Repair of iatrogenic left pulmonary artery to left atrial appendage fistula using a covered CP stent: a case report.

We report a case of iatrogenic left pulmonary artery-left atrial appendage fistula following percutaneous transluminal angioplasty for residual pulmonary artery stenosis in an 11-year-old boy. This rare complication could have been predicted by understanding the anatomical relationship of these structures. In this study, simulation using three-dimensional printing greatly contributed to successful stent placement.

Epidemiologic study of patients after Fontan operation based on Medical Aid Program for Chronic Pediatric Diseases of Specified Categories cohort.

Nationwide registry data of patients with single-ventricle physiology have been rarely reported. The Medical Aid Program for Chronic Pediatric Diseases of Specified Categories (Japan) has contributed to the financial support of medical expense for patients younger than 20 years with chronic paediatric disease, and almost all children in Japan who require disease-specific treatment voluntarily apply to this programme. The epidemiology and medium- to long-term outcome of patients following a Fontan procedure were investigated using the database. The usefulness of this epidemiologic investigation in identifying real-world objectives and clinical applications was also examined. A total of 2862 patients who underwent a Fontan operation were identified from 18,589 patients with chronic heart disease registered to the medical aid programme. The details of symptoms, treatment, and somatic growth were evaluated, from which we were able to clarify the nationwide data regarding the current status of post-Fontan patients younger than 20 years. This study elucidated the current status of post-Fontan patients under 20 years of age in Japan. Data analysis of the Medical Aid Program for Chronic Pediatric Diseases of Specified Categories cohort provided useful information towards understanding the comprehensive status of patients with chronic heart disease and contributed to improved disease management.

Transcatheter retrieval of atrial septal defect and patent ductus arteriosus occluder: a guidance for device retrieval based on comprehensive bench tests.

OBJECTIVES: The aim of this study is to establish a guidance for device retrieval based on comprehensive bench tests. BACKGROUND: Device embolisation remains a major complication in transcatheter closure of atrial septal defect and patent ductus arteriosus. Although percutaneous retrieval is feasible in the majority of cases, surgical retrieval may be required in complicated circumstances. However, the methods of transcatheter device retrieval have not been completely established. METHODS: Bench tests of device retrieval were performed to verify the appropriate retrieval method according to device type/size. The devices used for testing were Amplatzer Septal Occluder (Abbott, Chicago, IL, United States of America), Figulla Flex II (Occlutech GmbH, Jena, Germany), Amplatzer Duct Occluder-I (Abbott), Amplatzer Duct Occluder-II (Abbott), and Amplatzer Vascular Plug-II (Abbott). The retrieval equipment constituted diagnostic catheters (multipurpose catheter and right Judkins catheter, 4-Fr or 5-Fr, Gadelius Medical, Tokyo, Japan), delivery sheath and cables for each device, Amplatz goose neck snares (Medtronic, Minneapolis, MN, United States of America), OSYPKA CATCHER (Osypka ag, Rheinfelden-Herten, Germany), and OSYPKA LASSOS (Osypka). We investigated the retrieval equipment and sheath sizes required for a successful retrieval procedure for variously sized devices. RESULTS: For patent ductus arteriosus devices, the type of snare and the snaring position are considered important. For atrial septal defect devices, simple snare capture or a double-snare technique with a sufficiently large sheath is effective. Special care should be taken when using the OSYPKA CATCHER for device retrieval. CONCLUSIONS: The results of this study may assist in the selection of both capture devices and a retrieval sheath or a catheter for complete retrieval.

Practice and Safety of Static Balloon Atrial Septostomy Based on a Nationwide Registry Data.

