Adaptive Growth of the Ductus Arteriosus and Aortic Isthmus in Various Ductus-Dependent Complex Congenital Heart Diseases.

BACKGROUND: The ductus arteriosus (DA) is critical in maintaining postnatal circulation in neonates with obstructed systemic circulation (OSC) and pulmonary circulation (OPC). We hypothesized that the size of the DA and aortic isthmus (AoI) undergoes adaptive growth in utero to counteract the hemodynamic challenges in these congenital heart diseases (CHD). METHODS: Postnatal echocardiograms of neonates diagnosed prenatally with ductal-dependent CHD who were started on prostaglandins within 24 h of birth were reviewed. We assessed the cross-sectional area of the aortic valve opening, pulmonary valve opening, AoI, and DA by calculating (diameter)2/body surface area. Neonates were classified into OSC or OPC then subgrouped depending upon the patency of semilunar valves: OSC with and without aortic atresia (OSC-AA and OSC-nAA, respectively) and OPC with and without pulmonary atresia (OPC-PA and OPC-nPA, respectively). RESULTS: Ninety-four cases were studied. The DA in OSC was significantly larger than OPC, and the DA in OSC-AA was significantly larger than OSC-nAA. The size of the AoI was significantly larger in OPC than OSC and larger in OSC-AA than OSC-nAA. Within the OSC-nAA group, there was no significant difference in the size of the DA, AoI, or pulmonary valve opening between those with retrograde flow (RF) at the AoI and without (nRF) except the aortic valve opening was significantly larger in nRF. All groups had comparable cross-sectional areas of systemic output. CONCLUSIONS: Our findings suggest that DA and AoI show compensatory growth to maintain critical blood flow to vital organs against primary anatomical abnormalities in ductus-dependent CHD. (249 words).

Transesophageal pacing studies reduce readmission but prolong initial admission in infants with supraventricular tachycardia: A cost-comparison analysis.

Background: Supraventricular tachycardia (SVT) is a common arrhythmia. Infants with SVT are often admitted to initiate antiarrhythmics. Transesophageal pacing (TEP) studies can be used to guide therapy prior to discharge. Objective: The objective of this study was to investigate the impact of TEP studies on length of stay (LOS), readmission, and cost in infants with SVT. Methods: This was a 2-site retrospective review of infants with SVT. One site (Center TEPS) utilized TEP studies in all patients. The other (Center NOTEP) did not. Patients with structural heart disease, patients with gestational age <34 weeks, and patients diagnosed after 6 months were excluded. At Center TEPS, repeat TEP studies were performed after titration of medication until SVT was not inducible. Primary endpoints were LOS and readmission for breakthrough SVT within 31 days of discharge. Hospital reimbursement data were utilized for cost-effectiveness analysis. Results: The cohort included 131 patients, 59 in Center TEPS and 72 in Center NOTEP. One patient was readmitted in Center TEPS vs 17 in Center NOTEP (1.6% vs 23.6%; P ≤ .001). Median LOS was longer for Center TEPS at 118.0 (interquartile range [IQR] 74.0-189.5) hours vs Center NOTEP at 66.9 (IQR 45.5-118.3) hours (P = .001). Twenty-one patients had multiple TEP studies. Median length of readmission for Center NOTEP was 65 (IQR 41-101) hours. Including readmission costs, utilization of TEP studies resulted in a probability-weighted cost of $45,531 per patient compared with $31,087 per patient without TEP studies. Conclusion: Utilization of TEP studies was associated with decreased readmission rates but longer LOS and greater cost compared with SVT management without TEP studies.

Outcomes in Infants with Supraventricular Tachycardia: Risk Factors for Readmission, Recurrence and Ablation.

Supraventricular tachycardia (SVT) is the most common arrhythmia in infants. Once diagnosed, infants are admitted for antiarrhythmic therapy and discharged after observation. There are limited data on risk factors for readmission and readmission rates, while on medication. The objective of this study was to investigate risk factors for readmission and outcomes in infants diagnosed with SVT. This is a single-center retrospective study over a 10-year period of infants under 6 months of age with documented SVT. Infants with congenital heart disease requiring surgical or catheter intervention, gestational age less than 32 weeks or diagnosis of atrial flutter or fibrillation were excluded. The primary outcome was readmission within 31 days of hospital discharge. Long term need for ablation and eventual discontinuation of medications were assessed. Ninety patients were included. Beta blockers were the initial therapy in 66 and 28 required a medication change. Nineteen were readmitted within 31 days of discharge. The only clinical factor associated with early readmission was presence of ventricular pre-excitation (6/19 vs. 8/71, p = 0.03). Patients who were readmitted within 31 days had a longer length of treatment (12 [11.5, 22.0] vs. 10 [7.5, 12.0] months, p = 0.007) and were more likely to undergo ablation (4/19 vs. 2/71, p = 0.017). In this cohort of infants with SVT, readmission was common and ventricular pre-excitation was identified as a risk factor for readmission. Infants who were readmitted within 31 days of discharge had longer length of antiarrhythmic therapy and were more likely to undergo catheter ablation.

Low-dose prostaglandin E1 is safe and effective for critical congenital heart disease: is it time to revisit the dosing guidelines?

INTRODUCTION: Prostaglandin E1 is used to maintain ductal patency in critical congenital heart disease (CHD). The standard starting dose of prostaglandin E1 is 0.05 µg/kg/minute. Lower doses are frequently used, but the efficacy and safety of a low-dose regimen of prostaglandin E1 has not been established. METHODS: We investigated neonates with critical CHD who were started on prostaglandin E1 at 0.01 µg/kg/minute. We reviewed 154 consecutive patients who were separated into three anatomical groups: obstruction to systemic circulation, obstruction to pulmonary circulation, and inadequate mixing (d-transposition of the great arteries). Treatment failure rates and two commonly reported side effects, respiratory depression and seizure, were studied. RESULTS: A total of 26 patients (17%) required a dose increase in prostaglandin E1. Patients with pulmonary obstruction were more likely to require higher doses than patients with systemic obstruction (15/49, 31% versus 9/88, 10%, p = 0.003). Twenty-eight per cent of patients developed respiratory depression and 8% of patients needed mechanical ventilation. Prematurity (<37 week gestation) was the primary risk factor for respiratory depression. No patient required dose escalation or tracheal intubation while on transport. No patient had a seizure attributed to prostaglandin E1. CONCLUSIONS: Prostaglandin E1 at an initial and maintenance dose of 0.01 µg/kg/minute was sufficient to maintain ductal patency in 83% of our cohort. The incidence of respiratory depression requiring mechanical ventilation was low and was mostly seen in premature infants. Starting low-dose prostaglandin E1 at 0.01 µg/kg/minute is a safe and effective therapy for critical CHD.

Severe cardiac dysfunction in a patient with multisystem inflammatory syndrome in children associated with COVID-19: Retrospective diagnosis of a puzzling presentation. A case report.

We report one of the earliest known U.S. cases of multisystem inflammatory syndrome in children associated with COVID-19 (MIS-C). This adolescent male presented prior to any known association between COVID-19 and immune mediated inflammatory syndrome in children. He presented in stable condition and without significant multisystem involvement. During hospitalization, he developed severe left ventricular dysfunction and mixed hypovolemic, distributive and cardiogenic shock. Clinical features overlapped with Kawasaki disease, acute rheumatic fever, and toxic shock syndrome. After centers in Europe began reporting a multisystem inflammatory condition in children with COVID-19, the patient's clinical course and laboratory findings were revisited. He underwent newly available antibody testing and was diagnosed as one of the first known cases of MIS-C in the United States.