Benefit of prehospital electrocardiogram on door-to-device time in ST-segment elevation myocardial infarction with cardiogenic shock: Data from the Kanagawa acute cardiovascular registry.

BACKGROUND: The benefit of prehospital 12­lead electrocardiogram (PH-ECG) performed by emergency medical service personnel at the site of first medical contact (FMC) in patients with ST-segment elevation myocardial infarction (STEMI) with cardiogenic shock (CS-STEMI) remains unclear. This study aimed to investigate the effect of PH-ECG on door-to-device time in patients with CS-STEMI. METHODS: This study enrolled CS-STEMI (Killip class IV) patients who were transferred directly to hospitals by ambulance (n = 517) from the Kanagawa Acute Cardiovascular Registry database. Patients were divided into PH-ECG (+) (n = 270) and PH-ECG (-) (n = 247) groups. Patients who experienced out-of-hospital cardiac arrest, who did not undergo emergent coronary intervention, or whose data were missing were excluded. Patient characteristics, FMC-to-door time, door-to-device time, and in-hospital mortality were compared between the groups. RESULTS: The patient backgrounds of the PH-ECG (+) and PH-ECG (-) groups were comparable. The peak creatinine kinase level was greater in the PH-ECG (+) group than in the PH-ECG (-) group [2756 (1292-6009) IU/ml vs. 2270 (957-5258) IU/ml, p = 0.048]. The FMC-to-door time was similar between the two groups [25 (20-33) min vs. 27 (20-35) min, p = 0.530], while the door-to-device time was significantly shorter in the PH-ECG group [74 (52-103) min vs. 83 (62-111) min, p = 0.007]. In-hospital mortality did not differ between the two groups (18 % vs. 21 %, p = 0.405). Multivariable logistic regression analyses revealed that PH-ECG (+) was independently associated with a door-to-device time < 60 min [odds ratio (95 % confidence intervals): 1.88 (1.24-2.83), p = 0.003]. CONCLUSIONS: PH-ECG was significantly associated with shorter door-to-device times in patients with CS-STEMI. Further studies with larger populations and more defined protocols are required to evaluate the utility of PH-ECG in patients with CS-STEMI.

Prevalence of cardiac amyloidosis in atrial fibrillation: a CMR study prior to catheter ablation.

The frequency of cardiac amyloidosis potentially present in patients with atrial fibrillation (AF) remains unclear. The purpose of this study is to determine the frequency and clinical characteristics of cardiac amyloidosis latent in AF by performing cardiac magnetic resonance imaging (MRI) in patients scheduled for AF ablation. We retrospectively analyzed 193 consecutive patients who underwent CA and cardiac MRI for atrial fibrillation. The primary endpoint of the study was the frequency of histologically confirmed cardiac amyloidosis or suspected cardiac amyloidosis [positive imaging findings on cardiac MRI strongly suspecting cardiac amyloidosis (diffuse subendocardial late gadolinium enhancement or MRI-derived extracellular volume of > 0.40)]. Among the 193 patients, 8 were confirmed or suspected cases of cardiac amyloidosis, representing a frequency of 4% (8/193 patients). Multivariate analysis identified interventricular septal thickness at end-diastole (LVSd) as an independent and significant predictor of cardiac amyloidosis (OR: 1.72, 95% CI 1.12-2.87, p = 0.020).The optimal cut-off value for IVSd was determined to be > 12.9 mm based on the Youden index. At this cut-off, the sensitivity was 75.0% (95% CI 34.9-96.8%) and the specificity was 92.3% (95% CI 87.4-95.7%), allowing for the identification of patients with definite or suspected cardiac amyloidosis. The frequency of confirmed and suspected cases of cardiac amyloidosis among patients with an IVSd > 12.9 mm was 30% (6/20 patients). In addition, prevalence of biopsy-proven cardiac amyloidosis was 10% (2/20). The prevalence of cardiac amyloidosis in atrial fibrillation patients scheduled for ablation with cardiac hypertrophy is not negligible.

