Risk Factors for Reoperation After Arterial Switch Operation

Excellent Survival With a Focus on Pulmonary Artery Reinterventions After the Arterial Switch Operation

Background: We sought to evaluate the outcomes in patients who underwent the arterial switch operation (ASO) over a 20-year period at a single institution. Methods: The current study is a retrospective review of 180 consecutive patients who underwent the ASO for biventricular surgical correction of dextro-transposition of the great arteries (d-TGA) between 2002 and 2022. Results: Among 180 patients, 121 had TGA-intact ventricular septum, 47 had TGA-ventricular septal defect and 12 had Taussig-Bing Anomaly (TBA). The median follow-up time was 6.7 years (interquartile range: 3.9-8.7 years). There were five early (2.8%) and one late (0.6%) mortality. Survival was 96.6% at one year and beyond. Reoperations were performed in 31 patients (17%). Taussig Bing Anomaly was found to increase the risk of reoperation by 17 times (P < .0001). A total of 37 (21%) patients underwent 53 reinterventions (14 surgical procedures, 39 catheter interventions) specifically addressing pulmonary artery (PA) stenosis. Freedom from PA reintervention was 97%, 87%, 70%, and 55% at 1, 5, 10, and 15 years, respectively. By bivariable analysis, TBA (P = .003, odds ratio [OR]: 6.4, 95% confidence interval [CI]: 1.9-21.7), mild PA stenosis at discharge (P ≤ .001, OR: 6.1, 95% CI: 2.7-13.6), and moderate or severe PA stenosis at discharge (P ≤ .001, OR: 12.7, 95% CI: 5-32.2) were identified as predictors of reintervention on PA. In the last follow-up of 174 survivors, 24 patients (14%) had moderate or greater PA stenosis, two (1%) had moderate neoaortic valve regurgitation, and 168 were New York Heart Association status I. Conclusions: Our results demonstrated excellent survival and functional status following the ASO for d-TGA; however, patients remain subject to frequent reinterventions especially on the pulmonary arteries.

Reoperations in Adolescents and Adults After Prior Arterial Switch Operation: The Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis

BACKGROUND

Arterial switch operation (ASO) has supplanted physiologic repairs for transposition of the great arteries and related anomalies. As survival rates have increased, so has the potential need for cardiac reoperations to address ASO-related complications arising later in life.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010-2021) was reviewed to assess prevalence and types of cardiac reoperations for patients aged ≥10 years with prior ASO for transposition of the great arteries or double-outlet right ventricle/transposition of the great arteries type. A hierarchical stratification designating 13 procedure categories was established a priori by investigators. Each eligible surgical hospitalization was assigned to the single highest applicable hierarchical category. Outcomes were compared across procedure categories, excluding hospitalizations limited to pacemaker-only and mechanical circulatory support-only procedures. Variation during the study period in relative proportions of left heart vs non-left heart procedure category encounters was assessed.

RESULTS

There were 698 cardiac surgical hospitalizations for patients aged 10 to 35 years at 100 centers. The most common left heart procedure categories were aortic valve procedures (n = 146), aortic root procedures (n = 117), and coronary artery procedures (n = 40). Of 619 hospitalizations eligible for outcomes analysis, major complications occurred in 11% (67/619). Discharge mortality was 2.3% (14/619). Year-by-year analysis of surgical hospitalizations reveals substantial growth in numbers for the aggregate of all procedure categories. Growth in relative proportions of left heart vs non-left heart procedures was significant (P = .0029; Cochran-Armitage trend test).

CONCLUSIONS

This large multicenter study of post-ASO reoperations beyond early childhood documents year-over-year growth in total reoperations. Left-sided heart procedures recently had the highest rate of rise. These observations have implications for counseling, surveillance, and management.

