[Pathophysiology of skeletal muscle during sepsis]

While sepsis mortality is reducing in developed countries due to advances in intensive care medicine, morbidity is increasing due to aging and obesity. ICU-acquired weakness (ICU-AW) is a respiratory and limb muscle weakness experienced by many sepsis survivors and is present in 50-75% of sepsis patients. ICU-AW can persist for several years, making reintegration of sepsis survivors difficult and leading to a secondary decrease in long-term survival. Exposure of septic patients to multiple muscle-damaging factors during ICU admission, including hyperglycemia, immobility, mechanical ventilation, administration of muscle relaxants, and administration of steroidal anti-inflammatory drugs, may compound the hyper cytokine, hyper nitric oxide, and hyper oxidative conditions, leading to the development of ICU-AW. However, the pathogenesis of ICU-AW remains unclear, and the pathophysiology of ICU-AW awaits further elucidation to develop therapeutic strategies. Recent ICU-AW studies have also revealed that skeletal muscle itself is a key organ in the inflammatory response and metabolic abnormalities in sepsis. In this article, we review the pathophysiology of skeletal muscle in sepsis and international trends in the development of therapeutic agents based on our research results.

[Evaluation of Contractile Function Using Human iPS Cell-derived Cardiomyocytes]

Cardiotoxicity induced by anti-cancer drugs is a significant concern for patients undergoing cancer treatment. Some anti-cancer drugs can damage cardiac muscle cells directly or indirectly, potentially leading to severe heart failure. Various risk factors, including the type and dosage of chemotherapy agents as well as patient background, contribute to the development of cardiotoxicity. Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), which enable patient-specific toxicity prediction, hold great promise in this regard. However, the practical implementation of hiPSC-CMs-based prediction of anti-cancer drug-induced cardiotoxicity still faces hurdles. One major challenge involves establishing and optimizing experimental systems for evaluating contractile dysfunction, the ultimate output of heart failure, using hiPSC-CMs. Such efforts are currently underway globally, focusing on tailoring functional evaluation systems to the characteristics of hiPSC-CMs. In this paper, we provide an overview of the contraction mechanisms of cardiac cells and introduce a method of measuring contraction that we have developed, and discuss the current status of contractile function evaluation methods using hiPSC-CMs.

Determination of single-molecule transport activity of OATP2B1 by measuring the number of transporter molecules using electrophysiological approach

Transporter-mediated clearance is determined by two factors, its single-molecule clearance, and expression level. However, no reliable method has been developed to evaluate them separately. This study aimed to develop a reliable method for evaluating the single-molecule activity of membrane transporters, such as organic anion transporting polypeptide (OATP) 2B1. HEK293 cells that co-expressed large conductance calcium-activated potassium (BK) channel and OATP2B1 were established and used for the following experiments. i) BK channel-mediated whole-cell conductance was measured using patch-clamp technique and divided by its unitary conductance to estimate the number of channels on plasma membrane (QI). ii) Using plasma membrane fraction, quantitative targeted absolute proteomics determined the stoichiometric ratio (ρ) of OATP2B1 to BK channel. iii) The uptake of estrone 3-sulfate was evaluated to calculate the Michaelis constant and uptake clearance (CL) per cell. Single-molecule clearance (CLint) was calculated by dividing CL by QI·ρ. QI and ρ values were estimated to be 916 and 2.16, respectively, yielding CLint of 5.23 fL/min/molecule. We successfully developed a novel method to reliably measure the single-molecule activity of a transporter, which could be used to evaluate the influences of factors such as genetic variations and post-translational modifications on the intrinsic activity of transporters.

Effects of medium-chain fatty acids and tributyrin supplementation in milk replacers on growth performance, blood metabolites, and hormone concentrations in Holstein dairy calves

This study aimed to evaluate the effects of triglycerides containing medium-chain fatty acids (MCT) and tributyrin (TB) supplementation in a milk replacer (MR) on growth performance, plasma metabolites, and hormone concentrations in dairy calves. Sixty-three Holstein heifer calves (body weight at 8 d of age, 41.1 ± 2.91 kg; mean ± SD) were randomly assigned to 1 of 4 experimental MR (28% crude protein and 18% fat): (1) containing 3.2% C8:0 and 2.8% C10:0 (in fat basis) without TB supplementation (CONT; n = 15), (2) containing 6.7% C8:0 and 6.4% C10:0 without TB supplementation (MCT; n = 16), (3) containing 3.2% C8:0 and 2.8% C10:0 with 0.6% (dry matter basis) TB supplementation (CONT+TB; n = 16), (4) containing 6.7% C8:0 and 6.4% C10:0 with 0.6% TB supplementation (MCT+TB; n = 16). The MR were offered at 600 g/d (powder basis) from 8 to 14 d, up to 1,300 g/d from 15 to 21 d, 1,400 g/d from 22 to 49 d, down to 700 g/d from 50 to 56 d, 600 g/d from 57 to 63 d, and weaned at 64 d of age. All calves were fed calf starter, chopped hay, and water ad libitum. The data were analyzed using a 2-way ANOVA via the fit model procedure of JMP Pro 16 (SAS Institute Inc.). Medium-chain fatty acid supplementation did not affect the total dry matter intake. However, calves that were fed MCT had greater feed efficiency (gain/feed) before weaning (0.74 ± 0.098 vs. 0.71 ± 0.010 kg/kg) compared with non-MCT calves. The MCT calves also had a lower incidence of diarrhea compared with non-MCT calves during 23 to 49 d of age and the weaning period (50 to 63 d of age; 9.2% vs. 18.5% and 10.5% vs. 17.2%, respectively). Calves fed with TB had a greater total dry matter intake during postweaning (3,465 vs. 3,232 g/d). Calves fed TB also had greater body weight during the weaning (90.7 ± 0.97 vs. 87.9 ± 1.01 kg) and postweaning period (116.5 ± 1.47 vs. 112.1 ± 1.50 kg) compared with that of non-TB calves. The plasma metabolites and hormone concentrations were not affected by MCT or TB. These results suggest that MCT and TB supplementation in the MR may improve the growth performance and gut health of dairy calves.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

C188-9, a specific inhibitor of STAT3 signaling, prevents thermal burn-induced skeletal muscle wasting in mice

