Prevalence of bleeding events in real-world Japanese registry for Percutaneous Ventricular Assist Device.

PURPOSE: Bleeding complication is a critical risk factor for outcomes of acute heart failure patients requiring mechanical circulatory support (MCS), including percutaneous catheter-type heart pumps (Impella). The Japanese registry for Percutaneous Ventricular Assist Device (J-PVAD) is an ongoing, large-scale, real-world registry to characterize Japanese patients requiring Impella. Here we analyzed bleeding complication profiles in patients who received Impella. METHODS: All consecutive Japanese patients who received Impella from October 2017 to January 2020 were enrolled. The 30-day survival and bleeding complications were analyzed. RESULTS: A total of 1344 patients were included: 653 patients received Impella alone, 685 patients received a combination of veno-arterial extracorporeal membrane oxygenation and Impella (ECPELLA), and 6 patients had failed Impella delivery. Overall 30-day survival was 67.0%, with Impella alone at 81.9% and ECPELLA at 52.7%. Overall bleeding/hematoma adverse events with a relation or not-excluded relation to Impella was 6.92%. Among them, the rates of hematoma and bleeding from medical device access sites were 1.41% and 4.09%, respectively. There was no difference between etiologies for these events. CONCLUSION: This study represents the first 3-year survival and the safety profile focused on bleeding adverse events from the J-PVAD registry. The results show that the real-world frequency of bleeding adverse events for patients who received Impella was an expected range from previous reports, and future real-world studies should aim to expand this data set to improve outcomes and adverse events.

Short-Term Outcomes of Impella Support in Japanese Patients With Cardiogenic Shock Due to Acute Myocardial Infarction　- Japanese Registry for Percutaneous Ventricular Assist Device (J-PVAD).

BACKGROUND: The Impella®percutaneous left ventricular assist device has been available in Japan since 2017. This is the first large-scale registry study to analyze the efficacy and safety of Impella in Japanese patients with acute myocardial infarction with cardiogenic shock (AMICS).Methods and Results: The Japanese registry for Percutaneous Ventricular Assist Device (J-PVAD) has registered all consecutive Japanese patients treated with Impella. We extracted data for 593 AMICS patients from J-PVAD and analyzed 30-day survival and safety profiles. Overall 30-day survival was 63.1%. The 30-day survival of the Impella alone and Impella plus venoarterial extracorporeal membrane oxygenation (ECPELLA) groups was 80.9% and 45.7%, respectively. The Impella alone group was older and had a lower rate of cardiac arrest, milder consciousness disturbance, less inotrope use, lower serum lactate concentrations, higher B-type natriuretic peptide concentrations, and higher left ventricular ejection fraction (LVEF) than the ECPELLA group. Cox regression analysis revealed that older age and comorbid renal disturbance were common risk factors affecting 30-day mortality in both groups. Major adverse events were hemolysis (10.8%), hemorrhage/hematoma (7.6%), peripheral ischemia (4.4%), stroke (1.3%), and thrombosis (0.7%). LVEF improved in both groups during support. CONCLUSIONS: AMICS treatment with Impella showed favorable 30-day survival and safety profiles. The survival rate of patients treated with Impella alone was particularly high. Further studies are needed to improve outcomes of patients with ECPELLA support.

Three-year experience of catheter-based micro-axial left ventricular assist device, Impella, in Japanese patients: the first interim analysis of Japan registry for percutaneous ventricular assist device (J-PVAD).

Catheter-based micro-axial ventricular assist device Impella® (Abiomed, Danvers, MA) has been used in Japanese patients with drug-refractory acute heart failure (AHF) since 2017. This is the first interim analysis of the ongoing Japan Registry for Percutaneous Ventricular Assist Device (J-PVAD) to investigate the safety and efficacy of Impella support. Between October 2017 and January 2020, 823 Japanese patients, who were treated with the Impella 2.5, CP, or 5.0 pump, were enrolled. The primary endpoints were safety profiles and cumulative 30-day survival. Among them, 44.8% of patients were acute myocardial infarction with cardiogenic shock. The Impella pumps were unable to implant in 4 patients. The Impella 2.5, CP, and 5.0 pumps were used in 72.4%, 6.2%, and 16.6%, respectively, and mean support duration was 8.1 ± 10.2 days. Combination use of Impella and venoarterial extracorporeal membrane oxygenation (VA-ECMO) was applied for 387 patients (47.3%). Pump stop occurred 22 patients (2.7%). Major adverse events included hemolysis (11.2%), hemorrhage/hematoma (6.1%), peripheral ischemia (1.6%), and stroke (1.6%). The overall 30-day survival was 62.2%. Survival of patients with single Impella support was significantly higher than patients with Impella combined with VA-ECMO support (81.1% vs 49.6%; p < 0.01), who had lower blood pressure, lower left ventricular ejection fraction, and higher degree of inotropic support. Results suggest that short-term outcome of Impella support for Japanese patients was favorable with acceptable safety profiles.

