YIA-2 Does reversal of flow in the fetal aortic arch in second trimester aortic stenosis predict hypoplastic left heart syndrome? Introduction: Although the treatment of intravenous immunoglobulin (IVIG) significantly resolves inflammation, 10-20% of Kawasaki disease (KD) patients have persistent or recurrent fever after the administration of IVIG, and IVIG-resistant patients have a particularly high risk of developing coronary artery abnormalities. The mechanisms of IVIG-resistant KD have been

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... analyzed using the patients' leukocyte samples. However, vascular endothelial cells (ECs), closely related to the vasculitis of KD, have not been examined in the previous reports. We propose a hypothesis that ECs are mainly involved in the etiology of IVIG-resistance. Methods: The purpose of this study is to establish new in vitro disease models of vasculitis using induced pluripotent stem cell (iPSC) technology, and clarify the mechanisms of IVIG-resistance in KD. Dermal fibroblasts or T cells from 2 IVIG-resistant and 2 IVIG-responsive KD patients were reprogrammed by episomal vectors encoding Oct3/4, Sox2, Klf4, L-Myc, LIN28, and p53 shRNA. The iPSC lines were then differentiated into ECs and smooth muscle cells (SMCs) by using a previously-reported differentiation method, and the EC and SMC samples were subjected to the microarray analyses. Results: The KD patient-derived iPSCs could be differentiated into ECs and SMCs. The gene expression profiles were compared between iPS-derived ECs (iPS-ECs) generated from IVIG-resistant and IVIGresponsive KD patients, and between iPS-derived SMCs (iPS-SMCs) generated from two group patients. We found the expression of chemokine X, which stimulates migration of monocytes and T-lymphocytes through its receptors, was significantly up-regulated both in iPS-ECs and in iPS-SMCs from IVIG-resistant KD patients compared with those from IVIG-responsive patients. The Principle Component Analysis (PCA) was performed, but the gene expression levels showed no significant differences between the groups. The Gene Set Enrichment Analysis (GSEA) revealed that the gene sets related to IL-6, NRAS (a member of the RAS oncogene family) and breast cancer were up-regulated in iPS-ECs from IVIG-resistant KD patients. Conclusions: Taking into account that the concentration of IL-6 has been reported to be elevated in acute phase of IVIG-resistant KD, our results suggest that the up-regulation of IL-6 related genes in ECs might be involved in the pathogenesis of IVIG-resistant KD. YIA-4 Improvement of haemodynamic flow abnormalities after aortic valve replacement in bicuspid aortic valve disease Bissell M.M., Loudon M., Stoll V., Knight S.P., Orchard E., Neubauer S., Myerson S.G. Introduction: Bicuspid aortic valve disease (BAV) is associated with dilatation of the proximal aorta and abnormal flow patterns, particularly increased helical flow and changes in the aortic wall shear stress. The aortic dilation may be slowed by aortic valve replacement via normalisation of flow patterns. We assess the effect of different types of aortic valve replacement (AVR) on aortic flow patterns. Methods: We prospectively enrolled 69 participants: 23 BAV patients with prior AVR (10 mechanical, 6 bioprosthetic, 7 Ross procedure), 23 BAV patients with a native aortic valve and 23 healthy volunteers. All underwent 4D flow cardiovascular magnetic resonance. Results: The majority of patients with mechanical AVR or Ross showed a normalised flow pattern (70% and 57% respectively) with near normal rotational flow values (7.4 ± 3.9 and 11.0 ± 12.0 mm2/s respectively; normal range −5 to +11 mm2/s); and reduced in-plane wall shear stress compared to native BAV (0.13 ± 0.18 N/m2 for mechanical AVR vs. 0.37 ± 0.26 N/m2 for native BAV, p < 0.05). In contrast, all subjects with bioprosthetic AVR showed abnormal flow patterns (mainly marked right-handed helical flow), with similar S2 Cardiology in the Young: Volume 25 Supplement 1 https://www.cambridge.org/core/terms. https://doi. Objective: Management for pregnant female patients of Kawasaki disease (KD) with severe coronary arterial lesions (CAL) is recently closed up. Pregnancy is thought to have two problems to maintain antiplatelet effect. One is acceleration of coagulation, and the other is increased heparin clearance. Those problems are more serious for KD patients with CAL. The feasibility of continuous intravenous heparin administration (CIVH) for them is necessary to be evaluated. Method: We experienced 6 deliveries in 4 patients who switched oral aspirin to CIVH of 5-8 unit/kg/hour before delivery. Conferences with cardiologists, obstetricians and pediatricians including neonatologists were done for each case before and/or after their admission. Those medical records were summarized retrospectively. Results: Age of expecting female KD patients was 28.5 years in average. All patients had left CAL and two had right CAL also. Three of them had ischemic finding by scintigraphy and coronary CT angiogram before pregnancy. No patient was prescribed warfarin. Three of them were prescribed aspirin, but one of them and the other patient were lost to follow-up of our university hospital. They came back to follow-up at our hospital after they were aware of pregnancy. They admitted to our hospital 7 to 14 days before expected date, and spontaneous, vaginal delivery was indicated in 4 deliveries. In two cases decided to carry out Caesarian section at 38th gestational week. All patients discontinued aspirin after admission and at latest 7 days before delivery and started CIVH and restarted aspirin from 24 to 48 hours after deliver. In all cases, target of activated partial thromboplastin time (APTT) was controlled over 50 seconds. All 6 deliveries completed and newborns were all mature with no hemorrhagic complication. No KD patients developed any hemorrhagic or thrombotic complication. Discussion: APTT control longer than 50 seconds by CIVH is enough to warrant prevention of thrombotic event. Safe upper limit of APTT control without bleeding complication and the pros and cons of pregnancy in KD patients treated with warfarin are still two assignments. Team approaching should be achieved for appropriate management of the expecting patients with CAL after KD. YIA-6 Outcomes after Protein-Losing Enteropathy in Univentricular Hearts: a Multicenter Study