Burn injury is the leading cause of death and disability worldwide and places a tremendous economic burden on society. Systemic inflammatory responses induced by thermal burn injury can cause muscle wasting, a severe involuntary loss of skeletal muscle that adversely affects the survival and functional outcomes of these patients. Currently, no pharmacological interventions are available for the treatment of thermal burn-induced skeletal muscle wasting. Elevated levels of inflammatory cytokines, such as interleukin-6 (IL-6), are important hallmarks of severe burn injury. The levels of signal transducer and activator of transcription 3 (STAT3)-a downstream component of IL-6 inflammatory signaling-are elevated with muscle wasting in various pro-catabolic conditions, and STAT3 has been implicated in the regulation of skeletal muscle atrophy. Here, we tested the effects of the STAT3-specific signaling inhibitor C188-9 on thermal burn injury-induced skeletal muscle wasting in vivo and on C2C12 myotube atrophy in vitro after the administration of plasma from burn model mice. In mice, thermal burn injury severity dependently increased IL-6 in the plasma and tibialis anterior muscles and activated the STAT3 (increased ratio of phospho-STAT3/STAT3) and ubiquitin-proteasome proteolytic pathways (increased Atrogin-1/MAFbx and MuRF1). These effects resulted in skeletal muscle atrophy and reduced grip strength. In murine C2C12 myotubes, plasma from burn mice activated the same inflammatory and proteolytic pathways, leading to myotube atrophy. In mice with burn injury, the intraperitoneal injection of C188-9 (50 mg/kg) reduced activation of the STAT3 and ubiquitin-proteasome proteolytic pathways, reversed skeletal muscle atrophy, and increased grip strength. Similarly, pretreatment of murine C2C12 myotubes with C188-9 (10 µM) reduced activation of the same inflammatory and proteolytic pathways, and ameliorated myotube atrophy induced by plasma taken from burn model mice. Collectively, these results indicate that pharmacological inhibition of STAT3 signaling may be a novel therapeutic strategy for thermal burn-induced skeletal muscle wasting.

Intravenous vagal stimulation catheter, JOHAKU, rapidly decreases heart rate and myocardial oxygen consumption without worsening hemodynamics

Background

Rapid reduction of heart rate (HR) is the most evident physiological response of vagal nerve stimulation (VNS). Since HR reduction is the most potent factor to decrease myocardial oxygen consumption rate (MVO2), the appropriate VNS can exert cardio-protective effects. It is also known that VNS reduces inflammation, oxidative stress, and sympathetic overload. In addition, the VNS during ischemia-reperfusion is known to attenuate myocardial damage by studies in various animal species. Despite the presence of preclinical evidence of VNS benefits, the lack of the device has limited the translation of this technology to clinical practice. We have recently developed an intravenous VNS catheter (JOHAKU, Neuroceuticals Inc.) that can stimulate the right vagal nerve via superior vena cava (SVC) (Figure 1) on temporary basis.

Purpose

We aimed to confirm the feasibility of JOHAKU as a device to modulate heart rate and MVO2 rapidly by a canine experiment.

Methods

In eight beagle dogs, JOHAKU was inserted from the right femoral vein and placed at the SVC level. The stimulation intensity was adjusted to 10–20 V (20 Hz). We simultaneously recorded electrocardiogram and intraarterial blood pressure (BP). In three of eight dogs, we measured the left anterior descending coronary artery flow and oxygen saturations of arterial and coronary sinus blood to calculate MVO2. We compared HR, BP, and MVO2 during JOHAKU stimulation to ones at baseline.

Results

As shown in Figure 2, JOHAKU attenuated HR immediately after stimulation. Compared with baseline, JOHAKU significantly reduced HR (baseline: 135±13 vs. 5 min on stimulation: 107±13 bpm, p&lt;0.05), and did not affect mean BP significantly (96.2±22.8 vs. 89.4±26.6 mmHg, P=0.59). HR promptly recovered to baseline level after JOHAKU stopped. JOHAKU also reduced MVO2 (0.57±0.43 vs. 0.48±0.38 ml/min, p&lt;0.05).

Conclusion

JOHAKU rapidly attenuated cardiac metabolism burden via the rapid HR reduction. The controllability of HR by JOHAKU without affecting BP enables us to apply the VNS even for patients with hemodynamic instability, such as heart failure and acute myocardial infarction.

Funding Acknowledgement

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

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&lt;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&lt;0.01). Conversely, LA origin was more prevalently detected in non-paroxysmal AF cases (48%) compared to paroxysmal AF (20%) (p&lt;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.

Pebbles and sand on asteroid (162173) Ryugu: In situ observation and particles returned to Earth

The Hayabusa2 spacecraft investigated the C-type (carbonaceous) asteroid (162173) Ryugu. The mission performed two landing operations to collect samples of surface and subsurface material, the latter exposed by an artificial impact. We present images of the second touchdown site, finding that ejecta from the impact crater was present at the sample location. Surface pebbles at both landing sites show morphological variations ranging from rugged to smooth, similar to Ryugu's boulders, and shapes from quasi-spherical to flattened. The samples were returned to Earth on 6 December 2020. We describe the morphology of >5 grams of returned pebbles and sand. Their diverse color, shape, and structure are consistent with the observed materials of Ryugu; we conclude that they are a representative sample of the asteroid.

A deep learning algorithm to translate and classify cardiac electrophysiology

The development of induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) has been a critical in vitro advance in the study of patient-specific physiology, pathophysiology, and pharmacology. We designed a new deep learning multitask network approach intended to address the low throughput, high variability, and immature phenotype of the iPSC-CM platform. The rationale for combining translation and classification tasks is because the most likely application of the deep learning technology we describe here is to translate iPSC-CMs following application of a perturbation. The deep learning network was trained using simulated action potential (AP) data and applied to classify cells into the drug-free and drugged categories and to predict the impact of electrophysiological perturbation across the continuum of aging from the immature iPSC-CMs to the adult ventricular myocytes. The phase of the AP extremely sensitive to perturbation due to a steep rise of the membrane resistance was found to contain the key information required for successful network multitasking. We also demonstrated successful translation of both experimental and simulated iPSC-CM AP data validating our network by prediction of experimental drug-induced effects on adult cardiomyocyte APs by the latter.

[Analysis of contractile functions of human iPS-derived cardiomyocytes using motion field imaging]

Although the cardiotoxicity of anti-cancer drugs is an important issue, the underlying mechanisms remain unknown. To develop a sensitive assay system for cardiotoxicity, we examined effects of anticancer drugs on contractile functions of human iPS cell-derived cardiomyocytes by using non-invasive motion field imaging analysis with extended drug exposure time. We succeeded in continuously measuring stable contractile function. The continued exposure revealed that the difference in cardiotoxicity between cardiotoxic doxorubicin and less toxic erlotinib was more evident after 8 days of treatment than with 3 days of treatment, suggesting that continued exposure improved the predictive power for cardiotoxicity of anti-cancer drugs.