Partnership Between Japan and the United States for Early Development of Pediatric Medical Devices　- Harmonization By Doing for Children.

BACKGROUND: The Harmonization By Doing (HBD) program was established in 2003 as a partnership among stakeholders of academia, industry and regulatory agencies in Japan and the United States, with a primary focus on streamlining processes of global medical device development for cardiovascular medical devices. While HBD has traditionally focused on development of devices intended to treat conditions prevalent in adults, in 2016, HBD established the "HBD-for-Children" program, which focuses on the development of pediatric devices as the development of medical devices for pediatric use lags behind that of medical devices for adults in both countries.Methods and Results:Activities of the program have included: (1) conducting a survey with industry to better understand the challenges that constrain the development of pediatric medical devices; (2) categorizing pediatric medical devices into five categories based on global availability and exploring concrete solutions for the early application and regulatory approval in both geographies; and (3) facilitating global clinical trials of pediatric medical devices in both countries. CONCLUSIONS: The establishment of the HBD-for-Children program is significant because it represents a global initiative for the introduction of pediatric medical devices for patients in a timely manner. Through the program, academia, industry and regulatory agencies can work together to facilitate innovative pediatric device development from a multi-stakeholder perspective. This activity could also encourage industry partners to pursue the development of pediatric medical devices.

Establishment of a Healthcare System for Patients With Adult Congenital Heart Disease in Collaboration With Children's Hospital　- The Nagano Model.

BACKGROUND: Despite the best efforts of pediatricians, healthcare for adult patients with congenital heart disease (ACHD) has proven challenging because of the increased numbers. This study presents the process of establishing an ACHD care system as a collaborative effort between Shinshu University Hospital and Nagano Children's Hospital. Methods and Results: Establishing an outpatient clinic for transition, a cooperation agreement for in-patient care between the 2 hospitals, and quality management of diagnostic imaging and educational meetings for adult cardiologists were the 3 major challenges. Of the 99 patients who visited the transition clinic in the children's hospital between May 2014 and December 2016, 3 returned to the pediatrician's clinic. Between June 2013 and December 2017, 273 patients visited the ACHD center in Shinshu University Hospital. Until December 2017, mortality and fatal arrhythmia were noted in 3 and 2 cases, respectively. Catheter ablation for arrhythmia was performed in 12 cases, and 4 cases of pregnancy with moderate/severe ACHD or estimated as high risk were managed with healthy livebirths. Surgical interventions for moderate/severe ACHD were performed in collaboration with the children's hospital or Sakakibara Heart Institute. CONCLUSIONS: Patients were successfully transferred to adult cardiology departments. Surgical and nonsurgical interventions for ACHD were provided. Collaboration between adult and pediatric cardiologists assists in the establishment of healthcare systems for ACHD.

Neo-aortic insufficiency late after staged reconstruction for hypoplastic left heart syndrome: impact of differences in initial palliative procedures.

The neo-aortic insufficiency in patients with hypoplastic left heart syndrome is an important sequela. We assessed the risks of the neo-aortic valve deterioration by the difference of initial palliations: Group I underwent primary Norwood (Nw) with systemic-to-pulmonary artery shunt (SPS), Group II underwent bilateral pulmonary artery banding (bPAB) and subsequent Nw with SPS (bPAB-Nw/SPS), Group III underwent bPAB and subsequent Nw with bidirectional Glenn (BDG) procedure (bPAB-Nw/BDG). The neo-aortic valve z score changes over time did not reach statistical significance in all groups (p = 0.43 for Group I, 0.20 for Group II, and 0.30 for Group III). The degree of neo-aortic valve insufficiency did not change significantly over time during this period except for Group III (p = 0.34 for Group I, 0.20 for Group II, and 0.02 for Group III). On the other hand, dimensions of the neo-aortic annulus and degrees of neo-aortic insufficiency did not differ significantly among the 3 groups at any pre-determined time. The presence or absence of incision into the sino-tubular junction at Nw did not affect the late neo-aortic valve z score or insufficiency. These data indicate that the difference of initial palliative procedures does not affect late neo-aortic valve insufficiency in Nw survivors. Because valve failure may develop in longer follow-up, further observation should be conducted.

Validation of numerical simulation methods in aortic arch using 4D Flow MRI.

