Does Down syndrome influence the outcomes of congenital cardiac surgery? A systematic review and meta-analysis

BACKGROUND

Congenital cardiac surgery for individuals with Down syndrome (DS) has historically occurred at a reduced frequency. Little data are available regarding long-term post-congenital cardiac surgical outcomes. Limited sample sizes and clinical heterogeneity require a pooled analysis approach.

AIMS

To compare long-term outcomes post-congenital heart surgery between adults with and without DS.

METHODS

Databases (Medline, Embase, and PubMed) were searched utilizing terms related to DS and congenital heart disease.Studies that enrolled adults (>18 years) with operated congenital heart disease and compared long-term outcomes with respect to DS presence were included. All study designs were included, but those with limited/peri-operative follow-up, non-English texts, case studies, and literature reviews were excluded.Blinded screening, data extraction, and quality assessment were independently conducted by two reviewers. QUIPS criteria were used for risk of bias analysis. Both random- and fixed-effects models were used for meta-analysis.

RESULTS

A total of 23 studies (n = 10 466) were included. Risk of bias was frequently high due to unblinded retrospective study designs and analyses limited in adjustment for other prognostic factors.Meta-analysis demonstrated no effect of DS on long-term mortality [hazard ratio (HR) 0.86, 95% confidence interval (95% CI) 0.6-1.23], to a maximum described follow-up of 38 years. Lower cardiac reoperation risk (HR 0.6, 95% CI 0.46-0.78) for individuals with DS was found on pooled analysis. Meta-analysis was limited by between-study variation.

CONCLUSION

DS does not affect post-congenital cardiac surgical survival in adulthood. Reduced reoperation may reflect challenges in assessing functional and symptomatic status and/or concerns regarding perceived reoperation difficulties or likely benefits.

Reoperations After Repair for Atrioventricular Septal Defects: >25 Years Experience at a Single Center

Our aim was to evaluate the total burden of reoperations after previous repair for atrioventricular septal defects, including long-term survival and identify risk factors for reoperation. All patients with surgical correction for atrioventricular septal defect (AVSD) 1993- 2020 underwent a follow-up in October 2020. Clinical data were obtained by retrospective review and evaluated with Kaplan-Meier and competing risk analysis. Of 477 patients who underwent initial repair, 53 patients (11.1%) underwent a total of 82 reoperations. The perioperative mortality at reoperation was 3.8% (2/53). There were no late deaths (0/51) during follow-up. In patients requiring reoperation for left atrioventricular valve regurgitation, a re-repair was performed in 90% (26/29) at first attempt. Estimated overall survival was 96.2 ± 2.6% (95% CI 91.2-100) in the Any reoperation group and 96.7 ± 0.9% (95% CI 94.9-98.5) in the No reoperation group at 20 years (P = 0.80). The cumulative incidence function of Any reoperation (with death as competing risk) was 13.0% (95% CI 9.4-16.5) at 20 years. Independent risk factors for Any reoperation included severe mitral regurgitation after primary repair (HR 40.7; 95% CI 14.9-111; P < 0.001). The risk of perioperative mortality in AVSD patients undergoing reoperation was low in the present study. Long-term survival was very good and not significantly different when compared to patients who did not need reoperation. Re-repair for left atrioventricular valve regurgitation was possible in most cases and showed long-term durability. Our data suggest that reoperations after primary repair of AVSD have very good long-term outcomes when performed at a high-volume pediatric cardiac surgery center.

Long-Term Outcome Up To 40 Years after Single Patch Repair of Complete Atrioventricular Septal Defect in Infancy or Childhood

Objectives  Patients with repaired complete atrioventricular septal defect (CAVSD) represent an increasing portion of grown-ups with congenital heart disease. For repair of CAVSD, the single-patch technique has been employed first. This technique requires division of the bridging leaflets, thus, among other issues, long-term function of the atrioventricular valves is of particular concern.

Methods  Between 1978 and 2001, 100 consecutive patients with isolated CAVSD underwent single-patch repair in our institution. Hospital mortality was 11%. Primary endpoints were clinical status, atrioventricular valve function, and freedom from reoperation in long term. Follow-up was obtained contacting the patient and/or caregiver, and the referring cardiologist.