Head impact differences in blind football between Rio 2016 and Tokyo 2020 Paralympic Games: video-based observational study.

OBJECTIVE: In Tokyo 2020 Paralympic Games, there were the rule and goal size changes at the blind football competition. This study aimed to compare the scoring and head impact characteristics during blind football competition between the Rio 2016 and Tokyo 2020 Paralympic Games using the official videos. DESIGN: Video-based observational study. PARTICIPANTS: In total, 36 blind football (men's football 5-a-side) game videos were obtained from the official International Paralympic Committee. PRIMARY AND SECONDARY OUTCOME MEASURES: Head impact was defined as the sudden contact of any object with the head. Videos were analysed to assess the number of scores and head impacts along with their corresponding details (ie, round, playing phase, scoring situation, impact situation, occurrence area, impact object, head impact site, fall and foul). RESULTS: The total number of goals scored at the Tokyo 2020 Paralympic Games was nearly double that at the Rio 2016 Paralympic Games. Regarding head impacts, a total of 2036 cases (Rio 2016, n=1105; Tokyo 2020, n=931) were evaluated. Significant differences were observed in head impact characteristics between the Rio 2016 and Tokyo 2020 Paralympic Games among seven outcomes (round, scoring situation, impact situation, occurrence area, impact object, site of head impact and fall). CONCLUSIONS: Compared with the Rio 2016 Paralympic Games, the Tokyo 2020 Paralympic Games showed an increase in the number of points scored and different head impact characteristics.

Evaluation of four computed tomography reconstruction algorithms using a coronary artery phantom.

Background: Despite advancements in coronary computed tomography angiography (CTA), challenges in positive predictive value and specificity remain due to limited spatial resolution. The purpose of this experimental study was to investigate the effect of 2nd generation deep learning-based reconstruction (DLR) on the quantitative and qualitative image quality in coronary CTA. Methods: A vessel model with stepwise non-calcified plaque was scanned using 320-detector CT. Image reconstruction was performed using four techniques: hybrid iterative reconstruction (HIR), model-based iterative reconstruction (MBIR), DLR, and 2nd generation DLR. The luminal peak CT number, contrast-to-noise ratio (CNR), and edge rise slope (ERS) were quantitatively evaluated via profile curve analysis. Two observers qualitatively graded the graininess, lumen sharpness, and overall lumen visibility on the basis of the degree of confidence for the stenosis severity using a five-point scale. Results: The image noise with HIR, MBIR, DLR, and 2nd generation DLR was 23.0, 21.0, 16.9, and 9.5 HU, respectively. The corresponding CNR (25% stenosis) was 15.5, 15.9, 22.1, and 38.3, respectively. The corresponding ERS (25% stenosis) was 203.2, 198.6, 228.9, and 262.4 HU/mm, respectively. Among the four reconstruction methods, the 2nd generation DLR achieved the significantly highest CNR and ERS values. The score of 2nd generation DLR in all evaluation points (graininess, sharpness, and overall lumen visibility) was higher than those of the other methods (overall vessel visibility score, 2.6±0.5, 3.8±0.6, 3.7±0.5, and 4.6±0.5 with HIR, MBIR, DLR, and 2nd generation DLR, respectively). Conclusions: 2nd generation DLR provided better CNR and ERS in coronary CTA than HIR, MBIR, and previous-generation DLR, leading to the highest subjective image quality in the assessment of vessel stenosis.

Relationship between 2nd-generation angiotensin receptor blockers and the risk of hypotension in COVID-19 patients admitted to hospital.

