Pulmonary Flow Management by Combination Therapy of Hemostatic Clipping and Balloon Angioplasty for Right Ventricular-Pulmonary Artery Shunt in Hypoplastic Left Heart Syndrome.

Controlling pulmonary blood flow in patients who have undergone Norwood palliation, especially early postoperatively, is challenging due to a change in the balance of systemic and pulmonary vascular resistance. We applied a combination therapy of clipping and balloon angioplasty for right ventricle-pulmonary artery (RV-PA) shunt to control pulmonary blood flow, but the influence of the combination therapy on the PA condition is uncertain. Retrospectively analysis was conducted of all infants with hypoplastic left heart syndrome who had undergone Norwood palliation with RV-PA shunt at Okayama University Hospital from January 2008 to September 2022. A total of 50 consecutive patients underwent Norwood palliation with RV-PA shunt in this study period. Of them, 29 patients underwent RV-PA shunt flow clipping, and the remaining 21 had unclipped RV-PA shunt. Twenty-three patients underwent balloon angioplasty for RV-PA shunt with clips. After balloon angioplasty, oxygen saturation significantly increased from 69 (59-76)% to 80 (72-86)% (p < 0.001), and the narrowest portion of the clipped conduit significantly improved from 2.8 (1.8-3.4) to 3.8 (2.9-4.6) mm (p < 0.001). In cardiac catheterizations prior to Bidirectional cavo-pulmonary shunt (BCPS), there were no significant differences in pulmonary-to-systemic flow ratio (Qp/Qs), ventricular end-diastolic pressure, Nakata index, arterial saturation, mean pulmonary artery pressure and pulmonary vascular resistance index. On the other hand, in Cardiac catheterizations prior to Fontan, Nakata index was larger in the clipped group (p = 0.02). There was no statistically significant difference in the 5-year survival between the two groups (clipped group 96%, unclipped group 74%, log-rank test: p = 0.13). At least, our combination therapy of clipping and balloon angioplasty for RV-PA shunt did not negatively impact PA growth. Although there is a trend toward better but not statistically significant difference in outcomes in the clipped group compared to the non-clipped group, this treatment strategy may play an important role in improving outcomes in hypoplastic left heart syndrome.

Vascular occlusion with 0.035-inch hydrogel expandable coils in congenital heart diseases and vascular anomalies.

BACKGROUND: We present our experience with transcatheter vascular occlusion using 0.035-inch hydrogel expandable coils, which has been reported only in a few cases in the pediatric cardiology fields. METHODS: This study is a retrospective analysis of all patients who underwent transcatheter embolization with 0.035-inch hydrogel coils at the Department of Pediatrics, Okayama University Hospital, between October 2018 and September 2020. RESULTS: Twenty patients with a median age of 5.1 years (0.05-26.0 years) and a median weight of 13.8 kg (3.0-56.8 kg) were included. A total of fifty-four 0.035-inch hydrogel coils, including 35 Azur 35 and nineteen Azur CX 35 coils (Terumo, Tokyo, Japan), were successfully deployed in 22 target vessels. The target vessels consisted of 10 aortopulmonary collaterals, 8 veno-venous collaterals, and 4 pulmonary arteriovenous malformations. We achieved technical success in all the target vessels. In total, the mean target vessel diameter was 4.4 mm, the mean number of 0.035-inch hydrogel coils was 2.5 per vessel. The mean device to vessel ratio was 1.6 for the anchor coil and 1.2 for the additional coil. Post-implantation angiograms revealed that the primary occlusion rate was 18/22 (82%). There were no periprocedural complications. CONCLUSIONS: The 0.035-inch hydrogel expandable coils are effective and safe in patients with congenital heart disease and vascular anomalies. These occlusion devices could be valuable options for interventional pediatric cardiologists.

Stepwise Treatment for Heterotaxy Syndrome and Functional Single Ventricle Complicated by Infra-Cardiac Total Anomalous Pulmonary Venous Connection with Ductus Venosus Stent Placement and Subsequent Occlusion.

