Application of two-dimensional temperature response functions for reconstruction of divertor heat flux profile in commercial fusion reactors

To keep the tritium breeding rate TBR > 1 and to meet the high heat load and neutron shielding requirements for the first wall and divertor in fusion demonstration (DEMO) reactors, the number of port plugs and other openings must be limited. To accomplish this, it is necessary to develop alternatives to the use of infrared (IR) thermography to determine the peak heat flux and the heat flux profile onto divertor targets. A divertor tile equipped with multiple temperature monitoring channels can be used to reproduce the temperature profile. To avoid the high temperatures and high neutron flux environment in a DEMO, the monitoring positions can be set well away from the irradiated surface. However, the spatial resolution of this method is lower than that provided by IR thermography. In the present work, we apply two-dimensional temperature response functions and the corresponding heat conduction model to temperature data obtained from a divertor tile surface in the large helical device to study the effects of the spatial resolution of the monitored temperature profile on the reconstructed heat flux profile. The findings provide information that will be useful in defining a method for embedding thermocouples into the divertor tiles of future DEMO reactors.

Difficulty in diagnosing peritonitis caused by multidrug-resistant tuberculosis

Key Clinical Message

The low sensitivity of ascites culture for acid-fast bacilli necessitates a peritoneal biopsy when tuberculous peritonitis is suspected. Findings in the peritoneum on computed tomography may prompt suspicion of tuberculous peritonitis.

Abstract

A 47-year-old Nigerian man presented with fever, abdominal distention, and weight loss. Abdominal computed tomography revealed massive ascites and peritoneal thickening. Despite failing to culture acid-fast bacilli from ascites, histological examination and culture of peritoneum revealed multidrug-resistant tuberculosis peritonitis. Peritoneal biopsy is mandatory when tuberculosis peritonitis is suspected.

Optimization of a fast deuterium diagnostic method based on visible energetic 3He spectroscopy for high electron density plasmas

Fast ions play a crucial role in plasma heating, and their behavior in the plasma must be accurately understood. A diagnostics method based on charge exchange emission from the n = 4 - 3 transition (λ0 = 468.6 nm) of energetic 3He produced by the deuteron-deuteron reaction has been proposed as a for fast deuterons with energies in the order of MeV. The proposed method has the following advantages: No beam emission interferes with the spectra, the direction of the measuring line of sight, and the injection angle of the diagnostic beam can be freely determined. In previous studies, due to competing bremsstrahlung, it was expected that the proposed method will not be practical in the case of high electron density operation. This paper makes the proposed method available for measurement even at high electron densities by optimizing the measurement line of sight direction and the diagnostic beam incidence angle. This allows an electron density five times larger than the range of applications shown in previous studies. This result will contribute to measure of DT alpha in ITER.

Prevalence and distribution of non-pulmonary vein atrial fibrillation triggers in real-world clinical settings

Background

Epidemiology of non-pulmonary vein (PV) triggers of atrial fibrillation (AF) is not fully known.

Purpose

This study aimed to clarify the prevalence and distribution of non-PV triggers in real-world clinical settings of AF catheter ablation.

Methods

One-thousand and twenty patients undergoing AF ablations were retrospectively analyzed (mean age 65 years old, 702 males (69%), 506 paroxysmal and 514 non-paroxysmal). Induction and observation of AF triggers were attempted using intravenous isoproterenol/adenosine triphosphate and repeated direct current cardioversion during AF in each session. Documentable non-PV AF triggers were characterized in the studied population. Premature atrial contractions that did not initiate AF were excluded.

Results

A hundred and twenty-six non-PV triggers were documented in 108 patients (10.6%). Non-PV trigger was documented in 6.3% of 1st session cases, whereas 30.9% of recurrent cases undergoing multiple sessions (p<0.0001). Left atrial (LA) posterior wall was the most prevalent site (N=34), followed by 30 intra-atrial septum (IAS), 29 superior vena cava (SVC), 13 crista terminalis, 7 right atrial (RA) free wall, 6 LA anterior wall, 3 coronary sinus (CS), 3 left atrial appendage, and 1 persistent left superior vena cava (LSVC). We classified those non-PV triggers into 4 groups; 43 LA, 33 thoracic veins (SVC, CS and LSVC), 30 IAS and 20 RA. Thoracic vein/RA origins were more prevalently detected in paroxysmal AF cases (57%) compared to non-paroxysmal AF (28%) (p<0.01). Conversely, LA origin was more prevalently detected in non-paroxysmal AF cases (48%) compared to paroxysmal AF (20%) (p<0.01).

