Differential Prognostic Impact of Risk-Prediction Models for Heart Failure in Acute Myocardial Infarction: The Original and Revised Heart Failure Time-Points

Background: We previously developed a risk-scoring system for heart failure (HF) in patients with acute myocardial infarction (MI), namely "HF time-points (HFTPs)". In the original HFTPs, the presence of HF on admission, during hospitalization, and at short-term follow-up was individually scored. This study examined whether the revised HFTPs, with additional scoring of previous HF, provide better predictivity. Methods: This multicenter registry included a total of 1331 patients with acute MI undergoing percutaneous coronary intervention. HF was evaluated at four time-points before and after acute MI onset: (1) a history of HF; (2) elevated natriuretic peptide levels on admission; (3) in-hospital HF events; and (4) elevated natriuretic peptide levels at a median of 31 days after the onset. When HF was present at each time-point, one point was assigned to a risk scoring system, namely the original and revised HFTPs, ranging from 0 to 3 and from 0 to 4. The primary endpoint was a composite of cardiovascular death and HF rehospitalization after discharge. Results: Of the 1331 patients, 65 (4.9%) had the primary outcome events during a median follow-up period of 507 (interquartile range, 335-1106) days. The increase in both original and revised HFTPs was associated with an increased risk of the primary outcomes in a stepwise fashion with similar diagnostic ability. Conclusions: The original and revised HFTPs were both predictive of long-term HF-related outcomes in patients with acute MI undergoing percutaneous coronary intervention. Yet, the original HFTPs may be sufficient to estimate HF risks after MI.

Prognostic Impact of Previous Atherosclerotic Cardiovascular Disease on Short- and Long-Term Outcomes in Acute Myocardial Infarction

Patients with previous atherosclerotic cardiovascular disease (ASCVD) are typically managed by secondary prevention modalities; however, they may experience recurrent events. In acute myocardial infarction (MI), the prognostic effect of preexisting ASCVD on the short- and long-term outcomes remains uncertain. This retrospective, multicenter registry included 2,475 patients with acute MI who underwent percutaneous coronary intervention. Previous ASCVD was defined as a history of ischemic events in the coronary, cerebral, and peripheral arterial territories. Patients were divided into 2 groups according to preexisting ASCVD. The primary end point was major adverse cardiovascular events (MACEs), defined as a composite of cardiovascular death, recurrent MI, and ischemic stroke during hospitalization and after discharge. The bleeding outcomes were also evaluated. Of the 2,475 patients, 475 (19.2%) had previous ASCVD. Patients with previous ASCVD were older and likely to have more co-morbidities than those without ASCVD. During hospitalization, the MACE rates were higher in the ASCVD group than in the non-ASCVD group (16.4% vs 9.6%, p <0.001). Similarly, during a median follow-up of 542 days after discharge, patients with previous ASCVD had an increased risk of MACEs than those without ASCVD (13.4% vs 5.6%, p <0.001). The multivariable analyses identified previous ASCVD as a factor that was significantly associated with MACEs after discharge. Major bleeding events occurred more frequently in the ASCVD group than in the non-ASCVD group. In conclusion, preexisting ASCVD was often observed in patients with acute MI and was particularly associated with long-term ischemic outcomes after discharge; thus, further clinical investigations are needed in this vulnerable patient subset.

Risk factors for surgical site infection following orthopaedic surgery for fracture by trauma: a nested case-control study

BACKGROUND

Surgical site infection (SSI) is associated with higher medical expenses and lower patient quality of life.

AIM

To identify specific modifiable risk factors for SSI after orthopaedic surgery for fractures caused by trauma.

METHODS

This nested case-control study used a nationwide trauma registry, the Japan Trauma Data Bank (JTDB) database. Patient data from 280 hospitals between January 2004 and May 2019 were retrieved from the JTDB. Patients with SSI and identified patients without SSI as control subjects were included, using propensity score matching adjusted for unmodifiable factors. Risk factors associated with SSI after orthopaedic trauma surgery were assessed using multi-level mixed-effects logistic regression models.

FINDINGS

In total, 15,910 patients were included in the analysis. Of these patients, 377 (2.4%) had SSI. After propensity score matching, 258 patients with SSI and 2580 matched patients without SSI were selected. In the multi-level mixed-effects logistic regression analysis, blood transfusion within 24 h (odds ratio (OR): 1.51; 95% confidence interval (CI): 1.06-2.13) was a significant risk factor for SSI following orthopaedic fracture surgery. The OR (95% CI) values for external fixation, transcatheter arterial embolization, and tourniquet for SSI following orthopaedic fracture surgery were 1.40 (0.96-2.03), 1.66 (0.81-3.38), and 2.99 (0.60-14.87), respectively.

CONCLUSION

These findings highlight the necessity of exercising caution when implementing blood transfusion within 24 h as a risk factor associated with SSI following orthopaedic trauma surgery.

The Combinations of the Patterns of Non-adherence to Anti-platelet Regimen in Stented Patients (PARIS) and Coronary Revascularization Demonstrating Outcome Study in Kyoto (CREDO-Kyoto) Thrombotic and Bleeding Risk Scores on Clinical Outcomes in Patients with Acute Myocardial Infarction

Objective The Patterns of Non-adherence to Anti-platelet Regimen in Stented Patients (PARIS) and Coronary Revascularization Demonstrating Outcome Study in Kyoto (CREDO-Kyoto) thrombotic and bleeding risk scores were established to predict ischemic and bleeding events in patients undergoing percutaneous coronary intervention (PCI). However, whether or not the combination of these risk scores is predictive of clinical outcomes is unclear. Methods This bicenter registry included a total of 1,098 patients with acute myocardial infarction (MI) undergoing primary PCI. Patients were divided into three groups according to the PARIS and CREDO-Kyoto thrombotic and bleeding risk scores. The study endpoints included the rates of both ischemic (cardiovascular death, recurrent MI, and ischemic stroke) and major bleeding (Bleeding Academic Research Consortium type 3 or 5) events at two years. Results Two years after primary PCI, ischemic and major bleeding events occurred in 17.3% and 10.2% of patients, respectively. The higher-risk categories of PARIS and CREDO-Kyoto scores were associated with increased risks of ischemic and bleeding events. The rates of ischemic and major bleeding events progressively increased with the increase in risk categories in the two risk scoring systems. In the receiver operating characteristic curve analysis, the addition of CREDO-Kyoto thrombotic and bleeding risk scores to PARIS scores significantly improved diagnostic ability in predicting ischemic (area under the curve: 0.59 vs. 0.63, p=0.01) and bleeding (area under the curve: 0.65 vs. 0.68, p=0.01) events. Conclusion The combinations of the PARIS and CREDO-Kyoto risk scores might be useful for evaluating ischemic and bleeding risks in patients with acute MI undergoing primary PCI.

