Forecasting the Acute Heart Failure Admissions: Development of Deep Learning Prediction Model Incorporating the Climate Information.

BACKGROUND: Climate is known to influence the incidence of cardiovascular events. However, their prediction with traditional statistical models remains imprecise. METHODS AND RESULTS: We analyzed 27,799 acute heart failure (AHF) admissions within the Tokyo CCU Network Database from January 2014 to December 2019. High-risk AHF (HR-AHF) day was defined as a day with the upper 10th percentile of AHF admission volume. Deep neural network (DNN) and traditional regression models were developed using the admissions in 2014-2018 and tested in 2019. Explanatory variables included 17 meteorological parameters. Shapley additive explanations were used to evaluate their importance. The median number of incidences of AHF was 12 (9-16) per day in 2014-2018 and 11 (9-15) per day in 2019. The predicted AHF admissions correlated well with the observed numbers (DNN: R2 = 0.413, linear regression: R2 = 0.387). The DNN model was superior in predicting HR-AHF days compared with the logistic regression model [c-statistics: 0.888 (95% CI: 0.818-0.958) vs 0.827 (95% CI: 0.745-0.910): P = .0013]. Notably, the strongest predictive variable was the 7-day moving average of the lowest ambient temperatures. CONCLUSIONS: The DNN model had good prediction ability for incident AHF using climate information. Forecasting AHF admissions could be useful for the effective management of AHF.

Timing of Worsening Renal Function in Patients Hospitalized for Heart Failure Exacerbation Who Were Being Treated With Intravenous Diuretic Therapy.

BACKGROUND: This retrospective observational study investigated the incidence of worsening renal function (WRF) in patients hospitalized for heart failure (HF) and treated with intravenous diuretics in Japan.Methods and Results: Associations between WRF at any point and HF treatments, and the effects of WRF on outcomes were evaluated (Diagnosis Procedure Combination database). Of 1,788 patients analyzed (mean [±SD] age 80.5±10.2 years; 54.4% male), 641 (35.9%) had WRF during a course of hospitalization for worsening HF: 208 (32.4%) presented with WRF before admission (BA-WRF; estimated glomerular filtration rate decreased by ≥25% from baseline at least once between 30 days prior to admission and admission); 44 (6.9%) had WRF that persisted before and after admission (P-WRF); and 389 (60.7%) had WRF develop after admission (AA-WRF). Delayed initial diuretic administration, higher maximum doses of intravenous diuretics during hospitalization, and diuretic readministration during hospitalization were associated with a significantly higher incidence of AA-WRF. Patients with WRF at any time point were at higher risk of death during hospitalization compared with patients without WRF, with adjusted hazard ratios of 3.56 (95% confidence interval [CI] 2.23-5.69) for BA-WRF, 3.23 (95% CI 2.21-4.71) for AA-WRF, and 13.16 (95% CI 8.19-21.15) for P-WRF (all P<0.0001). CONCLUSIONS: Forty percent of WRF occurred before admission for acute HF; there was no difference in mortality between patients with BA-WRF and AA-WRF.

Myocardial Injury by COVID-19 Infection Assessed by Cardiovascular Magnetic Resonance Imaging　- A Prospective Multicenter Study.

BACKGROUND: This prospective multicenter study assessed the prevalence of myocardial injury in patients with COVID-19 using cardiac magnetic resonance imaging (CMR).Methods and Results: We prospectively screened 505 patients with moderate to severe COVID-19 disease from 7 hospitals in Japan. Of these patients, 31 (mean [±SD] age 63.5±10.4 years, 23 [74%] male) suspected of myocardial injury, based on elevated serum troponin or B-type natriuretic peptide concentrations either upon admission or 3 months after discharge, underwent CMR 3 months after discharge. The primary endpoint was the presence of myocardial injury, defined by any of the following: (1) contrast enhancement in the left or right ventricle myocardium on late gadolinium enhancement CMR; (2) left or right ventricular dysfunction (defined as <50% and <45%, respectively); and (3) pericardial thickening on contrast enhancement. The mean (±SD) duration between diagnosis and CMR was 117±16 days. The primary endpoint was observed in 13 of 31 individuals (42%), with 8 (26%) satisfying the modified Lake Louise Criteria for the diagnosis of acute myocarditis. CONCLUSIONS: This study revealed a high incidence of myocardial injury identified by CMR in patients with moderate to severe COVID-19 and abnormal findings for cardiac biomarkers.

