Critical care outcomes in pulmonary atresia and intact ventricular septum undergoing single-ventricle palliation

Outcomes of infants with pulmonary atresia with intact ventricular septum listed for heart transplantation: A multi-institutional study

BACKGROUND

Management of infants with pulmonary atresia/intact ventricular septum (PA/IVS) is variable. Because of higher mortality in more severe forms, heart transplant (HT) is an acceptable approach, but waitlist and post-transplant outcomes are unclear. This study compared outcomes of infants with PA/IVS vs. other single ventricle (SV) anatomies listed for HT.

METHODS

Data from the Pediatric Heart Transplant Society (1993-2018) were analyzed for survival and risk factors for mortality.

RESULTS

Of 1617 SV infants, 300 had PA/IVS (19%) and 1317 had other SV (81%). Overall, 1-, 5-, and 10-year survival was higher among PA/IVS (74%, 65%, 61%) versus other SV infants (62%, 54%, 50%, p = .004). While waitlist mortality was similar between groups (p = .09), PA/IVS was an independent predictor of improved waitlist survival (HR 0.68, p = .03), and PA/IVS infants had higher incidence of waitlist removal (8% vs. 5.5%, p = .03), most commonly for being "too well." Post-transplant survival was superior among PA/IVS versus other SV infants (1- and 5-year survival 93% and 81% vs. 80% and 71%, p < .0001). Risk factors for PA/IVS waitlist mortality (2008-2018) included extracorporeal membrane oxygenation and mechanical ventilation. Prior aortopulmonary (AP) shunt among PA/IVS infants was associated with improved waitlist survival.

CONCLUSIONS

Overall survival among PA/IVS infants listed for HT exceeds that of other SV infants with PA/IVS identified as an independent predictor of improved waitlist and post-transplant survival. Prior AP shunt among listed PA/IVS infants was associated with improved waitlist outcomes, though, which may reflect a listing selection bias.

Procedural Outcomes of Pulmonary Atresia Intact Ventricular Septum in Neonates: A Multicenter Study

BACKGROUND

Multicenter contemporary data describing short-term outcomes following initial interventions of neonates with pulmonary atresia intact ventricular septum (PA-IVS) are limited. This multicenter study aims to describe characteristics and outcomes of PA-IVS neonates following their initial catheter or surgical intervention and identify factors associated with major adverse cardiac events (MACE).

METHODS

Neonates with PA-IVS who underwent surgical or catheter intervention between 2009-2019 in 19 centers were reviewed. Risk factors for MACE, defined as cardiopulmonary resuscitation, mechanical circulatory support, stroke, or in-hospital mortality, were analyzed using multivariable logistic regression model.

RESULTS

We reviewed 279 neonates: 79 (28%) underwent right ventricular decompression, 151 (54%) underwent systemic-to-pulmonary shunt or ductal stent placement only, 36 (13%) underwent right ventricular decompression with shunt or ductal stent placement, and 11 (4%) underwent transplantation. MACE occurred in 57 patients (20%): 26 (9%) received mechanical circulatory support, 37 (13%) received cardiopulmonary resuscitation, 16 (6%) suffered stroke, 23 (8%) died. The presence of two major coronary artery stenoses (adjusted OR: 4.99; 95% CI: 1.16-21.39) and lower weight at first intervention (adjusted OR: 1.52, 95% CI: 1.01-2.27) were significantly associated with MACE. Coronary ischemia was the most frequent presumed mechanism of death (n=10).

CONCLUSIONS

In a multicenter cohort, one in five neonates with PA-IVS experienced MACE following their initial intervention. Patients with two major coronary artery stenoses or lower weight at time of initial procedure were most likely to experience MACE and warrant vigilance during pre-intervention planning and post-intervention management.

Are early palliative procedures providing an adequate long-term benefit in young cyanotic infants from developing countries, despite advances in surgery and interventions?

OBJECTIVES

Ductal stents, right ventricular outflow tract stents, and aortopulmonary shunts are used to palliate newborns and infants with reduced pulmonary blood flow. Current long-term outcomes of these palliations from resource-restricted countries are unknown.

METHODS

This single-centre, retrospective, observational study analysed the technical success, immediate and late mortality, re-interventions, and length of palliation in infants ≤5 kg who underwent aortopulmonary shunts, ductal, and pulmonary outflow stents. Patients were grouped by their anatomy.

