Early Complete Atrioventricular Canal Repair Yields Outcomes Equivalent to Late Repair

Predictors of post-operative left atrioventricular valve regurgitation in pediatric patients with complete atrioventricular canal defects

BACKGROUND

In infants with complete atrioventricular canal (CAVC) defects, post-operative left atrioventricular valve regurgitation (LAVVR) is a known major cause of morbidity and mortality and a common indication for re-operation. However, there is scarce data to identify risk factors for poor outcomes. Our study aims to find echocardiographic characteristics that predict post-operative LAVVR at discharge and 1-year follow-up.

METHODS

Retrospective cohort study of patients with initial CAVC repair at our hospital who were followed for 1 year between 2013 and 2022. Patients with major co-morbid conditions were excluded. Serial echocardiograms were reviewed. Anatomic details, quantitative and qualitative measure of LAVVR including the number of regurgitant jets, regurgitant jet length and vena contracta width, and ventricular function were collected. The time points measured include pre-operative transthoracic echocardiogram (TTE), post-operative transesophageal echocardiogram (PO-TEE), routine protocol based post-operative day 1 (POD1) TTE, discharge TTE and 1-year post-operative (1yPO) TTE. Paired t-tests, chi-square analysis, and linear regression analysis were performed comparing measured variables to LAVVR outcomes.

RESULTS

Fifty-two patients were included; 92% had Trisomy 21. The majority were classified as Rastelli A (71%), others Rastelli C (29%). Only two patients had moderate or greater LAVVR pre-operatively. The mean age at repair was 125 ± 44 days. Pre-operative LAVVR was the only significant predictor of LAVVR severity at 1 year after backward stepwise regression. Of those with < moderate LAVVR on PO-TEE, 20% had worsening to ≥ moderate at discharge, but only 9% remained that way at 1 year. Of those with ≥ moderate LAVVR on PO-TEE, 40% improved to < moderate by 1 year. Two patients who worsened at 1 year, both secondary to likely cleft suture dehiscence. Only one patient required reoperation in the immediate post-operative period secondary to severe LAVVR due to suture dehiscence. Routine protocol-based POD1 echo did not have any association with altered outcomes.

CONCLUSION

Pre-operative LAVVR was the only significant predictor of LAVVR severity at 1 year. A significant percentage (40%) of patient with ≥ moderate LAVVR on PO-TEE improved to < moderate by 1 year. Furthermore, routine protocol-based POD1 echo did not have any association with altered outcomes.

Anatomic considerations in the management of complete atrioventricular canal

OBJECTIVE

Patients with complete atrioventricular canal have a variable clinical course prior to repair. Many patients balance their circulations well prior to elective repair. Others manifest clinically significant pulmonary over circulation early in life and require either palliative pulmonary artery banding or complete repair. The objective of this study was to assess anatomic features that impact the clinical course of patients.

METHODS

In total, 222 patients underwent complete atrioventricular canal repair between 2012 and 2022 at a single institution. Twenty-seven (12%) patients underwent either pulmonary artery banding (n = 15) or complete repair (n = 12) at less than 3 months of age (Group 1). The remaining 195 (88%) underwent repair after 3 months of age (Group 2). Patient records and imaging were reviewed.

RESULTS

The median post-operative length of stay following complete repair was 25 [7,46] days for those patients in Group 1 and 7 [5,12] days for those in Group 2 (p < 0.0001). There was relative hypoplasia of left-sided structures in Group 1 versus Group 2. Mean z-score for the ascending aorta was -1.2 (±0.8) versus -0.3 (±0.9) (p < 0.0001), the aortic isthmus was -2.1 (±0.8) versus -1.4 (±0.8) (p = 0.005). The pulmonary valve to aortic valve diameter ratio was median 1.47 [1.38,1.71] versus 1.38 [1.17,1.53] (p 0.008).

CONCLUSIONS

Echocardiographic evaluation of the systemic and pulmonary outflow of patients with complete atrioventricular canal may assist in predicting the clinical course and need for early repair vs pulmonary artery banding.