BACKGROUND: Balloon atrial septostomy (BAS) is an essential catheterization procedure for congenital heart lesions. Recently, a balloon catheter for static BAS was approved for the first time in Japan as an alternative to the conventional pull-through BAS. Despite the expected increase in the use of static BAS, reports on its safety are scarce worldwide.Methods and Results: Data on static and pull-through BAS registered in a national registry between 2016 and 2018 were collected. During the study period, 247 sessions of static BAS and 588 sessions of pull-through BAS were performed on a total of 674 patients. Patients who underwent static BAS were older (P<0.001). The incidence of serious adverse events (4.3% vs. 0.9%, P=0.03) and the overall incidence of adverse events (8.1% vs. 3.2%, P=0.03) were higher in static BAS than in pull-through BAS. Among patients who underwent static BAS, the risk factor for adverse events was a body weight <3 kg at the time of the procedure (odds ratio: 4.3 [confidence interval: 1.7-11], P=0.003). CONCLUSIONS: This nationwide study revealed differences in patient background between static and pull-through BAS, as well as a higher incidence of adverse events related to static BAS. Patients weighing <3 kg are at high risk for adverse events after static BAS and may require surgical and circulatory support backup.

Birth Weight Standard Deviation Score is a Significant Determinant of Serum Urotensin-II Levels at Term-Equivalent Age in Preterm Infants.

OBJECTIVE: Urotensin II (U-II) is a potent vasoconstrictor peptide, and increased U-II levels are associated with atherosclerosis and hypertension in adults. Low birth weight (LBW) infants have higher risks of such diseases in the future. A small number of nephrons is one of possible mechanism underlying these risks in LBW infants, while vascular elasticity and cardiac function might be another important factor. The objective of this study is to evaluate U-II levels in preterm LBW infants at an early stage of life and determine perinatal factors associated with U-II levels. STUDY DESIGN: The study population consisted of 57 preterm LBW infants (26 males and 31 females), including 49 appropriate for gestational age (AGA) and 8 small for gestational age (SGA) infants, born at a gestational age of ≤34 weeks with a mean birth weight of 1,589 g. Serum U-II levels were measured at term-equivalent age to evaluate perinatal factors related to serum U-II levels. RESULTS: Preterm SGA infants had significantly higher serum U-II levels than preterm AGA infants at term-equivalent age (p = 0.019). Serum U-II levels in preterm LBW infants at term-equivalent age were inversely correlated with birth weight standard deviation (SD) score in a simple regression analysis (r = - 0.395, p = 0,002) and the correlation was maintained in the multiple regression analysis. CONCLUSION: Our results indicate that birth weight SD score might be associated with serum U-II levels in preterm LBW infants at term-equivalent age. Further studies are required to determine whether U-II levels at an early stage of life might influence the risk of atherosclerosis and hypertension. KEY POINTS: · U-II is a potent vasoconstrictor.. · We evaluated serum U-II levels in preterm infants.. · Fetal growth is negatively related to serum U-II levels..

"Half-uncovered technique" to secure larger stents for postoperative pulmonary vein stenosis.

Although larger stent placement could be effective for pulmonary vein stenosis, stents extrusion tends to occur due to caliber narrowing, small landing area, and the slippery nature. We placed stents with diameter ≧8 mm for four stenotic lesions using the "half-uncovered technique". All stents were precisely placed and successfully resolved the stenosis. This technique allows us to avoid extrusion and to perform safe and effective dilatation when placing larger stents for pulmonary vein stenosis.

Stent Implantation for Congenital Heart Diseases in Japan　- Comprehensive Analysis From the Japanese Society of Congenital Interventional Cardiology Registry.

BACKGROUND: Stent implantation for vascular stenosis associated with congenital heart diseases is commonly performed as an off-label procedure in Japan because there is no officially approved stent for any congenital heart disease.Methods and Results:We analyzed data from the Japanese Society of Congenital Interventional Cardiology Registry collected from January 2016 to December 2018. Patients who underwent stent implantation were enrolled in the present analysis. During the study period, there were 470 procedures, 443 sessions, and 391 cases. Of 443 sessions, 427 (96.4%) succeeded procedurally. There were no differences in the procedural success rates among age groups. In all, 416 sessions (367 patients; 94%) resulted in survival to 30 days after catheter intervention. Of 392 admissions, 357 patients (91%) survived to discharge. Only 4 deaths were directly related to stent implantation. Some in-hospital complications were observed during 55 of 443 sessions. Both hospital deaths and serious complications were significantly more frequent in the group with various preoperative risk factors. CONCLUSIONS: Although not officially approved for congenital heart diseases in Japan, stent implantation in congenital heart diseases has been widely and routinely performed for many years with safety and efficacy. The aim of stenting was variable and broad because of many different applications and morphological variations. These data may facilitate approval of such an important device in Japan.