Conditional deletion of IκBζ in hematopoietic cells promotes functional recovery after spinal cord injury in mice.

BACKGROUND: Transcription factor protein IκBζ (encoded by the Nfkbiz gene) regulates nuclear factor-κB (NF-κB) and is involved in the pathophysiology of various inflammatory diseases. However, the role of IκBζ in secondary damage following spinal cord injury (SCI) remains to be determined. Here, we investigated the effect of IκBζ expressed in hematopoietic cells on the progression of secondary damage and functional recovery after SCI. METHODS: We used conditional IκBζ-knockout mice (Mx1-Cre;Nfkbizfl/f) to examine the role of IκBζ in hematopoietic cells after SCI. Contusion SCI was induced using a force of 60 kdyn. The recovery of locomotor performance was evaluated using the nine-point Basso Mouse Scale (BMS) until 42 days post-injury. Expression patterns of inflammatory cytokines and chemokines were examined by quantitative real-time PCR or proteome array analysis. Bone marrow transplantation (BMT) was performed to eliminate the effect of IκBζ deletion in non-hematopoietic cells. RESULTS: Mx1-Cre;Nfkbizfl/fl mice had significantly improved locomotor function compared with wild-type (WT) mice. The mRNA expression of Nfkbiz in WT mice peaked at 12 h after SCI and then decreased slowly in both the spinal cord and white blood cells. In situ hybridization showed that Nfkbiz mRNA was localized in cell nuclei, including macrophage-like cells, in the injured spinal cord of WT mice at 1 day after SCI. Compared with WT mice, Mx1-Cre;Nfkbizfl/fl mice had significantly increased mRNA expressions of interleukin (Il)-4 and Il-10 in the injured spinal cord. In addition, Mx1-Cre;Nfkbizfl/fl mice had significantly higher protein levels of granulocyte-macrophage colony-stimulating factor and C-C motif chemokine 11 compared with WT mice. BMT from Mx1-Cre;Nfkbizfl/fl mice into WT mice improved functional recovery after SCI compared with control mice (WT cells into WT mice). CONCLUSIONS: IκBζ deletion in hematopoietic cells improved functional recovery after SCI, possibly by shifting the inflammatory balance towards anti-inflammatory and pro-regenerative directions.

Catheter ablation for patients with atrial fibrillation and heart failure with reduced and preserved ejection fraction: insights from the KiCS-AF multicentre cohort study.

AIMS: The usefulness of catheter ablation (CA) for atrial fibrillation (AF) across a broad spectrum of heart failure (HF) patients remains to be established. We assessed the association of CA with both health-related quality of life (QoL) and cardiovascular events among HF patients with reduced and preserved left ventricular ejection fraction (LVEF) in an 'all-comer' outpatient-based AF registry. METHODS AND RESULTS: Of 3303 patients with AF consecutively enrolled in a retrospective multicentre registry that mandated the Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) questionnaire at registration and 1-year follow-up, we extracted data from 530 patients complicating clinical HF. The association between CA and both 1-year change in AFEQT Overall Summary (AFEQT-OS) scores and 2-year composite clinical outcomes (including all-cause death, stroke, and HF hospitalization) was assessed by multivariable analyses. The median duration of AF was 108 days (52-218 days), and 83.4% had LVEF >35%. Overall, 75 patients (14.2%) underwent CA for AF within 1-year after registration. At 1-year follow-up, 67.2% in the ablation group showed clinically meaningful improvements of ≥ 5 points in AFEQT-OS score than 47.8% in the non-ablation group {adjusted odds ratio, 2.03 [95% confidence interval (CI): 1.13-3.64], P = 0.017}. Furthermore, the composite endpoint of all-cause death, stroke, and HF hospitalization occurred less frequently in the ablation group than the non-ablation group [adjusted hazard ratio, 0.27 (95% CI: 0.09-0.86), P = 0.027]. CONCLUSION: Among AF-HF patients, CA was associated with improved QoL and lower risk of cardiovascular events against drug therapy alone, even for patients with mildly reduced and preserved LVEF.