Opening of Intermediate Conductance Ca2+-Activated K+ Channels in C2C12 Skeletal Muscle Cells Increases the Myotube Diameter via the Akt/Mammalian Target of Rapamycin Pathway

The activation of potassium channels and the ensuing hyperpolarization in skeletal myoblasts are essential for myogenic differentiation. However, the effects of K⁺ channel opening in myoblasts on skeletal muscle mass are unclear. Our previous study revealed that pharmacological activation of intermediate conductance Ca²⁺-activated K⁺ channels (IK_Ca channels) increases myotube formation. In this study, we investigated the effects of 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DCEBIO), a Ca²⁺-activated K⁺ channel opener, on the mass of skeletal muscle. Application of DCEBIO to C2C12 cells during myogenesis increased the diameter of C2C12 myotubes in a concentration-dependent manner. This DCEBIO-induced hypertrophy was abolished by gene silencing of IK_Ca channels. However, it was resistant to 1 µM but sensitive to 10 µM TRAM-34, a specific IK_Ca channel blocker. Furthermore, DCEBIO reduced the mitochondrial membrane potential by opening IK_Ca channels. Therefore, DCEBIO should increase myotube mass by opening of IK_Ca channels distributed in mitochondria. Pharmacological studies revealed that mitochondrial reactive oxygen species (mitoROS), Akt, and mammalian target of rapamycin (mTOR) are involved in DCEBIO-induced myotube hypertrophy. An additional study demonstrated that DCEBIO-induced muscle hypertrophic effects are only observed when applied in the early stage of myogenic differentiation. In an in vitro myotube inflammatory atrophy experiment, DCEBIO attenuated the reduction of myotube diameter induced by endotoxin. Thus, we concluded that DCEBIO increases muscle mass by activating the IK_Ca channel/mitoROS/Akt/mTOR pathway. Our study suggests the potential of DCEBIO in the treatment of muscle wasting diseases. SIGNIFICANCE STATEMENT: Our study shows that 5,6-dichloro-1-ethyl-1,3-dihydro-2H-benzimidazol-2-one (DCEBIO), a small molecule opener of Ca²⁺-activated K⁺ channel, increased muscle diameter via the mitochondrial reactive oxygen species/Akt/mammalian target of rapamycin pathway. And DCEBIO overwhelms C2C12 myotube atrophy induced by endotoxin challenge. Our report should inform novel role of K⁺ channel in muscle development and novel usage of K⁺ channel opener such as for the treatment of muscle wasting diseases.

Presence of low voltage area predicts atrial tachyarrhythmia inducibility with atrial burst pacing after pulmonary vein isolation

Background

Induction of atrial fibrillation (AF)/atrial tachycardia (AT) by atrial burst pacing following ablation procedure may reflect the presence of residual substrates in the atria that maintain AF. However, the relation between the inducibility and left atrial low voltage area (LVA) has not been established.

Methods

Fifty-nine patients (65 years old, 43 males) with persistent AF who underwent pulmonary vein isolation (PVI)-based ablation were studied. All patients underwent left atrial voltage mapping during sinus rhythm and atrial burst pacing after PVI. Atrial burst pacing was performed with 30-beat at an amplitude of 10V from the ostium of the coronary sinus; increasing from 240 to 320 ppm in steps of 20 ppm or failure to 1:1 atrial capture. Inducibility was defined as AF/AT lasting more than 5 minutes following burst pacing. Left atrial LVA and other co-variates were analyzed with regard to burst pacing positivity.

Results

AF/AT was induced by burst pacing in 23 patients (39%). Univariate analysis revealed that past history of stroke, CHADS2 score and presence of left atrial LVA were significantly associated with the inducibility of AF/AT. Multivariate analysis revealed that only the presence of LVA was associated with the inducibility (OR 1.5: per 10% increase; p=0.04). We focused on the relationship between the extent of LVA and burst positivity. AF/AT inducibility increased as low voltage area increased, and it was as high as 72.7% when low voltage area was more than 20% (P&lt;0.05). Interestingly, induced arrhythmia type was AT rather than AF when low voltage area was more than 20%.

Conclusions

Presence of left atrial LVA is an independent predictor of atrial tachyarrhythmia inducibility after PVI in patients with persistent AF. A large amount of low voltage area is related to AT inducibility rather than AF.

Extent of LVA and burst positivity

Funding Acknowledgement

Type of funding source: None

Commissioning of high current H+/D+ ion beams for the prototype accelerator of the International Fusion Materials Irradiation Facility

The Linear IFMIF (International Fusion Materials Irradiation Facility) Prototype Accelerator (LIPAc) is aiming at demonstrating the low energy section of a 40 MeV/125 mA IFMIF deuteron accelerator up to 9 MeV with a full beam current in cw operation. For such a high-power beam, the LIPAc injector is required to produce a 100 keV D⁺ beam with 140 mA and match it for injection into the Radio Frequency Quadrupole (RFQ) accelerator. The injector is designed by CEA-Saclay based on the high intensity light ion source (SILHI). In 2019, the commissioning of the RFQ to demonstrate the D⁺ beam acceleration at a low duty cycle (0.1%) was conducted. A nominal beam current of 125 mA D⁺ beam was accelerated up to 5 MeV through the RFQ successfully. The LIPAc injector fully satisfied the requirements for RFQ beam commissioning at the pulse mode.

TAK-242, a specific inhibitor of Toll-like receptor 4 signalling, prevents endotoxemia-induced skeletal muscle wasting in mice

Circulating lipopolysaccharide (LPS) concentrations are often elevated in patients with sepsis or various endogenous diseases related to bacterial translocation from the gut. Systemic inflammatory responses induced by endotoxemia induce severe involuntary loss of skeletal muscle, termed muscle wasting, which adversely affects the survival and functional outcomes of these patients. Currently, no drugs are available for the treatment of endotoxemia-induced skeletal muscle wasting. Here, we tested the effects of TAK-242, a Toll-like receptor 4 (TLR4)-specific signalling inhibitor, on myotube atrophy in vitro and muscle wasting in vivo induced by endotoxin. LPS treatment of murine C2C12 myotubes induced an inflammatory response (increased nuclear factor-κB activity and interleukin-6 and tumour necrosis factor-α expression) and activated the ubiquitin-proteasome and autophagy proteolytic pathways (increased atrogin-1/MAFbx, MuRF1, and LC-II expression), resulting in myotube atrophy. In mice, LPS injection increased the same inflammatory and proteolytic pathways in skeletal muscle and induced atrophy, resulting in reduced grip strength. Notably, pretreatment of cells or mice with TAK-242 reduced or reversed all the detrimental effects of LPS in vitro and in vivo. Collectively, our results indicate that pharmacological inhibition of TLR4 signalling may be a novel therapeutic intervention for endotoxemia-induced muscle wasting.

P26 Soluble programed cell death ligand-1 is associated with acute coronary syndrome

Background

Immune checkpoint by programmed cell death (PD)-1 and its ligand (PD-L1) play crucial role in T cell tolerance toward vascular wall antigens. PD-L1 is widely expressed on a number of cells including immune cells and vascular endothelium. It was reported that increased expression of PD-L1 in dendritic cells implicates upregulated inflammation in atherosclerotic lesions that is associated with plaque instability. Although plaque rupture in coronary atherosclerosis is an important pathogenesis of acute coronary syndrome (ACS), the association between PD-L1 and ACS is still unknown.