Clinical trial of the CP stent for pulmonary artery stenosis: the first investigator-initiated clinical trial for pediatric interventional cardiology in Japan.

Stenting is an important treatment option for pulmonary artery stenosis (PS) associated with congenital heart disease (CHD). However, no stent has been approved for this indication in Japan, despite negotiation between academia and the regulatory bodies for longer than 20 years. To evaluate efficacy and safety of the CP stent, we performed the first investigator-initiated clinical trial for pediatric interventional cardiology in Japan. This trial was designed as a single-arm, prospective, clinical trial. Patients who had postoperative PS associated with CHD were included. Stenting was attempted in 24 cases and succeeded in 22 cases. The median age of the patients was 11 years (3-36 years) and weight was 38 kg (12-69 kg), while follow-up for 12 months was completed. In all 22 cases, stenting was successful, with a 50% increase in the minimum lumen diameter (MLD) in 86.4% of patients (90% confidence interval, 68.4-96.2%). The mean percent change in MLD was 119.3 ± 52.5%. In two-ventricle repair, the mean percent change in systolic right ventricular/aortic pressure was - 8.5 ± 16.1%, while that of pressure gradient was - 55.9 ± 41.7%. In single-ventricle repair, the percent change in the mean pressure gradient was - 100.0 ± 0%, while that of SaO2 was 1.4 ± 1.7%. No serious adverse events or significant restenosis was reported. The CP stent is highly effective and safe for PS associated with CHD. This study has significant importance in not only scientific but also social considerations.

Use of the novel curved GOKU balloon catheter for acute-angled lesions in palliative surgery for congenital heart disease: comparison with a conventional straight balloon.

Obstruction develops commonly at the acute-angled portion of the vessels following palliative surgery, such as systemic-pulmonary shunt (SP shunt), right ventricle-to-pulmonary artery shunt (RV-PA shunt) in the Norwood-Sano procedure for hypoplastic left heart syndrome, and cavopulmonary (Glenn) anastomosis. Although balloon angioplasty is a treatment option, dilation with existing straight balloons is sometimes ineffective and technically complicated because of balloon slippage and target vessel distortion. In this study, we investigated the effectiveness of a curved GOKU balloon catheter for balloon angioplasty in postoperative acute-angled lesions associated with palliative surgery for congenital heart disease. We reviewed patients who underwent balloon angioplasty for angled lesions complicated by SP shunt, RV-PA shunt, or Glenn anastomosis, using the novel curved GOKU or a conventional balloon catheter, such as a Sterling balloon catheter. We evaluated patients' backgrounds, balloon specifications, target lesion anatomical features and angles, and short-term outcomes. We evaluated 45 procedures in 18 patients. A curved GOKU was used in 20 procedures, and a Sterling balloon in 25 procedures. The angulation of the lesions at maximum balloon inflation was significantly smaller using a curved GOKU vs a Sterling balloon [70-120 (mean ± standard deviation, 97 ± 40) degrees vs 110-180 (149 ± 46) degrees, respectively; p < 0.001], while the original angle was similar between the groups. Patients' short-term outcomes with the curved GOKU were excellent, with a significantly better percent increase in minimum lumen diameter of 0-220% (92% ± 66%) vs 0-46% (18% ± 15%) with the Sterling balloon (p < 00.1) and with less frequent balloon slippage. The curved GOKU was more effective in balloon angioplasty for acute-angled lesions compared with a conventional straight balloon, likely because of better conformability to the lesion angle and slip resistance.

Successful everolimus-eluting stent implantation into the left main trunk stenosis in the anomalous coronary artery after neo-aortic valve replacement in a 6-year-old boy.

