor data (n = 652), ASO age, and balloon atrial septostomy (BAS) use were not associated with late mortality and reintervention, but cardiac or congenital comorbidities, low weight, and circulatory/renal support at ASO were. After matching for patient characteristics, BAS followed by ASO and ASO as first procedure, performed within the first 3 weeks of life, had comparable early and late outcomes, including hospital resource utilization.

Conclusions

Mortality and hospital resource utilization are low, while reintervention remains relatively frequent. Early ASO and individualized use of BAS allows for flexibility in treatment choices and a focus on at-risk patients.

The Impact of Prematurity on Morbidity and Mortality in Newborns with Dextro-transposition of the Great Arteries

Prematurity is a risk factor for adverse outcomes after arterial switch operation in newborns with D-TGA (D-TGA). In this study, we sought to investigate the impact of prematurity on postnatal and perioperative clinical management, morbidity, and mortality during hospitalization in neonates with simple and complex D-TGA who received arterial switch operation (ASO). Monocentric retrospective analysis of 100 newborns with D-TGA. Thirteen infants (13.0%) were born premature. Preterm infants required significantly more frequent mechanical ventilation in the delivery room (69.2% vs. 34.5%, p = 0.030) and during the preoperative course (76.9% vs. 37.9%, p = 0.014). Need for inotropic support (30.8% vs. 8.0%, p = 0.035) and red blood cell transfusions (46.2% vs. 10.3%, p = 0.004) was likewise increased. Preoperative mortality (23.1% vs 0.0%, p = 0.002) was significantly increased in preterm infants, with necrotizing enterocolitis as cause of death in two of three infants. In contrast, mortality during and after surgery did not differ significantly between the two groups. Cardiopulmonary bypass times were similar in both groups (median 275 vs. 263 min, p = 0.322). After ASO, arterial lactate (34.5 vs. 21.5 mg/dL, p = 0.007), duration of mechanical ventilation (median 175 vs. 106 h, p = 0.038), and venous thrombosis (40.0% vs. 4.7%, p = 0.004) were increased in preterm, as compared to term infants. Gestational age (adjusted unit odds ratio 0.383, 95% confidence interval 0.179-0.821, p = 0.014) was independently associated with mortality. Prematurity is associated with increased perioperative morbidity and increased preoperative mortality in D-TGA patients.

Predictors of death after receiving a modified Blalock-Taussig shunt in cyanotic heart children: A competing risk analysis

Objective

To determine risk factors affecting time-to-death ≤90 and >90 days in children who underwent a modified Blalock-Taussig shunt (MBTS).

Methods

Data from a retrospective cohort study were obtained from children aged 0–3 years who experienced MBTS between 2005 and 2016. Time-to-death (prior to Glenn/repair), time-to-alive up until December 2017 without repair, and time-to-progression to Glenn/repair following MBTS were presented using competing risks survival analysis. Demographic, surgical and anesthesia-related factors were recorded. Time-to-death ≤90 days and >90 days was analyzed using multivariate time-dependent Cox regression models to identify independent predictors and presented by adjusted hazard ratios (HR) and 95% confidence intervals (CI).

Results

Of 380 children, 119 died, 122 survived and 139 progressed to Glenn/repair. Time-to-death probability (95% CI) within 90 days was 0.18 (0.14–0.22). Predictors of time-to-death ≤90 days (n = 63) were low weight (<3 kg) (HR 7.6, 95% CI:2.8–20.4), preoperative ventilator support (HR 2.7, 95% CI:1.3–5.6), postoperative shunt thrombosis (HR 5.0, 95% CI:2.4–10.4), bleeding (HR 4.5, 95% CI:2.1–9.4) and renal failure (HR 4.1, 95% CI:1.5–10.9). Predictors of time-to-death >90 days (n = 56) were children diagnosed with pulmonary atresia with ventricular septal defect and single ventricle (compared to tetralogy of fallot) (HR 3.2, 95% CI:1.2–7.7 and HR 3.1, 95% CI:1.3–7.6, respectively), shunt size/weight ratio >1.1 vs <0.65 (HR 6.8, 95% CI:1.4–32.6) and longer duration of mechanical ventilator (HR 1.002, 95% CI:1.001–1.004). Shunt size/weight ratio ≥1.0 (vs <1.0) and ≥0.65 (vs <0.65) were predictors for overall time-to-death in neonates and toddlers, respectively (HR 13.1, 95% CI:2.8–61.4 and HR 7.8, 95% CI:1.7–34.8, respectively).