Innervation of the coronary arteries and its role in controlling microvascular resistance

The coronary circulation plays a crucial role in balancing myocardial perfusion and oxygen demand to prevent myocardial ischemia. Extravascular compressive forces, coronary perfusion pressure, and microvascular resistance are involved to regulate coronary blood flow throughout the cardiac cycle. Autoregulation of the coronary blood flow through dynamic adjustment of microvascular resistance is maintained by complex interactions among mechanical, endothelial, metabolic, neural, and hormonal mechanisms. This review focuses on the neural mechanism. Anatomy and physiology of the coronary arterial innervation have been extensively investigated using animal models. However, findings in the animal heart have limited applicability to the human heart as cardiac innervation is generally highly variable among species. So far, limited data are available on the human coronary artery innervation, rendering multiple questions unresolved. Recently, the clinical entity of ischemia with non-obstructive coronary arteries has been proposed, characterized by microvascular dysfunction involving abnormal vasoconstriction and impaired vasodilation. Thus, measurement of microvascular resistance has become a standard diagnostic for patients without significant stenosis in the epicardial coronary arteries. Neural mechanism is likely to play a pivotal role, supported by the efficacy of cardiac sympathetic denervation to control symptoms in patients with angina. Therefore, understanding the coronary artery innervation and control of microvascular resistance of the human heart is increasingly important for cardiologists for diagnosis and to select appropriate therapeutic options. Advancement in this field can lead to innovations in diagnostic and therapeutic approaches for coronary artery diseases.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Diagnostic ability of Japanese version of high bleeding risk criteria for ischemic outcomes in patients with acute myocardial infarction

The Japanese version of high bleeding risk (J-HBR) criteria was domestically proposed to identify patients at HBR after percutaneous coronary intervention (PCI). The applicability of J-HBR on bleeding events has been validated, while whether J-HBR predicts ischemic events is uncertain. This bi-center registry included 904 patients with acute myocardial infarction (MI) undergoing primary PCI. Patients were stratified by the J-HBR major (1 point) and minor (0.5 point) criteria. Patients with J-HBR ≥ 1 point were diagnosed as having HBR. The primary endpoint was major adverse cardiovascular events (MACE), a composite of cardiovascular death, recurrent MI, and ischemic stroke, after discharge. Of the 904 patients, 451 (49.9%) had the J-HBR. The primary endpoint more frequently occurred in patients with J-HBR than in those without (10.9% vs. 4.9%, p < 0.001) during the median follow-up period of 522 days. Probability of MACE was progressively increased with the increase in the number of J-HBR major and minor criteria, in which severe anemia, severe chronic kidney disease, prior heart failure, peripheral artery disease, and prior ischemic stroke were identified as significant factors associated with MACE. In patients with acute MI undergoing PCI, the J-HBR criteria were predictive for ischemic outcomes after discharge, suggesting that the J-HBR criteria may be useful to identify patients at high bleeding and ischemic risks.

Iodine contrast volume reduction in preoperative transcatheter aortic valve implantation computed tomography: Comparison with 64- and 256-multidetector row computed tomography

INTRODUCTION

This study aimed to compare the vascular enhancement and radiation dose in preoperative transcatheter aortic valve implantation (TAVI) computed tomography (CT) with a reduced contrast medium (CM) using volume scans in 256-multidetector row CT (MDCT) with a standard CM using 64-MDCT.

METHODS

This study included 78 patients with preoperative TAVI CT with either 64- or 256-MDCT. The CM was injected at 1.5 mL/kg in the 64-MDCT group and 1.0 mL/kg in the 256-MDCT group. We compared vascular enhancement of the aortic root and access routes, image quality (IQ) scores, and radiation dose in both groups.

RESULTS

Despite the reduced CM (by 33 %) in the 256-MDCT group, the mean vascular enhancement of the right and left subclavian arteries was significantly higher than that in the 64-MDCT group [284 and 267 Hounsfield units (HU) vs. 376 and 359 HU; p < 0.05]; however, no significant differences in the mean vascular enhancement in the ascending aorta, abdominal aorta at the celiac level, and bilateral common femoral arteries were observed between the two groups (p > 0.05 for all). The median IQ scores at the aortic root were higher in the 256-MDCT group than in the 64-MDCT group (3 vs. 4; p < 0.05), and those at the femoral access routes were comparable (4 vs. 4; p = 0.33). The mean effective dose was significantly reduced by 30 % in the 256-MDCT group (23.6 vs. 16.3 mSv; p < 0.05).

CONCLUSION

In preoperative TAVI CT, volume scans using 256-MDCT provide comparable or better vascular enhancement and IQ with a 30 % reduction in CM and radiation dose than those using 64-MDCT.

IMPLICATIONS FOR PRACTICE

Volume scan using 256-MDCT for preoperative TAVI CT may reduce CM and radiation dose in TAVI patients with renal dysfunction.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Differential Impact of Clinical Factors for Predicting High Platelet Reactivity on Clinical Outcomes in Acute Myocardial Infarction Patients Treated With Clopidogrel and Prasugrel

AIMS

Several scoring systems, including the ABCD-GENE and HHD-GENE scores incorporating clinical and genetic factors, have been developed to identify patients likely to have high platelet reactivity on P2Y12 inhibitors, leading to increased risks of ischemic events. However, genetic testing is not widely available in daily practice. We aimed to evaluate the differential impact of clinical factors in the scores on ischemic outcomes in patients treated with clopidogrel and prasugrel.

METHODS

This bi-center registry included 789 patients with acute myocardial infarction (MI) undergoing percutaneous coronary intervention and treated with either clopidogrel or prasugrel at discharge. The relations of the number of clinical factors included in the ABCD-GENE (age ≥ 75 years, body mass index ＞30 kg/m2, chronic kidney disease, and diabetes) and HHD-GENE (hypertension, hemodialysis, and diabetes) scores to the primary endpoint of major cardiovascular events after discharge, a composite of death, recurrent MI, and ischemic stroke, were evaluated.

RESULTS

The number of clinical factors in the ABCD-GENE score was not predictive of ischemic outcomes after discharge in patients treated with clopidogrel and/or prasugrel, while the increase in the number of clinical factors of the HHD-GENE score was associated with an increased risk of the primary endpoint in a stepwise manner in patients on a P2Y12 inhibitor.

CONCLUSIONS

Clinical factors listed in the HHD-GENE score may help stratify ischemic risks in patients with acute MI treated with clopidogrel and prasugrel, whereas risk stratification without genetic testing in patients treated with clopidogrel may be challenging.

Broadband design of silica-PLC mode-dependent-loss equalizer for 2LP-mode transmission systems

A new configuration of mode-dependent-loss (MDL) equalizer for two linearly-polarized mode transmission systems using the silica planar lightwave circuit platform is proposed. This device acts as an LP01-mode attenuator (precisely, LP01/LP21 mode converter) to adjust the MDL keeping a high transmission of the LP11 modes. Almost all components constructing the device are based on the adiabatic mode conversion, which brings broadband operation. Especially, a newly proposed E12/E22 mode converter plays a key role in broadband MDL equalization. It is numerically revealed that the flattened spectra with designated transmission can be obtained for the wavelength from 1200 nm to 1650 nm.