Purpose

We hypothesize that circulating PD-L1 might be associated with ACS, reflecting endothelial damage and coronary plaque rupture. To elucidate this hypothesis, we compared serum levels of soluble PD-L1 (sPD-L1) in stable coronary artery disease (CAD) patients with those in ACS patients.

Methods

Serum levels of sPD-L1 were measured by using commercially available ELISA kit (Human PD-L1/B7-H1 DuoSet, R&D Systems) in consecutive patients with CAD admitted to our University Hospital from February 2016 to March 2017. Patients with any malignant disease or severe inflammatory disease were excluded from this study. Serum levels of sPD-L1 and clinical backgrounds were compared between stable-CAD and ACS patients.

Results

In total, 269 patients with CAD were enrolled (28 cases [10.4 %] with ACS and 241 cases [89.6 %] with stable-CAD). PD-L1 had no correlation to C-reactive protein, cardiac troponin, and classical atherosclerotic risks such as age, body mass index, estimated glomerular filtration rate, low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol, and hemoglobin A1c. Although age, sex, history of smoking, and the prevalences of hypertension, diabetes mellitus and dyslipidemia were comparable between both groups, the level of LDL-C was significantly higher in patients with ACS compared with those with stable-CAD (94.0 [77.0–112.0] mg/dL vs. 78.5 [65.0–97.0] mg/dL, P = 0.008). Also serum level of sPD-L1 was significantly increased in patients with ACS compared with those with stable-CAD (106.1 [60.9–157.7] pg/mL vs. 64.8 [30.9–102.5] pg/mL, P = 0.003). Univariate logistic regression analysis identified that serum levels of both sPD-L1 and LDL-C were independently associated with ACS. Moreover, multivariable logistic regression analysis with factors from univariate analysis identified that serum level of sPD-L1 was significantly and independently associated with ACS (odds ratio: 1.006, 95 % confidence interval: 1.001–1.012, P = 0.03).

Conclusions

This is the first study to elucidate that the increased serum levels of sPD-L1 was associated with ACS. This study suggests that sPD-L1 could be a risk marker and therapeutic target for ACS.

P6513Temporal trends in coronary intervention strategies and the impact on one-year clinical events: data from a Japanese multi-center real-world cohort study

Background

While it is clear that device technology of percutaneous coronary intervention (PCI) has advanced over the course of the last 40 years and the evidence for improvements in the efficacy of PCI is clear, it is less clear whether the prognosis following PCI continues to improve year by year.

Methods

The Kumamoto Intervention Conference Study Real-World Registry is a multi-center registry that enrolls consecutive patients undergoing PCI in 17 centers in Kyushu area, Japan. To elucidate the clinical impact of recent changes in treatment strategies, 8,841 consecutive participants (historical PCI: n=4,038, enrolled between January 2013 and December 2014, and current PCI: n=4,803, between January 2015 and March 2017) with 1-year follow-up data were analysed. Baseline demographic data, cardiovascular risk factors, and the medication being taken at discharge were documented. The primary endpoint was defined as a major adverse cardiac event (MACE), comprising cardiovascular death or non-fatal MI, including stent thrombosis (ST), occurring within 1 year of PCI.

Results

Regarding the relationships between presenting symptoms and PCI status, ACS, STEMI, NSTEMI, and UAP were similarly common, but the proportion of patients with multi-vessel disease was lower and the proportion with type B2/C lesions was higher in the current PCI group (p=0.004 and p<0.001, respectively). The prevalences of left main trunk lesions and Killip classes III or IV were comparable between the groups, but in-stent restenotic lesions were significantly more frequent in the historical PCI group (p<0.001). In addition to the change in the DAPT regimen, more optimal medical therapy was introduced during this time period, including the use of β-blockers, ACE-Is, and statins.

The incidences of MACE were comparable between historical PCI and current PCI (2.2% vs. 2.1%, p=0.693), even though complex lesions were more frequent during the more recent period. During this period, the use of radial approaches, drug eluting stents, and coronary imaging increased, but the use of intra-aortic balloon pumping (IABP) or thromboaspiration decreased. The incidences of major adverse cardiac or cerebrovascular events (MACCE), cardiac death, non-fatal MI, and stent thrombosis were similar between the historical and current periods (Figure). Multivariate analysis for overall patients, after adjustment, showed that multi-vessel disease, type B2/C lesions, ACS, and DES use were significant independent predictors of MACE.

Figure 1. Comparison of Clinical Events

Conclusion

An improvement in the prognosis associated with PCI has not occurred in recent years. However, the lesions being treated are becoming more complex, and the selection of evidence-based approaches, the use of coronary imaging, and the optimal medication treatments may have contributed to comparable outcomes being maintained.

Acknowledgement/Funding

Daiichi Sankyo Co., Ltd. Japan.

3285Impact of intravascular ultrasound-guided percutaneous coronary intervention in patients with diabetes mellitus and chronic kidney disease

Background

Several studies have shown favorable results using IVUS-guided PCI. Nevertheless, patient background in which use of IVUS is effective is not well elucidated. Patients with diabetes mellitus (DM) or chronic kidney disease (CKD) tend to have complex coronary artery lesions. We sought to assess the impact of IVUS guidance on clinical outcomes in these patients.

Methods

Kumamoto Intervention Conference Study is a multicenter registry which has enrolled consecutive patients who underwent PCI in 16 centers in Japan. Between August 2008 and March 2014, 11,195 consecutive patients were enrolled in this registry. To elucidate the efficacy of IVUS usage in DM and CKD patients, 10,822 consecutive subjects with 1-year follow-up data were analyzed. In this patient population, 69.2% (n=7,493) of patients were treated with IVUS-guided PCI. Patients were divided into 4 groups: the No Risk Group, the DM only Group, the CKD only Group, and the DM+CKD Group.

Results

Maximum stent diameter, post dilatation rate, usage of distal protection device, and rotational atherectomy rate were significantly higher in the IVUS-guided PCI patients in all 4 groups. 1-year MACE (cardiovascular death, non-fatal myocardial infarction, and MI with stent thrombosis) was significantly lower in the IVUS-guided PCI patients than angiography-guided PCI patients in each subset, except for the No Risk Group. In contrast to angiography-guided PCI patients, there were no significant differences among the 4 groups as regards 1-year MACE in the IVUS-guided PCI patients except for the DM+CKD Group. In multiple regression analysis, IVUS usage was an independent negative predictor for 1-year MACE in the DM only Group (HR=0.374, 95% CI 0.194–0.719, p=0.003) and in the CKD only Group (HR=0.604, 95% CI 0.379–0.962, p=0.010). When the No Risk Group was used as a reference, the HR has increased according to increased risk factors in the angiography-guided PCI patients, but such tendency was not necessarily observed in the IVUS-guided PCI patients (Table).

