BACKGROUND: Pediatric intraluminal pulmonary vein stenosis (PVS) occurs in a heterogeneous patient population but is unified by its cellular composition in affected pulmonary veins. Enhanced delineation of the hemodynamic and physiological vein consequences of PVS and its impact on vein lumen, vein pressure, wall structure, vein compliance, and wall shear stress has not been studied. The objective is to assess PVS characteristics using multimodal catheterization techniques (angiography, pulmonary vein pressure, intravascular ultrasound, balloon compliance testing, and wall shear stress calculation) and determine their association with vein outcomes. METHODS: Prospective trial (URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04696289) applying a standardized catheterization assessment to patients under 13 years of age who are undergoing cardiac catheterization for PVS. The primary outcome is vein status at 12 months, assigned by an end point committee. The secondary outcome is transplant-free survival. RESULTS: Overall, 50 patients with a median age of 2.7 years (range, 0.3–11.8) underwent assessment and included angiography of 200 veins, 171 pressure assessment, 169 intravascular ultrasound, 58 balloon compliance testing, and 141 wall shear stress calculations. The probability of a worse vein outcome increased as angiographic severity score, percent wall thickness by intravascular ultrasound, postintervention gradient, or postintervention wall shear stress increased. Multivariable analysis demonstrated veins with angiographic upstream luminal narrowing (odds ratio, 3.26 [95% CI, 1.38–7.7]; P =0.007), ostial diameter <6 mm (odds ratio, 3.93 [95% CI, 1.29–12]; P =0.016), and ≥35% upstream wall thickness by intravascular ultrasound (odds ratio, 5.05 [95% CI, 2.03–12.5]; P <0.001) are associated with a worse vein outcome. A 3-point Invasive Pulmonary Vein Score prediction tool was created. Transplant-free survival was 92% at 12 months. CONCLUSIONS: A multimodal pulmonary vein catheterization assessment determined angiographic and intravascular ultrasound findings to be the most predictive of 12-month pulmonary vein outcome.

Pulmonary vein stenosis results from a proliferative process that leads to the progressive obstruction of venous return to the left atrium. It is often resistant to catheterization and surgical based interventions and is frequently fatal when encountered in its severe form. Here, we describe three patients with severe, primary pulmonary vein stenosis that was progressing despite aggressive conventional management strategies. All three patients were initiated on combination chemotherapy with imatinib and sirolimus, drugs which have been previously shown to independently have potential benefit against PVS. Soon after the initiation of these therapies, all three patients experienced a stabilization of their disease process and clinical improvement. All three patients remain alive, with tolerable side effects from the medications. Although early in our experience and with only a small number of patients, combination chemotherapy with imatinib and sirolimus shows promise and merits further investigation as a therapeutic option for this aggressive disease.

Background/Objectives: Premature infants are often referred for the definitive procedural closure of the patent ductus arteriosus (PDA) with the failure of, or contraindication to, pharmacotherapy and the inability to wean respiratory support. However, once this need is identified, the importance of expedited closure is unclear. The objective of this study was to compare the effect of the timing of definitive closure (i.e., surgical ligation or device occlusion) on early respiratory outcomes in premature infants. Method: We first specify a hypothetical randomized trial (the “target trial”) that would estimate the effect on extubation of early (0–4 days from referral) vs. late (5–14 days from referral) definitive PDA closure. We then emulate this target trial using a single-institution registry of premature infants (born <30 weeks or with a birth weight < 1500 g) who underwent the definitive closure of PDA between January 2014 and October 2023. Results: We identify 131 eligible infants. At the end of the follow-up, 70 and 38 infants were adherent to early and late PDA closure strategies, respectively. The cumulative incidence of extubation in the early group was higher than that in the late group until day 40 (maximum risk difference: 22 percentage points at day 13; 95% CI: −11 to 56). Outcomes were similar at the end of the 45-day follow-up period (risk difference: −1 percentage point; 95% CI: −46 to 42). Conclusions: The need for mechanical ventilation was equivalent between early and late PDA closure strategies at the end of a 45-day follow-up period although infants in the early intervention group were extubated sooner.