RESULTS

There were 69 infants who underwent one of the palliations. Technical success was 90% for aortopulmonary shunts (n = 10), 91% for pulmonary outflow stents (n = 11) and 100% for ductal stents (n = 48). Early mortality within 30 days in 12/69 patients was observed in 20% after shunts, 9% after pulmonary outflow stents, and 19% after ductal stents. Late mortality in 11 patients was seen in 20% after shunts, 18% after outflow stents, and 15% after ductal stents. Seven patients needed re-interventions; two following shunts, one following outflow stent, and four following ductal stents for hypoxia. Among the anatomical groups, 10/12 patients with pulmonary atresia, intact ventricular septum survived after valvotomy and ductal stenting. Survival to Glenn shunt after ductal stent for pulmonary atresia, intact ventricular septum and diminutive right ventricle was very low in two out of eight patients, but very good (100%) for other univentricular hearts. Among 35 patients with biventricular lesions, 22 survived to the next stage.

CONCLUSIONS

Cyanotic infants, despite undergoing technically successful palliation had a high inter-stage mortality irrespective of the type of palliation. Duct stenting in univentricular hearts and in pulmonary atresia with an intact ventricular septum and adequate sized right ventricle tended to have low mortality and better long-term outcome. Completion of biventricular repair after palliation was achieved only in 63% of patients, reflecting unique challenges in developing countries despite advances in intensive care and interventions.

Pulmonary Atresia With an Intact Ventricular Septum: Preoperative Physiology, Imaging, and Management

Pulmonary atresia with intact ventricular septum (PA-IVS) is a rare complex cyanotic congenital heart disease with heterogeneous morphological variation. Prenatal diagnosis allows for developing a safe plan for delivery and postnatal management. While transthoracic echocardiography allows for detailed delineation of the cardiac anatomy, additional imaging modalities such as computed tomography, magnetic resonance imaging, and catheterization may be necessary to further outline features of the cardiac anatomy, specifically coronary artery anatomy. The size of the tricuspid valve and right ventricular cavity as well as the presence of right ventricle–dependent coronary circulation help to dichotomize between biventricular repair versus univentricular palliation or heart transplantation, as well as predicting the expected survival. The delineation and understanding of these features help to dictate both medical and surgical management.

Pulmonary atresia/intact ventricular septum: influence of coronary anatomy on single-ventricle outcome

BACKGROUND

We investigated the influence of coronary artery abnormalities on outcome in patients with pulmonary atresia/intact ventricular septum (PA-IVS) for planned single-ventricle palliation.

METHODS

Catheterization and medical records were reviewed in patients with PA-IVS for planned single-ventricle palliation at our institution between 2000 and 2012. Primary outcome was death or transplantation. Patients with confirmed or strong suspicion of stenosis in 2 or more main coronary arteries or coronary ostial atresia were defined as having right ventricle-dependent coronary circulation (RVDCC); those with stenosis of 1 main vessel or normal anatomy were defined as having non-RVDCC.

RESULTS

Of 58 patients with PA-IVS, 17 (30%) underwent single-ventricle palliation. Ten (59%) had RVDCC (3 with ostial atresia) and 7 (41%) had non-RVDCC. Median follow-up time was 8.2 years (0 months-11.3 years), with 1 patient in each group lost to follow-up. Five patients with RVDCC died, including the 3 patients with ostial atresia, and 1 underwent transplantation at 6 months of life. No deaths occurred after second-stage palliation. Three of the 4 surviving patients with RVDCC completed a Fontan operation, and 2 of these patients had evidence of cardiac ischemia on follow-up. No deaths occurred among patients with non-RVDCC. Kaplan-Meier analysis demonstrated significantly better survival in patients with non-RVDCC (100%) than in patients with RVDCC (40%) (p = 0.026).

CONCLUSIONS

In patients with PA-IVS undergoing single-ventricle palliation, RVDCC is associated with high early mortality, especially with coronary ostial atresia. There should be early consideration of transplantation in neonates with RVDCC. Patients with non-RVDCC undergoing single-ventricle palliation have excellent long-term outcomes, with no mortality seen in this series.

Stenting the patent ductus arteriosus in duct-dependent pulmonary circulation: techniques, complications and follow-up issues

Maintaining ductal patency in duct-dependent congenital heart lesions by implantation of coronary stents is an alternative to systemic pulmonary shunt in selected cases and lesions with suitable anatomy. This article focuses on the procedure as the initial palliation in duct-dependent pulmonary circulation, its associated pitfalls and complications. A good understanding of the diverse duct morphology is paramount prior to stenting of the ductus. Long tortuous duct, insufficiently constricted ductus at the pulmonary end and ductus with associated branch pulmonary artery stenosis at the site of insertion are not suitable for stenting. Durability of palliation is generally inferior to a surgical shunt and this may dictate earlier definitive surgical repair. Acceleration of branch pulmonary artery stenosis in certain ductal morphology limits its general applicability. Bioabsorbable and biodegradable stents may offer some solution to this problem.