Antiferromagnetic topological insulator with selectively gapped Dirac cones

Antiferromagnetic (AF) topological materials offer a fertile ground to explore a variety of quantum phenomena such as axion magnetoelectric dynamics and chiral Majorana fermions. To realize such intriguing states, it is essential to establish a direct link between electronic states and topology in the AF phase, whereas this has been challenging because of the lack of a suitable materials platform. Here we report the experimental realization of the AF topological-insulator phase in NdBi. By using micro-focused angle-resolved photoemission spectroscopy, we discovered contrasting surface electronic states for two types of AF domains; the surface having the out-of-plane component in the AF-ordering vector displays Dirac-cone states with a gigantic energy gap, whereas the surface parallel to the AF-ordering vector hosts gapless Dirac states despite the time-reversal-symmetry breaking. The present results establish an essential role of combined symmetry to protect massless Dirac fermions under the presence of AF order and widen opportunities to realize exotic phenomena utilizing AF topological materials.

Effect of admission in the stroke care unit versus intensive care unit on in-hospital mortality in patients with acute ischemic stroke

BACKGROUND/OBJECTIVE

Few reports have directly compared the outcomes of patients with acute ischemic stroke (AIS) who are managed in a stroke care unit (SCU) with those who are managed in an intensive care units (ICU). This large database study in Japan aimed to compare in-hospital mortality between patients with AIS admitted into SCU and those admitted into ICU.

METHODS

Patients with AIS who were admitted between April 1, 2014, and March 31, 2019, were selected from the administrative database and divided into the SCU and ICU groups. We calculated the propensity score to match groups for which the admission unit assignment was independent of confounding factors, including the modified Rankin scale (mRS) score. The primary outcome was in-hospital mortality, and secondary outcomes were the mRS score at discharge, length of stay (LOS), and total hospitalization cost.

RESULTS

Overall, 8,683 patients were included, and 960 pairs were matched. After matching, the in-hospital mortality rates of the SCU and ICU groups were not significantly different (5.9% vs. 7.9%, P = 0.106). LOS was significantly shorter (SCU = 20.9 vs. ICU = 26.2 days, P < 0.001) and expenses were significantly lower in the SCU group than in the ICU group (SCU = 1,686,588 vs. ICU = 1,998,260 yen, P < 0.001). mRS scores (score of 1-3 or 4-6) at discharge were not significantly different after matching. Stratified analysis showed that the in-hospital mortality rate was lower in the ICU group than in the SCU group among patients who underwent thrombectomy.

CONCLUSIONS

In-hospital mortality was not significantly different between the ICU and SCU groups, with significantly lower costs and shorter LOS in the SCU group than in the ICU group.

Characterising the performance of an ultrawide field-of-view 3D atom probe

The CAMECA Invizo 6000 atom probe microscope uses ion optics that differ significantly from the local electrode atom probe (LEAP). It uses dual antiparallel deep ultraviolet lasers, a flat counter electrode, and a series of accelerating and decelerating lenses to increase the field-of-view of the specimen without reducing the mass resolving power. In this work we characterise the performance of the Invizo 6000 using three material case studies: a model Al-Mg-Si alloy, a commercially-available Ni-based superalloy, and a Zr alloy, using a combination of air and vacuum-transfer between instruments. The ion optics of the Invizo 6000 significantly increase the field-of-view compared to the same specimen on a LEAP 4000 X Si. We also observe a significant increase in specimen yield, especially for the Zr alloy. These results combine to make the Invizo 6000 well-suited to research projects requiring large analysis volumes, particularly so for traditionally difficult samples such as oxides.

Understanding Cardiac Anatomy and Imaging to Improve Safety of Procedures: The Right Ventricle

Right ventricular perforation is a catastrophic complication of catheter-based intracardiac interventions. In this context, appreciation of 5 attachments of the right ventricle to the aortoventricular unit is essential to recognize extent of right ventricular free wall. We herein present progressive dissection and virtual and photographic endoscopic images of the hearts without distortion. Real dissection images show us how and where to avoid this complication by indicating the true muscular component of the ventricular septum. Both virtual and photographic endoscopic images, when combined with transillumination, beautifully shows the thin wall regions and trabeculations with unprecedented clarity. We believe recognition of these anatomical nuances can reduce the likelihood of right ventricular perforation.

Very short-term tissue coverage of the CD34 antibody-covered sirolimus-eluting stent: an optical coherence tomography study

It is well known that patients with acute myocardial infarction (AMI) have delayed vessel healing despite accelerated endothelial progenitor cells (EPC) mobilization. The COMBO stent is a unique biodegradable-polymer sirolimus-eluting stent with an anti-CD34 antibody coating which captures EPC and potentially promotes vessel healing. However, there are limited data about strut tissue coverage at the very short-term period after COMBO stent implantation. This was a prospective study to investigate strut tissue coverage within 1 month after COMBO stent implantation using optical coherence tomography (OCT). Struts fully covered with tissue were defined as covered, and struts with distance from lumen surface longer than strut plus polymer thickness were defined as malapposed. Mean tissue thickness was measured only in apposed struts. A total of 8173 struts of 33 lesions in 32 patients were analyzed at an average of 19.8 ± 4.6 days after COMBO stent implantation. In lesion-level analysis, the rate of covered struts was 89.6 ± 7.2%, the rate of malapposed struts was 0.9 ± 2.0% and mean tissue thickness was 46.8 ± 14.3 µm. In comparison between AMI (n = 12) and non-AMI (n = 21) patients, there were no significant differences in the rate of covered struts (88.4 ± 8.4% vs. 90.2 ± 6.6%, p = 0.48) and mean tissue thickness (46.8 ± 13.7 µm vs. 46.9 ± 15.0 µm, p = 0.98). Multivariable analysis demonstrated that time from implantation to OCT imaging was significantly associated with mean tissue thickness. The COMBO stent had substantial tissue coverage at the very short-term period after implantation even in AMI patients, and follow-up time had an impact on vessel healing.

Targeted Pubic Neoantigen Immunotherapy Using Encapsulated Nanoparticles, Directed by Radiation

PURPOSE/OBJECTIVE(S)

We tested a treatment combining radiotherapy with pubic neoantigen nanoparticles of CAND1 and ADGRF5-II (120 ± 56 nm) in nanocapsules detectable by computed tomography (CT) (545± 24 nm) with IFN γ or PD-L1 antibody (Ab), which released their contents upon radiation exposure. We performed two radiotherapy sessions: 1) induction of MHC-I and II in tumor cells and dendritic cells (DC) by the first round of radiation with concurrently released IFN γ from nanoparticles; 2) targeted neoantigen immunotherapy with PD-L1 blockade by the second round of radiation, elicited by CAND1-specific CD8+T-cell and ADGRF5-II-specific CD4+T-cell, related to induced MHC-I and MHC-II in session 1, respectively.