(1) Background: To identify reasons for the persistence of surgical ligation of the patent ductus arteriosus (PDA) in premature infants after the 2019 Food and Drug Administration (FDA) approval of transcatheter device closure; (2) Methods: We performed a 10-year (2014–2023) single-institution retrospective study of premature infants (<37 weeks) and compared clinical characteristics and neonatal morbidities between neonates that underwent surgical ligation before (epoch 1) and after (epoch 2) FDA approval of transcatheter closure; (3) Results: We identified 120 premature infants that underwent surgical ligation (n = 94 before, n = 26 after FDA approval). Unfavorable PDA morphology, active infection, and recent abdominal pathology were the most common reasons for surgical ligation over device occlusion in epoch 2. There were no differences in demographics, age at closure, or outcomes between infants who received surgical ligation in the two epochs; (4) Conclusions: Despite increasing trends for transcatheter PDA closure in premature infants, surgical ligation persists due to unfavorable ductal morphology, active infection, or abdominal pathology.

Background: Diastolic dysfunction is a major driver of morbidity in congenital heart disease (CHD), but its mechanisms are poorly understood. It remains unknown whether left ventricular (LV) diastolic dysfunction in borderline left heart patients is caused by a defect in active relaxation or in passive compliance. Objectives: We sought to apply gold-standard pressure-volume (PV) loop analysis to define the primary mechanism of diastolic dysfunction in patients with borderline LV (bLV). Methods: We analyzed invasive PV loop data from pediatric patients with bLV (n =13) and a comparison group of patients with congenitally corrected transposition of the great arteries (ccTGA, presumed no diastolic dysfunction; n=14). PV loops were generated during transient preload reduction and augmentation. Active relaxation was assessed by the isovolumic relaxation time-constant (?) and maximal rate of pressure decline (dP/dtmin) indexed to peak-systolic pressure (PSP). Passive compliance was quantified by the chamber stiffness constant (?), derived from the multi-beat end-diastolic PV relationship (EDPVR). To account for size differences, ? was (1) calculated using indexed ventricular volumes (i?), and (2) converted to a dimensionless stiffness constant (?W) by multiplying ? by ventricular wall volume. Results: Active relaxation measures were similar between groups, indicating normal lusitropy in bLV (? bLV: 28 [23.5-29.5] vs ccTGA: 24 [21-28] msec, p=0.10; dP/dtmin/PSP bLV: -10.6 [-11.0, -9.4] vs. ccTGA: -9.9 [-10.5, -8.7] s-1, p=0.17). In contrast, patients with bLV had markedly abnormal passive compliance. The EDPVR was shifted sharply upward and to the left, and the stiffness constants were significantly higher in the bLV group (i? bLV: 0.10 [0.04-0.35] vs. ccTGA: 0.03 [0.02-0.04] m2/mL, p=0.003); ?W bLV: 4.08 [1.60-7.52] vs. ccTGA: 1.21 [0.95-1.77], p=0.002). Conclusions: The primary mechanism of diastolic dysfunction in bLV is impaired passive ventricular compliance, and not impaired active relaxation. These findings suggest a limited role for lusitropic medications and therapeutic strategies that focus on mitigating ventricular stiffness (such as surgical endocardial fibroelastosis resection) may be more valuable.

Introduction: Originally introduced in Health Affairs in 2013, Standardized Clinical Assessment and Management Plans (SCAMPs) are clinician-developed, modifiable care pathways designed to reduce unwarranted variation and optimize resource use while preserving professional judgment. Unlike traditional clinical practice guidelines that prescribe “best” practice, SCAMPs begin with consensus-based “sound” practice and emphasize iterative learning from real-world deviations and outcomes. Initially developed for conditions with limited evidence, SCAMPs have since expanded across a wide range of diagnoses and care settings. Methods: We conducted a structured historical review of more than 40 peer-reviewed publications describing SCAMPs development, implementation, evaluation, and iterative refinement. The review synthesizes reported experiences across clinical domains, settings, and study designs, and is intended as a descriptive, perspective-oriented assessment rather than a formal systematic review. Results: Published SCAMPs reports describe broad deployment across diverse conditions and institutions, with recurrent findings of reduced practice variation, changes in resource utilization, iterative pathway refinement, and high reported adherence among participating clinicians. The literature also reflects important limitations, including heterogeneity of study designs, limited evaluation of harms, equity, patient-reported outcomes, and implementation burden, and likely underrepresentation of unsuccessful implementations. Early reliance on paper-based workflows constrained scalability and consistency of use. Conclusion: This perspective synthesizes the published SCAMPs experience, highlighting reported benefits alongside implementation conditions, risks, and limitations. SCAMPs are best understood as a clinician-led methodology whose value is conditional on governance, analytic capacity, patient safety oversight, and attention to equity. Emerging informatics standards and artificial intelligence tools may enhance scalability and learning, but require careful governance to avoid amplifying bias or harm.