Surgical Management of Neonatal Atrioventricular Septal Defect With Aortic Arch Obstruction

A 27-Year Experience with Atrioventricular Septal Defect Correction

This single-center study investigated long-term outcomes after surgical correction of atrioventricular septal defect (AVSD).A total of 248 patients underwent biventricular repair for AVSD between 1995 and 2022. A total of 208 (83.9%) patients had complete (cAVSD), 29 (11.7%) partial (pAVSD), and 11 (4.4%) transitional AVSD (tAVSD). Associated cardiovascular anomalies were present in 88 (35.5%) cases and 61 (24.6%) patients were born prematurely. Median age at repair was 7.1 for cAVSD, 23.7 for pAVSD, and 13 months for tAVSD.Overall survival or reoperation incidence did not differ significantly between AVSD types and improved significantly over surgical eras. Survival of the entire cohort was 88.3% at 10, 83.8% at 15, and 79.6% at 25 years. Prematurity (hazard ratio [HR]: 2.43, p = 0.029), low weight (<4 kg) (HR: 3.05, p = 0.028), and partial cleft closure (HR: 2.43, p = 0.037) were independent risk factors for mortality. Forty-eight patients (19.4%) underwent a total of 64 reoperations over the study period. The main indication for reoperation was left atrioventricular valve regurgitation (LAVVR) with 55/64 procedures. However, 36% of procedures were performed to address several lesions, with left ventricular outflow tract obstruction being the second most common indication. Freedom from reoperation was 78.2, 75.8, and 72.5% at 10, 15, and 25 years, respectively. The incidence of reoperation increased significantly in association with early postoperative LAVVR ≥ I-II° (HR: 2.6, 95% confidence interval [CI]: 1.4-4.7, p = 0.002) and presence of residual cardiac defects (HR: 2.0, 95% CI: 1.1-3.6, p = 0.018).While LAVVR is the main indication for reoperation, a significant proportion of procedures address additional pathologies. Premature patients and those with associated cardiovascular anomalies should receive special attention during postoperative follow-up.

Can we diagnose aortic arch obstruction in a fetus with an atrioventricular septal defect?

BACKGROUND

Aortic arch obstruction and/or coarctation of aorta is uncommon (5-20%) in balanced atrioventricular septal defects. Although technically challenging, prenatal diagnosis of aortic arch obstruction in atrioventricular septal defect is critical for delivery planning and improves prenatal counselling regarding the timing of cardiac surgery. We sought to identify prenatal predictors of coarctation of aorta in atrioventricular septal defect.

METHODS

Retrospective review of patients prenatally diagnosed with atrioventricular septal defect at two institutions.

RESULTS

Ninety-five fetuses with atrioventricular septal defect were identified and sufficient outcome data and diagnostic acoustic windows were available in 62. Six patients (10%) had coarctation of aorta after birth. Among the 38 patients with Trisomy 21, four (11%) had coarctation of aorta. On multivariable analysis, the proximal transverse aortic arch z score and ratio of left:right atrioventricular valve were independent predictors of coarctation of aorta with good interobserver reproducibility. Either proximal transverse aortic arch z score < -2, or ratio of left:right atrioventricular valve <0.7, predicted aortic arch obstruction with 100% sensitivity and 89% specificity.

CONCLUSION

Proximal transverse aortic arch z score and lower ratio of left:right atrioventricular valve diameter are independent predictors of postnatal coarctation of aorta in fetal patients with atrioventricular septal defect. The next step is the prospective application of these parameters to create an algorithm directing fetal counselling in terms of delivery location, and expected timing of surgical interventions.

Staged repair for complete atrioventricular septal defect in patients weighing less than 4.0 kg

OBJECTIVE

This study compared the mortality, left atrioventricular valve-related reoperation, and left atrioventricular valve competence in symptomatic neonates and small infants who underwent staged repair incorporating pulmonary artery banding or primary repair for complete atrioventricular septal defect.

METHODS

Patients weighing less than 4.0 kg at the time of undergoing staged (n = 37) or primary (n = 23) repair for balanced complete atrioventricular septal defect between 1999 and 2022 were reviewed. The mean follow-up period was 9.1 years. Freedom from moderate or greater left atrioventricular valve regurgitation was estimated with the Kaplan-Meier method.