Results  Eighty-three patients were eligible for long-term follow-up (21.0 ± 8.7, mean ± standard deviation [21.5; 2.1–40.0, median; min–max] years after surgical repair). Actual long-term mortality was 3.4%. Quality of life (QoL; self- or caregiver-reported in patients with Down syndrome) was excellent or good in 81%, mild congestive heart failure was present in 16%, moderate in 3.6% as estimated by New York Heart Association classification. Echocardiography revealed normal systolic left ventricular function in all cases. Regurgitation of the right atrioventricular valve was mild in 48%, mild–moderate in 3.6%, and moderate in 1.2%. The left atrioventricular valve was mildly stenotic in 15% and mild to moderately stenotic in 2%; regurgitation was mild in 54%, mild to moderate in 13%, and moderate in 15% of patients. Freedom from left atrioventricular-valve-related reoperation was 95.3, 92.7, and 89.3% after 5, 10, and 30 years, respectively. Permanent pacemaker therapy, as an immediate result of CAVSD repair ( n  = 7) or as a result of late-onset sick sinus syndrome ( n  = 5), required up to six reoperations in single patients. Freedom from pacemaker-related reoperation was 91.4, 84.4, and 51.5% after 5, 10, and 30 years, respectively.

Conclusion  Up to 40 years after single-patch repair of CAVSD, clinical status and functional results are promising, particularly, in terms of atrioventricular valve function. Permanent pacemaker therapy results in a life-long need for surgical reinterventions.

Double orifice and atrioventricular septal defect: dealing with the zone of apposition†

OBJECTIVES

A double orifice of the left atrioventricular valve (LAVV) associated with atrioventricular septal defects (AVSD) can significantly complicate surgical repair. This study reports our experience of AVSD repair over 3 decades, with special attention to the zone of apposition (ZoA) of the main orifice, and presents a technique of hemivalve pericardial extension in specific situations.

METHODS

We performed a retrospective study from 1987 to 2016 on 1067 patients with AVSD of whom 43 (4%) had a double orifice, plus 2 additional patients who required LAVV pericardial enlargement. Median age at repair was 1.3 years. Mean follow-up was 8.2 years (1 month-32 years).

RESULTS

Associated abnormalities of the LAVV subvalvular apparatus were found in 7 patients (5 parachute LAVV and 2 absence of LAVV subvalvular apparatus). ZoA was noted in 4 patients (9%): partially closed in 15 (35%) and completely closed in 24 (56%). Four patients required, either at first repair or secondarily, a hemivalve enlargement using a pericardial patch without closure of the ZoA. The early mortality rate was 7% (n = 3), all before 2000. Two patients had unbalanced ventricles and the third had a single papillary muscle. There were no late deaths. Six patients (14%) required 7 reoperations (3 early and 4 late reoperations) for LAVV regurgitation and/or dysfunction, of whom 4 (9%) required mechanical LAVV replacement (all before 2000). Freedom from late LAVV reoperation was 97% at 1 year, 94% at 5 years and 87% at 10, 20 and 30 years. Unbalanced ventricles (P = 0.045), subvalvular abnormalities (P = 0.0037) and grade >2 LAVV postoperative regurgitation (P = 0.017) were identified as risk factors for LAVV reoperations. Freedom from LAVV mechanical valve replacement was 95% at 1 year, 90% at 5 years and 85% at 10, 20 and 30 years. An anomalous LAVV subvalvular apparatus was identified as a risk factor for mechanical valve replacement (P = 0.010). None of the patients who underwent LAVV pericardial extension had significant LAVV regurgitation at the last follow-up examination.

CONCLUSIONS

Repair of AVSD and double orifice can be tricky. Preoperative LAVV regurgitation was not identified as an independent predictor of surgical outcome. LAVV hemivalve extension appears to be a useful and effective alternate surgical strategy when the ZoA cannot be closed.

