Usefulness of echocardiographic parameters in predicting the incidence of ischemic stroke in Japanese patients with non-valvular atrial fibrillation

Background

Atrial fibrillation (AF) is a risk factor for ischemic stroke (IS). We developed a novel risk score of IS (HELT-E2S2 score) in non-valvular atrial fibrillation (NVAF) patients from the combined database of 5 major AF registries in Japan. However, this score does not include echocardiographic (Echo) parameters that have been reported to be risk factors of IS, such as left atrial diameter (LAD) enlargement or increased relative wall thickness (RWT) of left ventricle (LV).

Purpose

To investigate the predictive value of Echo parameters in Japanese patients with NVAF.

Methods

After excluding patients without the Echo data, 6,032 NVAF patients were analyzed in the present study. LAD was measured in the parasternal long axis view at the end-ventricular systole. RWT was calculated as (2x posterior wall thickness)/ LV end-diastolic dimension. We compared clinical characteristics and the incidence of IS between NVAF patients divided by LAD level (High/Low LAD group) and RWT level (High/Low RWT group). To balance the follow-up period among the registries, event data from individuals whose follow-up period exceeded 730 days were excluded from the analysis.

Results

The optimal cut-off value of LAD and RWT to predict the incidence of IS with the receiver operating characteristic analysis was 43.3 mm and 0.4167, respectively. Between the High/Low LAD groups (High LAD: n=2,640 vs. Low LAD: n=3,392), age (70.3±12.1 vs. 68.3±12.5 years; p<0.001), CHA2DS2-VASc score (3.02±1.84 vs. 2.57±1.78; p<0.001), HELT-E2S2 score (2.20±1.31 vs. 1.55±1.33; p<0.001), the prescription of oral anticoagulants (OACs) (69.5 vs. 51.5%; p<0.001), LV ejection fraction (60.4±13.4 vs. 64.4±10.7%; p<0.001) and RWT (0.401±0.091 vs. 0.396±0.082; p=0.02) were significantly different. Between the High/Low RWT groups (High RWT: n=2,293 vs. Low RWT: n=3,739), percentage of female (35.6 vs. 27.8%; p<0.001), age (71.2±12.1 vs. 68.0±12.4 years; p<0.001), CHA2DS2-VASc score (3.08±1.82 vs. 2.58±1.79; p<0.001), HELT-E2S2 score (2.10±1.39 vs. 1.67±1.31; p<0.001), the prescription of OACs (62.6 vs. 57.4%; p<0.001), LV ejection fraction (65.5±9.9 vs. 60.9±13.0%; p<0.001) and LAD (43.0±8.1 vs. 42.4±8.3; p=0.004) were significantly different. In Kaplan-Meier analysis, the incidence of IS was different between the groups during the median follow-up period of 730 days (High LAD vs. Low LAD; 1.82 vs. 1.00 per 100 person-years; p<0.001, by log-rank test, High RWT vs. Low RWT; 1.86 vs. 1.06; p<0.001) (Figure). Both High LAD (hazard ratio: 1.65, 95% CI: 1.12–2.46; p=0.01) and High RWT (hazard ratio: 1.43, 95% CI: 1.01–2.04; p=0.045) were independent predictors of the incidence of IS after adjustment by the components of the HELT-E2S2 score and other clinically relevant variables including co-existing diseases, gender, and the prescription of OACs (Table).

Conclusion

Echo parameters, LAD and RWT, were independently associated with the incidence of IS among Japanese patients with NVAF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development

Mortality and 30-day readmission rate following leadless pacemaker implantation: insights from the Nationwide Readmissions Database

Background

Clinical trials and registry data showed encouraging outcomes for leadless pacemaker (LP) implantation. However, reports of patient characteristics, trends, and clinical outcomes in a real-world population are limited.

Purpose

To provide real-world evidence of the rates, trends, and patient characteristics associated with in-hospital complications and 30-days readmission after LP implantations.

Methods

Using the all-payer, nationally representative Nationwide Readmissions Database between 2017 and 2019, we analyzed leadless or conventional pacemaker implantations. The national trends of in-hospital mortality, in-hospital complication rates and 30-day readmission rates after pacemaker implantation and their national trends were analyzed. Mixed-effects multivariable logistic regression analysis was performed to identify factors associated with in-hospital death and 30-days readmission in LP patients.

Results

A total of 137,732 admissions (age: 78 [70–85], 5,986 LP implantations) were analyzed (Figure 1). The in-hospital mortality, overall in-hospital complication rate, and 30-days readmission rates after LP implantations were 5.0%, 16%, and 16%, respectively. In LP recipients, the national estimate of in-hospital mortality declined from 10.9% in the second quarter of 2017 to 4.3% in the fourth quarter of 2019 (P<0.001) (Figure 2a). Furthermore, the national estimate of overall complication rate declined from 20.6% in the second quarter of 2017 to 13.0% in the fourth quarter of 2019 (P<0.001) (Figure 2b). Conversely, non-elective 30-day readmission rate did not show any increasing or decreasing trends in LP recipients (P=0.74) (Figure 2c). In LP recipients, female sex (odds ratio [OR] 1.42, 95% confidence interval [CI] 1.04–1.93), history of heart failure (OR 2.02, 95% CI 1.46–2.79), and first quartile annual pacemaker implantation hospital volume (OR 2.49, 95% CI 1.56–3.97, fourth quartile annual pacemaker implantation hospital volume used as a reference standard) were factors associated with in-hospital death.