MATERIALS/METHODS

For session one, nanocapsules were generated by mixing iopamiron and 15 mg IFN γ with a 1.0 mL solution containing 4.0% alginate, 3.0% hyaluronate, and 1 μg/mL P-selectin. This mixture was sprayed into 0.5 mmol/l FeCl2 supplemented with 1 µg/mL anti-VEGFR-1/2 Ab. For session two, Mixture of 110 fmol CAND1 and fmol ADGRF5-II, were encapsulated into poly lactic-co-Glycolic acid (PLGA) particle, using nanoprecitation method. Those particles were encapsulated by mixing into above alginate-hyaluronate cocktail with 400 mg PD-L1 antibody (Ab), then sprayed into 0.5 mmol/l FeCl2 supplemented with P-selectin Ab. In session one, 1 × 1010 nanocapsules were intravenously injected into BALB/c mice exhibiting primary 4TI mammary carcinoma in the left hind leg and lung metastases. Tumor accumulation was monitored by CT. Subsequently, 10 or 20 Gy 60Co γ-radiation was administered to primary tumors and lung metastasis. In session two, 1 × 1010 nanocapsules were injected i.v. and allowed to interact with P-selectin for 24 h; a further 10 or 20 Gy 60Co γ-radiation was administered to tumors and lung metastasis.

RESULTS

In session one, CT imaged the accumulation of anti-VEGFR-1/2 nanocapsules around primary and metastatic tumors, which helped determine the timing of the first radiation. The nanocapsules released P-selectin and IFN γ in response to first radiation. P-selectin was deposited on tumor vessels. Radiation and released IFN γ elicited MHC-I and II on tumor cells and DCs. In session two, released CAND1 and ADGRF5-II from PLGA particle, which were emitted from nanocapsules upon second radiation, were loaded onto MHC-I and II. Subsequently, two kinds of tertiary complex were formed on tumor cells and DC: 1) MHC-I-CAND1-CD8+T-cell receptor (TCR); and 2) MHC-II- ADGRF5-II-CD4+TCR, which destroyed tumor cells, in collaboration with released PD-L1 Ab. Those T-cell mediated cell killing was magnified via enhanced DC-mediated T-cell priming by the two kinds of tertiary complex on DC. Those treatments resulted in EF 1.5 and 86% reduction of new metastasis formation.

CONCLUSION

Our encapsulated pubic neoantigen particle will lead to quick and effective neoantigen immunotherapy.

Insights Into Interaction Between Clip Device and the Mitral Valve Apparatus in the Human Heart

Precise appreciation of the 3-dimensional relationship between the edge-to-edge clips and mitral valve apparatus remains clinically challenging. We demonstrate the images of clips observed in situ 4 years after implantation. Detailed observation from this case helps improve our understanding of 3-dimensional clinical cardiac anatomy related to transcatheter edge-to-edge mitral valve repair. (Level of Difficulty: Intermediate.).

Photogrammetry of Perfusion-Fixed Heart: Innovative Approach to Study 3-Dimensional Cardiac Anatomy

Photogrammetry generates a 3-dimensional high-resolution model from multiple 2-dimensional photographs. Herein, we demonstrate a photogrammetry of a perfusion-fixed cardiac sample around the left ventricular summit. The single photogrammetric model can be observed from almost all directions and illustrates important anatomical features for the general cardiologist. (Level of Difficulty: Advanced.).

Whole-genome sequencing analysis of molecular epidemiology and silent transmissions causing meticillin-resistant Staphylococcus aureus bloodstream infections in a university hospital

BACKGROUND

The emergence of novel genomic-type clones, such as community-associated meticillin-resistant Staphylococcus aureus (MRSA) and livestock-associated MRSA, and their invasion into hospitals have become major concerns worldwide; however, little information is available regarding the prevalence of MRSA in Japan. Whole-genome sequencing (WGS) has been conducted to analyse various pathogens worldwide. Therefore, it is important to establish a genome database of clinical MRSA isolates available in Japan.

AIM

A molecular epidemiological analysis of MRSA strains isolated from bloodstream-infected patients in a Japanese university hospital was conducted using WGS and single-nucleotide polymorphism (SNP) analysis. Additionally, through a review of patients' clinical characteristics, the effectiveness of SNP analysis as a tool for detecting silent nosocomial transmission that may be missed by other methods was evaluated in diverse settings and various time points of detection.

METHODS

Polymerase-chain-reaction-based staphylococcal cassette chromosome mec (SCCmec) typing was performed using 135 isolates obtained between 2014 and 2018, and WGS was performed using 88 isolates obtained between 2015 and 2017.

FINDINGS

SCCmec type II strains, prevalent in 2014, became rare in 2018, whereas the prevalence of SCCmec type IV strains increased from 18.75% to 83.87% of the population, and became the dominant clones. Clonal complex (CC) 5 CC8 and CC1 were detected between 2015 and 2017, with CC1 being dominant. In 88 cases, SNP analyses revealed nosocomial transmissions among 20 patients which involved highly homologous strains.

CONCLUSIONS

Routine monitoring of MRSA by whole-genome analysis is effective not only for gaining knowledge regarding molecular epidemiology, but also for detecting silent nosocomial transmission.

Data-driven cascade control system: Response estimation and controller design

In this study, we propose a data-driven design method for a cascade control system with inner and outer control loops. First, the input-output response of a controlled plant, which varies with the controller parameters of a fixed-structure inner-outer control law, is estimated directly from open-loop input-output data. Next, based on the estimated response, the controller parameters are optimized to minimize the difference between a reference model with a controlled closed-loop system. In the proposed method, the response of a fictitious reference input, which varies with the controller parameters, is estimated, and then the closed-loop response is estimated. Therefore, a closed-loop input-output data is not required, and the controller parameters are determined directly from an open-loop input-output data. Furthermore, the time constant of a reference model is also optimized so as to reduce the control error. The proposed method is compared with both conventional single-loop and cascade data-driven methods by means of numerical examples.

Clinical characteristics and outcomes of patients with chronic systemic inflammatory disease in acute myocardial infarction

BACKGROUND

Chronic systemic inflammatory diseases (CSIDs) such as rheumatoid arthritis (RA) are reportedly associated with an increased risk of ischemic cardiovascular events including acute myocardial infarction (MI). However, data are limited on clinical characteristics and ischemic and bleeding outcomes after acute MI in patients with CSIDs.

METHODS

This bi-center registry included a total of 1001 patients with acute MI undergoing percutaneous coronary intervention. CSIDs included inflammatory rheumatological conditions (RA, systemic lupus erythematosus, vasculitis, etc.) and organ-specific diseases (chronic hepatitis, psoriasis, inflammatory bowel disease, etc.). The primary endpoint was net adverse clinical events (NACE), a composite of ischemic (all-cause death, MI, and ischemic stroke) and major bleeding (Bleeding Academic Research Consortium type 3 or 5) events, during hospitalization and after discharge.