Conclusions

Prevalence of non-PV trigger in cases undergoing multiple sessions is extremely high, suggesting a particular importance of non-PV trigger targeting in patients with recurrent AF undergoing 2nd or 3rd ablation sessions. Progressive nature of AF with newly generated AF triggers should be under consideration. Distributions of non-PV triggers are largely different between paroxysmal and non-paroxysmal AF. These findings may help ablation strategy regarding non-PV trigger targeting in practice.

Funding Acknowledgement

Type of funding sources: None.

Catheter ablation of persistent atrial fibrillation with heart failure improves hemodynamic status without deteriorating renal function in the elderly

Background/Introduction

Atrial fibrillation (AF) and heart failure (HF) frequently coexist in the elderly people, leading to worse clinical outcomes. HF with preserved ejection fraction (HFpEF) is the most common form of HF in the elderly, particularly in women, associated with AF. Ablation of AF in younger patients with HF with reduced EF (HFrEF) has become an established treatment option. However, clinical impact of ablation for persistent AF accompanying with HF in the elderly remains unclear.

Purpose

This study aimed to evaluate the effect of catheter ablation of persistent AF with heart failure in the elderly.

Methods

Consecutive 70 patients who underwent catheter ablation of persistent AF accompanying with HF (NYHA class> II, mean LVEF 51.7%) in our institution were retrospectively analyzed with regards to their 1-year clinical outcomes, HF markers such as BNP, renal function and transthoracic echocardiographic findings. Patients were dichotomized by age of 75-year-old (31 elderly vs 39 younger subjects) and separately analyzed.

Results

Mean age of the studied population was 70.5 year-old; 79.6±3.8 in the elderly group and 63.2±8.5 in the younger group. The elderly patients were more frequently females (45% vs 21%). Longstanding persistent AF was observed in 32% in the elderly and 28% in the younger group. Circumferential pulmonary vein isolation (PVI) was performed in all patients, with additional ablations of liner lesions and/or non-PV foci as needed. PVI alone was observed in 54.8% in the elderly and 41% in the younger group. There were no serious complications associated with the procedure. During 1 year after ablation, recurrence of AF was observed in 15 patients [6/31 (19%) in the elderly, 9/39 (23%) in the younger]. Readmission due to HF was observed in only 1 patient in the elderly and 2 patients in the younger group (3% vs. 5%, respectively). Cardiovascular events were observed in 3 patients [2/31 (6%) in the elderly, 1/39 (3%) in the younger], but there was no death. The BNP level as well as the NYHA class significantly decreased at 1-year follow-up compared to baseline in the both groups (Figure A and B). There was no change in serum creatinine level in the both groups (Figure C). The left atrial dimension and the LA volume index decreased at 1-year follow-up in the both groups (Figure D and E). The LVEF improved only in the younger group (Figure F).

Conclusions

Ablation of persistent AF in the elderly with HF (mostly with preserved EF) was associated with hemodynamic and functional improvements without deteriorating renal function in a mid-term, which was mostly comparable to the results in the younger.

Funding Acknowledgement

Type of funding sources: None.

Aggressive combined pharmacotherapy for heart failure reduces new onset atrial fibrillation

Backgrounds

Heart failure (HF) is a risk factor for new onset atrial fibrillation (AF), and the new onset AF is associated with a worse prognosis in HF patients. It has been reported that renin-angiotensin system inhibitor (RASi), β-blocker and mineral-corticoid receptor antagonist (MRA) prevent the new onset AF in HF patients. However, the effect of combined pharmacotherapy including angiotensin receptor neprilysin inhibitor (ARNI) and sodium glucose co-transporter 2 inhibitor (SGLT2i) on AF is unknown. We investigated the impact of contemporary regimen of combined pharmacotherapy for HF (RASi/ARNI+β-blocker+MRA+SGLT2i) on new onset AF.