Even today, when the surgical outcome of congenital heart disease in the neonatal period has improved, the prognosis for heterotaxy syndrome and functional single ventricle complicated with total anomalous pulmonary venous connection (TAPVC), especially the infra-cardiac type, is catastrophic. We describe a strategy that combines percutaneous ductus venosus (DV) stent placement and occlusion after TAPVC repair to ensure survival from initial surgery to bidirectional cavopulmonary shunt (BCPS) procedure and facilitate subsequent treatment. Three consecutive patients with heterotaxy syndrome and functional single ventricle complicated by infra-cardiac TAPVC treated with our own strategy were retrospectively studied. In two infants, DV stent placement was performed on the day of birth. In one case at 11 days of age. The risk of pulmonary vein obstruction was reduced, and on-pump surgery, including TAPVC repair, was performed on a standby basis. Since the rapid increase in hepatic enzymes occurred on postoperative day 0 to 1 in all cases, percutaneous stent occlusion was performed until postoperative day 3. The procedure improved liver function. One patient died due to severe atrioventricular valve regurgitation, one case underwent BCPS, and one patient was waiting to undergo. DV stent placement can avoid TAPVC repair in the early neonatal period. After TAPVC repair, the portosystemic shunt remained, resulting in hepatic dysfunction, but this could be improved by stent and vertical vein occlusion. A series of stepwise treatments can be useful to help such critically ill infants survive the high-risk neonatal period and achieve good BCPS circulation.

Cardiosphere-derived exosomal microRNAs for myocardial repair in pediatric dilated cardiomyopathy.

Although cardiosphere-derived cells (CDCs) improve cardiac function and outcomes in patients with single ventricle physiology, little is known about their safety and therapeutic benefit in children with dilated cardiomyopathy (DCM). We aimed to determine the safety and efficacy of CDCs in a porcine model of DCM and translate the preclinical results into this patient population. A swine model of DCM using intracoronary injection of microspheres created cardiac dysfunction. Forty pigs were randomized as preclinical validation of the delivery method and CDC doses, and CDC-secreted exosome (CDCex)-mediated cardiac repair was analyzed. A phase 1 safety cohort enrolled five pediatric patients with DCM and reduced ejection fraction to receive CDC infusion. The primary endpoint was to assess safety, and the secondary outcome measure was change in cardiac function. Improved cardiac function and reduced myocardial fibrosis were noted in animals treated with CDCs compared with placebo. These functional benefits were mediated via CDCex that were highly enriched with proangiogenic and cardioprotective microRNAs (miRNAs), whereas isolated CDCex did not recapitulate these reparative effects. One-year follow-up of safety lead-in stage was completed with favorable profile and preliminary efficacy outcomes. Increased CDCex-derived miR-146a-5p expression was associated with the reduction in myocardial fibrosis via suppression of proinflammatory cytokines and transcripts. Collectively, intracoronary CDC administration is safe and improves cardiac function through CDCex in a porcine model of DCM. The safety lead-in results in patients provide a translational framework for further studies of randomized trials and CDCex-derived miRNAs as potential paracrine mediators underlying this therapeutic strategy.

Balloon atrial septostomy in hypoplastic left heart syndrome with restrictive atrial septum.

BACKGROUND: Rashkind balloon atrial septostomy (BAS) can be challenging in infants with hypoplastic left heart syndrome (HLHS) and small atrial septal defect (ASD). METHODS: We retrospectively reviewed all infants with HLHS who underwent surgery and BAS between January 2006 and December 2015. The infants were divided into three groups: no BAS; catheter BAS; and open AS. Infants who underwent catheter BAS were divided into two groups based on atrial septal anatomy: standard and complex. RESULTS: Of the 70 patients, 57 (81%) underwent Glenn surgery. Subsequently, a significant difference in survival was observed: 86% (44/51), 91% (10/11), and 25% (2/8) in the no BAS, catheter BAS, and open AS groups, respectively (P = 0.0002). No significant difference was seen between the no BAS and the catheter BAS groups (P = 1.0). In the 56 patients who underwent catheterization after surgery, no intergroup differences in mean pulmonary artery pressure, pulmonary vascular resistance, or pulmonary artery index were found. We classified catheter BAS into standard (n = 5) and complex (n = 5) based on ASD location, and septum thickness. All patients in the standard group underwent complete Rashkind BAS, but in the complex group, only one patient underwent complete Rashkind BAS, with the remaining requiring initial static BAS (P = 0.048). Following septostomy, ASD size, ASD flow, and percutaneous oxygen saturation (SpO2 ) were not significantly different between the two groups. CONCLUSIONS: Catheter BAS is effective in infants with HLHS and a restrictive atrial septum. Infants with standard or complex atrial septum can achieve equivalent outcomes despite more patients often requiring static BAS.