Conclusions

Analysis of the nationally representative claims database in the US showed in-hospital mortality, complication rates, and non-elective 30-day readmission rate of 5.0%, 16%, and 16% respectively, for LP implantation performed during hospitalization. Although in-hospital mortality and complication rates showed a decreasing trend over time, ongoing surveillance is needed for the safety of LP implantation.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Intramural research fund (21-6-9)for cardiovascular diseases of national cerebral and cardiovascular center.

Predictive capability of material screening by fast neutron activation analysis using laser-driven neutron sources

Bright, short-pulsed neutron beams from laser-driven neutron sources (LANSs) provide a new perspective on material screening via fast neutron activation analysis (FNAA). FNAA is a nondestructive technique for determining material elemental composition based on nuclear excitation by fast neutron bombardment and subsequent spectral analysis of prompt γ-rays emitted by the active nuclei. Our recent experiments and simulations have shown that activation analysis can be used in practice with modest neutron fluences on the order of 10⁵ n/cm², which is available with current laser technology. In addition, time-resolved γ-ray measurements combined with picosecond neutron probes from LANSs are effective in mitigating the issue of spectral interference between elements, enabling highly accurate screening of complex samples containing many elements. This paper describes the predictive capability of LANS-based activation analysis based on experimental demonstrations and spectral calculations with Monte Carlo simulations.

Super-strong magnetic field-dominated ion beam dynamics in focusing plasma devices

High energy density physics is the field of physics dedicated to the study of matter and plasmas in extreme conditions of temperature, densities and pressures. It encompasses multiple disciplines such as material science, planetary science, laboratory and astrophysical plasma science. For the latter, high energy density states can be accompanied by extreme radiation environments and super-strong magnetic fields. The creation of high energy density states in the laboratory consists in concentrating/depositing large amounts of energy in a reduced mass, typically solid material sample or dense plasma, over a time shorter than the typical timescales of heat conduction and hydrodynamic expansion. Laser-generated, high current–density ion beams constitute an important tool for the creation of high energy density states in the laboratory. Focusing plasma devices, such as cone-targets are necessary in order to focus and direct these intense beams towards the heating sample or dense plasma, while protecting the proton generation foil from the harsh environments typical of an integrated high-power laser experiment. A full understanding of the ion beam dynamics in focusing devices is therefore necessary in order to properly design and interpret the numerous experiments in the field. In this work, we report a detailed investigation of large-scale, kilojoule-class laser-generated ion beam dynamics in focusing devices and we demonstrate that high-brilliance ion beams compress magnetic fields to amplitudes exceeding tens of kilo-Tesla, which in turn play a dominant role in the focusing process, resulting either in a worsening or enhancement of focusing capabilities depending on the target geometry.

Population-based incidence and outcomes of acute aortic dissection in Japan

Background

The population-based incidence and outcomes of acute aortic dissection (AAD) are still unknown because some patients are already dead on arrival at the hospital, and the accurate diagnosis of AAD is difficult due to the low autopsy rate for patients with cardiopulmonary arrest outside of the hospital. We performed a population-based review of all patients with AAD in a well-defined geographical area in the southern part of Japan between 2016 and 2018.

Methods

Data of all patients with AAD at our Hospital, which performs medical care for 120,000 residents, were collected retrospectively. The emergency medical service is dedicated to the transfer of all patients in this area to the MPNH. For all patients who were dead on arrival, the diagnosis of AAD was made by autopsy imaging (AI) using computed tomography. The age-adjusted incidence and mortality per 100,000 population were calculated using the Japanese population distribution model in 2015.

Results

The total incidence of AAD was 79 (type A: 64.5%, n=51). Of those, 60.8% (31/51) of patients with type A and 21.4% (6/28) with type B were dead on arrival and diagnosed by AI. The 30-day mortality rates after the onset of AAD were 74.5% (38/51) in type A and 25.0% (7/28) in type B. Excluding the dead-on-arrival patients, the 30-day mortality rates were 35.0% (7/20) in type A and 4.5% (1/22) in type B. The age-adjusted incidence and mortality of AAD per 100,000 inhabitants were 17.3 (type A: 11.3, type B: 6.0) and 9.6 (type A: 8.4, type B: 1.2), respectively. Both values were significantly higher in men than in women.

Conclusions

The population-based survey of emergency medical care for AAD showed that the age-adjusted incidence of AAD was two-fold higher than in previous reports, and the actual mortality rates after AAD onset were markedly higher due to the high incidence of dead-on-arrival.

