Xin Tao Ye

Long-term outcomes of single-ventricle palliation for unbalanced atrioventricular septal defects: Fontan survivors do better than previously thought

Background: Single‐ventricle palliation (SVP) for children with unbalanced atrioventricular septal defect (uAVSD) is thought to carry a poor prognosis, but limited data have been reported. Methods: We performed a retrospective review of children with uAVSD who underwent SVP at a single institution. Data were obtained from medical records and correspondence with general practitioners and cardiologists. Results: Between 1976 and 2016, a total of 139 patients underwent SVP for uAVSD. A neonatal palliative procedure was performed in 83.5% of these patients (116 of 139), and early mortality occurred in 11.2% (13 of 116). Ninety‐four patients underwent stage II palliation, with an early mortality of 6.4% (6 of 94). Eighty patients (57.6%) underwent Fontan completion, with an early mortality of 3.8% (3 of 80). Interstage mortality was 11.7% (12 of 103) between stages I and II and 17.0% (15 of 88) between stage II and Fontan. Long‐term survival was 66.5% (95% confidence interval [CI], 57.9%‐73.9%) at 5 years, 64.4% (95% CI, 55.5%‐72.0%) at 15 years, and 57.8% (95% CI, 47.5%‐66.8%) at 25 years. Survival post‐Fontan was 94.9% (95% CI, 86.9%‐98.0%) at 5 years, 92.0% (95% CI, 80.6%‐96.8%) at 15 years, and 82.4% (95% CI, 61.5%‐92.6%) at 25 years. Risk factors associated with death or transplantation were aortic atresia (hazard ratio [HR], 5.3; P = .03) and hypoplastic aortic arch (HR, 2.5; P = .02). Atrioventricular valve operations were required in 31.7% of the patients (44 of 139), with 31.8% of them (14 of 44) requiring a further operation. Conclusions: Children undergoing SVP for uAVSD have substantial mortality, with <60% survival at 25 years. However, survival of children who achieve Fontan completion is better than has been reported previously.

Successful atrioventricular valve repair improves long-term outcomes in children with unbalanced atrioventricular septal defect

Background: Atrioventricular valve regurgitation is a significant cause of morbidity and mortality in patients with unbalanced atrioventricular septal defect. However, knowledge of the outcomes of atrioventricular valve repair in children with unbalanced atrioventricular septal defect and univentricular physiology is limited. Methods: We conducted a retrospective review of all patients with unbalanced atrioventricular septal defect treated with single‐ventricle palliation who underwent atrioventricular valve surgery at The Royal Childrens Hospital. Results: Between 1976 and 2016, 139 children with unbalanced atrioventricular septal defect underwent single‐ventricle palliation, of whom 31.7% (44/139) required atrioventricular valve surgery. Repair of the atrioventricular valve was attempted in 97.7% (43/44) of patients, of whom 4.7% (2/43) were converted to replacement during the initial operation. Replacement of the atrioventricular valve without attempted repair was performed in 2.3% (1/44) of patients. Early mortality was 18.2% (8/44). Freedom from death or transplantation at 10 years was 66.0% (95% confidence interval, 49.1–78.5) and at 20 years was 53.3% (95% confidence interval, 32.1–70.6). In multivariable analysis, significant predischarge atrioventricular valve regurgitation (hazard ratio, 6.4; P = .002), age less than 1 year (hazard ratio, 8.3; P = .01), and repair before stage II palliation (hazard ratio, 3.4; P = .04) were associated with death. Freedom from reoperation at 10 years was 61.9% (95% confidence interval, 41.9–76.8) and at 20 years was 56.3% (95% confidence interval, 35.3–72.8). Moderate or greater atrioventricular valve regurgitation at discharge was associated with an increased risk of reoperation (hazard ratio, 1.8; P = .03). Of transplant‐free survivors, atrioventricular valve regurgitation was less than moderate in 60.0% (15/25) at the most recent follow‐up. Conclusions: Atrioventricular valve surgery in patients with unbalanced atrioventricular septal defect is associated with substantial mortality and a high rate of reoperation. Successful atrioventricular valve repair is associated with better survival and freedom from reoperation.