Prevalence of Branch Pulmonary Artery Reintervention Following the Arterial Switch Operation

BACKGROUND

The arterial switch operation (ASO) is the preferred surgical procedure used to correct dextro-transposition of the great arteries. A known complication of the ASO is branch pulmonary arteries (PAs) stenosis, which may require reintervention. Our goal is to determine the frequency of reintervention after the ASO and any factors associated with reintervention.

METHODS

This was a single center, retrospective study of infants who underwent the ASO from June 6, 2011 to February 21, 2021. The primary outcome was the prevalence of reintervention on the PAs following the ASO.

RESULTS

Sixty-eight infants were analyzed; 9 (13%) patients had 10 reinterventions. The mean age at time of the ASO was 6.52 ± 6.63 days; weight was 3.34 ± 0.57 kg. Those with a reintervention had a longer bypass time (P = .047). Mean age at reintervention was 0.80 ± 0.72 years; mean time from the ASO to reintervention was 0.799 ± 0.717 years. Six surgical procedures, two stent placements, and four balloon angioplasties were performed on a total of 13 branch PAs. There was no increased risk for reintervention on the right versus left PA. After reintervention, there was an improvement in the minimal PA diameter and echo gradient. There were no adverse events or mortality related to the reintervention. Mean follow-up was 6.17 ± 2.94 years.

CONCLUSION

The prevalence of branch PA reintervention following the ASO in our cohort was 13%. There is an association between longer cardiopulmonary bypass time and reintervention. After reintervention, there was an increase in PA diameter and a decrease in echo gradient.

Simultaneous Double Balloon Dilatation for Supravalvar Pulmonary Obstruction After Arterial Switch Operation

The optimal approach for supravalvar right ventricular outflow tract obstruction(RVOTO) after arterial switch operation(ASO) is unclear. The results of percutaneous balloon dilatation have been variable. We report the results of simultaneous double balloon dilation for RVOTO after ASO. Sixteen patients (1.3(0.7-3.8) years; 9.8(8.1-15.1) kgs underwent the procedure at 14(8-44.5) months after ASO. Salient technical features included placement of balloons over stiff guide-wires positioned in both branch pulmonary arteries to enable dilation of the distal-most main pulmonary artery (MPA) with high inflation pressures (~ 12-14 atmospheres) and short inflation-deflation cycles. Effective balloon size was based on the PA annulus or MPA distal to the narrowing. The final balloon: narrowest segment diameter ratio was 2.7. Following dilation, the right ventricle to systemic systolic pressure ratio decreased from 0.9 ± 0.18 to 0.52 ± 0.16 (p  < 0.001) and mean RVOT gradient from 78 ± 18 to 34 ± 13.9 mmHg (p < 0.001). Narrowest diameter improved from 5.4 ± 2.2 to 9.2 ± 2.2 mm. There were no major complications. Two patients with inadequate relief (final RV-systemic ratios: 1.03 and 0.7) were referred for surgery. At median follow up of 9 months, IQR 7-22, range 5-73, others are free of re interventions with median RVOT gradient of 42, IQR 27-49, range 21-55 mmHg. The immediate and short-term follow up results of double balloon dilatation for supravalvar RVOTO is encouraging and may avoid the need for repeat surgery in the majority of patients. Further follow up is needed to determine the long-term durability of the results.

From Other Journals: A Review of Recent Articles by Our Editorial Team

In this review we provide a brief description of recently published articles addressing topics relevant to pediatric cardiologists. Our hope is to provide a summary of the latest articles published recently in other journals in our field. The articles address (1) a summary of a scientific statement of the American Heart Association for diagnosis and treatment of myocarditis, (2) development of a perioperative risk score for in-hospital mortality after cardiac surgery in adults with congenital heart disease, (3) using a machine learning algorithm to predict cardiopulmonary deterioration in patients in the interstage period 1-2 h in advance using hospital monitor generated data, (4) risk factors for reoperation after the arterial switch operation, (5) the effect of mitochondrial transplantation for cardiogenic shock in pediatric patients, (6) comparing outcomes of primary or staged repair in tetralogy of Fallot with pulmonary atresia.