Methods and results

We retrospectively studied rEF and mrEF patients without AF admitted to our hospital due to decompensated HF between 2015 and 2021 (n=366). Long-term (The mean follow-up was 635±421 days) incidence of new onset AF was investigated with regard to medical therapies. Patients were divided into 2 groups; patients with ≤2 HF drugs (n=181) and patients with ≥3 HF drugs (n=185). Patients with ≤2 HF drugs group were older (77.3 vs 67.0 years old, P<0.001), had a poorer renal function (Cre: 1.66 vs 1.09 mg/dl, P<0.001), and had a higher rate of ischemic heart disease (52 vs 38%, P=0.009), whereas left ventricular systolic function was better (EF: 31.9 vs 27.3%, P<0.001). There were 19 (10.5%) new onsets AF in the ≤2 HF drugs group, whereas only 7 (3.8%) had new onsets AF in the ≥3 HF drugs group (HR 0.36, 95% CI 0.15–0.85, P=0.01). All-cause death and hospitalization for HF were fewer in the ≥3 HF drugs group. A multivariate analysis revealed that ≥3 HF drugs use was an independent negative predictor of new onset AF (HR 0.37, 95% CI 0.15–0.93, P=0.03). Even after a propensity score matching of the clinical variables, the incidence of new onset AF was consistently fewer in the ≥3 HF drugs group (HR 0.36, 95% CI 0.13–0.99, P=0.04). Finally, patients with new onset AF had a higher rate of hospitalization for HF in the studied population (HR 9.68, 95% CI 5.67–16.5, P<0.01).

Conclusion

Aggressive combined pharmacotherapy for HF may be associated with fewer new onset AF in patients with HF.

Funding Acknowledgement

Type of funding sources: None.

Regional Difference in Myelination in Monocarboxylate Transporter 8 Deficiency: Case Reports and Literature Review of Cases in Japan

Background: Monocarboxylate transporter 8 (MCT8) is a thyroid hormone transmembrane transporter protein. MCT8 deficiency induces severe X-linked psychomotor retardation. Previous reports have documented delayed myelination in the central white matter (WM) in these patients; however, the regional pattern of myelination has not been fully elucidated. Here, we describe the regional evaluation of myelination in four patients with MCT8 deficiency. We also reviewed the myelination status of previously reported Japanese patients with MCT8 deficiency based on magnetic resonance imaging (MRI).

Case Reports: Four patients were genetically diagnosed with MCT8 deficiency at the age of 4–9 months. In infancy, MRI signal of myelination was observed mainly in the cerebellar WM, posterior limb of internal capsule, and the optic radiation. There was progression of myelination with increase in age.

Discussion: We identified 36 patients with MCT8 deficiency from 25 families reported from Japan. The available MRI images were obtained at the age of <2 years in 13 patients, between 2 and 4 years in six patients, between 4 and 6 years in three patients, and at ≥6 years in eight patients. Cerebellar WM, posterior limb of internal capsule, and optic radiation showed MRI signal of myelination by the age of 2 years, followed by centrum semiovale and corpus callosum by the age of 4 years. Most regions except for deep anterior WM showed MRI signal of myelination at the age of 6 years.

Conclusion: The sequential pattern of myelination in patients with MCT8 deficiency was largely similar to that in normal children; however, delayed myelination of the deep anterior WM was a remarkable finding. Further studies are required to characterize the imaging features of patients with MCT8 deficiency.

Fast deuteron diagnostics using visible light spectra of 3He produced by deuteron-deuteron reaction in deuterium plasmas

The fast deuteron (non-Maxwellian component) diagnostic method, which is based on the higher resolution optical spectroscopic measurement, has been developed as a powerful tool. Owing to a decrease in the D-H charge-exchange cross section, the diagnostic ability of conventional optical diagnostic methods should be improved for ∼MeV energy deuterons. Because the ³He-H charge-exchange cross section is much larger than that of D-H in the ∼MeV energy range, the visible light (VIS) spectrum of ³He produced by the dueteron-dueteron (DD) reaction may be a useful tool. Although the density of ³He is small because it is produced via the DD reaction, improvement of the emissivity of the VIS spectrum of ³He can be expected by using a high-energy beam. We evaluate the VIS spectrum of ³He for the cases when a fast deuteron tail is formed and not formed in the ITER-like beam injected deuterium plasma. Even when the beam energy is in the MeV energy range, a large change appears in the half width at half maximum of the VIS spectrum. The emissivity of the VIS spectrum of ³He and the emissivity of bremsstrahlung are compared, and the measurable VIS spectrum is obtained. It is shown that the VIS spectrum of ³He is a useful tool for the MeV beam deuteron tail diagnostics.