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.

Long-term results following atrioventricular septal defect repair

BACKGROUND

Atrioventricular septal defects (AVSD) represent 4-7% of congenital cardiac malformations. Definitive early repair is favored over prior pulmonary artery banding and delayed definitive repair in many centers. The aim of this study was to analyze long-term outcomes following AVSD repair over a 21-year period.

METHODS

A total of 202 consecutive patients underwent surgical AVSD correction between June 1999 and December 2020. Surgery was performed using the double-patch technique. The study data were prospectively collected and retrospectively analyzed. Primary outcomes were In-hospital mortality and overall long-term freedom from reoperation.

RESULTS

Median age at operation was 120 days (IQR 94-150), median weight was 5.0 kg (4.2-5.3). None of the patients died within the first 30 postoperative days. In-hospital mortality was 0.5% (1/202 patients). Median follow-up was 57 months (11-121). Overall freedom from reoperation at 5, 10 and 15 years was 91.8%, 86.9% and 86.9%, respectively.

CONCLUSION

AVSD repair with the double-patch technique is a safe and effective procedure with good early postoperative outcomes and low long-term reoperation rates.

Modified single-patch repair for atrioventricular septal defects results in good functional outcomes in the absence of deep ventricular septal defects

OBJECTIVES

We compared 2-patch repair (TP) with modified single-patch repair (MSP) for complete atrioventricular septal defects and evaluated their effect on the left atrioventricular valve (LAVV) competence. We also identified risk factors for unfavorable functional outcomes.

METHODS

This retrospective study included 118 patients with complete atrioventricular septal defects who underwent intracardiac repair from 1998 to 2020 (MSP: 69; TP: 49). The median follow-up period was 10.4 years. The functional outcome of freedom from moderate or greater LAVV regurgitation (LAVVR) was estimated using the Kaplan-Meier method.

RESULTS

The hospital mortality was 1.7% (2/118) and late mortality was 0.8% (1/118). Eight patients required LAVV-related reoperation (MSP: 4; TP: 4) and none required left ventricular outflow tract-related reoperation. In the MSP group without LAVV anomaly, the receiver operating characteristic curve analysis revealed that the ventricular septal defect (VSD) depth was strongly associated with moderate or greater postoperative LAVVR, with the best cutoff at 10.9 mm. When stratified according to the combination of intracardiac repair type and VSD depth, the MSP-deep VSD (VSD depth >11 mm) group showed the worst LAVV competence among the 4 groups (P = .002). According to multivariate analysis, weight <4.0 kg, LAVV anomaly, and moderate or greater preoperative LAVVR were independent risk factors for moderate or greater postoperative LAVVR, whereas MSP was not a risk factor.

CONCLUSIONS

Postoperative LAVVR remains an obstacle to improved functional outcomes. MSP provides LAVV competence similar to TP unless deep VSD is present. The surgical approach should be selected on the basis of anatomical variations, specifically VSD depth.

Teaching the Modified Single-Patch Technique for Complete Atrioventricular Septal Defect

Understanding the morphology of atrioventricular septal defects and learning the operative strategies for their repair is one of the more difficult tasks for congenital cardiac surgery residents to master. The modified single-patch technique for several reasons lends itself to being a strategy that is relatively easy to teach residents. It has shorter cross-clamp and bypass times than the standard two-patch technique, which allows more time for the instructor to safely take the resident through the case. The steps of the operation are quite standard and broadly applicable to the wide variety of cardiac morphologies found in children with atrioventricular septal defects. The purpose of this review is to carefully point out the technical details of each step of the modified single-patch technique focusing on teaching the resident surgeon. The ease of teaching this excellent technique is just another reason to use the modified single-patch technique.

Association of atrial septal fenestration with outcomes after atrioventricular septal defect repair

OBJECTIVE

During repair of atrioventricular septal defect (AVSD), surgeons might leave an atrial level shunt when concerned about postoperative physiology, or as part of routine practice. However, the association of fenestration with outcomes is unclear. We sought to determine factors associated with mortality after biventricular repair of AVSD.