Funding Acknowledgement

Type of funding sources: None. Representative CT images of type A AAD

Dosimetric calibration of GafChromic HD-V2, MD-V3, and EBT3 films for dose ranges up to 100 kGy

A dosimetric calibration of three types of radiochromic films (GafChromic^TM HD-V2, MD-V3, and EBT3) was carried out for absorbed doses (D) ranging up to 100 kGy using a 130 TBq Co60 γ-ray source. The optical densities (ODs) of the irradiated films were acquired with the transmission-mode flatbed film scanner EPSON GT-X980. The calibration data were cross-checked using the 20-MeV proton beam from the azimuthally varying field cyclotron at the Research Center for Nuclear Physics in Osaka University. These experimental results not only present the measurable dose ranges of the films depending on the readout wavelength, but also show consistency with our hypothesis that the OD response curve [log(OD)-log(D) curve] is determined by the volumetric average of the absorption dose and does not strongly depend on the type of radiation for the excitation.

The nationwide registry of hospitalized heart failure patients in Japan: Japanese Registry Of Acute Decompensated Heart Failure (JROADHF)

Background and aim

Heart failure (HF) is a growing healthcare problem worldwide. This study aimed to describe clinical characteristics and long-term outcomes of HF patients in Japan.

Methods and results

JROADHF (the Japanese Registry Of Acute Decompensated Heart Failure) is a retrospective, multicentre, nationwide observational database of 13,238 patients hospitalized due to HF in 128 hospitals randomly selected from Japanese Circulation Society (JCS)-certified teaching hospitals during 2013. At inclusion, demographic and clinical data were collected from medical records with linkage to a nationwide claim-based database, the Japanese Diagnosis Procedure Combination (DPC). Patients were followed up to 5 years after discharge at each participating site. Patients were old as the median age of 81 years and women were older (74.8±12.8 vs 81.6±11.1 y.o). Mean left ventricular ejection fraction (LVEF) was 47%, and 45% were HF with preserved ejection fraction of >50% (HFpEF). Causes of HF included ischemic in 27%, valvular in 19%, arrhythmia in 17%, and hypertensive in 16%. Median length of hospital stay was 18 days and in-hospital mortality was 7.7%. All-cause mortality during 1 and 4 years were 22.3% and 48.4%, respectively. Hospitalization rates due to HF within 1 and 4 years were as high as 30.5 and 48.4%, respectively.

Conclusions

Contemporary nationwide registry revealed that hospitalized HF patients were elder and had more HFpEF, and their prognosis was still poor compared to the data shown in prior registries.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development (AMED) Practical Research Project for Life-Style related Diseases including Cardiovascular Diseases and Diabetes Mellitus

Impact of endovascular repair on the outcomes of octogenarians with ruptured abdominal aortic aneurysms: a nationwide Japanese study

Objective

This study aimed to clarify the impact of endovascular aneurysm repair (EVAR) on clinical outcomes in Japanese patients of advanced age with ruptured abdominal aortic aneurysm (rAAA).

Methods

This was a national registry based retrospective comparative study, using data from the Japanese Registry Of All cardiac and vascular Diseases-Diagnostic Procedure Combination (JROAD-DPC), a nationwide claim based database from more than 600 hospitals. Patients admitted with rAAA between April 1, 2012, and March 31, 2015 were included in the study. Patient characteristics, management, and outcomes were compared between the elderly (aged ≥80 y) and the less old. The primary endpoint was in hospital mortality; the secondary endpoint was the functional status at discharge.

Results

Of 3 969 eligible patients, 49.9% were categorised as elderly. Elderly patients had a higher prevalence of female gender (41.8% vs. 17.0%, p<0.001) and disturbance of consciousness on admission (28.6% vs. 20.7%, p<0.001). They were less likely to undergo open surgical repair (31.6% vs. 56.7%, p<0.001), although EVAR was performed similarly in both groups (13.7% vs. 14.8%, p<0.33). The unadjusted mortality rate (61.8% vs. 37.6%, p<0.001) and mean Barthel index at discharge (73.0 vs. 91.8, p<0.001) were statistically significantly worse in the elderly. Multilevel mixed effect logistic regression analyses showed that old age was detected as an independent predictor of in hospital death (odds ratio 2.75; 95% confidence interval, 2.39–3.17; p<0.001). However, for patients who received EVAR, old age was not statistically significant (odds ratio 1.13; 95% confidence interval, 0.77–1.66; p<0.53).

Conclusion

Elderly patients with rAAA were less likely to be offered open surgical repair, and the mortality among those who received surgery was high. However, for the small subgroup of elderly patients currently selected for EVAR there was a favourable outcome. The further implementation of EVAR for rAAA in Japan, especially for elderly patients with suitable anatomy, may be justified.

Funding Acknowledgement

Type of funding source: None

The safety of catheter ablation of atrial fibrillation in elderly patients -analysis of the nationwide database in Japan, JROAD-DPC-

Background

“Age” is one of the major concerns and determinants of the indications for catheter ablation (CA) of atrial fibrillation (AF). There are little safety data on CA of AF according to the age. This study aimed to assess the safety of CA in elderly patients undergoing CA of AF.

Methods and results

We investigated the complication rate of CA of AF for the different age groups (<60 years, 60–65, 65–70, 70–75, 75–80, 80–85, and ≥85) by a nationwide database (Japanese Registry Of All cardiac and vascular Diseases [JROAD]-DPC). The JROAD-DPC included 73,296 patients (65±11 years, 52,883 men) who underwent CA of AF from 516 hospitals in Japan. Aged patients had more comorbidities and a significantly increased CHADS2 score and higher rate of female according to a higher age. The overall complication rate was 2.6% and in-hospital mortality was 0.05%. By comparing each age group, complications occurred more frequently in higher aged groups. A multivariate adjusted hazard ratio revealed an increased age was independently and significantly associated with the overall complications (odds ratio was 1.25, 1.35, 1.72, 1.86, 2.76 and 3.13 respectively; reference <60 years).