Improved prediction of sudden cardiac death in patients with heart failure through digital processing of electrocardiography.

AIMS: Available predictive models for sudden cardiac death (SCD) in heart failure (HF) patients remain suboptimal. We assessed whether the electrocardiography (ECG)-based artificial intelligence (AI) could better predict SCD, and also whether the combination of the ECG-AI index and conventional predictors of SCD would improve the SCD stratification among HF patients. METHODS AND RESULTS: In a prospective observational study, 4 tertiary care hospitals in Tokyo enrolled 2559 patients hospitalized for HF who were successfully discharged after acute decompensation. The ECG data during the index hospitalization were extracted from the hospitals' electronic medical record systems. The association of the ECG-AI index and SCD was evaluated with adjustment for left ventricular ejection fraction (LVEF), New York Heart Association (NYHA) class, and competing risk of non-SCD. The ECG-AI index plus classical predictive guidelines (i.e. LVEF ≤35%, NYHA Class II and III) significantly improved the discriminative value of SCD [receiver operating characteristic area under the curve (ROC-AUC), 0.66 vs. 0.59; P = 0.017; Delong's test] with good calibration (P = 0.11; Hosmer-Lemeshow test) and improved net reclassification [36%; 95% confidence interval (CI), 9-64%; P = 0.009]. The Fine-Gray model considering the competing risk of non-SCD demonstrated that the ECG-AI index was independently associated with SCD (adjusted sub-distributional hazard ratio, 1.25; 95% CI, 1.04-1.49; P = 0.015). An increased proportional risk of SCD vs. non-SCD with an increasing ECG-AI index was also observed (low, 16.7%; intermediate, 18.5%; high, 28.7%; P for trend = 0.023). Similar findings were observed in patients aged ≤75 years with a non-ischaemic aetiology and an LVEF of >35%. CONCLUSION: To improve risk stratification of SCD, ECG-based AI may provide additional values in the management of patients with HF.

Initiation and Up-Titration of Guideline-Based Medications in Hospitalized Acute Heart Failure Patients　- A Report From the West Tokyo Heart Failure Registry.

BACKGROUND: Despite recommendations from clinical practice guidelines to initiate and titrate guideline-directed medical therapy (GDMT) during their hospitalization, patients with acute heart failure (AHF) are frequently undertreated. In this study we aimed to clarify GDMT implementation and titration rates, as well as the long-term outcomes, in hospitalized AHF patients.Methods and Results: Among 3,164 consecutive hospitalized AHF patients included in a Japanese multicenter registry, 1,400 (44.2%) with ejection fraction ≤40% were analyzed. We assessed GDMT dosage (ß-blockers, renin-angiotensin inhibitors, and mineralocorticoid-receptor antagonists) at admission and discharge, examined the contributing factors for up-titration, and evaluated associations between drug initiation/up-titration and 1-year post-discharge all-cause death and rehospitalization for HF via propensity score matching. The mean age of the patients was 71.5 years and 30.7% were female. Overall, 1,051 patients (75.0%) were deemed eligible for GDMT, based on their baseline vital signs, renal function, and electrolyte values. At discharge, only 180 patients (17.1%) received GDMT agents up-titrated to >50% of the maximum titrated dose. Up-titration was associated with a lower risk of 1-year clinical outcomes (adjusted hazard ratio: 0.58, 95% confidence interval: 0.35-0.96). Younger age and higher body mass index were significant predictors of drug up-titration. CONCLUSIONS: Significant evidence-practice gaps in the use and dose of GDMT remain. Considering the associated favorable outcomes, further efforts to improve its implementation seem crucial.

Perspectives of hospitalized heart failure patients: preferred and perceived participation roles in treatment decisions.