Risk Stratification of DM and CKD Variable IVUS-Guided PCI Angiography-Guided PCI HR 95% CI P HR 95% CI P The No Risk Group Reference – – Reference – –   vs. the DM only Group 0.627 0.321–1.227 0.173 2.036 1.090–3.804 0.026   vs. the CKD only Group 1.334 0.795–2.237 0.275 2.730 1.541–4.836 0.001   vs. the DM+CKD Group 2.114 1.287–3.474 0.014 2.225 1.160–4.266 0.016

Conclusion

The efficacy of IVUS usage as regards 1-year MACE was confirmed in DM and CKD patients, but not observed in patients without them or in the combination of DM and CKD patients.

Acknowledgement/Funding

None

P2613Clinical significance of brachial-ankle pulse wave velocity in patients with heart failure with reduced left ventricular ejection fraction

Background

Heart failure (HF) is characterized as a complex syndrome of structural and functional cardiac disorder that impair ventricular filling and/or blood ejection. Peripheral arterial disease (PAD) is accompanied by systemic inflammation and is frequently associated with other cardiovascular diseases. Although PAD and HF share cardiovascular risk and pathophysiological features, and each has been associated with increased morbidity and mortality. Pulse wave velocity (PWV) is known to be an indicator of arterial stiffness. We previously reported the prognostic significance of brachial–ankle PWV (baPWV) in patients with HF with preserved left ventricular ejection fraction. However, its association with cardiovascular outcomes in HF with reduced EF (HFrEF) and HF with mid-range EF (HFmrEF) patients remains uncertain.

Purpose

The first aim of this study was to investigate the impact of PAD on prognosis in HFrEF and HFmrEF. The second aim was to investigate the relationship between baPWV and the occurrence of cardiovascular events in patients with HFrEF and HFmrEF.

Methods

We measured ankle-brachial pressure index (ABI) and baPWV values at stable condition after optimal therapy for HF in 201 consecutive HFrEF and HFmrEF patients admitted to Kumamoto University Hospital from 2007 to 2015 who were enrolled and followed until the occurrence of cardiovascular events.

Results

The mean age of the two groups of patients was 67.5±11.8 years. The prevalence of PAD, defined as an ABI 0.9 or less, was 14% in patients. Kaplan–Meier analysis revealed that HFrEF and HFmrEF patients with PAD had a significant higher risk of total cardiovascular and HF-related events than those without PAD (P=0.03 and P=0.01, respectively). The hazard ratio (HR) between HFrEF and HFmrEF patients without PAD and those with PAD was compared after adjustment for other confounders. The probabilities of total cardiovascular and HF-related events in HFrEF and HFmrEF patients with PAD were significantly higher than those in HFrEF and HFmrEF patients without PAD (HR: 2.19; 95% CI: 1.02–4.73; P=0.04, and HR: 3.5; 95% CI: 1.27–9.66; P=0.01, respectively). Next, we divided HFrEF and HFmrEF patients without PAD into three groups according to baPWV values. In the Kaplan–Meier analysis, total cardiovascular and HF-related events in the highest baPWV group (1800 cm/s ≤ baPWV) had a significantly higher frequency than those in the mid-level baPWV group (1400 cm/s ≤ baPWV < 1800 cm/s) (P=0.007 and P=0.004, respectively) (Figure A, B). The hazard ratio (HR) between HFrEF and HFmrEF patients in the mid-level baPWV group and those with other baPWV groups was compared after adjustment for other cofounders. The probabilities of total cardiovascular and HF-related events were significantly higher in the highest baPWV group.

Conclusion

Identifying complications of PAD and measuring baPWV values in HFrEF and HFmrEF patients were useful for predicting their prognosis.

P1647Prognostic significance of circulating leukocyte subtype counts in patients with chronic heart failure

Background

Inflammation, characterized by early leukocyte recruitment, is known to be associated with vascular endothelial dysfunction and atherosclerosis. Previous studies have reported that an increased leukocyte count is a risk factor for the progression of atherosclerosis in cardiovascular diseases, and we previously reported that a high monocyte count was an independent and incremental of cardiovascular events in patients with coronary artery disease. Furthermore, previous study also reported that inflammation play a role in the pathophysiology of heart failure (HF), but few studies have evaluated the prognostic role of monocyte in patients with HF.

Purpose

To elucidate the prognostic value of monocyte in HF, we investigated the association of monocyte counts in patients with HF with their future cardiovascular events, and compared them among new categories of HF in this study.

Methods

Consecutive HF patients referred for hospitalization at Kumamoto University Hospital between 2006 and 2015 were registered. Finally, a total of 678 HF patients were enrolled in the study, and were followed prospectively until 2016 or until the occurrence of cardiovascular events. We defined high monocyte group as monocyte counts ≥360/mm3 according to previous clinical reports. We further divided HF patients into three types according to left ventricular ejection fraction (LVEF) (HF with reduced LVEF (HFrEF), HF with mid-range LVEF (HFmrEF), and HF with preserved LVEF (HFpEF)).

Results

In this study, HFrEF was 82 patients, HFmrEF was 118 patients and HFpEF was 478 patients, respectively. The average of total monocyte counts were 397±136 in HFrEF and 375±172 in HFmrEF, and 341±138 in HFpEF patients. Kaplan-Meier analysis revealed that both HFrEF and HFmrEF patients with high monocyte group (≥360 /mm3) had a significant higher risk of HF-related events (P=0.03 and P=0.02, respectively) but not of total cardiovascular events compared with those with low monocyte groups (<360/mm3) (P=0.001). By contrast, high and low monocyte groups in HFpEF patients had no significant difference in both total cardiovascular and HF-related events. Multivariate Cox hazard analysis identified a high monocyte count as an independent and significant predictor of future HF-related events in HFrEF and HFmrEF patients (hazard ratio: 3.02, 95% confidence interval: 1.20–7.59, p=0.018).

Next, by whether they had ischemic heart disease (IHD), we divided HFrEF and HFmrEF patients into two groups. Non-ischemic HF group with high monocyte counts had a significant higher risk of HF-related events compared to those with low monocyte counts (P=0.014). By contrast, there was no statistically significant difference of the occurrences of future HF-related events between in ischemic HF group with high and low monocyte counts.

Conclusion

A high monocyte count was an independent and incremental predictor of HF-related events in HFrEF and HFmrEF especially with IHD, but not in HFpEF patients.

P5480Impact of Silent Myocardial Ischemia on One Year Mortality after Successful Coronary Intervention: Data from Japanese Multicenter (KICS) Registry

Introduction

Under the awareness of appropriate use criteria, the significance of PCI for the patients with silent myocardial ischemia (SMI) decreases. On the other hand, the prognoses of SMI patients have been reported to be equivalent to those of symptomatic effort angina pectoris (EAP) patients. We aimed to clarify the prognosis of SMI after PCI and elucidate the factors influencing the mortality.