Early and midterm outcomes of a modified single-patch technique for repairing complete atrioventricular septal defect in children and adults

OBJECTIVES

The "modified single-patch" technique (Nunn's technique) has become more widely adopted, especially in small infants with common atrioventricular septal defect (CAVSD). In this study, we retrospectively reviewed our surgical experiences of the "modified single-patch" technique with CAVSD patients, including newborns and adults, to reveal the early and midterm clinical results.

METHODS

There were 233 cases diagnosed with CAVSD undergoing biventricular repair in our hospital from June 2009 to 2016. A total of 197 cases (84.5%) with the "modified single-patch" technique were enrolled in the final analysis, including type A in 106 cases (53.8%), type B in 13 cases (6.6%), type C in 15 cases (7.6%), and intermediate type in 63 cases (32%). Major associated cardiovascular malformations included five cases of unroofed coronary sinus syndrome with LSVC (UCS), five cases of coarctation of the aorta and one case of translocation of the great artery. The median age at operation of the studied 197 cases was 44.3 ± 103.3 months (ranging from 18 days to 58 years old), including two newborns. Detailed information on the "modified single-patch" procedure was described previously, and the other cardiac malformations were repaired simultaneously with surgical repair.

RESULTS

There were 14 (7.1%) early deaths and 3 (1.5%) late deaths at 3 months and 1 year after the initial operation, respectively. The total mortality rate was 8.1%, and there was no significant difference in mortality among the different age groups (P = .291). Five patients (2.5%) underwent reoperation because of severe mitral insufficiency (MI), and another patient was reoperated for left ventricular outflow tract obstruction 3 years after the initial surgery. Long-term survival in the <3 months group was significantly lower than that in the group of older children (1-18 years old). Of the 180 survivors who were followed up for at least 1 year, the proportion of severe MI began to drop from 26.2% before the operation to 13.8% just 1-week postoperation and continued to decline to the lowest level, 3.4%, at 3 months postoperation. However, MI began to rebound at 3 months and reached 20.8% at 1-year postoperation. The rebound of MI was evident in the (3 months, 6 months) age group and the >18 years age group. However, compared to the preoperation situation, the proportion of severe tricuspid insufficiencies decreased each month from 24.8% to 0.0% until 3 months after the operation and remained at a relatively low level within 1 year after surgery.

CONCLUSIONS

In our experience, age is not a limitation of the modified single-patch technique, and patients even in adults with surgical indications can apply this technique. In older children and adults, we should pay more attention to atrioventricular valve annuloplasty. Infants may suffer from severe residual left atrioventricular valve regurgitation, especially in the <3 months age group, so we should improve postoperative follow-up work during infancy.

Surgical repair of partial atrioventricular defect

Long-term survival rate of patients operated for partial atrioventricular (AV) canal is lower than that of the general population, and late complications are relatively significant: between 10 and 30% of operated patients present with left AV valve regurgitation, and up to 25% have to be reoperated for valve repair or replacement, left ventricular outflow tract obstruction or residual atrial septal defect. Because the left AV valve regurgitation is the most common complication following surgery, technical details in the surgical management of the mitral valve are the most important aspects of this procedure; for example, the decision to close the cleft and to perform an annuloplasty. The presence of mitral valve anomalies in 7-28% of the cases complicates further the surgical management of these valves. This article will describe in detail the operative technique of partial AV canal repair, and review the relevant literature.

Partial and intermediate atrioventricular septal defects without major associated cardiac anomalies

Partial and intermediate atrioventricular septal defects (p-i AVSDs) constitute approximately 20-40% of all AVSDs. Children with p-i AVSDs are usually asymptomatic and typically undergo surgery at the preschool age or earlier if the signs of heart failure have developed. Surgical treatment for repair of p-i AVSDs has been successful for more than 60 years and is mainly directed towards closing septal defects, and maintaining or creating competent, non-stenotic left and/or right atrioventricular valves. By most measures, the outcomes of surgical management of p-i AVSDs have improved over the last 5 decades. In spite of significantly reduced mortality, the need for reoperation and long-term morbidity remains an issue in some patients from this population. The purpose of this article is to review current options and outcomes concerning the surgical management of the p-AVSD and i-AVSD variants without major associated cardiac malformations.