Shared decision-making (SDM) is a pivotal process in seeking optimal individual treatment and incorporating clinical evidence and patients' autonomous preferences. However, patients' actual attitudes toward participation in decision-making for state-of-the-art heart failure (HF) treatment remain unclear. We conducted a questionnaire-based survey distributed by nurses and physicians specializing in HF care to assess patients' preferred and perceived participation roles in treatment decision-making during the index hospitalization, rated on five scales (from extremely passive to purely autonomous attitudes). Simultaneously, we investigated the important factors underlying treatment decision-making from the perspective of hospitalized HF patients. Of the 202 patients who were approached by our multidisciplinary HF team between 2017 and 2020, 166 (82.2%) completed the survey. Logistic regression analyses were conducted to identify the clinical determinants of patients who reported that they left all decisions to physicians (i.e., extremely passive attitude). Of the 166 participants (male 67.5%, median age 73 years), 32.5% preferred an extremely passive attitude, while 61.4% reported that they actually chose an extremely passive attitude. A sole determinant of choosing an extremely passive decision-making role was lower educational status (odds ratio: 2.11, 95% confidence interval 1.11-4.00). The most important factor underlying the decision-making was "Physician recommendation" (89.2%). Notably, less than 50% considered "In alignment with my values and preferences" as an important factor underlying treatment decision-making. The majority of HF patients reported that they chose an extremely passive approach, and patients prioritized physician recommendation over their own values and preferences.

Development and initial performance of a miniature axial flow blood pump using magnetic fluid shaft seal.

In this study, we developed a new catheter-mounted micro-axial flow blood pump (MFBP) using a new miniature magnetic fluid shaft seal (MFSS). The prototype of the catheter-mounted MFBP had a maximum diameter of 8 mm and a length of 50 mm. The new MFSS composed a neodymium magnet ring, an iron ring, and a magnetic fluid particularly designed for the MFSS. The new MFSS had outer and inner diameters of 4.0 mm and 2.6 mm, respectively, and a length of 3.0 mm. The sealing pressure of the MFSS was calculated to be 432 mmHg using FEM (Finite Element Method) result; therefore, the MFSS had sufficient sealing pressure for the catheter-mounted MFBP. The friction loss of the MFSS included the friction owing to the viscosity of the magnetic fluid and the magnetic force between the iron ring and ring magnet. The total friction loss of the MFSS was 0.08-0.09 W in the pump operational speed range from 22,000 to 35,000 rpm. From the in vitro experimental results, the catheter-mounted MFBP using the MFSS had a pump output of 3 L/min. against a differential pressure of 60 mmHg, and the pump characteristics of the MFBP were almost the same as those of Impella 5.0.

Ossification of the anterior longitudinal ligament affects the severity and distribution of neurological deficits following spinal cord injury without radiological abnormality.

BACKGROUND: The incidence of spinal cord injury without radiological abnormality (SCIWORA) is increasing among older adults in developed countries. SCIWORA is commonly associated with ossification of the spinal ligament, specifically the ossification of the posterior longitudinal ligament (OPLL) and ossification of the anterior longitudinal ligament (OALL). OALL induces segmental spinal fusion and alters the biomechanical properties of the cervical spine; however, whether OALL modulates the severity of SCIWORA remains unknown. This study aimed to investigate the influence of OALL on the severity and distribution of neurological deficits following SCIWORA. METHODS: This retrospective study included 122 patients with SCIWORA who were admitted to our hospital from April 2008 to March 2022. The neurological function of all the included patients was assessed via the American Spinal Injury Association (ASIA) Impairment Scale (AIS) at admission. Magnetic resonance imaging (MRI) and computed tomography were performed within 48 h of trauma. Central cord syndrome (CCS) was defined as the upper-extremity ASIA motor score being at least 10 points lesser than the lower-extremity motor score. RESULTS: The study included 122 patients with a mean age of 65.1 years. Comparing mild (AIS grades C or D) and severe (AIS grades A or B) neurological deficits revealed that the former was independently associated with ground-level falls, OALL, and absence of prevertebral T2 high-intensity area on MRI. Although 39% of patients with SCIWORA exhibited OPLL as an etiology of cervical stenosis, OPLL demonstrated no significant effect on the severity of neurological deficits. CCS occurrence was independently associated with OALL and a larger cross-sectional cord area on MRI. Patients with OALL had significantly higher lower-extremity ASIA motor scores than those without OALL. CONCLUSIONS: OALL was significantly associated with mild neurological deficits in the lower extremities and with the occurrence of CCS after SCIWORA.