CHDs occasionally have coronary complications; however, stent implantation is technically difficult in small children. We reported a successful drug-eluting stent implantation into the congenital anomalous coronary artery in a 6-year-old boy. This treatment is useful for rescuing coronary stenosis, and dual antiplatelet therapy is important to prevent stent restenosis.

Stent unzipping using an ultra-high-pressure balloon: in vitro and animal experiments.

As a child grows, limitations to the maximum dilatable stent diameter (MDD) will result in stenosis associated with size mismatch. If an implanted stent can be intentionally fractured along its length, a process called "unzipping," it may eventually be redilated to adult vessel size. Few studies have addressed how a stent can be unzipped using an ultra-high-pressure balloon (UHB) with the smallest balloon diameter. Eleven commercially available stents, three Liberté stents (LS), six genesis renal stents (GS), and two express vascular SD stents (ES), were tested for in vitro unzipping. In addition, using eight stents, we investigated whether a balloon that had unzipped the stent in vitro would work similarly in the vessel of a pig. Finally, we assessed the histological influence of the unzipped stent on the surrounding tissue. In a bench test, LS, GS, and ES were consistently unzipped by a balloon whose diameter was ≥ 1.5, 2.18, and 1.66 times that of MDD, respectively. In animal experiments, LS, GS, and ES were predictably unzipped with balloons of 1.50, 1.81, and 1.66 times the MDD, respectively. After unzipping, the unzipped strut did not damage the surrounding tissue histologically. Use of a UHB enabled unzipping of the stent with a balloon diameter less than two times the MDD enables implantation of a larger stent in the unzipped small stent by incremental steps.

Successful simultaneous transcatheter treatment for a secundum atrial septal defect complicated by valvular pulmonary stenosis in an infant.

Only few reports have described successful simultaneous transcatheter intervention for CHD in infants. We present an infant with secundum atrial septal defect complicated by valvular pulmonary stenosis. Percutaneous transcatheter pulmonary valvuloplasty was performed first, followed by transcatheter closure of the secundum atrial septal defect uneventfully. Simultaneous transcatheter correction is an effective therapeutic option even in infants.

Static balloon atrial septostomy for the purpose of left heart intervention in postoperative adult CHD.

Background and purposeStatic balloon atrial septostomy is a widely accepted intervention for children with CHD. Successful surgical palliation is creating increasing numbers of adult CHD patients who need subsequent left heart intervention requiring transseptal access. In these patients, the interatrial septum is usually thick and fibrotic because of a previous open heart surgery or catheter intervention, and conventional transseptal puncture may be unsuccessful. Static balloon atrial septostomy to access the left atrium may facilitate intervention via the interatrial septum in such situations. The purpose of this study was to investigate the usefulness and the safety of static balloon atrial septostomy, and the evolution of an iatrogenic atrial septal defect post procedure in adult CHD. METHODS: We retrospectively reviewed six procedures in five adults with CHD and collected demographic characteristics, details of the procedures, clinical outcome, and size changes of the iatrogenic atrial septal defect. RESULTS: The mean age at the time of the procedure was 35 years. The intended primary interventions were pulmonary vein isolation, stenting for pulmonary vein obstruction, and catheter ablation for focal atrial tachycardia. All static balloon atrial septostomies were effective, and the left heart interventions were successfully achieved via transseptal sheaths. There were no major complications associated with the static balloon atrial septostomy. There were no adverse clinical outcomes related to iatrogenic atrial septal defect, and the size of the defects regressed over time in all cases. CONCLUSIONS: Static balloon atrial septostomy can be a safe and useful technique in adult CHD patients needing left heart procedures. The thick interatrial septum found in postoperative patients may reduce the risk of persistent iatrogenic atrial septal defect.

Morphological and Hemodynamic Effectiveness of Stenting for Pulmonary Artery Stenosis　- Subanalysis of JPIC Stent Survey.