Long-term outcomes of reoperations following repair of partial atrioventricular septal defect

OBJECTIVES Partial atrioventricular septal defect (pAVSD) is repaired with excellent long-term survival. However, up to 25% of patients require reoperations. This study reviews results of reoperation following pAVSD repair at a single institution. METHODS From 1975 to 2012, 40 patients (16%, 40/246) underwent reoperation following pAVSD repair at the study institution. The data were retrospectively reviewed. RESULTS The mean time to reoperation was 5.4 ± 5.8 years. The most common reoperations were left atrioventricular valve (LAVV) surgery (78%, 31/40) and resection of left ventricular outflow tract obstruction (20%, 8/40). The most common cause for LAVV surgery was regurgitation through the cleft (58%, 18/31), followed by central regurgitation (29%, 9/31). Most cases of LAVV regurgitation were treated by repair (77%, 24/31), rather than replacement (23%, 7/31). Since the introduction of a patch augmentation technique for LAVV repair in 1998, the rate of repair has increased from 54 to 94% (P = 0.012). The early mortality rate was 2.5% (1/40). The survival rate was 90% (95% CI: 76-96) at 10 years and 83% (95% CI: 60-94) at 20 years. The rate of freedom from further reoperation was 66% (95% CI: 46-80) at 10- and 20-year follow-up. CONCLUSIONS The most common cause for reoperation following pAVSD repair was LAVV regurgitation through the LAVV cleft. Reoperation is performed with survival comparable to that of primary pAVSD repair, yet the rate of further reoperations remains high. The patch augmentation technique for LAVVR has significantly increased the rate of successful LAVV repair.

Ventricular assist devices for the failing univentricular circulation

ABSTRACT Introduction: Improved survival following single ventricle palliation has led to a large population of patients with a univentricular circulation, many of whom develop heart failure. Increasing experience with ventricular assist devices (VAD) in children has paved the way for VAD support in those with failing univentricular circulation. Areas covered: The use of VADs to support the failing univentricular circulation is a relatively new concept. Most studies have focused on supporting patients with the failing systemic ventricle. There are limited reports of VAD support of the pulmonary circulation in patients with Fontan failure despite preserved ventricular function. None of the current VADs have been designed to support the pulmonary circulation. Novel low-pressure, high-flow pumps, specifically designed to support the pulmonary circulation, are under development. Expert commentary: The failing univentricular circulation is one of the great challenges in the field of congenital heart disease. While current VADs are designed to support the systemic circulation, many patients require support of the pulmonary circulation. A fully implantable VAD for support of the pulmonary circulation as destination therapy would be beneficial for patients with preserved systolic function, but must have low energy requirements, negligible risk of stroke and low risk of device thrombosis and failure.

Propensity score matched analysis of partial atrioventricular septal defect repair in infancy

Objective Partial atrioventricular septal defect (pAVSD) is usually repaired between 2 and 4 years of age with excellent results. Repair during infancy has been associated with poorer outcomes. However, most infants in reported series had heart failure or significant left atrioventricular valve (LAVV) regurgitation. The impact of surgery during infancy on outcomes remains unclear. Methods All children at three institutions who underwent repair of pAVSD from 1975 to 2015 were included. Infants (aged <1 year) were compared with older children in a propensity score matched analysis. Variables used to generate propensity scores were: failure to thrive, congestive heart failure, preoperative LAVV regurgitation, associated congenital heart disease, sex and the presence of trisomy 21. Results pAVSD repair was performed on 430 children, 17.4% (75/430) were infants. Infants (mean age 0.5±0.3 years) had higher rates of LAVV regurgitation, heart failure and additional cardiac malformations than older children (mean age 4.7±3.5 years). At 30 years, survival for infants was 82.1% (95% CI 70.1% to 89.6%) compared with 95.7% (95% CI 91.3% to 97.9%) in older children (P<0.001). Propensity score matching yielded 52 well-matched pairs. Survival at 30 years was 87.9% (95% CI 75.0% to 94.4%) for infants compared with 98.1% (95% CI 87.1% to 99.7%) for older children (P=0.04). There was no significant difference in freedom from reoperation between the groups. Conclusions Despite matching for risk factors, survival after repair of pAVSD during infancy is lower than that when repair is performed in older children, with no difference in reoperation rates. This suggests that elective repair of pAVSD should be deferred until after infancy.