Sleep-disordered breathing is independently associated with elevated natriuretic peptide levels in patients with cardiovascular diseases.

Sleep disorders and sleep duration have attracted considerable attention as potential modifiable risk factors for the development and progression of heart failure (HF). However, whether these sleep behaviors could aggravate the underlying cardiac condition remains ambiguous. We evaluated the associations between the levels of plasma B-type natriuretic peptide (BNP) and sleep-disordered breathing (SDB), sleep quality and quantity, or daytime sleepiness in cardiovascular diseases (CVD) patients. A total of 1717 consecutive patients with CVD [median age, 66 years (55-74 years); female, 27.5%] were enrolled. SDB was screened by nocturnal pulse oximetry; sleep quality and quantity were determined by Pittsburg Sleep Quality Index, and daytime sleepiness was examined by Epworth Sleepiness Scale. The median plasma BNP level was 54.9 pg/ml (23.5-146.4 pg/ml). Multiple regression analyses showed that the BNP level in the highest quintile (BNP > 181.8 pg/ml) was associated with SDB (severe: OR, 5.88; 95% CI 3.17-10.88; moderate: OR, 3.62; 95% CI 2.17-6.02; mild: OR, 2.22: 95% CI 1.42-3.47). There were no significant associations between other sleep parameters and higher BNP levels. The relationship between SDB and BNP levels was unchanged regardless of the previous history of symptomatic HF. SDB was independently associated with the elevated plasma BNP level in patients with a variety of CVD.

Sex differences in sleep and psychological disturbances among patients admitted for cardiovascular diseases.

BACKGROUND: Understanding sex differences is critical for improving outcomes in patients with cardiovascular conditions. Sleep and psychological disturbances contribute to the development and progression of cardiovascular diseases, and important sex differences persist in their incidence and association with clinical outcomes. METHODS: Sex-based variation in sleep and psychological disturbances were assessed in consecutive patients with cardiovascular diseases in a single university hospital. The prevalence of insomnia, sleep disordered breathing (SDB), anxiety, and depression was assessed using the Pittsburgh Sleep Quality Index (PSQI), nocturnal pulse oximeter, and the Hospital Anxiety and Depression Scale (HADS). The effect of sex on the prevalence of sleep and psychological disturbances as well as their associations was quantified using multivariate logistic regression models. RESULTS: Among 1,233 patients (mean age 63.6 years, 25% women), women were significantly less likely than men to experience SDB (17.5% vs 31.5%, p < 0.001), but more likely to report an increased burden of insomnia (54.7% vs 43.3%, p = 0.001) and depression (23.9% vs 16.7%, p = 0.004). Insomnia was associated with depression, which was more remarkable among women (p value for interaction: 0.039). SDB was associated with anxiety among women but not men (p value for interaction: 0.003). There was no significant difference in the prevalence of anxiety between women and men. CONCLUSIONS: Among patients with cardiovascular disease, women reported an increased burden of insomnia and depression compared to men. The association between sleep and psychological disturbances may be more pronounced in women, suggesting that cardiologists should increase efforts for identification of such comorbidities and administer corresponding treatment, especially in women.

The impact of diabetes mellitus on spinal fracture with diffuse idiopathic skeletal hyperostosis: A multicenter retrospective study.