METHODS

We included 581 patients enrolled from 32 Congenital Heart Surgeons' Society institutions from January 1, 2012, to June 1, 2020 in the Congenital Heart Surgeons' Society AVSD cohort. Parametric multiphase hazard analysis was used to identify factors associated with mortality. A random effect model was used to account for possible intersite variability in mortality.

RESULTS

An atrial fenestration was placed during repair in 133/581 (23%) patients. Overall 5-year survival after repair was 91%. Patients who had fenestration had an 83% 5-year survival versus 93% for those not fenestrated (P < .001). Variables associated with mortality in multivariable hazard analysis included institutional diagnosis of ventricular unbalance (hazard ratio [HR], 2.7 [95% confidence interval (CI): 1.5-4.9]; P = .003), preoperative mechanical ventilation (HR, 4.1 [95% CI, 1.3-13.1]; P = .02), atrial fenestration (HR, 2.8 [95% CI, 1.5-4.9]; P < .001), and reoperation for ventricular septal defect (HR, 4.0 [95% CI, 1.3-13.1]; P = .002). There was no difference in measures of ventricular unbalance for comparisons of fenestrated with nonfenestrated patients. No significant interinstitution variability in mortality was observed on the basis of the random effect model (P = .7).

CONCLUSIONS

An atrial communication at biventricular repair of AVSD is associated with significantly reduced long-term survival after adjusting for other known associated factors, including unbalance. These findings might challenge the routine practice of fenestration.

Longer Exposure to Left-to-Right Shunts Is a Risk Factor for Pulmonary Vein Stenosis in Patients with Trisomy 21

We conducted a study to determine whether patients born with Trisomy 21 and left-to-right shunts who develop pulmonary vein stenosis (PVS) have a longer exposure to shunt physiology compared to those who do not develop PVS. We included patients seen at Boston Children’s Hospital between 15 August 2006 and 31 August 2017 born with Trisomy 21 and left-to-right shunts who developed PVS within 24 months of age. We conducted a retrospective 3:1 matched case–control study. The primary predictor was length of exposure to shunt as defined as date of birth to the first echocardiogram showing mild or no shunt. Case patients with PVS were more likely to have a longer exposure to shunt than patients in the control group (6 vs. 3 months, p-value 0.002). Additionally, PVS patients were also more likely to have their initial repair ≥ 4 months of age (81% vs. 42%, p-value 0.003) and have a gestational age ≤ 35 weeks (48% vs. 13%, p-value 0.003). Time exposed to shunts may be an important modifiable risk factor for PVS in patients with Trisomy 21.

Surgical Management for Complete Atrioventricular Septal Defects: A Systematic Review and Meta-Analysis

A meta-analysis is performed for a comparison of outcomes between the modified one-patch repair (MPR) and two-patch repair (TPR) for complete atrioventricular septal defects (CAVSD). Electronic databases, including PubMed, Scopus, Embase, and Cochrane Library were searched systematically for the literature which aimed mainly at comparing the therapeutic effects for CAVSD administrated by MPR and TPR. Corresponding data sets were extracted and two reviewers independently assessed the risks of bias. Meta-analysis was performed using Revman 5.3 and Stata 12.0. Fifteen studies meeting the inclusion criteria were included, involving 2076 subjects in total. It was observed that MPR was associated with shorter cardiopulmonary bypass (CPB) and aortic cross-clamp (ACC) times, as compared with TPR. However, no statistical differences were found in terms of size of ventricular septal defects (VSD), reoperation, mortality, implantation of permanent pacemakers, and length of ventilation, hospital and intensive care unit stay. As compared with TPR, MPR is superior in terms of ACC and CPB. However, with regard to reoperation, mortality, length of ventilation, ICU and hospital stay and permanent pacemakers implantation, no significant differences are found between these two procedures. MPR is likely to apply to younger infants with faster completion of surgery. Surgery is recommended between 3 and 6 months of age.

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.