Computational fluid dynamics (CFD) are the gold standard in studying blood flow dynamics. However, CFD results are dependent on the boundary conditions and the computation model. The purpose of this study was to validate CFD methods using comparison with actual measurements of the blood flow vector obtained with four-dimensional (4D) flow magnetic resonance imaging (MRI). 4D Flow MRI was performed on a healthy adult and a child with double-aortic arch. The aortic lumen was segmented to visualize the blood flow. The CFD analyses were performed for the same geometries based on three turbulent models: laminar, large eddy simulation (LES), and the renormalization group k-ε model (RNG k-ε). The flow-velocity vector components, namely the wall shear stress (WSS) and flow energy loss (EL), of the MRI and CFD results were compared. The flow rate of the MRI results was underestimated in small vessels, including the neck vessels. Spiral flow in the ascending aorta caused by the left ventricular twist was observed by MRI. Secondary flow distal to the aortic arch was well realized in both CFD and MRI. The average correlation coefficients of the velocity vector components of MRI and CFD for the child were the highest for the RNG k-ε model (0.530 in ascending aorta, 0.768 in the aortic arch, 0.584 in the descending aorta). The WSS and EL values of MRI were less than half of those of CFD, but the WSS distribution patterns were quite similar. The WSS and EL estimates were higher in RNG k-ε and LES than in the laminar model because of eddy viscosity. The CFD computation realized accurate flow distal to the aortic arch, and the WSS distribution was well simulated compared to actual measurement using 4D Flow MRI. However, the helical flow was not simulated in the ascending aorta. The accuracy was enhanced by using the turbulence model, and the RNG k-ε model showed the highest correlation with 4D Flow MRI.

Clinical Features of Acute and Fulminant Myocarditis in Children　- 2nd Nationwide Survey by Japanese Society of Pediatric Cardiology and Cardiac Surgery.

BACKGROUND: The 1st nationwide survey by the Japanese Society of Pediatric Cardiology and Cardiac Surgery of acute or fulminant myocarditis (AMC/FMC) in children revealed that the survival rate of FMC was only 51.6%. The 2nd nationwide survey was performed to evaluate the recent outcomes of pediatric myocarditis.Methods and Results:Questionnaires regarding patients aged ≤18 years with AMC/FMC during the period from January 2006 to December 2011 were mailed. A total of 221 cases (age 6.5±5.3 years, 116 boys and 105 girls) were reported. There were 145 (65.6%) and 74 cases (33.5%) of AMC/FMC, respectively; the type of myocarditis was not reported in the remaining 2 cases (0.9%). Viruses were identified in 56 cases (25.3%), including coxsackie B in 9 and influenza A in 8. Histopathology by either endomyocardial biopsy or autopsy was obtained in 38 cases (19.2%). Intravenous immunoglobulin was effective in 49 (34.3%) of 143 cases. Steroid therapy was effective in 20 (32.8%) of 61 cases. Mechanical circulatory support was given in 54 cases (24.4%) and 94.2% of them were patients with FMC. The survival rates for the whole study population, acute myocarditis, and FMC were 75.6%, 91.0%, and 48.6%, respectively. CONCLUSIONS: The survival rate of children with myocarditis was almost identical to that of 10 years ago. (Circ J 2016; 80: 2362-2368).

Pretransplant-corrected QT dispersion as a predictor of pericardial effusion after pediatric hematopoietic stem cell transplantation.

Pericardial effusion is a potentially fatal complication following hematopoietic stem cell transplantation (HSCT). Therefore, the identification of risk factors could improve the outcome. Prolonged QT dispersion (QTD) and corrected QTD (QTcD) are associated with serious arrhythmias and sudden death in many forms of heart disease. However, no study has evaluated the efficacy of QTD and QTcD to predict pericardial effusion post-HSCT. We studied 89 pediatric HSCT patients to identify preoperative risk factors for pericardial effusion with particular focus on QTD and QTcD. Pericardial effusion occurred in 15 patients (cumulative onset rate: 17.4%) within one year post-HSCT, of which 8 (9.2%) were symptomatic. Patients with pericardial effusion following allogeneic HSCT showed significantly lower overall survival; however, pericardial effusion was not the direct cause of death in any patient. Univariate and multivariate analyses revealed that transplantation-associated thrombotic microangiopathy (TA-TMA) was an independent risk factor for post-HSCT pericardial effusion. In addition, pretransplant QTcD was significantly prolonged in the pericardial effusion group. These results suggest that pediatric patients with abnormally prolonged QTcD before the preparative regimen for HSCT should be regularly followed-up by echocardiography to detect pericardial effusion, particularly when accompanied by complications including TA-TMA.