BACKGROUND: Patients with diffuse idiopathic skeletal hyperostosis (DISH) are susceptible to spinal column injuries with neurological deterioration. Previous studies indicated that the prevalence of diabetes mellitus (DM) in patients with DISH was higher than that in patients without DISH. This study investigates the impact of DM on surgical outcomes for spinal fractures in patients with DISH. METHODS: We retrospectively evaluated 177 spinal fractures in patients with DISH (132 men and 45 women; mean age, 75 ± 10 years) who underwent surgery from a multicenter database. The subjects were classified into two groups according to the presence of DM. Perioperative complications, neurological status by Frankel grade, mortality rate, and status of surgical site infection (SSI) were compared between the two groups. RESULTS: DM was present in 28.2% (50/177) of the patients. The proportion of men was significantly higher in the DM group (DM group: 86.0% vs. non-DM group: 70.1%) (p = 0.03). The overall complication rate was 22.0% in the DM group and 19.7% in the non-DM group (p = 0.60). Poisson regression model revealed that SSI was significantly associated with DM (DM group: 10.0% vs. non-DM group: 2.4%, Relative risk: 4.5) (p = 0.048). Change in neurological status, mortality rate, instrumentation failure, and nonunion were similar between both groups. HbA1c and fasting blood glucose level (SSI group: 7.2% ± 1.2%, 201 ± 67 mg/dL vs. non-SSI group: 6.6% ± 1.1%, 167 ± 47 mg/dL) tended to be higher in patients with SSI; however, there was no significant difference. CONCLUSIONS: In spinal fracture in patients with DISH, although DM was an associated factor for SSI with a relative risk of 4.5, DM did not negatively impact neurological recovery. Perioperative glycemic control may be useful for preventing SSI because fasting blood glucose level was high in patients with SSI.

Impact of Left Ventricular Chamber Size on Outcome in Heart Failure with Preserved Ejection Fraction.

Although heart failure with preserved ejection fraction (HFpEF) has a highly variable phenotype, heterogeneity in left ventricular chamber size (LVCS) and its association with long-term outcome have not been thoroughly investigated. The present study sought to determine the impact of LVCS on clinical outcome in HFpEF.A total of 1505 consecutive HFpEF patients admitted to hospitals in the multicenter WET-HF Registry for acute decompensated HF (ADHF) between 2006 and 2017 were analyzed. The patients (age: 80 [73-86], male: 48%) were divided into larger (L) or smaller (S) LV end-diastolic diameter (LVEDD) groups by the median value 45 mm.Younger age, male sex, higher body mass index, more favorable nutritional status, valvular etiology, and lower LVEF were associated with larger LVEDD. After propensity matching (399 pairs), the L group showed a larger left atrial diameter, E/e', and tricuspid regurgitation pressure gradient and greater severity of mitral regurgitation. The L group had a higher rate of composite endpoint of all-cause death and ADHF re-admission (P = 0.021) and was an independent predictor. On the other hand, in the pre-matched cohort, the S group rather showed higher in-hospital (4% versus 2%. P = 0.004) and post-discharge mortality (P = 0.009).In HFpEF, LVCS was affected by demographic and cardiac parameters. After adjustment for demographic parameters, larger LVCS was associated with worse clinical outcome. Higher mortality in the S group in the pre-matched cohort might be related to the demographic factors suggesting frailty and/or sarcopenia.

Prognostic Understanding and Preference for the Communication Process with Physicians in Hospitalized Heart Failure Patients.

BACKGROUND: Heart failure (HF) is a highly prevalent, heterogeneous, and life-threatening condition. Precise prognostic understanding is essential for effective decision making, but little is known about patients' attitudes toward prognostic communication with their physicians. METHODS AND RESULTS: We conducted a questionnaire survey, consisting of patients' prognostic understanding, preferences for information disclosure, and depressive symptoms, among hospitalized patients with HF (92 items in total). Individual 2-year survival rates were calculated using the Seattle Heart Failure Model, and its agreement level with patient self-expectations of 2-year survival were assessed. A total of 113 patients completed the survey (male 65.5%, median age 75.0 years, interquartile range 66.0-81.0 years). Compared with the Seattle Heart Failure Model prediction, patient expectation of 2-year survival was matched only in 27.8% of patients; their agreement level was low (weighted kappa = 0.11). Notably, 50.9% wished to know "more," although 27.7% felt that they did not have an adequate prognostic discussion. Compared with the known prognostic variables (eg, age and HF severity), logistic regression analysis demonstrated that female and less depressive patients were associated with patients' preference for "more" prognostic discussion. CONCLUSIONS: Patients' overall prognostic understanding was suboptimal. The communication process requires further improvement for patients to accurately understand their HF prognosis and be involved in making a better informed decision.

Development and accuracy evaluation of a degree of occlusion visualization system for roller pumps used in cardiopulmonary bypass.