Does biventricular conversion bring survival benefits to patients with an unbalanced atrioventricular septal defect

We read with great interest the recent paper by Nathan et al. [1] published in this journal. The authors presented a cohort of 212 patients with unbalanced atrioventricular septal defects (uAVSDs), comparing the results of 3 different surgical strategies: single-ventricle palliation (SVP; 82 patients), biventricular repair (67 patients) and biventricular conversion or recruitment (BiVC/BiVR; 63 patients). They reported significantly better survival with both biventricular repair and BiVC/BiVR strategies compared with SVP. However, their comparison was biased in favour of the BiVC/BiVR group in several ways. Their time series analysis began at the time of first stage palliation for SVP patients, while it began at the time of complete repair for BiVR/ BiVC patients, introducing a substantial survivorship bias. All patients who died prior to conversion were counted in the SVP group, leaving a selected group of survivors to undergo BiVC/BiVR. Furthermore, patients who underwent SVP had higher rates of RV dominance (86.6% vs 61.9%), which had previously been shown as a risk factor for death in SVP [2]. The SVP group also had a much greater proportion of neonates (68.3% vs 3.2%), pulmonary vein disease (31.7% vs 22.2%) and associated cardiac anomalies (43.9% vs 27.0%), all of which have been associated with mortality. It is likely that the highly selected group undergoing BiVC/BiVR would have had similarly good results with the Fontan circulation. In Melbourne, SVP is performed for patients with uAVSD who are not candidates for initial biventricular repair. We have recently published the longterm outcomes of 139 uAVSD patients who underwent SVP [3]. We observed a similar attrition to Nathan et al. in the overall cohort, with a survival rate of 61.8% at 15 years. However, patients who achieved Fontan completion had much better results than previously thought, with 83.5% freedom from death and Fontan takedown at 15 years. This is similar to the results for BIVC/BiVR reported by Nathan et al. [1], and it is likely that this cohort includes a similar degree of survivorship bias. Importantly, we observed that atrioventricular valve (AVV) regurgitation is a major contributor to morbidity and mortality observed in these patients [4, 5]. Patients with AVV regurgitation who achieved successful repair had much better outcomes than those with a significant residual regurgitation [4]. Our focus is on improving the outcomes of AVV repair in these patients, as we believe this will be the key to improved survival. The work by Nathan et al. is important, and their results are encouraging. However, we emphasize that palliation with the Fontan circulation remains an important option for these patients. Advancements in techniques for repairing the AVV might further improve the outcomes for patients with uAVSD who undergo SVP.

From cellular senescence to regeneration: A quest for the holy grail for the next generation of surgeons?

From the Department of Cardiothoracic Surgery, The Royal Children’s Hospital, The University of Melbourne and the Murdoch Children’s Research Institute, Melbourne, Victoria, Australia. Disclosures: Authors have nothing to disclose with regard to commercial support. Received for publication April 28, 2017; accepted for publication May 11, 2017. Address for reprints: Igor E. Konstantinov, MD, PhD, FRACS, The Royal Children’s Hospital, Flemington Rd, Parkville, Melbourne, Victoria 3029, Australia (E-mail: igor.konstantinov@rch.org.au). J Thorac Cardiovasc Surg 2017;-:1-2 0022-5223/

Long-Term Outcome After Pulmonary Artery Banding In Children With Atrioventricular Septal Defects

36.00 Crown Copyright 2017 Published by Elsevier Inc. on behalf of The American Association for Thoracic Surgery http://dx.doi.org/10.1016/j.jtcvs.2017.05.036 Accumulation of senescent, senescence-associated b-galactosidase–positive, cells appears to play a key role in the initiation of regeneration processes. Improving immune clearance of senescent cells may result in regeneration of the damaged tissue.