Conclusions

Perioperative factors were associated with time-to-death ≤90 days, whereas particular cardiac defect, larger shunt size/weight ratio, and longer mechanical ventilation were associated with time-to-death >90 days after receiving MBTS. Larger shunt size/weight ratio should be reevaluated within 90 days to minimize the risk of shunt over flow.

Association Between Variation in Preoperative Care Before Arterial Switch Operation and Outcomes in Patients With Transposition of the Great Arteries

BACKGROUND

The arterial switch operation (ASO) is the gold standard operative correction of neonates with transposition of the great arteries and intact ventricular septum, with excellent operative survival. The associations between patient and surgeon characteristics and outcomes are well understood, but the associations between variation in preoperative care and outcomes are less well studied.

METHODS

A multicenter retrospective cohort study of infants undergoing neonatal ASO between January 2010 and September 2015 at hospitals contributing data to the Pediatric Health Information Systems database was performed. The association between preoperative care (timing of ASO, preoperative use of balloon atrial septostomy, prostaglandin infusion, mechanical ventilation, and vasoactive agents) and operative outcomes (mortality, length of stay, and cost) was studied with multivariable mixed-effects models.

RESULTS

Over the study period, 2159 neonates at 40 hospitals were evaluated. Perioperative mortality was 2.8%. Between hospitals, the use of adjuvant therapies and timing of ASO varied broadly. At the subject level, older age at ASO was associated with higher mortality risk (age >6 days: odds ratio, 1.90; 95% CI, 1.11-3.26; P=0.02), cost, and length of stay. Receipt of a balloon atrial septostomy was associated with lower mortality risk (odds ratio, 0.32; 95% CI, 0.17-0.59; P<0.001), cost, and length of stay. Later hospital median age at ASO was associated with higher odds of mortality (odds ratio, 1.15 per day; 95% CI, 1.02-1.29; P=0.03), longer length of stay ( P<0.004), and higher cost ( P<0.001). Other hospital factors were not independently associated with the outcomes of interest.

CONCLUSIONS

There was significant variation in preoperative care between hospitals. Some potentially modifiable aspects of perioperative care (timing of ASO and septostomy) were significantly associated with mortality, length of stay, and cost. Further research on the perioperative care of neonates is necessary to determine whether modifying practice on the basis of the observed associations translates into improved outcomes.

Surgical Age and Morbidity After Arterial Switch for Transposition of the Great Arteries

BACKGROUND

Transposition of the great arteries (TGA) is a complex congenital heart disease that requires early diagnosis as well as advanced surgical repair and postoperative support. This study sought to investigate the impact of surgical timing on early postoperative morbidity.

METHODS

This study reviewed all patients with TGA repaired at a single institution (Skåne University Hospital, Lund, Sweden) by arterial switch operation (ASO) between June 2001 and June 2017. Major postoperative morbidity (MPM) and death within 30 days after ASOs were documented. Patients with double-outlet right ventricle, chromosomal abnormalities, and noncardiac diseases were excluded. MPM was defined as the presence of at least 1 of the following: delayed sternum closure, reoperation, prolonged mechanical ventilation, noninvasive ventilation after extubation, peritoneal dialysis, extracorporeal membrane oxygenation, and readmission.

