Andrew C. Glatz

BACKGROUND: Plastic bronchitis is a potentially fatal disorder occurring in children with single-ventricle physiology, and other diseases, as well, such as asthma. In this study, we report findings of abnormal pulmonary lymphatic flow, demonstrated by MRI lymphatic imaging, in patients with plastic bronchitis and percutaneous lymphatic intervention as a treatment for these patients. METHODS AND RESULTS: This is a retrospective case series of 18 patients with surgically corrected congenital heart disease and plastic bronchitis who presented for lymphatic imaging and intervention. Lymphatic imaging included heavy T2-weighted MRI and dynamic contrast-enhanced magnetic resonance lymphangiogram. All patients underwent bilateral intranodal lymphangiogram, and most patients underwent percutaneous lymphatic intervention. In 16 of 18 patients, MRI or lymphangiogram or both demonstrated retrograde lymphatic flow from the thoracic duct toward lung parenchyma. Intranodal lymphangiogram and thoracic duct catheterization was successful in all patients. Seventeen of 18 patients underwent either lymphatic embolization procedures or thoracic duct stenting with covered stents to exclude retrograde flow into the lungs. One of the 2 patients who did not have retrograde lymphatic flow did not undergo a lymphatic interventional procedure. A total of 15 of 17(88%) patients who underwent an intervention had significant symptomatic improvement at a median follow-up of 315 days (range, 45-770 days). The most common complication observed was nonspecific transient abdominal pain and transient hypotension. CONCLUSIONS: In this study, we demonstrated abnormal pulmonary lymphatic perfusion in most patients with plastic bronchitis. Interruption of the lymphatic flow resulted in significant improvement of symptoms in these patients and, in some cases, at least temporary resolution of cast formation.

Background Congestive hepatopathy is a recognized complication of Fontan physiology. Data regarding the incidence of hepatopathy and risk factors are lacking. Methods and Results Liver biopsies and cardiac catherizations were performed as part of an evaluation offered to all patients ≥10 years after Fontan. Quantitative determination of hepatic fibrosis was performed using Sirius red staining with automated calculation of collagen deposition per slide (% CD ). Biopsies from included subjects were compared to stained specimens from controls without known fibrotic liver disease. Patient characteristics, echocardiographic findings, and hemodynamic measures were evaluated as potential risk factors. The cohort consisted of 67 patients (31 female) at mean age of 17.3±4.5 years and mean time from Fontan of 14.9±4.5 years. Right ventricular morphology was present in 37 subjects. Median % CD by Sirius red staining was 21.6% (range 8.7% to 49.4%) compared to 2.6% (range 2.2% to 3.0%) in controls. There was a significant correlation between time from Fontan and degree of Sirius red staining ( r =0.33, P <0.01). Serum liver enzymes and platelet count did not correlate with % CD . The median inferior vena cava pressure was 13 mm Hg (range 6‐24 mm Hg) and did not correlate with % CD . There was no difference in % CD based on ventricular morphology or severity of atrioventricular valve insufficiency. Conclusions In this cohort of predominantly asymptomatic children and adolescents electively evaluated after a Fontan operation, all exhibited evidence for hepatic fibrosis as measured by collagen deposition in the liver. Time from Fontan was the only factor significantly associated with collagen deposition. These findings demonstrate that liver fibrosis is an inherent feature of Fontan physiology and that the degree of fibrosis increases over time.

Background: Infants with ductal-dependent pulmonary blood flow may undergo palliation with either a patent ductus arteriosus (PDA) stent or a modified Blalock-Taussig (BT) shunt. A balanced multicenter comparison of these 2 approaches is lacking. Methods: Infants with ductal-dependent pulmonary blood flow palliated with either a PDA stent or a BT shunt from January 2008 to November 2015 were reviewed from the 4 member centers of the Congenital Catheterization Research Collaborative. Outcomes were compared by use of propensity score adjustment to account for baseline differences between groups. Results: One hundred six patients with a PDA stent and 251 patients with a BT shunt were included. The groups differed in underlying anatomy (expected 2-ventricle circulation in 60% of PDA stents versus 45% of BT shunts; P =0.001) and presence of antegrade pulmonary blood flow (61% of PDA stents versus 38% of BT shunts; P <0.001). After propensity score adjustment, there was no difference in the hazard of the primary composite outcome of death or unplanned reintervention to treat cyanosis (hazard ratio, 0.8; 95% confidence interval [CI], 0.52–1.23; P =0.31). Other reinterventions were more common in the PDA stent group (hazard ratio, 29.8; 95% CI, 9.8–91.1; P <0.001). However, the PDA stent group had a lower adjusted intensive care unit length of stay (5.3 days [95% CI, 4.2–6.7] versus 9.19 days [95% CI, 7.9–10.6]; P <0.001), a lower risk of diuretic use at discharge (odds ratio, 0.4; 95% CI, 0.25–0.64; P <0.001) and procedural complications (odds ratio, 0.4; 95% CI, 0.2–0.77; P =0.006), and larger (152 mm 2 /m 2 [95% CI, 132–176] versus 125 mm 2 /m 2 [95% CI, 113–138]; P =0.029) and more symmetrical (symmetry index, 0.84 [95% CI, 0.8–0.89] versus 0.77 [95% CI, 0.75–0.8]; P =0.008] pulmonary arteries at the time of subsequent surgical repair or last follow-up. Conclusions: In this multicenter comparison of palliative PDA stent and BT shunt for infants with ductal-dependent pulmonary blood flow adjusted for differences in patient factors, there was no difference in the primary end point, death or unplanned reintervention to treat cyanosis. However, other markers of morbidity and pulmonary artery size favored the PDA stent group, supporting PDA stent as a reasonable alternative to BT shunt in select patients.