RESULTS

The staged group included smaller children (median weight, 2.9 vs 3.7 kg) and a higher proportion of neonates (41% vs 4%). All patients in the staged group survived pulmonary artery banding and underwent intracardiac repair (median weight, 6.8 kg). After pulmonary artery banding, the severity of left atrioventricular valve regurgitation improved in 10 of 12 patients (83%) without left atrioventricular valve anomaly who had mild or greater left atrioventricular valve regurgitation and a left atrioventricular valve Z score greater than 0. Although survival and freedom from left atrioventricular valve-related reoperation at 15 years (P = .195 and .602, respectively) were comparable between the groups, freedom from moderate or greater left atrioventricular valve regurgitation at 15 years was higher in the staged group (P = .026).

CONCLUSIONS

Compared with primary repair, staged repair for complete atrioventricular septal defect in children weighing less than 4.0 kg resulted in comparable survival and reoperation rates and better left atrioventricular valve competence. Pulmonary artery banding may mitigate secondary left atrioventricular valve regurgitation unless a structural valve abnormality exists. Selective deferred intracardiac repair beyond the neonatal and small-infancy period may still play an important role in low-weight patients.

Single-Stage Surgical Management of Atrioventricular Septal Defects with Coarctation of the Aorta

Surgical options for coarctation of aorta (CoA) with atrioventricular septal defect (AVSD) include single-stage repair vs. staged approach with neonatal CoA repair and delayed AVSD repair. The durability of left atrioventricular valve (LAVV) function after neonatal repair is questioned, and the optimal approach remains controversial. Eighteen CoA-AVSD patients who underwent single-stage repair 2005-2015 by a single surgeon were retrospectively analyzed. Fifteen patients had complete and three had partial AVSD. Birth weight was 3.19 kg (2.17-4.08). Age at surgery was 16 days (6-127). One- and ten-year survival were 80% and 69%. Freedom from reintervention was 60% and 40% at one and ten-year respectively. Reinterventions included relief of left ventricular outflow tract obstruction (LVOTO) (n = 4), repair of cleft LAVV (n = 3), and LAVV and aortic valve replacement (n = 1). Freedom from LAVV reintervention was 85.6% and 66% at 1 and 10 years respectively. There were four deaths: two post-operative and two following hospital discharge. Mortality was due to sepsis in three patients, and heart failure related to LVOTO and LAVV insufficiency in one. At 68-month (0.6-144) follow-up the majority had mild or less LAVV regurgitation, and all had normal LV dimension and systolic function. There was no recurrent arch obstruction. Single-stage surgical repair of CoA-AVSD is feasible and reasonable. Survival and freedom from reintervention in our cohort approximate those outcomes of two-stage repair with durable left AV valve function and no recurrent arch obstruction. These patients are frequently syndromic and demonstrate mortality risk from non-cardiac causes. Consideration of a single-staged approach is warranted for appropriate patients with CoA-AVSD.

Long-term outcome after early repair of complete atrioventricular septal defect in young infants

OBJECTIVE

The long-term outcome after repair of complete atrioventricular septal defect in young infants is still not fully understood. The objective of this study was to evaluate data after repair for complete atrioventricular septal defect over a 25-year period to assess survival and identify risk factors for left atrioventricular valve-related reoperations.

METHODS

A total of 304 consecutive patients underwent surgical correction for complete atrioventricular septal defect between April 1993 and October 2018. The results for young infants (aged <3 months; n = 55; mean age 1.6 ± 0.6 months) were compared with older infants (aged >3 months; n = 249; mean age, 5.1 ± 5.2 months). Mean follow-up was 13.2 ± 7.8 years (median, 14.0 years; interquartile range, 7.0-20.0). The Kaplan-Meier method was used to assess overall survival and freedom from left atrioventricular valve-related reoperation.

RESULTS

Overall, 30-day mortality was 1.0% (3/304) with no difference between young and older infants (P = 1.0). Overall survival in the total population at 20-year follow-up was 95.1% (±1.3%). Independent risk factors for poor survival were the presence of an additional ventricular septal defect (P = .042), previous coarctation of the aorta (P < .001), persistent left superior vena cava (P = .026), and genetic syndromes other than Trisomy 21 (P = .017). Freedom from left atrioventricular valve-related reoperation was 92.6% (±1.7%) at 20 years. There was no significant difference in left atrioventricular valve-related reoperation in young infants compared with older infants (P = .084).

