Echocardiography in the Diagnosis and Management of Tricuspid Atresia

This review focuses on the utility of echocardiographic studies in the diagnosis of tricuspid atresia (TA) and in its management. Tricuspid atresia is a cyanotic congenital heart defect (CHD) accounting for nearly 1.5% of all CHDs. It is generally classified according to the morphology of the atretic tricuspid valve and associated heart defects. Following the description of the anatomic features of TA, echocardiographic features characteristic for TA were illustrated. Subsequent to a review of palliative and corrective procedures to treat TA, echocardiographic evaluation at each stage of Fontan was detailed. The role of echocardiography in the assessment of cardiac defects responsible for interstage mortality was also addressed. It was concluded that echo-Doppler studies are useful in the diagnosis and management of TA.

Abstract 13407: Trends in Discharge Prescription of Digoxin After Norwood Operation: An Analysis of Data From the Pediatric Health Information Systems Database (PHIS)

Background: Quality improvement efforts have focused on reducing interstage mortality for infants with hypoplastic left heart syndrome (HLHS). In 2016 two publications reported that digoxin use was associated with reduced interstage mortality. The degree to which these findings have affected real world practice has not been evaluated. Methods: A multicenter retrospective cohort study of rates of digoxin prescription at discharge was performed of neonates with HLHS surviving to discharge without transplant from 1/2006-12/2018 at PHIS hospitals. A difference in difference analysis was performed using mixed effects models to adjust for measurable covariates (known arrhythmia, prematurity, renal insufficiency, etc.) with the hypothesis that the likelihood of digoxin prescription increased after 1/2016. Inter-hospital practice variation was measured, calculating the median odds ratio (MOR). Likelihood of furosemide and aspirin prescriptions were studied as falsification tests. Results: Over the study period 6091 subjects from 35 hospitals were included. Likelihood of receiving digoxin, furosemide, and aspirin are depicted (Figure). After adjusting for measurable covariates, discharge after 1/2016 was associated with increased odds of receiving digoxin (OR: 3.9, p<0.001). No association was seen between date of discharge and furosemide (p=0.26) or aspirin (p=0.12). Prior to 1/2016, the likelihood of receiving digoxin was decreasing (OR: 0.9 per year, p<0.001), while after 1/2016 the likelihood has increased (OR: 2.4 per year, p<0.001). Significant inter-hospital variation in the likelihood of receiving digoxin was seen (MOR=3.5, p<0.001 with no significant difference before and after 2016). Conclusion: The use of digoxin increased after publication of data about potential benefit in the interstage period. However, despite concerted quality improvement efforts, there is persistent large magnitude inter-hospital variation in practice.

Decreasing Interstage Mortality After the Norwood Procedure: A 30‐Year Experience

Background The superior cavo‐pulmonary connection was introduced at our institution in 1988 for infants undergoing surgery for hypoplastic left heart syndrome. Patients with hypoplastic left heart syndrome remain at high risk for mortality in the time period between the Norwood procedure and the superior cavo‐pulmonary connection. The primary objectives of this study were to compare interstage mortality across 4 eras and analyze factors that may impact interstage mortality. Methods and Results Patients with hypoplastic left heart syndrome who underwent the Norwood procedure, were discharged from the hospital, and were eligible for superior cavo‐pulmonary connection between January 1, 1988, and December 31, 2017, were included. The study period was divided into 4 eras based on changes in operative or medical management. Mortality rates were estimated with 95% CIs. Adjusted and unadjusted logistic regression models were used to identify risk factors for mortality. There were 1111 patients who met the inclusion criteria. Overall, interstage mortality was 120/1111 (10.8%). Interstage mortality was significantly lower in era 4 relative to era 1 (4.6% versus 13.4%; P =0.02) during the time that age at the superior cavo‐pulmonary connection was the lowest (135 days; P <0.01) and the interstage monitoring program was introduced. In addition, use of the right ventricle to pulmonary artery shunt was associated with decreased interstage mortality ( P =0.02) and was more routinely practiced in era 4. Conclusions During this 30‐year experience, the risk of interstage mortality decreased significantly in the most recent era. Factors that coincide with this finding include younger age at superior cavo‐pulmonary connection, introduction of an interstage monitoring program, and increased use of the right ventricle to pulmonary artery shunt.