Methods

The Kumamoto Intervention Conference Study is multicenter registry enrolling consecutive patients undergoing PCI in 16 centers in Japan. Overall, 17,688 consecutive patients were enrolled during April 2008 to March 2017. To compare the clinical events between SMI and EAP, 8,278 subjects, excluding acute coronary syndrome, post successful PCI were enrolled with 1-year follow-up data.

Results

In this study, 2,071 patients were classified as SMI and 6,207 patients were EAP. Male, lower body mass index (BMI), diabetes, chronic kidney disease (CKD), smoking habits, prior myocardial infarction (MI), composite of cerebrovascular disease and composite of peripheral arterial disease were all significantly higher in the SMI group. Although nonfatal MI and stent thrombosisduring 12-monthswere comparable between the 2 groups, all-cause mortality and cardiac death during 12-months were significantly higher in the SMI group than in the EAP group (3.9% vs 1.8%, p<0.001, 1.4% vs 0.5%, p<0.001, respectively). On the other hand, Repeat Revascularization rate during 12-months was significantly lower in the SMI group than in the EAP group (15.7% vs 19.5%, p<0.001).Kaplan-Meier analysis for cardiac death showed a significant difference between the 2 groups (Figure). In a multiple logistic regression analysis, in addition to lower BMI and CKD, SMI was an independent predictor for cardiac death. Even after adjustment by propensity-score matching with predictive factors for cardiac event, SMI showed a higher cardiac death rate compared with EAP (1.4% vs 0.5%, p=0.004), and it remained as a significant predictor.

Conclusion

In this study, SMI itself was associated with higher mortality after PCI. Strict follow-up and assessment of residual ischemia should be necessary for SMI patients.

P2611The prognostic value of serum magnesium levels in patients with heart failure with preserved left ventricular ejection fraction

Background

In heart failure (HF) patients, various factors, such as hyperactivity of the renin-angiotensin system, influence of drug therapy such as loop and thiazide diuretics, undernutrition and others, can causes hypokalemia and hypomagnesemia. Although serum magnesium (Mg) levels are closely associated with the prognosis of HF patients, the clinical significance of serum Mg levels in cardiovascular outcomes of HF with preserved ejection fraction (HFpEF) patients is not fully understood.

Purpose

We examined the relationship between serum Mg and future HF-related events in patients with HFpEF.

Methods

This study was a retrospective, single-center, observational study. We enrolled 452 consecutive HFpEF patients admitted to our university hospital between January 2007 and September 2013 and followed them for 4 years or until occurrence of HF-related events. We defined lower serum Mg as <2.0 mg/dL (=0.8 mmol/L) and higher serum Mg as ≥2.0 mg/dL based on recent clinical evidences and compared their clinical characteristics and prognosis.

Results

The mean serum Mg level was 2.12 mg/dL (median, 2.1 mg/dL; interquartile range, 2.0–2.28 mg/dL). The follow-up period was 0–50 months (median, 47.3 months) and 48 HF-related events (10.6%) were recorded. The frequency of HF-related events was significantly higher in the lower serum Mg group compared with the higher serum Mg group (n=16, 17.4% vs. n=32, 8.9%; P=0.018). There were no significant differences between groups in the use of all drugs (loop diuretics, mineralcorticoid receptor antagonists, renin-angiotensin-aldosterone system inhibitors, calcium channel blockers, β-blockers, statins and Mg preparations). The lower serum Mg group (n=92) showed significantly higher prevalence of diabetes mellitus (DM), uric acid levels and B-type natriuretic peptide (BNP)levels compared with the higher serum Mg group (n=360). Kaplan-Meier curve revealed a significantly higher probability of HF-related events in the lower serum Mg group compared with the higher serum Mg group (log-rank test, P=0.012, Figure). Multivariate Cox proportional hazard analysis revealed that the lower serum Mg group had significantly and independently higher probabilities of HF-related events compared with those in the higher serum Mg group (hazard ratio: 2.37, 95% confidence intervals: 1.27–4.41, P=0.007). We reclassified the risk of a HF-related events after adding the lower serum Mg to the prognostic factors (age, previous hospitalization for HF, DM, ln-BNP); the continuous net reclassification improvement was 29.0% (p=0.041).

Conclusion

We first demonstrated that serum Mg was significantly correlated with the occurrence of future HF-related events in HFpEF patients. Lower serum Mg is able to successfully predict future HF-related events, and management of serum Mg in HFpEF patients is thus important.

Acknowledgement/Funding

None

P3392Potential of imaging-guided PCI for event suppression in Japanese acute myocardial infarction patients: J-MINUET substudy

Background

Intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) has been widely used in clinical settings. Although favorable results of imaging-guided percutaneous coronary intervention (PCI) compared with angio-guided PCI were observed in several studies, impacts of institutional-based usage frequency, about imaging-guided PCI, have not been well elucidated.

Methods

To elucidate the impact of imaging-guided PCI and the effects of frequency of its usage, we analyzed data of the Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET). This was a prospective and multicenter registry consisting of 3,283 AMI patients, who were hospitalized within 48 hours of onset from July 2012 to March 2014. Clinical follow-up data was obtained for 3 years. In this sub-study, a total of 2,788 patients who underwent urgent PCI having detailed procedural information were enrolled. We analyzed the differences of utilization rates of imaging-guided PCI among the participating institutions and the impacts for the clinical events. The participating institutions were divided into 3 groups by the frequency of IVUS usage: low frequency institutions: under 50%; moderate frequency institutions: 50% to 90%; and, high frequency institutions: over 90%.

Results

In this cohort registry, patients were enrolled from 28 institutions. The utilization rate of coronary imaging varied widely depending on each institution from 15.4% to 100% (mean 85.7%±24.3, median 97.4%). When the institutions were divided into 3 groups by the frequency of intravascular imaging usage, four low frequency institutions enrolled 295 patients, five moderate frequency institutions enrolled 624 patients, and 19 high frequency institutions enrolled 1,491 patients. Although the incidence of MACE (death, MI, stroke, cardiac failure, or revascularization for unstable angina) decreased stepwise (33.2%, 23.7%, and 19.7%) (gray bar in the Figure), the event rates of the imaging-guided PCI cases among the 3 groups were comparable (21.6%, 21.9%, and 19.6%) (white bar in the Figure). On the other hand, a gradual event reduction between the 3 groups was observed in the angio-guided PCI cases (black bar in the Figure). In comparison of MACE rate between imaging-guided and angio-guided PCI, there were statistically significant differences in the low frequency and moderate frequency institutions (p=0.001 and p=0.012, respectively). In contrast, comparable event rates were observed in the high frequency institutions (p=0.441).

MACE rate by imaging usage frequency

Conclusions

In Japanese ACS patients treated with imaging-guided PCI, better suppression of clinical events during 3-year was found in the institutions with the more frequent use of intravascular imaging, mainly due to stepwise event suppression in the cases of angio-guided PCI. On the other hand, the clinical benefit of coronary imaging was obtained independently of the frequency of use and its experience.