Early follow-up visit at outpatient care after discharge improves 2-year heart failure readmission rate and long-term prognosis in patients with decompensated heart failure

Background/Introduction

It has been reported that heart failure (HF) readmission has not declined even with current cardiology practice in the last 10 years. It has been also reported that HF readmission tends to occur shortly after discharge. This may be due to overwork and excessive salt intake after discharge. In other words, it is conceivable that patient factors are largely attributable, which should be intervene for better clinical outcomes.

Purpose

We hypothesized and investigated whether an early follow-up visit at outpatient care within 2 weeks after discharge affects the re-admission rate and prognosis in patients with decompensated HF.

Methods

We retrospectively investigated consecutive 407 hospitalized patients due to decompensated HF. After exclusion of 99 patients with in-hospital death, transfer to another hospital and readmission within 2 weeks after discharge, consecutive 308 out of 407 patients were investigated. Two-year clinical outcomes after discharge were collected and analyzed. An early follow-up was defined as an outpatient care visit within 2 weeks after discharge with the adjustment of drugs and/or the lifestyle guidance, if necessary. A setting of early follow-up in each patient was according to a physician's discretion.

Results

One hundred-twenty eight patients underwent early follow-up visits and other 180 patients were without it. An univariate analysis showed that the early follow-up was significantly associated with a lower HF readmission rate during 2 years (17.1% in the early follow-up group, 34.4% in the control group, p≤0.001, OR=0.397, 95% CI=0.230–0.685, Figure) and a 2-year composite adverse outcome (all cause death and HF readmission; 18.7% vs. 40.5%, p&lt;0.001, OR=0.332, 95% CI=0.196–0.563, Figure). To exclude possible relationships of other co-variable factors, we performed a multivariate analysis about the association with HF readmission rate and the 2-year composite adverse outcome (co-variate factors as follows are included; factors of which p-value was less than 0.1 and general confounding factors). The multivariate analysis showed that the early follow-up was independently associated with HF readmission during 2 years (p=0.002, OR=0.376, 95% CI=0.197–0.716) and the 2-year composite outcome (p&lt;0.001, OR=0.343, 95% CI=0.182–0.648). Finally, we characterized the practical interventions at outpatient care after discharge. Lifestyle guidance was done in all patients. However, medication adjustments were done in only 36.7% patients. Interestingly, whether or not a medication adjustment was done at the early follow-up visit was not associated with the HF readmissions (p=0.781).

Conclusions

The present study suggests that an early follow-up approach after discharge in decompensated HF patients may improve the long-term prognosis. These results were not dependent on whether a medication adjustment was performed or not. An early follow-up may help improve patient factors of HF worsening.

Main results

Funding Acknowledgement

Type of funding source: None

Influence of Self-Esteem and Psychiatric Diagnosis on Health-Related Quality of Life in Children and Adolescents with School Refusal Behavior

BACKGROUND

School refusal behavior (SRB), which is the refusal to attend or remain in school, has been associated with emotional, psychological, and other behavioral problems, as well as a lower health-related quality of life (HRQOL). However, the effects of self-esteem and a psychiatric diagnosis in students with SRB on HRQOL are not yet known. Understanding these relationships could help to develop more effective therapeutic interventions.

METHODS

A total of 175 young people (aged 8-18 years old) who visited our medical centers and outpatient clinics participated in the study. This comprised the SRB group (n = 70) and an age- and sex-matched control group (n = 105). Information about any psychiatric diagnosis was collected from medical records, HRQOL was measured using the J-KIDSCREEN-52, SRB was assessed using the School Refusal Assessment Scale-Revised for Japanese Attendance at School, self-esteem was measured using the Rosenberg Self-Esteem Scale, children's mental health status was measured using the Strengths and Difficulties Questionnaire, and social support was measured using the Oslo 3-item Social Support Scale. We performed between-group comparisons and multiple regression analysis.

RESULTS

The SRB had a significantly lower HRQOL than the control group in several of the KIDSCREEN-52 dimensions. In the SRB group, 35.7% had chronic disease and 35.7% of their parents had health problems and were receiving treatment. The multiple regression analysis revealed that, within the SRB group, a psychiatric diagnosis was associated with a lower HRQOL. However, this was not the case for a diagnosis of autistic spectrum disorder. Self-esteem positively affected HRQOL in six dimensions of the KIDSCREEN-52 within the SRB group.