It has not yet been established whether angiotensin II receptor blockers (ARB), statins, and multiple drugs affect the severity of COVID-19. Therefore, we herein performed an observational study on the effects of 1st- and 2nd-generation ARB, statins, and multiple drugs, on COVID-19 in patients admitted to 15 Japanese medical facilities. The results obtained showed that ARB, statins, and multiple drugs were not associated with the primary outcome (odds ratio: 1.040, 95% confidence interval: 0.688-0.571; 0.696, 0.439-1.103; 1.056, 0.941-1.185, respectively), each component of the primary outcome (in-hospital death, ventilator support, extracorporeal membrane oxygenation support, and admission to the intensive care unit), or the secondary outcomes (oxygen administration, disturbed consciousness, and hypotension, defined as systolic blood pressure ≤90 mmHg). ARB were divided into 1st- and 2nd-generations based on their approval for use (before 2000 and after 2001), with the former consisting of losartan, candesartan, and valsartan, and the latter of telmisartan, olmesartan, irbesartan, and azilsartan. The difference of ARB generation was not associated with the primary outcome (odds ratio with 2nd-generation ARB relative to 1st-generation ARB: 1.257, 95% confidence interval: 0.613-2.574). The odd ratio for a hypotension as one of the secondary outcomes with 2nd-generation ARB was 1.754 (95% confidence interval: 1.745-1.763) relative to 1st-generation ARB. These results suggest that patients taking 2nd-generation ARB may be at a higher risk of hypotension than those taking 1st-generation ARB and also that careful observations are needed. Further studies are continuously needed to support decisions to adjust medications for co-morbidities.

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.

Microvascular dysfunction in patients with heart failure with preserved ejection fraction: A meta-analysis.

BACKGROUND: Although microvascular dysfunction (MVD) is considered an essential pathophysiology in patients with heart failure with preserved ejection fraction (HFpEF), the frequency and prognostic impact of MVD are not fully understood. This meta-analysis evaluated the frequency of MVD in patients with HFpEF and its utility in risk stratification. MATERIALS AND METHODS: On May 26, 2022, a literature search was performed on PubMed, Web of Science, the Cochrane library, and Embase using the search terms such as "Heart failure with preserved ejection fraction," "HFpEF," "microvascular dysfunction," and "MVD." The prevalence of MVD in patients with HFpEF was calculated using the general inverse variance method. A comprehensive literature review was conducted to examine the association between MVD and prognosis in patients with HFpEF. RESULTS: Data pertaining to a total of 941 patients diagnosed with HFpEF were extracted from the collective pool of 9 studies. The results of the meta-analysis revealed that the frequency of MVD among patients with HFpEF was found to be 55.5% (95% CI: 34.8%-76.2%), with a substantial degree of heterogeneity (I2 = 98%, p for heterogeneity <.001). Among the five studies that provided data on the association between MVD and prognosis, a significant statistical association was observed in four of them. CONCLUSIONS: This meta-analysis revealed that approximately 50% of patients diagnosed with HFpEF exhibited MVD. Moreover, the presence of MVD demonstrated significant prognostic implications in multiple studies conducted on patients with HFpEF. These findings strongly suggest that MVD plays a crucial role in the underlying pathophysiology of patients with HFpEF.

Diagnostic accuracy of whole heart coronary magnetic resonance angiography: a systematic review and meta-analysis.

BACKGROUND: The purpose of this meta-analysis was to comprehensively investigate the diagnostic ability of 1.5 T and 3.0 T whole heart coronary angiography (WHCA) to detect significant coronary artery disease (CAD) on X-ray coronary angiography. METHODS: A literature search of electronic databases, including PubMed, Web of Science Core Collection, Cochrane advanced search, and EMBASE, was performed to retrieve and integrate articles showing significant CAD detectability of 1.5 and 3.0 T WHCA. RESULTS: Data from 1899 patients from 34 studies were included in the meta-analysis. 1.5 T WHCA had a summary area under ROC of 0.88 in the patient-based analysis, 0.90 in the vessel-based analysis, and 0.92 in the segment-based analysis. These values for 3.0 T WHCA were 0.94, 0.95, 0.96, respectively. Contrast-enhanced 3.0 T WHCA had significantly higher specificity than non-contrast-enhanced 1.5 T WHCA on a patient-based analysis (0.87, 95% CI 0.80-0.92 vs. 0.74, 95% CI 0.64-0.82, P = 0.02). There were no differences in diagnostic performance on a patient-based analysis by use of vasodilators, beta-blockers or between Asian and Western countries. CONCLUSIONS: The diagnostic performance of WHCA was deemed satisfactory, with contrast-enhanced 3.0 T WHCA exhibiting higher specificity compared to non-contrast-enhanced 1.5 T WHCA in a patient-based analysis. There were no significant differences in diagnostic performance on a patient-based analysis in terms of vasodilator or beta-blocker use, nor between Asian and Western countries. However, further large-scale multicentre studies are crucial for the widespread global adoption of WHCA.