Conclusions

The frequency of complications was significantly higher according to a higher age. We should take note of the indications and procedure for CA of AF in aged patients.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Intramural Research Fund 17 (Kusano) for Cardiovascular Diseases of the National Cerebral and Cardiovascular Center

Relativistic magnetic reconnection in laser laboratory for testing an emission mechanism of hard-state black hole system

Magnetic reconnection in a relativistic electron magnetization regime was observed in a laboratory plasma produced by a high-intensity, large energy, picoseconds laser pulse. Magnetic reconnection conditions realized with a laser-driven several kilotesla magnetic field is comparable to that in the accretion disk corona of black hole systems, i.e., Cygnus X-1. We observed particle energy distributions of reconnection outflow jets, which possess a power-law component in a high-energy range. The hardness of the observed spectra could explain the hard-state x-ray emission from accreting black hole systems.

Sesamin suppresses aging phenotypes in adult muscular and nervous systems and intestines in a Drosophila senescence-accelerated model

OBJECTIVE

Sesamin is a major lignan constituent of sesame and possesses various health-promoting effects. Previous studies have demonstrated that sesamin extends the lifespan of Drosophila and Caenorhabditis elegans and corrects oxidative damage-related tissue dysfunction in mammals. To understand its anti-aging effects, we aimed to determine whether sesamin restores tissue function hampered by oxidative damage and suppresses several aging-related phenotypes using Drosophila senescence-accelerated models.

MATERIALS AND METHODS

We elucidated the anti-aging effects of sesamin on several aging-related phenotypes in the muscle, brain and midgut using the senescence-accelerated models (Sod1n1 mutant and Sod1-depleted flies) by immunostaining experiments. We determined the expression levels of several anti-oxidative and DNA repair genes using quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). We also identified the metabolite of sesamin in Drosophila by LC-MS/MS.

RESULTS

We confirmed that sesamin (0.35 and 2 mg/ml) extended the lifespan of the fly models. As observed in mammals, it can be absorbed and metabolized by Drosophila adults. The sesamin feeding suppressed the age-dependent impairment of locomotor activity and inhibited the accumulation of reactive oxygen species (ROS) in their bodies. Sesamin delayed the age-dependent accumulation of damaged proteins in the muscle, partially suppressed the loss of dopaminergic neurons in adult brains displaying ROS accumulation, and suppressed the accumulation of DNA damage and hyperproliferation of intestinal stem cells. Four antioxidative genes and two DNA repair genes were simultaneously upregulated in sesamin-fed adults.  CONCLUSIONS: These observations represent the first direct evidence of the anti-aging effects of sesamin at the individual level. We propose that sesamin exerts anti-aging effects in the muscles, brain and midgut by inducing antioxidative and DNA repair genes, resulting in extended lifespan in flies.

Production of relativistic electrons at subrelativistic laser intensities

Relativistic electron temperatures were measured from kilojoule, subrelativistic laser-plasma interactions. Experiments show an order of magnitude higher temperatures than expected from a ponderomotive scaling, where temperatures of up to 2.2 MeV were generated using an intensity of 1×10^{18}W/cm^{2}. Two-dimensional particle-in-cell simulations suggest that electrons gain superponderomotive energies by stochastic acceleration as they sample a large area of rapidly changing laser phase. We demonstrate that such high temperatures are possible from subrelativistic intensities by using lasers with long pulse durations and large spatial scales.

P3755Left atrial enlargement as an independent risk factor for ischemic stroke in Japanese atrial fibrillation patients: pooled analysis of five major Japanese atrial fibrillation registries

Background

Atrial fibrillation (AF) increases the risk of ischemic stroke. It remains unknown whether left atrial diameter determined by routine trans-thoracic echocardiography is a risk factor for ischemic stroke in non-valvular AF (NVAF) patients.

Purpose

The aim of this study is to investigate the impact of left atrial enlargement (LAE) on the incidence of ischemic stroke in a large-scale cohort of Japanese NVAF patients.

Methods

We combined the data of 5 major AF registries in Japan, J-RHYTHM Registry, Fushimi AF Registry, Shinken Database, Keio interhospital Cardiovascular Studies, and Hokuriku AF Registry. After excluding patients without echocardiographic data, 7,672 NVAF patients were analyzed in the present study (mean age, 69.3±12.3 years; mean CHADS2 score, 1.6±1.3). We compared clinical characteristics and the incidence of ischemic stroke between NVAF patients with LAE (left atrial diameter >45 mm; LAE group) and those without (non-LAE group).