Notable alkaline tolerance of Kocuria marina isolate from blood of a pediatric patient with continuous intravenous epoprostenol therapy.

This study was the first to describe the hitherto deficiently evaluated alkaline tolerance of Kocuria marina isolate from a pediatric patient with continuous intravenous epoprostenol dosing therapy. Our isolate from blood of a 7-year-old Japanese boy was finally identified as K. marina by the morphological, cultural, and biochemical properties together with the comparative sequence analyses of the 16S rRNA genes. The K. marina isolate, the causative agent of catheter-related blood-stream infection, was not only revealed to be salt tolerant (NaCl 15%), but also demonstrated to be stably survived with no apparent decrease of cell counts for long periods (120 h) in an alkaline environment (pH 8, 9, 10, and 11) at 35 °C. Its remarkable tolerance to the stresses of high alkalinity compared with a clinical Staphylococcus aureus strain should provide consistent interpretation that the environment of high alkalinity (pH 10.2-10.8) measures should be insufficient to inactivate almost all the causative agents including K. marina strains in the solution of epoprostenol (pH 10.4) (Flolan(®), GlaxoSmithKline, Ltd., Tokyo, Japan.). To the best of our knowledge, the first description of the property of being tolerant to high alkalinity that the K. marina isolate exhibited was noteworthy and a useful piece of information. In conclusion, we believe that the present study should be a notification regarding the potential risk of catheter-related blood-stream infections due to K. marina, suggestive of an alkalophile, especially in patients receiving continuous intravenous epoprostenol dosing therapy.

Assessment of the developmental change in the left atrial volume using real time three-dimensional echocardiography.

AIMS: Real time 3D echocardiography (RT3DE) has been applied for the assessment of left atrial (LA) function in patients with adult heart disease; however, LA function is not well known in children. We aimed at determining the normal range of LA volume (LAV) using RT3DE and the feasibility and reproducibility of this method in healthy subjects and at elucidating the developmental changes in the LAV with aging. METHODS AND RESULTS: In this study, 359 healthy people (mean age, 23.9 ± 21.3; range, 0.1-76.4 years) were enrolled. We performed transthoracic RT3DE and measured the maximum and minimum LAV. Simultaneously, we measured the LAV using the 2D biplane Simpson's method. Inter-observer and intra-observer variability and the agreement of LAV measurements between RT3DE and 2DE were assessed in a subset of subjects. The RT3DE feasibility for LAV measurement was 93%. Both maximum and minimum LAVs exponentially increased with age and linearly increased with increasing of body surface area (BSA). The LA distensibility, which demonstrates LA reservoir function, decreased with age and BSA. The LAVs measured by RT3DE were significantly smaller than those measured by the 2D biplane Simpson's method. The 3D volumetric method had favorable intra-observer and inter-observer agreement. CONCLUSION: The reference values of LAV from early infancy to adulthood were obtained using RT3DE, which could be useful for future studies in children with congenital heart disease. RT3DE is a reproducible method and a feasible tool for evaluating the LAV in children. LA reservoir function is likely to decrease with age and increasing of body size.

Interleukin-8-producing primary cardiac undifferentiated sarcoma in a child with sustained fever.

We report the case of a 12-year-old boy with primary undifferentiated sarcoma of the left atrium. He had sustained fever during the clinical course and multiple lung and brain metastases. Chemotherapy and irradiation were ineffective; he died 41 days after hospitalization. On retrospective analysis, interleukin-8 (IL-8) was elevated; this was supported by immunohistochemistry and gene expression analysis of tumor samples. IL-8 continued to increase with tumor progression accompanied by elevated neutrophil count and C-reactive protein. IL-8 is involved in malignant tumor proliferation, migration, and angiogenesis and may have been related to the clinical condition and prognosis in the present case.

Current trends in use of implantable cardioverter defibrillators and cardiac resynchronization therapy with a pacemaker or defibrillator in Japanese pediatric patients: results from a nationwide questionnaire survey.