Severe multivessel coronary vasospasm in a patient with coronavirus disease 2019.

We present the case of a 65-year-old male with multivessel coronary spasm presumably related to coronavirus disease 2019 (COVID-19). Acetylcholine coronary angiogram and cardiac magnetic resonance imaging were used for the diagnosis. As the precise pathophysiology of myocardial injury by COVID-19 remains unclear, the multimodality approach may contribute to the accurate diagnosis. Learning objective: Myocardial involvement by severe acute respiratory syndrome coronavirus 2 infection is related to various pathologies. It is important to evaluate the degrees of cardiac damage and make a diagnosis by multimodality imaging especially with cardiac magnetic resonance.

Head Impact in Blind Football During the Tokyo Paralympics: Video-Based Observational Study.

ABSTRACT: Head impacts during blind football are common and have high injury rates; however, their characteristics and impact are still underreported. We compared head impact characteristics in blind football players with and without falls on all 18 official blind football match videos from the Tokyo 2020 Paralympic games. The rate of head impacts with falls was significantly higher in the preliminary phase, offense phase, and during dribbling. Significant differences in the region of the head impacted were also observed among the impact subjects/objects. The findings in this study would contribute to the development of injury prevention measures to minimize head injuries from head impact in blind football.

Characteristics of Wheelchair Basketball Falls During the Tokyo 2020 Paralympics by Sex and Physical Impairment Classification: A Video-Based Observational Study.

OBJECTIVE: The aim of the study is to evaluate the fall characteristics of wheelchair basketball players by sex and impairment classification using the official videos of the Tokyo 2020 Summer Paralympic Games. DESIGN: This was a video-based observational study. In total, 42 men's and 31 women's wheelchair basketball game videos were obtained from the official International Paralympic Committee. The videos were analyzed to assess the number of falls, playing time of the fall, playing phase, contact, foul judgment, fall location/direction, and the body part that first impacted the floor. RESULTS: A total of 1269 falls (men, n = 944; and women, n = 325) occurred. The analysis of men demonstrated significant differences in rounds, playing phase, location of fall, and body part first impacted. Women demonstrated significant differences in all categories except in rounds. Comparisons by functional impairment showed different trends for men and women. CONCLUSIONS: The detailed observation of videos suggested that men are more likely to have dangerous falls. There is a necessity for discuss the prevention measures based on sex and impairment classification.

Contrast defect of left atrial appendage on computed tomography is associated with higher risk of recurrence after catheter ablation in patients with paroxysmal atrial fibrillation.