RESULTS

A total of 241 patients were included, with medians for birth weight, gestational week, and age at surgery of 3.5 kg, 39 weeks, and 5 days, respectively. MPM was encountered in 32.3% of patients. Prematurity (P = .001) and need for aortic arch repair at the time of ASO (P = .04) were associated with a significant increase in MPM. Non-A coronary anatomy, associated ventricular septal defect requiring surgical closure, and fetal diagnosis of TGA had no significant impact on MPM (P = .35, .08, and .21, respectively). There was no significant difference in MPM among the surgical groups (P = .49).

CONCLUSIONS

Early complications after ASO do occur and are mostly associated with prematurity and the need for aortic arch repair. Timing of surgical repair does not seem to influence the rate of these complications.

Ductal Stenting to Retrain the Involuted Left Ventricle in d-Transposition of the Great Arteries

BACKGROUND

Ductal stenting is performed to retrain involuted left ventricles (LVs) in patients with d-transposition of the great arteries and intact ventricular septum (TGA-IVS). However, its efficacy is largely unknown. This study aimed to determine the safety and efficacy of ductal stenting in retraining of the involuted LV in patients with TGA-IVS.

METHODS

This was a single-center, retrospective study. Echocardiographic assessment of the LV geometry, mass, and free wall thickness was performed before stenting and before the arterial switch operation. Patients then underwent the arterial switch operation, and the postoperative outcomes were reviewed.

RESULTS

There were 11 consecutive patients (male, 81.8%; mean age at stenting, 43.11 ± 18.19 days) with TGA-IVS with involuted LV who underwent LV retraining by ductal stenting from July 2013 to December 2017. Retraining by ductus stenting failed in 4 patients (36.3%). Two patients required pulmonary artery banding, and another 2 had an LV mass index of less than 35 g/m². Patients in the successful group had improved LV mass index from 45.14 ± 17.91 to 81.86 ± 33.11g/m² (p = 0.023) compared with 34.50 ± 10.47 to 20.50 ± 9.88 g/m² (p = 0.169) and improved LV geometry after ductal stenting. The failed group was associated with an increased need for extracorporeal support (14.5% vs 50%, p = 0.012). An atrial septal defect-to-interatrial septum length ratio of more than 0.38 was associated with failed LV retraining.

CONCLUSIONS

Ductal stenting is an effective method to retrain the involuted LV in TGA-IVS. A large atrial septal defect (atrial septal defect-to-interatrial septum length ratio >0.38) was associated with poor response to LV retraining.

Population trends in prenatal detection of transposition of great arteries: impact of obstetric screening ultrasound guidelines

OBJECTIVES

Dextro-transposition of the great arteries (d-TGA) is one of the most common critical neonatal heart defects, with a low detection rate antenatally. We sought to evaluate trends in the prenatal detection of d-TGA with or without ventricular septal defect (VSD) in Alberta over the past 13 years, examining the potential impact of ultrasound guidelines incorporating screening of cardiac outflow tracts, updated in 2009-2010 and in 2013, and factors affecting detection of the condition.

METHODS

All fetuses and neonates with d-TGA, with or without VSD, encountered between 2003 and 2015 in the province of Alberta, were identified retrospectively. Clinical records including obstetric ultrasound reports were reviewed. Pregnancy outcome, common referral indications and associated maternal and fetal pathology in affected pregnancies were assessed.

RESULTS

From 2003 to 2015, 127 cases with d-TGA were encountered in Alberta, of which 47 (37%) were detected prenatally. Prenatal detection improved over the study period, from 14% in 2003-2010, to 50% in 2011-2013, and to 77% in 2014-2015. Of the 47 fetuses with a prenatal diagnosis of d-TGA, an indication for fetal echocardiography included abnormal or poorly visualized cardiac outflows with normal four-chamber view in 46 (98%). Comorbidities were identified in 12 mothers, only five of which represented an additional reason for fetal echocardiography referral, and four fetuses had extracardiac pathology.