CONCLUSIONS

Our data demonstrated that excellent long-term survival could be achieved with early repair for complete atrioventricular septal defect, and the need for reoperations due to left atrioventricular valve regurgitation was low. Primary correction in patients aged less than 3 months is, when clinically necessary, well tolerated. Palliative procedures can be avoided in the majority of patients.

Pulmonary artery banding in complete atrioventricular septal defect

OBJECTIVES

To analyze outcomes after pulmonary artery banding (PAB) in complete atrioventricular septal defect (AVSD), with a focus on surgical pathway outcome and timing, survival, and atrioventricular valve function.

METHODS

PAB was performed in 50 of 474 infants (11%) from 28 institutions between 2012 and 2018 at a median age of 1.1 months. The median duration of follow-up was 2.1 years. Atrioventricular valve function was assessed by review of pre-PAB and predischarge echocardiograms (median, 9 days postoperatively). Competing-risks methodology was used to analyze the risks for biventricular repair, univentricular repair, and death.

RESULTS

At 2 years, the proportions of patients who underwent biventricular repair, univentricular repair, and death were 68%, 13%, and 12%, respectively, with 8% awaiting definitive repair. After PAB, atrioventricular valve regurgitation decreased in 14 infants and increased in 10, but the distribution of regurgitation severity did not change significantly in the total cohort or subgroups. The intended management plan at PAB was deferred biventricular/univentricular decision (23 infants), 2-stage biventricular repair (24 infants), and univentricular repair (3 infants). Among the 24 infants intended for biventricular repair, 23 achieved biventricular repair and 1 died before repair. Survival at 4 years after biventricular repair among patients with previous PAB (93%) was similar to the 4-year survival of the patients who underwent primary biventricular repair (91%; n = 333).

CONCLUSIONS

PAB is a successful strategy in complete AVSD to bridge to biventricular repair and has similar post-biventricular repair survival to primary biventricular repair. Changes in atrioventricular valve regurgitation after PAB were variable.

Right-Dominant Unbalanced Atrioventricular Septal Defect: Echocardiography in Surgical Decision Making

BACKGROUND

Management of right-dominant atrioventricular septal defect (AVSD) remains a challenge given the spectrum of ventricular hypoplasia. The purpose of this study was to assess whether reported echocardiographic indices and additional measurements were associated with operative strategy in right-dominant AVSD.

METHODS

A blinded observer retrospectively reviewed preoperative echocardiograms of patients who underwent surgery for right-dominant AVSD (January 2000 to July 2013). Ventricular dimensions, atrioventricular valve index (AVVI; left valve area/right valve area), and right ventricular (RV)/left ventricular (RV/LV) inflow angle were measured. A second observer measured a subset of studies to assess agreement. Pearson correlation analysis was performed to examine the relationship between ventricular septal defect size (indexed to body surface area) and RV/LV inflow angle in systole. A separate validation cohort was identified using the same methodology (August 2013 to July 2016).

RESULTS

Of 46 patients with right-dominant AVSD (median age, 1 day; range, 0-11 months), overall survival was 76% at 7 years. Twenty-eight patients (61%) underwent single-ventricle palliation and had smaller LV dimensions and volumes, AVVIs (P = .005), and RV/LV inflow angles in systole (P = .007) compared with those who underwent biventricular operations. Three patients undergoing biventricular operations underwent transplantation or died and had lower indexed LV end-diastolic volumes compared with the remaining patients (P = .005). Interobserver agreement for the measured echocardiographic indices was good (intraclass correlation coefficient = 0.70-0.95). Ventricular septal defect size and RV/LV inflow angle in systole had a strong negative correlation (r = -0.7, P < .001). In the validation cohort (n = 12), RV/LV inflow angle in systole ≤ 114° yielded sensitivity of 100% and AVVI ≤ 0.70 yielded sensitivity of 88% for single-ventricle palliation.

CONCLUSIONS

Mortality remains high among patients with right-dominant AVSD. RV/LV inflow angle in systole and AVVI are reproducible measurements that may be used in conjunction with several echocardiographic parameters to support suitability for a biventricular operation in right-dominant AVSD.