CONCLUSION

Our results could inform the development of support strategies for young people with SRB. Namely, support that enhances self-esteem could be used to increase HRQOL in young people with SRB. Furthermore, the presence of psychiatric disorders should be assessed as early as possible.

P3827Low dose of quinidine is effective to normalize the slow inactivation in mutant Kv4.3 channel identified in an early repolarization syndrome patient

Background

Early repolarization syndrome (ERS) is characterized by J-point elevation in the ECG and ventricular fibrillation (VF). Several mutations in genes encoding cardiac ion channels have been reported as the causes for ERS. For the treatment of ERS, clinical studies have shown that quinidine is effective for the suppression of electrical storm. However, the mechanism or the optimal concentration for quinidine to suppress the electrical storm has not been elucidated yet.

Purpose

The aim of the present study is to clarify pharmacological effect of quinidine on mutant Kv4.3 channel by electrophysiological analysis and to establish theoretically effective treatment for ERS.

Methods

A KCND3 mutation, p.G306A, identified heterozygously in a 12-year-old boy was examined by whole-cell patch-clamp methods using CHO cells. We performed functional analysis of the Kv4.3 channels encoded by KCND3 of wild-type (WT), heterozygous (WT/G306A), or homozygous (G306A) mutants. Pharmacological normalizing effects of quinidine to the WT and mutant channels were investigated by loading test in various concentration. The sensitivity of quinidine was evaluated in terms of the concentration of the clinical course and the loading test.

Results

The patient suffered VF while sleeping or under sedation. Significant J-point elevations in multiple leads were recorded and he was diagnosed as ERS. Quinidine administration in the serum concentration of 1.2 to 3.1 μM was effective to stop his VF storm. Mutant Kv4.3 currents showed significantly slow inactivation time course (Fig 1), which meant that the mutation caused the gain-of-function channel. Quinidine loading to the mutant Kv4.3 normalized the inactivation time course in concentration-dependent manner (Fig 2, 3). In the loading concentration of 1 μM, the peak currents were not changed regardless of the voltage (Fig 4). The optimal serum concentration of quinidine in clinical use as multi-ion-channels blocker is 6 to 15 μM and the concentration was higher than that of the patient to stop the VF storm. The electrophysiological analysis showed that the low dose loading of quinidine was effective to prevent the gain-of function change of mutant Kv4.3 channels.

Electrophysiological analysis

Conclusions

We showed the pharmacological mechanism of quinidine against the mutant Kv4.3 channels identified in an ERS patient. Even the low concentration of quinidine was effective to normalize the slow inactivation, gain-of-function, in mutant Kv4.3 channels. Our data would be helpful to confirm the optimal concentration of quinidine for ERS patients to avoid adverse effect.

P2560Metalloprotease nardilysin controls heart rate through the transcriptional regulation of ion channels critical for sinus automaticity

Acknowledgement/Funding

KAKENHI (17K09575)

Pubertal Development and Pregnancy Outcomes in 46,XX Patients With Nonclassic Lipoid Congenital Adrenal Hyperplasia

CONTEXT

Lipoid congenital adrenal hyperplasia (LCAH) is characterized by a disorder of steroidogenesis in both adrenal glands and gonads. 46,XX patients with classic LCAH usually have thelarche and menarche but show anovulatory menstruations and subsequent premature menopause. Only three patients with classic LCAH have been reported to successfully achieve delivery with the aid of assisted reproductive therapies for conception and progesterone replacement therapy during early pregnancy. In contrast, pubertal development and pregnancy outcomes in patients with nonclassic LCAH have not been fully elucidated.

CASE DESCRIPTION

We report four Japanese women who had a diagnosis of primary adrenal insufficiency during infancy or childhood and carried compound heterozygous STAR mutations (p.Gln258* and p.Arg188His, p.Gln258* and p.Met225Thr, and p.Gln258* and p.Arg272Cys). In all four patients, thelarche and menarche spontaneously occurred from 10 to 11 years of age and from 12 to 14 years of age, respectively. Subsequently, their menstruation cycles were regular at almost 1-month intervals. Patient 1 conceived naturally twice, and patient 2 conceived with the use of clomiphene citrate for ovulation induction. These two patients maintained the pregnancies without progesterone replacement therapy and successfully delivered children.

CONCLUSION

Patients with nonclassic LCAH maintain ovarian function, which enables normal pubertal development and a successful pregnancy outcome without progesterone replacement therapy.