CONCLUSION

Substantial improvement in the prenatal detection of d-TGA has been observed in Alberta over the past few years, owing to improved screening of cardiac outflow tracts on routine obstetric ultrasound examination in otherwise healthy pregnancies, and has been temporally associated with updated obstetric ultrasound guidelines suggesting that these contributed to optimized screening of affected pregnancies. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Transposition of Great Arteries with Complex Coronary Artery Variants: Time-Related Events Following Arterial Switch Operation

Coronary artery anatomy represents a challenging and, often, determining predictor of outcome in an arterial switch operation (ASO). Impact of specific coronary artery variants, such as single, intramural and inverted, on time-related events following ASO, is, yet, to be determined. We sought to compare early and late outcomes within the group of nonstandard coronary artery variants. Patients who underwent ASO from January 1995 to October 2010 were reviewed. Patients with coronary artery variants other than L1Cx1R2 ("standard" by Leiden classification) were included. Patients with single, intramural and inverted coronary artery variants incorporated in group A. All other nonstandard coronary variants incorporated in group B. Demographics, perioperative variables, early and late outcomes were assessed. Of the 123 ASO, 24 patients (19.5%) with nonstandard coronary variant were studied. Thirteen were in group A and 11 in group B. There were two early deaths (1 in group A and 1 in group B) (p > 0.05). There is one death early after hospital discharge (group A). Mean follow-up was 59.4 ± 55.1 months. There was no structural coronary artery failure after hospital discharge following ASO. Freedom from any reintervention at 8 years was (78.3 ± 9.6%) (p 0.55) with no late neo-aortic or mitral valve intervention. ASO with single, intramural or inverted coronary artery course carries no added longitudinal risk for structural or flow impairment within the group of nonstandard coronary artery variants. There is an early hazard period with no late survival attrition. Aortic arch repair as part of staged strategy prior to ASO might influence early and late outcome.

Recanalisation of the closed ductus arteriosus in a critically ill infant with transposition of the great arteries

We describe the case of an infant who was a late presenter of transposition of the great arteries where we proceeded with ductal stenting to improve oxygenation and left ventricle training. Stenting improved the infant's saturation while keeping the left ventricle well trained for 4 months after the procedure. This report demonstrates that intermediate-term left ventricle training can be achieved via ductal stenting.

D-transposition of the great arteries: the current era of the arterial switch operation

This paper aims to update clinicians on "hot topics" in the management of patients with D-loop transposition of the great arteries (D-TGA) in the current surgical era. The arterial switch operation (ASO) has replaced atrial switch procedures for D-TGA, and 90% of patients now reach adulthood. The Adult Congenital and Pediatric Cardiology Council of the American College of Cardiology assembled a team of experts to summarize current knowledge on genetics, pre-natal diagnosis, surgical timing, balloon atrial septostomy, prostaglandin E1 therapy, intraoperative techniques, imaging, coronary obstruction, arrhythmias, sudden death, neoaortic regurgitation and dilation, neurodevelopmental (ND) issues, and lifelong care of D-TGA patients. In simple D-TGA: 1) familial recurrence risk is low; 2) children diagnosed pre-natally have improved cognitive skills compared with those diagnosed post-natally; 3) echocardiography helps to identify risk factors; 4) routine use of BAS and prostaglandin E1 may not be indicated in all cases; 5) early ASO improves outcomes and reduces costs with a low mortality; 6) single or intramural coronary arteries remain risk factors; 7) post-ASO arrhythmias and cardiac dysfunction should raise suspicion of coronary insufficiency; 8) coronary insufficiency and arrhythmias are rare but are associated with sudden death; 9) early- and late-onset ND abnormalities are common; 10) aortic regurgitation and aortic root dilation are well tolerated; and 11) the aging ASO patient may benefit from "exercise-prescription" rather than restriction. Significant strides have been made in understanding risk factors for cardiac, ND, and other important clinical outcomes after ASO.