In-hospital interstage improves interstage survival after the Norwood stage 1 operation

OBJECTIVES The interstage mortality rate after a Norwood stage 1 operation remains 12–20% in current series. In-hospital interstage facilitates escalation of care, possibly improving outcome. METHODS A retrospective study was designed for hypoplastic left heart syndrome (HLHS) and HLHS variants, offering an in-hospital stay after the Norwood operation until the completion of stage 2. Daily and weekly examinations were conducted systematically, including two-dimensional and speckle-tracking echocardiography. Primary end points included aggregate survival until the completion of stage 2 and interstage freedom from escalation of care. Moreover, we calculated the sensitivity and specificity of speckle-tracking echocardiographic myocardial deformation in predicting death/transplant after the Norwood procedure. RESULTS Between 2015 and 2019, 33 neonates with HLHS (24) or HLHS variants (9) underwent Norwood stage 1 (31) or hybrid palliation followed by a comprehensive stage 2 operation (2). Stage 1 Norwood–Sano was preferred in 18 (54.5%) neonates; the classic Norwood with Blalock–Taussig shunt was performed in 13 (39.4%) neonates. The Norwood stage 1 30-day mortality rate was 6.2%. The in-hospital interstage strategy was implemented after Norwood stage 1 with a 3.4% interstage mortality rate. The aggregate Norwood stage 1 and interstage Kaplan–Meier survival rate was 90.6 ± 5.2%. Escalation of care was necessary for 5 (17.2%) patients at 2.5 ± 1.2 months during the interstage for compromising atrial arrhythmias (2), Sano-shunt stenosis (1) and pneumonia requiring a high-frequency oscillator (2); there were no deaths. A bidirectional Glenn (25) or a comprehensive-Norwood stage 2 (2) was completed in 27 patients at 4.7 ± 1.2 months with a 92.6% survival rate. The overall Kaplan–Meier survival rate is 80.9 ± 7.0% at 4.3 years (mean 25.3 ± 15.7 months). An 8.7% Δ longitudinal strain 30 days after Norwood stage 1 had 100% sensitivity and 81% specificity for death/transplant. CONCLUSIONS In-hospital interstage facilitates escalation of care, which seems efficacious in reducing interstage Norwood deaths. A significant reduction of longitudinal strain after Norwood stage 1 is a strong predictor of poor outcome.

Power of a Learning Network in Congenital Heart Disease

Background: The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) formed to improve outcomes in infants with hypoplastic left heart syndrome. The collaborative sought to (1) decrease mortality, (2) reduce growth failure, and (3) reduce hospital readmissions due to major medical problems during the interstage period between discharge following stage 1 palliation (S1P) and admission for stage 2 palliation (S2P). Methods: The NPC-QIC is a learning network, coproduced by parents and clinicians, of 65 pediatric cardiology centers that contribute clinical data on care processes and outcomes to a shared registry. The adapted Breakthrough Series Model structure brings teams together regularly to review data, share lessons, and plan improvements. Outcomes are monitored using statistical process control methods. Results: Between 2008 and 2016, interstage mortality decreased by >40%, from 9.5% to 5.3%. Identification and use of a nutrition bundle led to improved infant growth, with a 28% reduction in interstage growth failure. The rate of serious hospital readmissions was low and did not significantly change. Importantly, a formed partnership with the parent group Sisters by Heart fostered the coproduction of tools and strategies and an emphasis on data transparency and outcomes. Conclusions: The NPC-QIC’s initial efforts led to improvements in interstage growth and mortality. The NPC-QIC has modeled the use of data for improvement and research, the value of coproduction with parents, and the concept “all teach, all learn,” demonstrating the power of the learning network model.