BACKGROUND: Percutaneous stenting for branch pulmonary artery stenosis is an established interventional choice in congenital heart disease. The apparent morphologic change in the vessel diameter often differs from the hemodynamic result. METHODS AND RESULTS: We performed a subanalysis of the data from the Japanese Society of Pediatric Interventional Cardiology (JPIC) stent survey. The factors that may have contributed to morphologic effectiveness included reference vessel diameter (RVD), minimum lumen diameter (MLD) and percent diameter stenosis (%DS) and the relation between morphologic and hemodynamic effectiveness was evaluated in 206 lesions treated with stenting. We defined a "50% increase in MLD" as "morphologically effective", while "achievement of either a reduced pressure gradient greater than 50% or an increase of perfusion ratio to the affected side to the contralateral side greater than 20%" as "hemodynamically effective". Morphologic effectiveness was achieved in 84% of patients. Before stenting, %DS was significantly larger, while RVD was smaller in the "effective" group than in the "non-effective" group. The cutoff value for effective stenting was 51% for %DS and 14.7 mm for RVD before stenting. Hemodynamic effectiveness was obtained more often in the "morphologic effective" group. CONCLUSIONS: RVD and %DS were the 2 main contributors to acute morphologic effectiveness. There was a significant relationship between "morphologic effectiveness" and "hemodynamic effectiveness", judging from increased perfusion of the affected lung and/or decreased pressure gradient. (Circ J 2016; 80: 1852-1856).

Current trends in stenting for aortic coarctation in Japan: Subanalysis of Japanese Society of Pediatric Interventional Cardiology (JPIC) stent survey.

BACKGROUND: Stenting for aortic coarctation (CoA) has been accepted as an alternative to surgery for adolescents and adults, but only a few case have been reported in Japan. The purpose of this study was to provide a detailed review of Japanese national data on stenting of CoA. METHODS: In a subanalysis of the data of the Japanese Society of Pediatric Interventional Cardiology (JPIC), we identified 35 patients with CoA who underwent stenting. We analyzed procedural characteristics including factors that may have contributed to hemodynamic effectiveness, and we compared these parameters between the patients under and over 15 years of age. RESULTS: The mean ratio of balloon diameter/minimum lumen diameter (MLD) before stenting was 1.7 (range, 1.2-4.0), and the mean difference between the balloon diameter and the reference vessel diameter was -0.7 mm (range, -5.0 to +3.0 mm). %MLD/balloon diameter, which was defined as [(balloon diameter - MLD after dilation)/balloon diameter] × 100 predicted achievement of <10 mmHg pressure gradient after stenting. The sensitivity and the specificity of its cut-off of 7% were 93% and 47% (AUC, 0.7), respectively. There was no statistical difference between the two age groups under and over 15 years of age, in terms of selection criteria of stent size, balloon type used for deployment and immediate angiographic and hemodynamic result. CONCLUSIONS: Stenting for CoA was clinically effective with few complications in Japan, even in patients not fully grown.

Novel curved balloon catheter for dilating postoperative angled lesions associated with congenital heart disease.

OBJECTIVES: This study aimed to analyze the surface stress generated by a novel curved balloon and assess its efficacy for treating angular lesions associated with congenital heart disease. BACKGROUND: Obstructions at the anastomosis of aortopulmonary shunts and cavopulmonary connections may occur postoperatively. Catheter interventions are often performed for such lesions; however, acute angulation may cause balloon slippage or inappropriate stress on the vessel wall. METHODS: We dilated the curved balloon in a curved vessel model and measured the resultant wall stress and its distribution. Clinical evaluations were performed using this balloon in angled lesions. RESULTS: In the curved vessel model, curved balloons generated uniform stress on the lesser and greater curvatures (curved type, lesser/greater = 0.343 MPa/0.327 MPa; P = 0.61), whereas straight balloons caused disproportionate stress (straight type, lesser/greater = 0.358 MPa/0.254 MPa; P = 0.19). However, the difference in average stress was not statistically significant. Furthermore, the stress was uniform along the entire length of the curved balloon, but differed between the mid and end portions of the straight balloon. Curved balloon dilations were performed for 10 lesions in 7 patients. The curved balloon conformed well to the angulated lesion without slipping. The median percent change in the minimal lumen diameter (MLD) was 64% (range, 0-206%). In 5 lesions, MLD increased by ≥50%. Oxygen saturation increased by 5% (0-9%). CONCLUSIONS: Although further clinical evaluation is necessary, this novel curved balloon may be a reasonable alternative in angled lesions, providing better conformability and preventing excessive stress to the vessel wall adjacent to the stenosis.