BACKGROUND: In Japan, the use of implantable cardioverter defibrillators (ICDs), cardiac resynchronization therapy with a biventricular pacemaker (CRTP) and CRT with a defibrillator (CRTD) in children has not been studied statistically, and dual-chamber (DDD) pacemakers are still used for pediatric CRT because of current government regulations. METHODS AND RESULTS: Data were obtained from 15 children's and 74 general hospitals through a questionnaire survey regarding the aforementioned therapies performed before 2012 in Japanese children (<16 years old). ICD, CRT with DDD, CRTP and CRTD were used in 64 (42%), 47 (31%), 34 (22%) and 7 (5%), respectively, of all cases reported (n=152). Among all CRTP and CRT-DDD cases (n=81), the use of DDD accounted for 41% in general hospitals vs. 89% in children's hospitals, and CRT-DDD and CRTP were effective in 67 cases (83%). Of 64 ICD cases, appropriate shocks were experienced in 28 cases (44%), and inappropriate shocks in 19 cases (29%). Additionally, data from the Japan Arrhythmia Device Industry Association obtained for overall device usage analysis revealed that CRTP was more commonly used in children than in adults. CONCLUSIONS: There is an increasing need for pediatric device therapy, especially CRTP. However, many children's hospitals were still using DDD pacemakers in 2012. Although the demand for device therapy in children may be small, it is indispensable in pediatric cardiology.

Outcomes of Veno-Arterial Extracorporeal Membrane Oxygenation With Percutaneous Left Ventricular Unloading in Fulminant Myocarditis.

Fulminant myocarditis requiring peripheral veno-arterial extracorporeal membrane oxygenation (VA-ECMO) has a high mortality rate. We investigated clinical outcomes of combined use of VA-ECMO and percutaneous left ventricular assist device (VAD) (Impella) for fulminant myocarditis in 104 consecutive patients enrolled in the Japan Registry for Percutaneous VAD (J-pVAD) between October 2017 and January 2020. Patients were followed until hospital discharge and predictors of survival were analyzed with a Cox proportional hazards model. The median support duration of combined use of VA-ECMO and Impella (ECMO/Impella) was 6 days, and the median left ventricular ejection fraction improved from 15% to 52% during support ( p < 0.0001). Overall, 66 patients (63%) survived to discharge. Multivariate analysis revealed ECMO/Impella support at a transplant center as an independent predictor of survival ( p = 0.0231). Patients treated at transplant centers had better 60 days survival rates when compared to nontransplant centers (83% vs. 55%, p = 0.005). However, baseline characteristics and treatment strategies differed between the two groups. This real-world national registry database suggested the difference in survival after ECMO/Impella support for fulminant myocarditis between transplant and nontransplant centers, which may indicate hospital variations regarding patient management, although further controlled studies are needed.

Comparison of the clinical presentation, treatment, and outcome of fulminant and acute myocarditis in children.

BACKGROUND: Myocarditis (MC) is an important cause of cardiac dysfunction in children. Fulminant MC is sometimes fatal, and sequelae may develop during follow-up. We conducted a nationwide survey to determine the clinico-epidemiological features of MC in Japanese children and adolescents. METHODS AND RESULTS: Survey questionnaires were mailed to 627 hospitals, which were asked if they had treated MC patients aged between 1 month and 17 years during the period from January 1997 through December 2002. Responses were collected until December 2005, and data were collected and analyzed until January 2008. A total of 169 patients were reported: 64 fulminant cases, 89 acute cases, and 8 chronic cases. Incidence was 43.5 cases/year and 0.26 cases/100,000. Pathogens were identified in 37 patients; coxsackie virus accounted for 60%. Major cardiovascular manifestations at onset were congestive heart failure, refractory arrhythmia, and syncope in 70, 37, and 17 patients, respectively. Intravenous immunoglobulin was administered to 73 patients. Mechanical support seemed to be effective and life-saving. Among the 169 patients, 123 survived. Cardiovascular sequelae were reported in 49 patients. CONCLUSIONS: The survival rate for children with fulminant MC was disappointing. Overall, two-thirds of survivors had no sequelae. Mechanical support may reduce the mortality and the risk of clinical worsening.

Automated analysis method to assess pulmonary blood flow distribution using conventional X-ray angiography.

Quantitative assessment of the right-to-left ratio of pulmonary blood flow distribution is important for determining the clinical indications for treating pulmonary arterial branch stenosis. A novel theory was recently proposed that can be used to quantitatively assess the right-to-left ratio on conventional X-ray angiography images. In the proposal, further developments were indicated, especially automated calculation. In this study, a new automated algorithm was developed. In the X-ray image, regions of interest were set in right and left lung, and time-signal intensity curves were measured. The new automated algorithm is applied to determine the optimal time window for the analysis of the time-signal intensity curve and to calculate the slope of the curve in the optimized time window. The right-to-left ratios in seven consecutive patients calculated by the new automated algorithm were compared to those calculated by lung perfusion scintigraphy. The ratios were in good agreement with linear regression with a slope of 1.27 and a Pearson correlation coefficient of 0.95. The processing time was less than 10 s, which is one-eighth of the manual processing time. The new automated algorithm is accurate, stable, and fast enough for clinical use in the real world.