In roller pumps used for cardiopulmonary bypass (CPB), the degree of blockage within the tube resulting from compression of the tube by the rollers, or the degree of occlusion, is closely related to hemolysis, with both tight occlusive and non-occlusive degrees promoting hemolysis. There are as yet no international standards regarding methods of adjusting occlusiveness, and the amount of mechanical stress exerted upon blood remains unknown. To prevent hemolysis during CPB using roller pumps, there is a need to clarify and quantitatively assess the mechanical stress of the occlusiveness of the roller pump. In this study, we have developed a degree of occlusion quantification system which constructs the flow channel shape within an occluded tube from red optical density images, and we have verified the validity of this system. Utilizing a linear actuator, an acrylic roller and raceway, a solution colored with simulated blood powder, and a 3/8-inch vinyl chloride tube, this system uses a camera to capture red optical density images within an occluded tube and constructs the tube flow channel shape using a formula manipulation system. To verify the accuracy of this system, we compared the thickness of a cross-section of the flow channel constructed with the degree of occlusion quantification system with the thickness of a cross-section of silicone cured under the same occlusion conditions. Our experiments indicated that for areas with a small tube gap, this system can construct highly accurate three-dimensional shapes and obtain quantitative indicators assessing the degree of occlusion.

Hemolysis and von Willebrand factor degradation in mechanical shuttle shear flow tester.

Chronic blood trauma caused by the shear stresses generated by mechanical circulatory support (MCS) systems is one of the major concerns to be considered during the development of ventricular assist devices. Large multimers with high-molecular-weight von Willebrand factor (VWF) are extended by the fluid forces in a shear flow and are cleaved by ADAMTS13. Since the mechanical revolving motions in artificial MCSs induce cleavage in large VWF multimers, nonsurgical bleeding associated with the MCS is likely to occur after mechanical hemodynamic support. In this study, the shear stress (~ 600 Pa) and exposure time related to hemolysis and VWF degradation were investigated using a newly designed mechanical shuttle shear flow tester. The device consisted of a pair of cylinders facing the test section of a small-sized pipe; both the cylinders were connected to composite mechanical heads with a sliding-sleeve structure for axial separation during the withdrawing motion. The influence of exposure time, in terms of the number of stress cycles, on hemolysis and VWF degradation was confirmed using fresh goat blood, and the differences in the rates of dissipation of the multimers were established. The plasma-free hemoglobin levels showed a logarithmic increase corresponding to the number of cycles, and the dissipation of large VWF multimers occurred within a few seconds under high shear stress flow conditions.

Deletion of inflammasome adaptor protein ASC enhances functional recovery after spinal cord injury in mice.

BACKGROUND: Research has revealed the crucial roles of inflammasomes in various central nervous system disorders. However, the role of inflammasomes in secondary damage following spinal cord injury (SCI) remains incompletely understood. METHODS: Here, we investigated the role of apoptosis-associated speck-like protein (ASC), an adaptor protein for inflammasome formation, after contusion SCI in ASC homozygous knockout (ASC-/-) mice. Contusion SCI was induced using a force of 60 kdyn, and recovery of open-field locomotor performance was evaluated using the nine-point Basso Mouse Scale (BMS). Bone marrow transplantation (BMT) was performed to create mice chimeric for ASC expression in bone marrow cells. RESULTS: Western blot analysis revealed that protein expression of NLRP3, ASC, Caspase-1, and IL-ß were increased in injured spinal cords compared with sham-control spinal cords at 1 day post injury (dpi). Double immunostaining showed that ASC expression was co-localized to cellular constituents of the spinal cord, including NeuN+ neurons, CD11b+ microglia/macrophages, GFAP+ astrocytes, and MOG+ oligodendrocytes. ASC-/- mice had significantly better locomotor function assessed by BMS than wild-type (WT) mice. ASC-/- mice also had significantly reduced levels of Nlrp3, Casp1, IL1b, Il-6, Tnfa, Cxcl1, and Ly6g mRNA compared with WT mice. BMT (WT→ASC-/-) mice had significantly better BMS scores than BMT (WT→WT) mice. BMT (ASC-/-→WT) mice also had significantly better BMS scores than BMT (WT→WT) mice. However, the statistical significance was limited to time points between 7 and 21 dpi. CONCLUSIONS: These results suggest that ASC-dependent inflammasome formation, especially in resident cells of the spinal cord, plays a pivotal role in the progression of secondary damage following SCI.