RESULTS

Of the 1001 patients, 58 (5.8%) had CSIDs. The proportion of women was higher in patients with CSIDs than those without (37.9% vs. 22.1%, p = 0.009). During the hospitalization, no significant differences in the primary endpoint of NACE were observed between patients with and without CSIDs (10.3% vs. 12.7%, p = 0.84). During the median follow-up of 42.6 months after discharge, patients with CSIDs had a higher risk of NACE (22.5% vs. 10.1%, p = 0.01) than those without, mainly driven by an increased risk of ischemic events (18.4% vs. 8.4%, p = 0.03).

CONCLUSIONS

A small but significant proportion of patients with acute MI (5.8%) had CSIDs. While the incidence of in-hospital events was similar, patients with CSIDs had worse outcomes after discharge, suggesting that further clinical investigations and therapeutic approaches are needed in this patient subset.

Bayesian design of mosaic-based mode multiplexers for various wavelength bands

Ultracompact mode multiplexers based on mosaic structure for various wavelength bands designed by Bayesian technique are investigated. C-, O-, and C + O band, TE0-TE1 2-mode multiplexers can be designed with the same footprint, by only changing the mosaic-pattern, showing the great flexibility of mosaic-based devices. Bayesian direct binary search method is used for the design, and it is demonstrated that the Bayesian technique is superior to conventional design method in terms of the best-structure search for the same number of iterations. The designed devices are fabricated for Si-waveguide platform, and the proof-of-concept results are obtained. These results indicate that the mosaic-based devices are promising candidates for future compact optical transceivers.

Design of silica-PLC LP11 mode rotator based on adiabatic mode conversion

A silica-based LP11 mode rotator, which is one of the basic and indispensable optical components for space division multiplexing, with multiple tapered trenches is proposed. Compared with the conventional interference-based LP11 mode rotator with a simple L-shape waveguide, the proposed LP11 mode rotator has many advantages in a mode conversion efficiency, an insertion loss, and a fabrication tolerance because the operation principle is based on the adiabatic mode conversion. By using an approach of the shortcut to adiabaticity, the proposed device is effectively miniaturized rather than the standard tapered structures. Among the LP11 mode rotators in the silica-based mode multi/demultiplexers, the proposed type will be a considerably promising candidate.

Dual Antithrombotic Therapy with Oral Anticoagulant and P2Y12 inhibitors in Patients with Atrial Fibrillation After Percutaneous Coronary Intervention

BACKGROUND

The efficacy and safety of dual antithrombotic therapy (DAT) with oral anticoagulant and P2Y12 inhibitors (P2Y12i) in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI) have not been well investigated. The purpose of this study was first to evaluate clinical outcomes of DAT with P2Y12i compared with triple antithrombotic therapy (TAT), and then to compare DAT with low-dose prasugrel and DAT with clopidogrel, in patients with AF undergoing PCI.

METHODS

This study was a multicenter, non-interventional, prospective and retrospective registry. A total of 710 patients with AF undergoing PCI between January 2015 and March 2021 at 15 institutions were analyzed. Clinical outcomes within 1 year, including major adverse cardiovascular events (MACE) and major bleeding events (BARC 3 or 5) were compared between patients receiving DAT (n = 239) and TAT (n = 471), and then, compared among prasugrel-DAT (n = 82), clopidogrel-DAT (n = 157), and TAT.

RESULTS

The DAT group showed significantly lower incidence of MACE and major bleeding events compared with the TAT group (log-rank p = 0.013 and 0.047). In the multivariable Cox regression analyses, DAT (p = 0.028), acute coronary syndrome (p = 0.025), and anemia (p = 0.015) were independently associated with MACE. In addition, anemia (p = 0.022) was independently associated with, and DAT (p = 0.056) and thrombocytopenia (p = 0.051) tended to be associated with, major bleeding events. When analyzed among the prasugrel-DAT, clopidogrel-DAT, and TAT groups, there were no significant differences in clinical outcomes between the prasugrel-DAT and clopidogrel-DAT groups, and similar trends were observed for both 2 groups in comparison with the TAT group.

CONCLUSIONS

In AF patients undergoing PCI, DAT was associated with lower incidence of MACE and major bleeding events compared with TAT. In comparison of P2Y12i, there might be no significant difference in the incidence of MACE and bleeding events between prasugrel-based DAT and clopidogrel-based DAT.

GC-MS analysis of exhaled gas for fine detection of inflammatory diseases

Exhaled gas analysis is a non-invasive test ideal for continuous monitoring of biological metabolic information. We analyzed the exhaled gas of patients with inflammatory diseases for trace gas components that could serve as biomarkers that enable early detection of inflammatory diseases and assessment of treatment efficacy. Furthermore, we examined the clinical potential of this method. We enrolled 34 patients with inflammatory disease and 69 healthy participants. Volatile components from exhaled gas were collected and analyzed by a gas chromatography-mass spectrometry system, and the data were examined for gender, age, inflammatory markers, and changes in markers before and after treatment. The data were tested for statistical significance through discriminant analysis by Volcano plot, Analysis of variance test, principal component analysis, and cluster analysis comparing healthy and patient groups. There were no significant differences in the trace components of exhaled gas by gender or age. However, we found differences in some components of the exhaled gas between healthy and untreated patients. In addition, after treatment, gas patterns including the patient-specific components changed to a state closer to the inflammation-free status. We identified trace components in the exhaled gas of patients with inflammatory diseases and found that some of these regressed after treatment.

Search for the Pair Production of Dark Particles X with K_{L}^{0}→XX, X→γγ

We present the first search for the pair production of dark particles X via K_{L}^{0}→XX with X decaying into two photons using the data collected by the KOTO experiment. No signal was observed in the mass range of 40-110  MeV/c^{2} and 210-240  MeV/c^{2}. This sets upper limits on the branching fractions as B(K_{L}^{0}→XX)<(1-4)×10^{-7} and B(K_{L}^{0}→XX)<(1-2)×10^{-6} at the 90% confidence level for the two mass regions, respectively.

Validation of the Domestic High Bleeding Risk Criteria for Japanese Patients with Acute Myocardial Infarction

AIMS

The Academic Research Consortium (ARC) has proposed international criteria to standardize the definition of high bleeding risk (HBR) in patients undergoing percutaneous coronary intervention (PCI). In this context, Japan has also established its own guidelines, that is, the Japanese version of HBR (J-HBR) criteria. However, the J-HBR criteria have not been fully validated, especially in patients with acute myocardial infarction (MI).

METHODS

This bi-center registry included 1079 patients with acute MI undergoing primary PCI in a contemporary setting. Patient bleeding risks were evaluated using the ARC-HBR and J-HBR criteria. The primary endpoint was rates of major bleeding events (Bleeding Academic Research Consortium type 3 or 5) at 1 year.