The previous study has shown that the contrast defect of the left atrial appendage (LAA) on contrast-enhanced cardiac computed tomography (CT) is associated with a higher rate of stroke in patients with atrial fibrillation (AF). This study aimed to investigate the association between LAA CT contrast defect and the risk of arrhythmia recurrence after catheter ablation (CA) in patients with paroxysmal AF. A total of 283 paroxysmal AF patients [age: 67 ± 10 years, 185 (65%) males] who underwent cardiac CT before CA were retrospectively analyzed. The presence or absence of LAA CT contrast defect was visually assessed using early phase CT images. Recurrence was an episode of atrial arrhythmia beyond the first 90 days post-ablation. LAA flow velocity was measured using transesophageal echocardiography in 246 paroxysmal AF patients. Sixty-eight (24%) patients had an LAA CT contrast defect. LAA flow velocity was significantly reduced in patients with LAA CT defect compared to those without (56.8 ± 28.7 cm/s vs. 41.1 ± 19.1 cm/s, p < 0.001). During a median follow-up period of 858 days, arrhythmia recurrence was identified in 85 (30%) patients. On a Kaplan Meier curve, patients with LAA CT contrast defect had significantly higher recurrence rates than those without (p = 0.043). On a multivariable Cox regression analysis, LAA CT contrast defect was a significant and independent predictor after adjustment of age, sex and left atrial volume index (hazard ratio: 1.79, 95% confidence interval: 1.03-3.07, p = 0.036). LAA CT contrast defect was associated with decreased LAA flow velocity and a higher rate of arrhythmia recurrence after CA, suggesting its usefulness as a non-invasive predictor for high-risk AF patients resistant to CA therapy.

Machine learning to predict left ventricular reverse remodeling by guideline-directed medical therapy by utilizing texture feature of extracellular volume fraction in patients with non-ischemic dilated cardiomyopathy.

Extracellular volume fraction (ECV) by cardiac magnetic resonance (CMR) allows for the non-invasive quantification of diffuse myocardial fibrosis. Texture analysis and machine learning are now gathering attention in the medical field to exploit the ability of diagnostic imaging for various diseases. This study aimed to investigate the predictive value of texture analysis of ECV and machine learning for predicting response to guideline-directed medical therapy (GDMT) for patients with non-ischemic dilated cardiomyopathy (NIDCM). A total of one-hundred and fourteen NIDCM patients [age: 63 ± 12 years, 91 (81%) males] were retrospectively analyzed. We performed texture analysis of ECV mapping of LV myocardium using dedicated software. We calculated nine histogram-based features (mean, standard deviation, maximum, minimum, etc.) and five gray-level co-occurrence matrices. Five machine learning techniques and the fivefold cross-validation method were used to develop prediction models for LVRR by GDMT based on 14 texture parameters on ECV mapping. We defined the LVRR as follows: LVEF increased ≥ 10% points and decreased LVEDV ≥ 10% on echocardiography after GDMT > 12 months. Fifty (44%) patients were classified as non-responders. The area under the receiver operating characteristics curve for predicting non-responder was 0.82 for eXtreme Gradient Boosting, 0.85 for support vector machine, 0.76 for multi-layer perception, 0.81 for Naïve Bayes, 0.77 for logistic regression, respectively. Mean ECV value was the most critical factor among texture features for differentiating NIDCM patients with LVRR and those without (0.28 ± 0.03 vs. 0.36 ± 0.06, p < 0.001). Machine learning analysis using the support vector machine may be helpful in detecting high-risk NIDCM patients resistant to GDMT. Mean ECV is the most crucial feature among texture features.

Radial versus femoral access in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction: A propensity-matched analysis from real-world data of the K-ACTIVE registry.

BACKGROUND: The access site for primary percutaneous coronary intervention (PCI) for patients with ST-elevation myocardial infarction (STEMI) recently shifted from femoral to radial. However, few real-world data on Japanese patients exist. METHODS: To elucidate the clinical selection and impact of the access site in STEMI patients, we analyzed a Japanese observational prospective multicenter registry of acute myocardial infarction (K-ACTIVE: Kanagawa ACuTe cardIoVascular rEgistry) in 2015 to 2021. Data were analyzed in the entire population and a propensity score-matched population adjusted for confounding factors. Major adverse cardiac event (MACE) was defined as cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke. Bleeding Academic Research Consortium (BARC) type 3 or 5 was used to assess bleeding events. MACE plus BARC type 3 or 5 bleeding were considered composite events. Clinical outcomes were followed for 30 days. RESULTS: The 6802 STEMI patients included 4786 patients with radial access (70.3 %) and 2016 with femoral access (29.7 %). Femoral access tended to be selected for more severe conditions than radial access. The median door-to-device time in the radial access group was significantly shorter than the femoral access group in the entire population (75 min versus 79 min, p < 0.01). After propensity score matching (each group, n = 1208), the incidence of MACE tended to be lower in the radial access group [risk ratio (RR) 0.83, 95 % confidence interval (CI) 0.63-1.09, p = 0.17]. The incidence of BARC 3 or 5 bleeding was significantly less in the radial access group (RR 0.47, 95%CI 0.23-0.97, p = 0.04). The incidence of composite events was significantly less in the radial access group (RR 0.74, 95%CI 0.57-0.96, p = 0.02). CONCLUSION: In STEMI patients undergoing primary PCI, in comparison to femoral access, radial access reduced composite events in the entire population and the matched population, through a reduction in MACE and BARC 3 or 5 bleeding.