P3764Morphological mechanisms of atrial functional mitral regurgitation in patients with atrial fibrillation

Background

Atrial functional mitral regurgitation (AFMR) occurs in patients with atrial fibrillation. However, morphological mechanisms of AFMR are poorly understood.

Purpose

The purpose of this study was to examine the morphological characteristics in patients with AFMR.

Methods

Among consecutive 795 patients undergoing initial radiofrequency catheter ablation (RFCA) at our hospital, twenty-five patients with persistent AF accompanied by AFMR (≥ moderate) before RFCA (AFMR group) were studied. Age-matched 25 patients with persistent AF without MR were defined as a control group.

Results

Left ventricular ejection fraction (LVEF) was lower and left atrium volume index was larger in the AFMR group (Table). Mitral valve annulus diameter and length of anterior mitral leaflet (AML) were similar between groups, whereas length of posterior mitral leaflet (PML) was significantly shorter in the AFMR group. Smaller tethering angle of AML (γ in the figure) and shorter tethering height were significantly associated with the occurrence of AFMR, which were different from morphology of functional mitral regurgitation in patients with dilated LV. Multiple regression analysis revealed that less tenting height (p<0.05) and LA dilatation toward the posterior (p<0.01) were significantly related to AFMR.

Echocardiographic parameters AFMR (n=25) Control (n=25) P value Age, y 69±8 66±10 NS Male, n (%) 9 (36) 20 (80) P=0.001 LVEF,% 60±9 67±6 P=0.004 LAD, mm 44±5 41±7 NS LAVI, ml/m2 56±17 41±13 P<0.001 MV diameter, mm 3.9±0.4 3.8±0.5 NS α angle, ° 34±9 35±7 NS β angle, ° 48±9 50±8 NS γ angle, ° 32±5 37±5 P=0.0005 AML length, mm 3.0±0.5 3.0±0.5 NS PML length, mm 2.1±0.1 2.4±0.1 P=0.03 Tenting height, mm 1.5±0.1 1.8±0.1 P=0.02 D, mm 0.8±0.3 0.5±0.3 P=0.001 LVEF: left ventricular ejection fraction; LAD: left atrial diameter; LAVI: left atrial volume index; AML: anterior mitral leaflet; PML: posterior mitral leaftlet.

Conclusions

AFMR occurs in patients with unique morphological features, such as less tethering height and LA dilatation toward the posterior.

P1025Clinical predictors for the improvement of left ventricular ejection fraction and prognosis after catheter ablation of atrial fibrillation in patients with systolic dysfunction

Background

Catheter ablation (CA) of atrial fibrillation (AF) improves left ventricular ejection fraction (LVEF) and clinical outcomes in patients with left ventricular systolic dysfunction (LVSD). However, predictors of the improvement of LV function and clinical outcomes by CA were poorly understood.

Purpose

We examined the efficacy of CA in AF patients with LVSD and predictive factors associated with clinical outcomes.

Method

Among consecutive 795 patients undergone initial RFCA at our hospital, we studied 51 patients with LVSD (LVEF ≤50%). Improved LVEF more then 5% at 1-year after CA was classified as “responder” to CA. We analyzed clinical variables and echocardiographic parameters before and after the CAs.

Results

In the responder group, LVEF was significantly improved 1-year after catheter ablation compared with the non-responder group. (ΔLVEF 22±12% vs. −1±4%, p<0.001). The responder group was significantly younger, had more non-paroxysmal AF, smaller LV systolic diameter and lower plasma BNP level before CA (Table). Late gadolinium enhancement (LGE)-positive rate in cardiovascular magnetic resonance imaging (CMR) before CA was higher in the non-responder group than in the responder group (100% [6/6] vs. 38% [5/13], p<0.005). After CAs of AF, event-free survival from hospitalization for heart failure was significantly higher in the responder group (Figure) with less AF recurrence (27% vs. 47%, p=0.04) than in the non-responder group.

Baseline characteristics Responder (N=35) Non-Responder (N=16) P value Age, y 62±11 69±8 p<0.01 Male, n (%) 26 (74) 13 (76) NS Non-pAF 26 (74) 4 (24) p<0.01 LAD, mm 48±7 48±8 NS LAVI, ml/m2 54±17 58±20 NS LVDd, mm 54±7 58±10 NS LVDs, mm 43±7 48±10 p=0.05 EF, % 37±8 38±8 NS BNP (pg/ml) 278±225 684±848 p<0.05

Conclusion

Younger age, absence of LV dilatation, lower plasma BNP, or absence of LGE may well predict favorable clinical outcomes after CA in patients with LVSD.

P4334Effects of Asian dust on blood pressure and blood cell counts: a cross-sectional study of health check-up data

Introduction

Asian dust (AD) is one of the health care problems because AD increases risk for mortality, respiratory, and cardiovascular disease. Previous animal studies showed that particulate matter from AD induced oxidative stress and systemic inflammation, increased blood pressure and heart rate, and decreased cardiac contraction. However, few reports show association of AD with increased blood pressure in human healthy subjects.

Purpose

The aim of this study was to investigate effects of AD on blood pressure and blood cell counts in human.

Methods

Using generalized linear models, we estimated the association between short-term exposure to AD and systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and white blood cell (WBC) count in 296,168 participants aged 20 and older (men n=168,579, 56.9%) who underwent medical check-ups and had no anti-hypertensive agents between April 2005 and March 2015 in a health check-up center in Japan. AD days were the days on which AD events occurred, which were defined as decreased visibility (<10km) due to AD monitored by local meteorological observatory. Propensity score matching analysis was performed to reduce the effects of possible confounders such as age, sex, mean temperature, humidity. In multivariable generalized linear models, data of other air pollutant such as SO2, NO2, Ox or suspended particulate matter was used as covariate.

Results

During study period, 61 AD days were observed, and there were 4,670 participants undergoing medical check-ups on AD days. In the propensity score matched population (n=4,670, each), short-term exposure to AD was significantly associated with an increased risk of higher SBP, DBP, HR, or WBC count [β=1.303, 95% confidence interval (CI) 0.577 to 2.029 for SBP, β=0.630, 95% CI 0.122 to 1.138 for DBP, β=0.987, 95% CI 0.410 to 1.563 for HR, β=150.0, 95% CI 64.9 to 235.1 for WBC]. These significant associations were also observed in two-pollutant models. In subgroup analysis according to age, AD exposure had greater impact on SBP, DBP, and HR in younger people (20 to 40 years old), but WBC count in middle-high age (51 years and older).

GLM analysis according to age category

Conclusions

The present study showed that short-term exposure to AD was associated with higher SBP, DBP, HR and WBC count. Short-term exposure to AD may exacerbate sympathetic nervous system for the young and immune system for the elderly.