Results

The mean left atrial diameter was 43.1±8.6 mm, and the LAE group accounted for 40.0% (n=3,066) of the entire cohort. Compared with non-LAE group (60.0%, n=4,606), the LAE group was older (LAE vs. non-LAE; 70.3±12.0 vs. 68.0±12.5, p<0.01), more often non-paroxysmal type (73.7% vs. 32.1%, p<0.01), had higher CHADS2 (1.86±1.34 vs. 1.46±1.29, p<0.01) and CHA2DS2-VASc (3.02±1.83 vs. 2.53±1.78, p<0.01) scores, and more frequently received oral anticoagulant (72.9% vs. 55.0%, p<0.01).

During the median follow-up period of 774.5 days (interquartile range: 567–1466 days), ischemic stroke occurred in 241 patients (131 vs. 110 patients; 1.52 vs. 0.82 per 100 person-years). In Kaplan Meier analysis, LAE was associated with a higher incidence of ischemic stroke (unadjusted hazard ratio (HR): 1.83, 95% confidence interval (CI): 1.42–2.36; log rank p<0.01) (Figure). LAE was independently associated with increased risk of ischemic stroke (adjusted HR: 1.63, 95% CI: 1.25–2.11; p<0.01) after adjustment by the components of CHADS2 score and the use of oral anticoagulant, on multivariate Cox proportional hazard analysis.

Conclusion

In this large-scale cohort of Japanese patients with AF, LAE was an independent predictor of ischemic stroke, suggesting that this simple echocardiographic parameter could refine thromboembolic risk stratification of NVAF patients.

Acknowledgement/Funding

Japan Agency for Medical Research and Development, AMED

P5599Prognostic impact of quality indicators on outcomes of acute aortic dissection in Japan

Background

Despite recent advances in diagnosis and management, the mortality of acute aortic dissection (AAD) remains high.

Purpose

This study aims to develop quality indicators (QIs) for the management of AAD, and to evaluate the associations between QIs and outcomes of AAD in a Japanese nationwide administrative database.

Methods

A total of 18,348 patients suffered from AAD (Type A: 10,131, Type B: 8,217) in the Japanese Registry of All Cardiac and Vascular Diseases database between 2012 and 2015 were studied. A systematic review was performed to establish initial index items for QIs. Evaluation was performed through the expert consensus meeting using a Delphi method. Associations between developed QIs and the mortality were determined by multivariate mixed logistic regression analyses.

Results

A total of nine QIs (five structural and four processatic) were developed. Achievements of developed QIs (High: 7–9, Middle: 4–6, Low: 0–3) were significantly associated with lower in-hospital mortality even after adjustment for covariates in both type A (Middle: odds ratio [OR], 0.257; 95% confidence interval [CI], 0.211–0.312; P<0.001; High: OR, 0.064; 95% CI, 0.047–0.086; P<0.001 vs. Low) and type B (Middle: OR, 0.447; 95% CI, 0.338–0.590; P<0.001; High: OR, 0.128; 95% CI, 0.077–0.215; P<0.001 vs. Low). Additionally, achievements of structural and processatic QIs were consistently associated with reduced in-hospital mortality.

QIs and in-hospital mortality

Conclusions

Developed QIs for AAD management were significantly associated with lower in-hospital mortality. Evaluation of each hospital's management with QIs could be helpful to equalize quality of treatment and to fill the evidence-to-practice gaps in the real-world treatment.

6131Association between hospital care quality and readmission among Japanese patients with heart failure. From JROAD-DPC study

Background

Measuring the process of care has become a widely used practice to improve a quality of care. Recently, some studies have demonstrated poor to no correlation between 30-day readmission rates and quality of care for heart failure (HF) among hospitalized HF patients. However the investigation about relationships of care quality for HF and 1 year outcome is limited.

Purpose

To investigate the relationship between quality of care in each hospitals and readmission among HF patients in Japan.

Methods

From Japanese Registry of All cardiac and vascular diseases (JROAD-DPC) database in 2014, 84,325 HF patients hospitalized to 741 certificated hospitals by Japanese Circulation Society were analyzed. A primary endpoint was readmission for HF in one year. Five performance measures were defined as prescription rate of angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEI/ARB), prescription rate of beta blocker and prescription rate of spironolactone, measurement rate of echocardiography and measurement rate of B-type natriuretic peptide (BNP) during hospitalization. For each of the five measures, a composite score was created by giving points ranging from 1 to 4 from the lower quartile of rates, with the score ranging from 5 to 20 points. Hazard ratios (HR) indicating the effects of the performance measures were estimated using Cox proportional hazard models. Covariates included age, gender, Charson score, and NYHA class.

Results

In Japanese HF patients (age; 78.1 years old, man 52%), the HF readmission rate in one year was 14,520 (17.2%). The readmission rate decreased with higher quartiles of prescription rate in each medications and performance rates. The highest quartile of each measurements was significantly lower risk for readmission compared to the lowest quartile (ACE/ARB, adjusted HR 0.87 [95% CI, 0.83–0.91], p<0.001; beta-blocker, 0.83 [0.79–0.88], p<0.001; spironolactone, 0.88 [0.83–0.92], p<0.001; echocardiography, 0.90 [0.86–0.94], p<0.001; BNP, 0.92 [0.87–0.96], p<0.001). Kaplan-Meier curves showed that readmission rates were better among higher composite score, compared to lower composite score (Log-rank test=p<0.001). (Figure) Higher composite scores were associated with statistically significant risk reduction of 23% for HF readmission (HR 0.77, 95% CI [0.73–0.81], p<0.001).