RESULTS

Of the 1079 patients, 505 (46.8%) and 563 (52.2%) met the ARC-HBR and J-HBR criteria, respectively. Patients who met the J-HBR criteria were found to have a higher rate of major bleeding events at 1 year than those who did not (12.8% vs. 3.3%, p＜0.001). When patients were scored and stratified using the J-HBR major and minor criteria, risks of major bleedings were progressively increased with the increase in the number of J-HBR criteria. In the receiver operating characteristic curve analysis, the ARC-HBR and J-HBR significantly predicted subsequent major bleedings after PCI, with ARC-HBR having greater predictive ability than J-HBR.

CONCLUSIONS

More than half of the patients with acute MI undergoing primary PCI in Japan met the J-HBR criteria. Although the J-HBR criteria successfully identified patients who were likely to develop major bleeding events after primary PCI, the superiority of J-HBR to ARC-HBR in predicting bleeding outcomes warrants further investigation.

Relation of GRACE Risk Score to Coronary Lipid Core Plaques in Patients with Acute Coronary Syndrome

The GRACE risk score is established to predict thrombotic events in patients with acute coronary syndrome (ACS). Although thrombotic events including myocardial infarction after ACS are mainly attributable to vulnerable plaque formation, whether the GRACE score correlates with coronary lipid-rich plaque is unclear. A total of 54 patients with ACS undergoing primary percutaneous coronary intervention under near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) guidance were included in a prospective manner. Patients were divided into two groups according to the median of the GRACE risk score. Coronary lipid plaques in the target vessel were assessed by NIRS-IVUS with lipid core burden index (LCBI) and a maximum LCBI in 4 mm (maxLCBI4mm). The receiver operating characteristics (ROC) curve analysis was performed based on the major adverse cardiovascular events as an exploratory analysis. The GRACE risk score was significantly and positively correlated with LCBI (r = 0.31, p = 0.03) and maxLCBI4mm (r = 0.38, p = 0.006). LCBI (111.7 ± 85.7 vs. 169.0 ± 83.5, p = 0.02) and maxLCBI4mm (428.5 ± 227.1 vs. 600.6 ± 227.7, p = 0.009) in the target vessel were significantly higher in the high GRACE risk score group than their counterpart. In the ROC curve analysis, LCBI and maxLCBI4mm were predictive for clinical events. In conclusion, the higher GRACE risk score may serve as a discriminator of risk comprising more lipid-rich plaques as an underlying mechanism of an increased risk of thrombotic events after ACS. In patients with ACS, the higher GRACE risk score was significantly and modestly associated with greater coronary lipid plaques in the target vessel.

Giant spin polarization and a pair of antiparallel spins in a chiral superconductor

Chiral molecules can exhibit spin-selective charge emission, which is known as chirality-induced spin selectivity^1,2. Despite the constituent light elements of the molecules, their spin polarization can approach or even exceed that of typical ferromagnets. This powerful capability may lead to applications in the chiral spintronics² field. Although the origin of spin selectivity is elusive, two microscopic phenomena have been suggested based on experimental results: effective enhancement of spin-orbit interactions³ and chirality represented by a pair of oppositely polarized spins^4,5. However, the hypotheses remain to be verified. Here we report the simultaneous observation of these two phenomena in an organic chiral superconductor by magnetoresistance measurements in the vicinity of the superconducting transition temperature. A pair of oppositely polarized spins is demonstrated by spatially mapping the spin polarity in an electric alternating current excitation. The obtained spin polarization exceeds that of the Edelstein effect^6-10 by several orders of magnitude, which indicates an effective enhancement of the spin-orbit interaction. Our results demonstrate a solid-state analogue of spin accumulations assumed for chiral molecules, and may provide clues to the origin of their molecular counterparts. In addition, the innovative capability of spin-current sourcing will invigorate superconducting spintronics research¹¹.

Prognostic Value of Natriuretic Peptide Levels and In-Hospital Heart Failure Events in Patients With Acute Myocardial Infarction

BACKGROUND

In patients with acute myocardial infarction (AMI), elevated natriuretic peptide (NP) concentrations are reportedly associated with worse clinical outcomes. This study evaluated the prognostic value of NP concentrations and in-hospital heart failure (HF) events after AMI.Methods and Results: The present bicenter registry included 600 patients with AMI undergoing percutaneous coronary intervention. HF was evaluated at 3 different time points after AMI: on admission, during hospitalization, and at the short-term follow-up at 1 month. When HF was present at each time point, 1 point was assigned to the "HF time points" (HFTP) risk scoring system; possible total scores on this system ranged from 0 to 3. The primary endpoint was a composite of all-cause death and HF rehospitalization after discharge. Among the 600 patients who survived to discharge, the primary outcome occurred in 69 (11.5%) during a mean follow-up period of 488 days. HF on admission, during hospitalization, and at the short-term follow-up were all significantly associated with subsequent clinical outcomes. Higher scores on the HFTP scoring system were related to an increased risk of the primary endpoint. Multivariable analysis indicated scores of 2 and 3 were independently associated with outcome events in a stepwise manner.

CONCLUSIONS

Among patients with AMI, HF evaluation at different time points was useful in stratifying risks of mortality and HF rehospitalization after discharge.

Expected resolution limits of x-ray free-electron laser single-particle imaging for realistic source and detector properties

The unprecedented intensity of x-ray free-electron laser sources has enabled single-particle x-ray diffraction imaging (SPI) of various biological specimens in both two-dimensional projection and three dimensions (3D). The potential of studying protein dynamics in their native conditions, without crystallization or chemical staining, has encouraged researchers to aim for increasingly higher resolutions with this technique. The currently achievable resolution of SPI is limited to the sub-10 nanometer range, mainly due to background effects, such as instrumental noise and parasitic scattering from the carrier gas used for sample delivery. Recent theoretical studies have quantified the effects of x-ray pulse parameters, as well as the required number of diffraction patterns to achieve a certain resolution, in a 3D reconstruction, although the effects of detector noise and the random particle orientation in each diffraction snapshot were not taken into account. In this work, we show these shortcomings and address limitations on achievable image resolution imposed by the adaptive gain integrating pixel detector noise.