Characteristics of Falls Among Men's Wheelchair Rugby Players in the Rio 2016 and Tokyo 2020 Summer Paralympic Games: A Video Analysis.

Wheelchair rugby is a contact sport in which falls are common and injury rates are high, yet the characteristics of the falls are still under-reported. We investigated the fall characteristics of men's wheelchair rugby players by functional classification, using all 36 official match videos from the Rio 2016 and Tokyo 2020 summer Paralympic Games. The videos were analyzed to evaluate the number of falls, playing time when the fall occurred, playing phase (offense or defense), contact with other players, foul judgement, direction of the fall, and the body part first in contact with the floor. All 182 men's wheelchair rugby players (Rio 2016, 94; Tokyo 2020, 88) were classified as low-point players or high-point players depending on their functional classification. A total of 200 falls were detected, 27 (13.5%) for low-point players and 173 (86.5%) for high-point players. Significant differences were noted between low-point players and high-point players in the direction of the fall and body part first in contact with the floor. High-point players had more falls in the forward and left-right directions, whereas low-point players were characterized by a higher percentage of falls in the left-right and backward directions. Additionally, high-point players landed on the floor with their hands with high frequency, whereas low-point players landed with their elbows and shoulders more often. Our findings suggest the significance of devising measures to prevent falls during men's wheelchair rugby games according to their functional classification.

Clinical impact of cardiac magnetic resonance in patients with suspected coronary artery disease associated with chronic kidney disease (AQUAMARINE-CKD study): study protocol for a randomized controlled trial.

BACKGROUND: Although screening for coronary artery disease (CAD) using computed tomography coronary angiography in patients with stable chest pain has been reported to be beneficial, patients with chronic kidney disease (CKD) might have limited benefit due to complications of contrast agent nephropathy and decreased diagnostic accuracy as a result of coronary artery calcifications. Cardiac magnetic resonance (CMR) has emerged as a novel imaging modality for detecting coronary stenosis and high-risk coronary plaques without contrast media that is not affected by coronary artery calcification. However, the clinical use of this technology has not been robustly evaluated. METHODS: AQUAMARINE-CKD is an open parallel-group prospective multicenter randomized controlled trial of 524 patients with CKD at high risk for CAD estimated based on risk factor categories for a Japanese urban population (Suita score) recruited from 6 institutions. Participants will be randomized 1:1 to receive a CMR examination that includes non-contrast T1-weighted imaging and coronary magnetic angiography (CMR group) or standard examinations that include stress myocardial scintigraphy (control group). Randomization will be conducted using a web-based system. The primary outcome is a composite of cardiovascular events at 1 year after study examinations: all-cause death, death from CAD, nonfatal myocardial infarction, nonfatal ischemic stroke, and ischemia-driven unplanned coronary intervention (percutaneous coronary intervention or coronary bypass surgery). DISCUSSION: If the combination of T1-weighted imaging and coronary magnetic angiography contributes to the risk assessment of CAD in patients with CKD, this study will have major clinical implications for the management of patients with CKD at high risk for CAD. TRIAL REGISTRATION: Japan Registry of Clinical Trials (jRCT) 1,052,210,075. Registered on September 10, 2021.