Abdominal aortic intima-media thickness in preschool children born preterm.

Recently aortic intima-media thickness (IMT) has been used as an earlier marker of preclinical atherosclerosis in high-risk children, such as those with type 1 diabetes mellitus and hypercholesterolemia. Children who were born preterm have an early elevation in insulin resistance, which may be a risk factor for metabolic syndrome in adulthood. However, there is no optimal marker of subsequent cardiovascular disease for children born preterm. In this study, we aimed to evaluate the effect of preterm birth on aortic IMT during the preschool period. Mean aortic IMT was measured by ultrasound in 26 subjects born preterm (gestational age <37 weeks [preterm group]) and 11 control subjects born at term (term group). The mean aortic IMT of the preterm group was significantly thicker than that of the term group (preterm group: median 577 µm, interquartile range (524-599) versus term group: 517 µm (442-544); p = 0.003). Mean aortic IMT may be one of the earlier markers of subclinical vasculopathy in preschool children who were born preterm.

Recurrent protein-losing enteropathy complicated by postural right subclavian vein compression and right-sided thoracic duct.

We report the case of a 16-year-old female patient with protein-losing enteropathy that was suspected to be caused by thoracic duct congestion associated with postural compression of right subclavian vein. Non-contrast magnetic resonance lymphangiography showed that the thoracic duct connected to the right-sided venous angle of the right subclavian vein which was obstructed when her right arm was lifted. In this case, comprehensive screening of the lymphatics using non-contrast magnetic resonance lymphangiography, which is a minimally invasive tool with high spatial resolution, was helpful for the recognition of the specific pathophysiology. Learning objective: Lymphatic disorders associated with congenital heart disease can be fatal. The morphology and dysfunction of the lymphatic system are complicated, and when added to the complex hemodynamics inherent to congenital heart disease, the pathophysiology is more difficult to understand. To understand the complexity of the lymphatic disease, it is necessary to learn a systematic diagnostic process of lymphatic disorders. In the present case, it is beneficial to know the usefulness of non-contrast magnetic resonance lymphangiography to screen overall lymphatics.

Isolated right ventricular hypoplasia associated with cyanotic atrial septal defect: a case report.

Background: Hypoxaemia in isolated right ventricular (RV) hypoplasia (IRVH) is primarily caused by a right-to-left shunt (RLS) at the atrial level, such as an atrial septal defect (ASD). When considering closure of the RLS, it should be closed only after ensuring that it will not cause right-sided heart failure (HF). Case summary: A 21-year-old woman had been experiencing shortness of breath during exertion since childhood. Transthoracic and transoesophageal echocardiography revealed an ASD with bidirectional shunting, and microbubble test revealed a marked RLS. Cardiac magnetic resonance imaging revealed a hypoplastic RV end-diastolic volume corrected for body surface area of 47 mL/m2 (70% of normal range). Right heart catheterization revealed a decreased Qp/Qs ratio of 0.89 and a pressure waveform with a clear increase in the 'A'-wave, although the mean right atrial pressure was not high (4 mmHg). Therefore, the patient was diagnosed with cyanotic ASD and IRVH. A temporary balloon occlusion test was performed to evaluate the right-sided heart response to capacitive loading prior to ASD closure. After treatment, the patient's improved markedly. The pre-operative brain natriuretic peptide (BNP) level was normal; however, 6 months after ASD closure, the BNP level was elevated, and the continuous-wave Doppler waveform of pulmonary regurgitation at the time of transthoracic echocardiography changed, suggesting an increase in diastolic RV pressure. Discussion: When ASD is complicated by hypoxaemia, the possibility of IRVH, although rare, should be considered. Another difficult point is determining whether the ASD can be closed, considering its immature RV compliance.