Figure 1

Conclusion

The hospital performance measures were associated with a significant risk reduction of readmission in Japanese patients with HF.

P5605The impact of institutional case volume on the Ppognosis of ruptured aortic aneurysms: a Japanese nationwide study

Background

To improve outcome for ruptured aortic aneurysms (rAA), centralization of treatment is potentially effective. However, there is no nationwide survey for the current managements and outcomes of rAA in Japan.

Purpose

The aim of this study was to assess the volume-outcome relationship for rAA treatment using the nationwide claim-based database.

Methods

Using the Japanese Registry Of All cardiac and vascular Diseases- Diagnostic Procedure Combination database, we identified patients admitted to 564 certified teaching-hospitals with rAA between April 1, 2012 and March 31, 2015. Institutional case volume (cardiovascular surgeries per year) was categorized into quartiles (Lowest, Low, High, and Highest) and the odds ratios (ORs) for in-hospital mortality and neurological status at discharge were analyzed for each quartile.

Results

Of 7086 eligible patients, 3925 (55.4%) died in hospital. Mortality rates decreased from 69.4% in the lowest-volume to 43.8% in the highest-volume category (P<0.001). The favourable impact of institutional case volume was sustained even after adjustment for covariates (Low-volume: OR, 0.83; 95% confidence interval [CI], 0.65–1.07; P=0.147; High-volume: OR, 0.69; 95% CI, 0.54–0.89; P=0.005; and Highest-volume: OR, 0.55; 95% CI, 0.42–0.72; P<0.001 vs. Lowest-volume). Additionally, other three institutional parameters (increased aortic surgery volume, cardiovascular surgeons' volume, and certified cardiologists' volume) were consistently associated with reduced in-hospital mortality. The rate of coma at discharge was the lowest in the Highest-volume group (P<0.001).

Institutional volume and mortality

Conclusions

Increased institutional volume was associated with lower in-hospital mortality. Establishing regionally tailored systems to transfer patients to high-volume centers is needed to improve outcomes.

P884Short-term exposure to asian dust is associated with myocardial infarction with nonobstructive coronary arteries

Background

Asian dust (AD) is considered as one of air pollution that increases risk of acute myocardial infarction (AMI). However, it has not been elucidated whether AD might increase the risk of myocardial infarction with nonobstructive coronary arteries (MINOCA).

Methods

A time-stratified case-crossover design and conditional logistic regression models was used to investigate the association between short-term exposure to AD and admission of AMI during the spring months in a nationwide administrative Diagnostic Procedure Combination (DPC) database, the Japanese Of All cardiac and vascular Diseases (JROAD)-DPC, between April 2012 through March 2016. MINOCA was defined as AMI having angiography without revascularization and coronary atherosclerosis, whereas myocardial infarction with obstructive coronary artery disease (MI-CAD) was AMI with revascularization and/or coronary atherosclerosis. Data for AD events, air pollutants (PM2.5, Ox, NO2, SO2), and meteorological variables were obtained from the nearest monitoring station of the hospital.

Results

During the study period, 3,233 MINOCA and 27,202 MI-CAD patients were identified from 30,435 AMI patients. Although the occurrence of AD events 2 days before the admission was not associated with the admission of AMI and MI-CAD, the AD events was significantly associated with the admission of MINOCA with adjustment for meteorological variables and each air pollutant. In subgroup analysis of MINOCA, patients without low ADL was associated with higher risk of the admission due to AD exposure than those with low ADL, with significant interaction.

Conclusions

AD events might be more likely to trigger onset of MINOCA than MI-CAD.

Acknowledgement/Funding

None

Enhancing laser beam performance by interfering intense laser beamlets

Increasing the laser energy absorption into energetic particle beams represents a longstanding quest in intense laser-plasma physics. During the interaction with matter, part of the laser energy is converted into relativistic electron beams, which are the origin of secondary sources of energetic ions, γ-rays and neutrons. Here we experimentally demonstrate that using multiple coherent laser beamlets spatially and temporally overlapped, thus producing an interference pattern in the laser focus, significantly improves the laser energy conversion efficiency into hot electrons, compared to one beam with the same energy and nominal intensity as the four beamlets combined. Two-dimensional particle-in-cell simulations support the experimental results, suggesting that beamlet interference pattern induces a periodical shaping of the critical density, ultimately playing a key-role in enhancing the laser-to-electron energy conversion efficiency. This method is rather insensitive to laser pulse contrast and duration, making this approach robust and suitable to many existing facilities.

Enhanced coupling of laser energy to the target particles is a fundamental issue in laser-plasma interactions. Here the authors demonstrate increased photon absorption leading into higher laser to electron and proton energy transfer through the interference of multiple coherent beamlets.

Association between Sarcopenia and Overactive Bladder in Elderly Diabetic Patients

OBJECTIVES

To determine the association between sarcopenia and overactive bladder (OAB) in elderly diabetic patients using the Japanese version of SARC-F called SARC-F-J.

DESIGN

Cross-sectional study.

SETTINGS AND PARTICIPANTS

The study included 329 elderly diabetic patients (aged ≥65 years) who regularly visited the outpatient clinic at Community hospital in Japan.