"Repair of common atrioventricular junction in isolation and when associated with other congenital heart defects"

Management of atrioventricular septal defects has grown leaps and bounds since the first correction of this malformation. Main reasons considered for the improvement are good understanding of lesion anatomy, precise preoperative diagnosis including imaging, progress in surgical technique, myocardial protection, and post-operative care. In this article we review the anatomy, pathophysiology, clinical features, associations, diagnosis, surgical therapy, complications, and results of atrioventricular septal defects.

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.

Radiologist's Guide to Diagnosis of Fetal Cardiac Anomalies on Prenatal Ultrasound Imaging

Congenital cardiac anomalies are a common finding during prenatal anatomical survey ultrasound examination. Cardiac anomalies are a major cause of prenatal and neonatal mortality and morbidity. If the anomaly is not lethal, most would require surgical correction. Therefore, early recognition of these abnormalities is essential for parental counseling and delivery planning, as well as analysis of neonatal treatment options. Although prenatal ultrasound plays an important role in identification of such anomalies, diagnosis and interpretation of imaging findings require familiarity and knowledge of the common imaging features. In this article, we provide a comprehensive review of ultrasound appearance of common fetal cardiac anomalies.

Contemporary Outcomes After Repair of Isolated and Complex Complete Atrioventricular Septal Defect

BACKGROUND

Contemporary outcomes of complete atrioventricular septal defect (CAVSD) repair, particularly for defects with associated abnormalities, is unclear. The goal of this study is to report an all-inclusive experience of CAVSD repair using a consistent surgical approach.

METHODS

All patients undergoing CAVSD repair between 1995 and 2016 at our institution were included. Patients were divided into 2 groups: isolated and complex (tetralogy of Fallot, aortic arch repair, double outlet right ventricle, and total anomalous pulmonary venous return). Survival and reoperation were analyzed using log-rank test and Gray's test, respectively. Multivariable analysis was performed with Cox regression.

RESULTS

Overall, 406 patients underwent repair: 350 (86%) isolated and 56 (14%) complex CAVSD (tetralogy of Fallot: 34, double outlet right ventricle: 7, aortic arch repair: 12, total anomalous pulmonary venous return: 3). Median age at repair was 5 months (range, 10 days to 16 years); 339 (84%) had trisomy 21. A 2-patch repair was used in 395 (97%) and the zone of apposition was completely closed in 305 (75%). Perioperative mortality was 2% and 4% in the isolated and complex groups, respectively. Perioperative mortality since 2006 was 0.9%. Median follow-up was 7 years. Overall 10-year survival and incidence of any reoperation were 92% and 11%, respectively. Complex anatomy was not a risk factor for mortality (p = 0.35), but it was for reoperation (hazard ratio [HR]: 2.6; p < 0.01). Risk factors for left atrioventricular valve reoperation were a second bypass run (HR: 2.7) and preoperative moderate or worse regurgitation (HR: 2.3).

CONCLUSIONS

Mortality after CAVSD repair is low, yet reoperation remains a significant problem. Repair of complex CAVSD can be performed with similar mortality rates.

A review of the Nunn modified single patch technique for atrioventricular septal defect repair

Atrioventricular septal defect (AVSD) is a common congenital cardiac surgical problem. Over the years, younger and smaller infants are having operations for this condition before irreversible cardio pulmonary changes occur. Traditionally a single or two patch techniques have been used to repair this defect. However, in the past two decades an innovative method of modified single patch technique popularized by Dr. Graham Nunn has gained worldwide popularity. This review discusses the origin, surgical principles, technique and outcomes of this method, popularly known as Nunn or Australian technique. Research comparing the modified single patch technique to classic single and double patch techniques has shown good preservation of atrioventricular valve function, no residual ventricular septal defect (VSDs), low incidence of left ventricular outflow obstruction, preserved conduction, easy reproducibility, and improved perioperative and long-term mortality.

Surgical Considerations in Atrioventricular Canal Defects

Atrioventricular canal defects represent a diverse and challenging group of defects. Timing and surgical technique is greatly dependent on morphology of the valve as well as symptoms. Surgical options for repair of these defects are reviewed and presented below.