Prognostic Factors of In-Hospital Mortality in Patients with Acute Myocardial Infarction Complicated by Cardiogenic Shock

Among patients with acute myocardial infarction (MI) complicated by cardiogenic shock (CS), in-hospital mortality remains high. In the present study, we aimed to identify factors associated with clinical outcomes of acute MI patients with CS in a contemporary setting. A total of 1102 patients with acute MI undergoing primary percutaneous coronary intervention were included, among whom 196 (17.8%) were complicated by CS. The primary outcome was all-cause death during hospitalization, and factors associated with in-hospital mortality were explored in patients with acute MI and CS. Of the 196 patients with acute MI complicated by CS, 77 (39.3%) died during hospitalization. The rates of non-ST-segment elevation MI (NSTEMI) (33.8% vs. 19.3%, p = 0.02) and culprit lesion in the left main or left anterior descending coronary artery (68.8% vs. 47.9%, p = 0.004) were higher, while left ventricular ejection fraction (LVEF) was lower (24.4 ± 11.7% vs. 39.7 ± 13.8%, p < 0.001) in non-survivors than in survivors. Multivariable analysis identified NSTEMI presentation and lower LVEF as independent predictors of in-hospital death. In conclusion, NSTEMI and low LVEF were identified as factors associated with higher in-hospital mortality. The identification of even higher-risk subsets and targeted therapeutic strategies may be warranted to improve survival of patients with acute MI and CS.

Teaching Control during the COVID-19 Pandemic

This paper aims to analyze some different solutions that were adopted in control education activities during the pandemic. The authors of this paper are educators in the control education field from different countries on all the continents, who have developed a questionnaire with the idea of collecting data about the COVID-19 pandemic impact on the control education activities. The main objective is to study the diverse alternatives that were used worldwide to perform the online educational activities during that period, such as methodologies, tools, learning management systems (LMS), theoretical exercises, laboratory experiments, types of exams, simulators, software for online lecturing, etc. As a result, comparisons between pre-and during-pandemic educational resources and methods are performed, where useful ideas and discussions are given for the control education community.

Nuclear accumulation of MLKL induces necroptosis in cardiomyocytes: potential implication in Doxorubicin-induced cardiotoxicity

Background

The treatment with doxorubicin, a powerful chemotherapeutic agent, has been shown to be associated with an increased risk of lethal heart failure. Although various types of cell death pathway such as apoptosis and ferroptosis have been shown to be involved in the development of doxorubicin-induced cardiotoxicity, DIC, the involvement of necroptosis, a novel programmed necrosis induced by translocation of activated mixed lineage kinase domain-like protein, MLKL, to plasma membrane, remains unclear.

Purpose

The aim of this study was to determine whether necroptosis is involved in the development of DIC.

Methods and results

DIC was induced in C57BL/6J mice by intraperitoneal injection of doxorubicin at a dose of 10 mg/kg 3 times for a week. Eight days after the commencement of injection, echocardiographic analyses showed that left ventricular ejection fraction assessed by echocardiography was significantly lower in the doxorubicin-treated mice than in the vehicle-treated mice (44.0±13.7 vs. 70.5±3.7%), indicating the development of DIC. Immunoblot analysis showed that MLKL protein level was higher by 1.6 fold in the doxorubicin-treated mice than in the vehicle-treated mice. Interestingly, immunohistochemical analysis showed that signals of phospho-Ser345-MLKL, an activated form of MLKL, was found in the nuclei in addition to cytosol and intercalated discs of cardiomyocytes in the doxorubicin-treated mice. To get novel insight into significance of nuclear MLKL accumulation, a leucine-rich nuclear export signal (NES) spanning amino acids 280–284 of rat MLKL was identified by site-directed mutation analyses, and H9c2 cells, cultured rat cardiomyoblasts, were transfected with expression constructs for nucleus-directed MLKL (FLAG-mtNES-MLKL) or its wild type (FLAG-WT-MLKL). Percentage of FLAG-positive cells stained with Zombie Red, a fluorescent dye that is non-permeant to live cells, was higher in FLAG-mtNES-MLKL-transfected cells than in FLAG-WT-MLKL-transfected cells (80.0±3.5% vs. 6.3±1.3%, p&lt;0.05), whereas percentage of cells immunostained with cleaved caspase-3 to FLAG-positive cells was similar in the two groups. The effect of the MLKL mutant on necroptosis was attenuated by treatment with GppNHp, an inhibitor of Ran-mediated nuclear protein import.

Conclusion

Nuclear accumulation of MLKL induces necroptosis in cardiomyocytes, which may contribute to progression of DIC.

Funding Acknowledgement

Type of funding sources: None.

Clinical trajectory and outcomes of patients with heart failure with preserved ejection fraction with normal or indeterminate diastolic function

Background

Heart failure (HF) with preserved ejection fraction (HFpEF) is a chronic and progressive disease, but limited therapeutic strategies are currently available. Although left ventricular diastolic dysfunction (DD) is a prominent mechanism of HFpEF, a certain number of patients with HFpEF have a normal diastolic function (ND) or indeterminate diastolic function (ID). With the progressive nature of HFpEF, diastolic function may change over time. However, the change of diastolic function, its predictor and prognosis in patients with clinically established HFpEF remains unknown.

Purpose

To investigate the clinical trajectory and outcomes of patients with HFpEF with ND or ID and to identify factors associated with progression from ND or ID at discharge to DD at 1-year follow-up.

Methods

Using data from a prospective multicenter observational study of patients with HFpEF, we extracted 289 patients with HFpEF with ND or ID at discharge who had echocardiographic data at 1-year follow-up for the re-evaluation of diastolic function. Diastolic function was assessed according to the 2016 American Society of Echocardiography recommendations. Patients were classified according to the absence or presence of progression from ND or ID to DD at 1 year. The primary endpoint was a composite of all-cause death and HF rehospitalization.

Results

Median age was 81 years, and 138 (47.8%) patients were female. At 1 year, 107 (37%) patients progressed to DD. During a median follow-up of 709 days, the composite endpoint occurred in 90 (31.1%) patients. Compared to patients without progression to DD, those with progression to DD had a significantly higher cumulative incidence rate of the composite endpoint (incidence rate: 11.7/100 person-year versus 23.3/100 person-year, P&lt;0.001). Progression to DD (adjusted HR: 2.014, 95% CI: 1.239–3.273, P=0.005) was independently associated with the composite endpoint. Age (adjusted OR: 1.046, 95% CI: 1.008–1.087, P=0.018), body mass index (BMI) (adjusted OR: 1.107, 95% CI: 1.029–1.192, P=0.006), and serum albumin (adjusted OR: 0.459, 95% CI: 0.216–0.974, P=0.042) were independently associated with progression from ND or ID to DD at 1 year.

Conclusion

More than one-third of patients with HFpEF with ND or ID progressed to DD at 1 year and had poor clinical outcomes. Age, BMI, and serum albumin were independently associated with this progression.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This work was supported by grants from Japan Society for the Promotion of Science KAKENHI (No. JP 17K09496) and Japan Agency for Medical Research and Development (No. JP16lk1010013).

Impact of right ventricular reserve on exercise capacity and quality of life in patients with left ventricular assist device

Background

Right heart failure following left ventricular assist device (LVAD) implantation is a major complication which significantly impairs functional capacity and quality of life (QoL). Right ventricular (RV) reserve function may limit exercise capacity and QoL in LVAD patients; however, most patients show normal RV haemodynamics at rest.

Purpose

The aim of this study was to investigate whether RV reserve assessed by the changes of RV function during exercise is correlated with exercise capacity and QoL in patients with LVAD.