Risk factors for delayed diagnosis of spinal fracture associated with diffuse idiopathic skeletal hyperostosis: A nationwide multiinstitution survey.

BACKGROUND: Patients with DISH are susceptible to spinal fractures and subsequent neurological impairment, including after minor trauma. However, DISH is often asymptomatic and fractures may have minimal symptoms, which may lead to delayed diagnosis. The purpose of this study was to identify risk factors for delayed diagnosis of spinal fractures in patients with diffuse idiopathic skeletal hyperostosis (DISH). METHODS: The subjects were 285 patients with DISH surgically treated at 18 medical centers from 2005 to 2015. Cause of injury, imaging findings, neurological status at the times of injury and first hospital examination, and the time from injury to diagnosis were recorded. A delayed diagnosis was defined as that made >24 h after injury. RESULTS: Main causes of injury were minor trauma due to a fall from a standing or sitting position (51%) and high-energy trauma due to a fall from a high place (29%) or a traffic accident (12%). Delayed diagnosis occurred in 115 patients (40%; 35 females, 80 males; mean age 76.0 ± 10.4 years), while 170 (60%; 29 females, 141 males; mean age 74.6 ± 12.8 years) had early diagnosis. Delayed group had a significantly higher rate of minor trauma (n = 73, 63% vs. n = 73, 43%), significantly more Frankel grade E (intact neurological status) cases at the time of injury (n = 79, 69% vs. n = 73, 43%), and greater deterioration of Frankel grade from injury to diagnosis (34% vs. 8%, p < 0.01). In multivariate analysis, a minor trauma fall (OR 2.08; P < 0.05) and Frankel grade E at the time of injury (OR 2.29; P < 0.01) were significantly associated with delayed diagnosis. CONCLUSION: In patients with DISH, it is important to keep in mind the possibility of spinal fracture, even in a situation in which patient sustained only minor trauma and shows no neurological deficit. This is because delayed diagnosis of spinal fracture can cause subsequent neurological deterioration.

Prediction of sudden cardiac death in Japanese heart failure patients: international validation of the Seattle Proportional Risk Model.

AIMS: Heart failure (HF) is associated with an increased risk of sudden cardiac death (SCD). This study sought to demonstrate the incidence of SCD within a multicentre Japanese registry of HF patients hospitalized for acute decompensation, and externally validate the Seattle Proportional Risk Model (SPRM). METHODS AND RESULTS: We consecutively registered 2240 acute HF patients from academic institutions in Tokyo, Japan. The discrimination and calibration of the SPRM were assessed by the c-statistic, Hosmer-Lemeshow statistic, and visual plotting among non-survivors. Patient-level SPRM predictions and implantable cardioverter-defibrillator (ICD) benefit [ICD estimated hazard ratio (HR), derived from the Cox proportional hazards model in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)] was calculated. During the 2-year follow-up, 356 deaths (15.9%) occurred, which included 76 adjudicated SCDs (3.4%) and 280 non-SCDs (12.5%). The SPRM showed acceptable discrimination [c-index = 0.63; 95% confidence interval (CI) 0.56-0.70], similar to that of original SPRM-derivation cohort. The calibration plot showed reasonable conformance. Among HF patients with reduced ejection fraction (EF; < 40%), SPRM showed improved discrimination compared with the ICD eligibility criteria (e.g. New York Heart Association functional Class II-III with EF ≤ 35%): c-index = 0.53 (95% CI 0.42-0.63) vs. 0.65 (95% CI 0.55-0.75) for SPRM. Finally, in the subgroup of 246 patients with both EF ≤ 35% and SPRM-predicted risk of ≥ 42.0% (SCD-HeFT defined ICD benefit threshold), mean ICD estimated HR was 0.70 (30% reduction of all-cause mortality by ICD). CONCLUSION: The cumulative incidence of SCD was 3.4% in Japanese HF registry. The SPRM performed reasonably well in Japanese patients and may aid in improving SCD prediction.