Changes in the features of invasive pneumococcal disease after introduction of the seven-valent pneumococcal conjugate vaccine in a regional core hospital of Kochi, Japan.

Since the introduction of the seven-valent pneumococcal conjugate vaccine (PCV7) in 2007, invasive pneumococcal disease has declined, but the incidence of Streptococcus pneumoniae serotype 19A has risen worldwide. The present study examined changes in the features of invasive pneumococcal disease since the introduction of the PCV7 in Kochi, Japan. Pediatric cases of invasive pneumococcal disease were investigated before and after vaccine introduction (January 2008 to December 2013). Cases of invasive pneumococcal disease tended to decrease after PCV7 introduction. In addition, before introduction of the vaccine, most serotypes causing invasive pneumococcal disease were those included in the vaccine. However, after the introduction, we found cases infected by serotypes not covered by vaccine. Penicillin-resistant S. pneumoniae was the predominant serotype causing invasive pneumococcal disease before introduction of the PCV7, and the susceptibility of this serotype to antibiotics improved after vaccine introduction. Serotype isolates identified after vaccine introduction were also relatively susceptible to antibiotic therapy, but decreased susceptibility is expected.

Ventriculoperitoneal shunt outcomes among infants.

Ventriculoperitoneal shunts (VPSs) are used for the treatment of hydrocephalus. Here we analyzed the outcomes of VPS placements in 24 infants to determine the risk factors for shunt failure. The infants had undergone the initial VPS operation in our hospital between March 2005 and December 2013. They were observed until the end of January 2014. We obtained Kaplan-Meier curves and performed a multivariate Cox regression analysis of shunt failure. Of the 24 cases, the median (range) values for gestational age, birth weight, and birth head circumference (HC) were 37 (27-39) wks, 2,736 (686-3,788) g, and 35.3 (23.0-45.3) cm, respectively. The total number of shunt procedures was 45. Shunt failure rates were 0.51/shunt and 0.0053/shunt/year. Shunt infection rates were 0.13/shunt and 0.0014/shunt/year. The Kaplan-Meier analysis revealed an increased risk for shunt failure in infants <1 month old or in the HC >90%tile. The Cox regression analysis yielded hazard ratios (HRs) of 2.93(95% confidence interval (CI), 0.96-10.95, p=0.059) for age <1 month, and 4.46 (95%CI:1.20-28.91, p=0.023) for the HC >90%tile. The multivariate Cox regression analysis showed adjusted HRs of 17.56 (95%CI:2.69-202.8, p=0.001) for age <1 month, and 2.95 (95%CI:0.52-24.84, p=0.228) for the HC >90%tile. Our findings thus revealed that the risk factors for shunt failure in infants include age <1 month at the initial VPS placement.

Seeding of mesenchymal stem cells into inner part of interconnected porous biodegradable scaffold by a new method with a filter paper.

An appropriate physical support provided by scaffolds creates a supportive environment that directs proliferation and differentiation of stem cells. However, it is difficult to homogenously inoculate stem cells into the inner part of scaffolds at high cell densities. In this study, mesenchymal stem cells were seeded into a hydroxyapatite/poly (D, L-lactic-co-glycolic acid) (HAP/PLGA) scaffold that had enough mechanical strength and porous 3-D structure. With an aid of a filter paper placed under the bottom of a HAP/PLGA block, the cells suspended in a culture medium flowed from the top to the bottom through interconnected pores in the scaffold, and distributed almost homogenously, as compared to cell distribution near the surface of the block by the conventional method using centrifugation or reduced pressure. This simple method with a filter paper may be useful in preparation of cell-scaffold complexes for tissue engineering.