P1954Prognostic value of the CHADS2 score for adverse cardiovascular events in acute myocardial infarction patients without atrial fibrillation: J-MINUET Substudy

Background

The CHADS2score has mainly been used to predict the likelihood of cerebrovascular accidents in patients with atrial fibrillation. However, increasing attention is being paid to this scoring system for risk stratification of patients with coronary artery disease. We investigated the value of the CHADS2 score in predicting cardiovascular events in Japanese acute myocardial infarction (AMI) patients without atrial fibrillation.

Methods

To elucidate the prognostic value of CHADS2score in AMI patients, we analysed data of the Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET). This was a prospective and multicenter registry consisting of 3,283 AMI patients, who were hospitalized within 48-hours of onset from July 2012 to March 2014. We calculated the CHADS2 scores for 3,044 patients without clinical evidence of atrial fibrillation. The presence of heart failure was substituted by Killip classification>2 on admission. Clinical follow-up data was obtained for 3 years. In addition to the in-hospital mortality,we evaluated cardiovascular events, defined as all cause deathor non-fatal MI during 3-year follow up periods.

Results

In this study, enrolled patients were classified into low- (point 0–1), intermediate- (point 2–3), and high-score (point 4–6) groups by calculating CHADS2 score. Overall patients with low, intermediate and high score were divided into 1,395, 1,393 and 256 patients, respectively. In-hospital mortality among low, intermediate, and high score groups were 2.8%, 7.4% and 14.8%, respectively (P<0.001). The incidence of cardiovascular eventsamong low, intermediate, and high score groups were 7.8%, 16.3%, 29.3%, respectively (P<0.001). Kaplan-Meier analysis showed a significant difference between the groups (Figure). The event rates were significantly higher in both high score and intermediate score group than in low score group (P<0.001). Multivariate Cox hazard analysis identified CHADS2 score (per 1 point) as an independent predictor of cardiovascular events in addition to chronic kidney disease and lower body mass index. (hazard ratio, 1.344; 95% CI, 1.239–1.459; P<0.001). Among the factors constituting CHADS2 score, heart failure and age were identified as independent predictors for in-hospital mortality. With respect to the cardiovascular event during 3 years, heart failure, age, and previous stroke were revealed as significant independent predictors.

Conclusion

This large cohort study indicated that the CHADS2 score is useful for the prediction of in-hospital mortality and the cardiovascular events during 3-year follow up in Japanese AMI patients without atrial fibrillation.

Continued exposure of anti-cancer drugs to human iPS cell-derived cardiomyocytes can unmask their cardiotoxic effects

Although the cardiotoxicity of anti-cancer drugs is an important issue, the underlying mechanisms remain unknown. To develop a sensitive assay system for cardiotoxicity, we examined effects of anti-cancer drugs on contractile functions of human iPS cell-derived cardiomyocytes by using non-invasive motion field imaging analysis with extended drug exposure time. We succeeded in continuously measuring stable contractile function. The continued exposure revealed that the difference in cardiotoxicity between cardiotoxic doxorubicin and less toxic erlotinib was more evident after 8 days of treatment than with 3 days of treatment, suggesting that continued exposure improved the predictive power for cardiotoxicity of anti-cancer drugs.

Scoring System to Predict pt2 in Gallbladder Cancer Based on Carcinoembryonic Antigen and Tumor Diameter

BACKGROUND AND AIMS

T2 gallbladder cancer requires lymph node dissection for curative resection, whereas simple cholecystectomy is adequate to treat T1 gallbladder cancer. Hence, this study aimed to develop an accurate scoring system to preoperatively predict pT2 in gallbladder cancer.

MATERIAL AND METHODS

We retrospectively assessed data from 57 patients with suspected gallbladder cancer who underwent curative resection between September 2003 and May 2017. Six with apparent invasion of adjacent organs on preoperative images were excluded. We evaluated preoperative computed tomography, magnetic resonance and endoscopic ultrasonographic images, blood biochemistry, and the maximum standard uptake value in fluorodeoxyglucose-positron emission tomography images. We analyzed whether correlations between preoperative findings and the depth of tumor invasion could predict pT2.

RESULTS

The pathological diagnosis was gallbladder cancer in 30 (58.8%) patients, of whom 21 (69.9%) had pT2 or worse. Multivariate analyses selected carcinoembryonic antigen and tumor diameter as independent predictors of pT2 or worse (odds ratios = 1.741 and 1.098, respectively; 95% confidence intervals = 1.004-3.020 and 1.008-1.197, respectively). A regression formula was created using carcinoembryonic antigen and tumor diameter to calculate pT2 predictive scores. The area under the receiver operating characteristics curve of the pT2 predictive score was 0.873.

CONCLUSION

We created a scoring system to predict pT2 in gallbladder cancer using carcinoembryonic antigen and tumor diameter. The present findings suggested that carcinoembryonic antigen is important for the preoperative evaluation of gallbladder cancer.

Involvement of sex hormonal regulation of K+ channels in electrophysiological and contractile functions of muscle tissues

Sex hormones, such as testosterone, progesterone, and 17β-estradiol, control various physiological functions. This review focuses on the sex hormonal regulation of K⁺ channels and the effects of such regulation on electrophysiological and contractile functions of muscles. In the cardiac tissue, testosterone and progesterone shorten action potential, and estrogen lengthens QT interval, a marker of increased risk of ventricular tachyarrhythmias. We have shown that testosterone and progesterone in physiological concentration activate KCNQ1 channels via membrane-delimited sex hormone receptor/eNOS pathways to shorten the action potential duration. Mitochondrial K⁺ channels are also involved in the protection of cardiac muscle. Testosterone and 17β-estradiol directly activate mitochondrial inner membrane K⁺ channels (Ca²⁺ activated K⁺ channel (K_Ca channel) and ATP-sensitive K⁺ channel (K_ATP channel)) that are involved in ischemic preconditioning and cardiac protection. During pregnancy, uterine blood flow increases to support fetal growth and development. It has been reported that 17β-estradiol directly activates large-conductance Ca²⁺-activated K⁺ channel (BK_Ca channel) attenuating arterial contraction. Furthermore, 17β-estradiol increases expression of BK_Ca channel β1 subunit which enhances BK_Ca channel activity by DNA demethylation. These findings are useful for understanding the mechanisms of sex or generation-dependent differences in the physiological and pathological functions of muscles, and the mechanisms of drug actions.

Effective multiple sideband generation using an electro-optic modulator for a multiple isotope magneto-optical trap

Herein, we report an effective method for the generation of radio-frequency (RF) sidebands in an electro-optic modulator for the simultaneous magneto-optical trapping of two isotopes. This is achieved by switching the RF signals alternately, which suppresses the generation of unwanted frequency signals and improves the laser power per sideband. The generated sidebands are successfully applied to a dual-rubidium-isotope magneto-optical trap (MOT), which results in an increased number of trapped atoms. This simple, flexible, and robust technique can be implemented in experiments that require a large number of atoms in multiple-isotope MOTs and for various applications.