MEASUREMENTS

The condition of OAB was evaluated using the OAM symptom score, which involves a self-administered questionnaire, and sarcopenia was evaluated using the self-administered SARC-F-J questionnaire comprising five items. The odds ratio for OAB due to sarcopenia was calculated using multiple logistic regression analysis, with OAB as the dependent variable and sarcopenia as the explanatory variable.

RESULTS

A total of 329 patients (186 males, 143 females) were included for analysis in the present study. Of these patients, 22.9% had sarcopenia and 18.7% had OAB. After adjusting the variables, the odds ratio for OAB due to sarcopenia was 4.46 (95% confidence interval [CI], 1.14-17.36, P = 0.031) and 2.09 (95% CI, 0.52-8.26, P = 0.293) for males and females, respectively.

CONCLUSION

This study found that sarcopenia was significantly associated with OAB in elderly diabetic male patients based on SARC-F-J. Moreover, the possibility of the development of OAB should be considered during the medical examinations of elderly diabetic male patients with sarcopenia.

Plasma natriuretic peptide levels in fetuses with congenital heart defect and/or arrhythmia

OBJECTIVE

Diagnosing fetal heart failure remains challenging because it is difficult to know how well the fetal myocardium will perform as loading conditions change. In adult cardiology, natriuretic peptides (NPs) are established markers of heart failure. However, the number of studies investigating NP levels in fetuses is quite limited. The aim of this study was to evaluate the significance of plasma NP levels in the assessment of heart failure in fetuses with a congenital heart defect (CHD) and/or arrhythmia.

METHODS

This was a prospective observational study conducted at a tertiary pediatric cardiac center. A total of 129 singletons with CHD and/or arrhythmia and 127 controls were analyzed between 2012 and 2015. Umbilical cord plasma atrial NP, brain NP and N-terminal pro-brain NP levels at birth were compared with ultrasonography findings indicating fetal heart failure, such as cardiovascular profile (CVP) score and morphological characteristics.

RESULTS

Fetuses with CHD and/or arrhythmia had higher NP levels than did controls (P < 0.01). NP levels of fetuses with CHD and/or arrhythmia were correlated inversely with CVP score (P for trend < 0.01). No differences in NP levels were found in fetuses with CHD and/or arrhythmia and a CVP score of ≥ 8 in comparison to controls. Multivariate analysis showed that a CVP score of ≤ 5, tachy- or bradyarrhythmia at birth, preterm birth and umbilical artery pH < 7.15 were associated independently with high NP levels (P < 0.01). Among fetuses with a CVP score of ≤ 7, abnormal venous Doppler sonography findings were significantly more common and more severe in fetuses with tachy- or bradyarrhythmia than in those with CHD, and those with tachy- or bradyarrhythmia had higher NP levels than did those with CHD (P = 0.01). Fetuses with right-heart defect and moderate or severe tricuspid valve regurgitation had significantly higher NP levels than did fetuses with other types of CHD (P < 0.01).

CONCLUSIONS

Plasma NP levels in fetuses with CHD and/or arrhythmia are correlated with the severity of fetal heart failure. Elevated NP levels are attributed mainly to an increase in central venous pressure secondary to arrhythmia or atrioventricular valve regurgitation due to CHD, rather than to the morphological abnormality itself. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

A multichannel gated neutron detector with reduced afterpulse for low-yield neutron measurements in intense hard X-ray backgrounds

A design of multichannel gated photomultiplier tube (PMT) is presented for the 960-channel neutron time-of-flight detector at the Institute of Laser Engineering of Osaka University. This is important for the fusion science and the nuclear photonics where intense hard X-rays are generated from the interaction of ultra-short laser pulse of petawatt power density with matter. The hard X-rays often overload PMTs and cause signal-induced background noises called afterpulses, making the detection of subsequent neutrons impossible. For this reason, the PMTs are coupled with an electrical time-gating (ETG) system to avoid overloading. The ETG system disables the PMT by modulating the dynode potential during the primary X-ray flash. An after-pulsing suppression technique is demonstrated by applying a reverse bias voltage between the photocathode and the first dynode. The presented multichannel scheme provides a gate response time of 80 ns, a signal cutoff ratio of 2.5 × 10², and requires reasonably low power consumption.

A large-aperture high-sensitivity avalanche image intensifier panel

A large-aperture high-sensitivity image intensifier panel that consists of an avalanche photodiode array and a light-emitting diode array is presented. The device has 40% quantum efficiency, over 10⁴ optical gain, and 80-ns time resolution. The aperture size of the device is 20 cm, and with the current manufacturing process, it can be scaled to arbitrarily larger sizes. The device can intensify the light from a single particle scintillation emission to an eye-visible bright flash. The image resolution of the device is currently limited by the size of the avalanche photodiode that is 2 mm, although it can be scaled to smaller sizes in the near future. The image intensifier is operated at a small voltage, typically +57 V. The device can be applied to various applications, such as scintillation imaging, night vision cameras, and an image converter from non-visible light (such as infrared or ultraviolet) to visible light.