Methods

We prospectively examined 20 consecutive LVAD patients who were admitted to our university hospital between June 2020 and November 2021 after excluding those who were unable to perform exercise (n=8). All patients underwent invasive exercise right heart catheterisation with simultaneous echocardiography in the supine position. RV stroke work index (RVSWI) was calculated as 0.0136 × stroke volume index × (mean pulmonary artery pressure [mPAP] − right atrial pressure [RAP]) at rest and during exercise. Exercise capacity and QoL were assessed by 6-minute walk distance (6MWD) and peak oxygen consumption (VO2) in cardiopulmonary exercise testing, and the EuroQol visual analogue scale (EQ-VAS), respectively. The patients were divided into two groups according to the median ΔRVSWI (RVSWI change from rest to peak exercise) of 1.45 (interquartile range [IQR] −0.31 to 8.25) g/m2.

Results

Patients were predominantly male (75%) and the median age was 47 (IQR 38–60) years. Patients with lower ΔRVSWI had significantly higher change on RAP (P=0.019), but significantly lower change on mPAP (P&lt;0.001) compared to those with higher ΔRVSWI. There were no significant differences in age, gender, primary aetiology of heart failure, type of LVAD devices, or echocardiographic parameters including tricuspid annular plane systolic excursion, and RVSWI at rest between the groups. ΔRVSWI during exercise were positively correlated with 6MWD (R=0.69, P&lt;0.01) and peak VO2 (R=0.66, P&lt;0.01) (Figure A). In addition, ΔRVSWI during exercise were positively correlated with the EQ-VAS (R=0.48, P=0.031). On the other hand, there was no significant correlation between RVSWI at rest and 6MWD (R=−0.11, P=0.63) and peak VO2 (R=0.13, P=0.95), and the EQ-VAS (R=0.11, P=0.61). During a median follow-up period of 312 (IQR 176–369) days, adverse events occurred in 3 patients (15%), including 1 death and 2 hospitalisations for major bleeding and right heart failure. Kaplan-Meier analysis revealed that the adverse events more frequently occurred in patients with lower ΔRVSWI compared to those with higher ΔRVSWI (Figure B).

Conclusions

ΔRVSWI was positively correlated with 6MWD, peak VO2 and EQ-VAS irrespective of RV function at rest. Our findings suggest that the assessment of RV reserve function using ΔRVSWI would be useful for risk stratification in patients with LVAD.

Funding Acknowledgement

Type of funding sources: None.

Premature atrial contraction on Holter electrocardiogram predicts the recurrence of atrial fibrillation after catheter ablation

Introduction

It is important to detect the recurrence of atrial fibrillation (AF) after catheter ablation (CA) early, but the method of detection has not been established. The purpose of this study is to determine whether 24-h Holter electrocardiogram (ECG) can predict the recurrence of AF after CA.

Methods

We studied 336 patients of 497 patients enrolled in EARNEST-PVI trial to investigate whether the total number of premature atrial contraction (PAC) and the maximum number of PAC run by 24-h Holter ECG at 6 months after CA predicted AF recurrence after 6 months. We excluded 86 patients with recurrence by 6 months after CA and 75 patients without Holter ECG at 6 months after CA.

Results

Median age was 66 years, male were 77% and median follow-up period was 1138 days. Receiver operating characteristic curve analysis identified the total number of PAC ≥270 beats and the maximum number of PAC run ≥8 beats as the optimal cutoff for prediction of AF recurrence. Kaplan-Meier analysis showed patients with the total number of PAC ≥270 beats had more frequent AF recurrence than those without (Kaplan-Meier estimated 3-year AF recurrence rate 34% vs. 17%, Log-rank P=0.001) and patients with the maximum number of PAC run ≥8 beats had more frequent AF recurrence than those without (Kaplan-Meier estimated 3-year AF recurrence rate 33% vs. 20%, Log-rank P=0.006). Multivariate analysis revealed that the total number of PAC ≥270 beats and the maximum number of PAC run were significantly associated with AF recurrence (hazard ratio [95% confidence interval] 1.83 [1.16–2.91], P=0.01 and 1.01 [1.01–1.02], P=0.001, respectively)

Conclusion

The total number of PAC and the maximum number of PAC run on the Holter ECG may be useful in predicting AF recurrence after CA.

Funding Acknowledgement

Type of funding sources: None.

Evaluation of the direct protective effects of Canagliflozin on the Isoproterenol-induced cell injury in rat cardiomyocytes

Background

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are agents that act by inhibiting glucose and sodium reabsorption in the proximal renal tubule which promotes urinary glucose excretion. More recently, significant benefit data of SGLT2 inhibitors in patients with heart failure, independent of the presence of type 2 diabetes has been reported. We have previously demonstrated that Canagliflozin (Cana), a SGLT2 inhibitor, reduced the ventricular effective refractory period in isoproterenol (ISP)-induced myocardial injury rat model accompanied with the suppression of reactive oxygen species and the elevation of ketone bodies, suggesting the effect of Cana on electrical cardiac remodeling. The direct effect of Cana to the cardiomyocytes and its underlying molecular mechanism was remained to be clarified. We therefore established an ISP-induced neonatal rat ventricular cardiomyocyte (NRVCM) in vitro model, pretreated with Cana and/or ketone bodies.

Methods

Primary NRVCM were isolated from Wistar rats, were pretreated by Cana with or without βOHB (the most abundant ketone body in circulation), followed by a stimulation of ISP (10μM). Cells without drug or ketone body pretreatment were used as control. We then analyzed its effect on cell viability, apoptosis, and mitochondrial membrane potential using MTT assay, TUNEL assay, and mitochondrial membrane potential assay, respectively. MTT assay was also performed with or without PI3k inhibitor, LY294002. The end-labeling of DNA fragmentation were labelled with FITC, followed by the nuclei counterstain with DAPI and were observed with confocal microscope. The apoptotic index was defined as the percentage of TUNEL positive cells / total nuclei.

Results

Cana rescued the reduction of NRVCM cell viability induced by ISP stimulation for 24 hours which was inhibited by LY294002 compared to cells without pretreatment. Interestingly, pretreatment of βOHB with or without Cana improved also the NRCVM cell viability whereas there was no significant difference between these two conditions or with cells treated with Cana only, suggesting the direct protective effect of Cana. In 48 hours of ISP stimulation, the apoptotic index intends to decrease in Cana and/or βOHB compared to cells without pretreatment (Figure 1). Although the mitochondrial function was maintained in Cana-pretreated cells compared to cells without pretreatment, there was no significant difference in βOHB-pretreated cells.

Conclusions

Cana has a direct protective effect on cardiomyocytes cell viability, apoptosis as well as the mitochondrial function impaired by ISP through the cell survival signaling PI3K/Akt pathway. This brings a new insight to the therapeutic target of cardiovascular disease.

Funding Acknowledgement

Type of funding sources: None.