Comparing the risk of hepatitis B virus reactivation between direct-acting antiviral therapies and interferon-based therapies for hepatitis C

Hepatitis B virus (HBV) reactivation has been reported during antihepatitis C treatment in patients with hepatitis C virus (HCV) and HBV co-infection. We aimed to evaluate the frequency and risk factors of HBV reactivation during anti-HCV therapy and compared those between interferon (IFN)-free direct-acting antiviral (DAA) therapies and IFN-based therapies. Three hundred and twenty-two patients with HCV infection receiving anti-HCV therapy were retrospectively screened. The baseline HBV infection statuses of all eligible patients and the HBV-DNA level of all patients with current or previous HBV infection were examined at the end of treatment. In patients with baseline anti-HBs positivity, changes in anti-HBs titre were evaluated. Of 287 patients who met the inclusion criteria, 157 had current (n=4) or previous (n=153) HBV infection; 85 were treated with IFN-free DAA therapies and 72 were treated with IFN-based therapies. Six patients experienced HBV reactivation (n=2) or HBV reappearance (n=4) after IFN-free DAA therapies, while no patient developed HBV reactivation after IFN-based therapies. The risk factors of HBV reactivation or reappearance were DAA therapies and a reduction in anti-HBs titre to <12 mIU mL^-1 by the end of treatment. The decline changes of anti-HBs titre were significantly higher in patients treated with DAA therapies. Although HBV reactivation hepatitis was not observed, three of four patients with HBV reactivation or reappearance after achieving HCV eradication had viremia 8 weeks after completion of therapy. A significant proportion of patients develop HBV reactivation or reappearance without hepatitis after IFN-free DAA therapies. Low levels of anti-HBs and their decrease to <12 mIU mL^-1 after treatment are significant risk factors for HBV reactivation or reappearance.

Metastable Zr-Nb alloys for spinal fixation rods with tunable Young's modulus and low magnetic resonance susceptibility

Good ductility, low magnetic susceptibility, and tunable Young's modulus are highly desirable properties for materials usage as spinal fixation rods. In this study, the effects of niobium content on the microstructure, magnetic susceptibility, and mechanical properties of Zr-xNb (13≤x≤23wt%) alloys were investigated. For the Zr-15Nb and Zr-17Nb alloys, a remarkable increase in Young's modulus was achieved due to the occurrence of deformation-induced ω phase transformation. This was the result of the competition of two factors associated with the Nb content: an increase of the stability of β phase and a decrease of the amount of athermal ω phase with increasing Nb content. When the Nb content was 15% or 17%, the amount of deformation-induced ω phase was maximum. Moreover, the magnetic susceptibility decreased with the deformation-induced β→ω phase transformation, and the Zr-17Nb alloy with apparent kink bands exhibited a smaller amount of springback than the Zr-15Nb alloy with {332} 〈113〉 mechanical twins. Furthermore, the ions released from the Zr-xNb alloys in accelerated immersion tests were at a very low level. The combination of low initial Young's modulus, and its remarkable variation induced by deformation, low magnetic susceptibility, good ductility, and smaller springback make the Zr-17Nb alloy a potential candidate for spinal fixation rods.

STATEMENT OF SIGNIFICANCE

For the rods of spinal fixation devices, it is important but difficult to lower the springback for bending formativeness while keeping the low initial Young's modulus for biocompatibility and lower the magnetic susceptibility for postoperative examination simultaneously. In this study, Zr-17Nb alloy was successfully developed via deformation-induced ω phase transformation during loading, simultaneously meeting the abovementioned properties for spinal fixation rods.

Assessing infrared intensity using the evaporation rate of liquid hydrogen inside a cryogenic integrating sphere for laser fusion targets

Infrared (IR) heating processes have been studied to form a deuterium layer in an inertial confinement fusion target. To understand the relationship between the IR intensity and the fuel layering time constant, we have developed a new method to assess the IR intensity during irradiation. In our method, a glass flask acting as a dummy target is filled with liquid hydrogen (LH₂) and is then irradiated with 2-μm light. The IR intensity is subsequently calculated from the time constant of the LH₂ evaporation rate. Although LH₂ evaporation is also caused by the heat inflow from the surroundings and by the background heat, the evaporation rate due to IR heating can be accurately determined by acquiring the time constant with and without irradiation. The experimentally measured IR intensity is 0.66 mW/cm², which agrees well with a value estimated by considering the IR photon energy balance. Our results suggest that the present method can be used to measure the IR intensity inside a cryogenic system during IR irradiation of laser fusion targets.

Boosting laser-ion acceleration with multi-picosecond pulses

Using one of the world most powerful laser facility, we demonstrate for the first time that high-contrast multi-picosecond pulses are advantageous for proton acceleration. By extending the pulse duration from 1.5 to 6 ps with fixed laser intensity of 1018 W cm-2, the maximum proton energy is improved more than twice (from 13 to 33 MeV). At the same time, laser-energy conversion efficiency into the MeV protons is enhanced with an order of magnitude, achieving 5% for protons above 6 MeV with the 6 ps pulse duration. The proton energies observed are discussed using a plasma expansion model newly developed that takes the electron temperature evolution beyond the ponderomotive energy in the over picoseconds interaction into account. The present results are quite encouraging for realizing ion-driven fast ignition and novel ion beamlines.