Analysis of wheelchair falls in team sports at the Paralympic Games: video-based descriptive comparison between the Rio 2016 and Tokyo 2020 games.

OBJECTIVES: To identify the fall characteristics of athletes in wheelchair rugby and wheelchair basketball during the Tokyo 2020 Paralympic Games and descriptively compare these with those of the Rio 2016 Paralympic Games. DESIGN: Cross-sectional analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: We obtained video footage from the International Paralympic Committee of the Tokyo 2020 Paralympic Games that included 8 teams from each of the 18 wheelchair rugby and 10 wheelchair basketball games (men and women). The data were analysed to evaluate the number of falls, class difference (low or high pointer), time of play during the fall, phase of play, contact with other athletes, fall direction, fall location and the body part that first contacted the floor during the fall. These data from the Rio 2016 and Tokyo 2020 games were compared. RESULTS: Overall, 430 falls (rugby, 104; men's basketball, 230 and women's basketball, 96) occurred (average per game ±SD: 5.8±3.1, 23.0±5.4 and 9.6±5.0, respectively). Significant differences in class, direction, fall location and body part point of contact between the three sports were observed. In wheelchair rugby, falls occurred mainly in high pointers and tended to be more lateral due to contact. In wheelchair basketball, falls occurred more in female high-pointers and in male low pointers, with more forward falls due to forward contact. Unlike in the Rio 2016 games, no difference between the events based on the presence or absence of contact was observed in the Tokyo 2020 games. CONCLUSIONS: The number of falls increased in Tokyo 2020 compared with Rio 2016, with no significant difference in the characteristics of falls between the Rio 2016 and Tokyo 2020 games. Only in men's wheelchair basketball, the number of falls in low pointers significantly increased in the Tokyo 2020 games when compared with that in the Rio 2016 games.

Effect of thoracic expansion restriction on scapulothoracic and glenohumeral joint motion during shoulder external rotation.

BACKGROUND: Shoulder external rotation in the throwing motion involves movement of the scapulothoracic and glenohumeral joints, thoracic spine, and the thorax. Restriction of thoracic expansion may decrease scapulothoracic joint motion and compensate by excessive glenohumeral joint motion. However, it is unclear how restricting the expansion of the thorax alters shoulder motion. OBJECTIVE: To elucidate changes in scapulothoracic and glenohumeral joint movements caused by restricted thoracic expansion. METHODS: Kinematic data were obtained using an electromagnetic tracking device (Liberty; Polhemus), from 18 male participants, during shoulder external rotation in the sitting position with and without restriction of thoracic expansion. The displacements from the start position to the maximum external rotation position were compared, and Pearson's correlation coefficient was calculated. RESULTS: A significant difference was observed in the scapulothoracic posterior tilt angle (P< 0.01) and glenohumeral external rotation angle (P< 0.01). A significant positive correlation existed between scapulothoracic posterior tilt and glenohumeral external rotation (P< 0.05) with and without restriction. CONCLUSIONS: Restriction of thoracic expansion decreased scapulothoracic motion and increased glenohumeral motion. Thus, a decrease in thoracic expansion may change scapulothoracic and glenohumeral movements, which may be a risk factor for throwing injuries.

Chronic kidney disease and clinical outcomes in patients with COVID-19 in Japan.

BACKGROUND: Identifying predictive factors for coronavirus disease 2019 (COVID-19) is crucial for risk stratification and intervention. Kidney dysfunction contributes to the severity of various infectious diseases. However, the association between on-admission kidney dysfunction and the clinical outcome in COVID-19 patients is unclear. METHODS: This study was a multicenter retrospective observational cohort study of COVID-19 patients, diagnosed by polymerase chain reaction. We retrospectively analyzed 500 COVID-19 patients (mean age: 51 ± 19 years) admitted to eight hospitals in Japan. Kidney dysfunction was defined as a reduced estimated glomerular filtration rate (< 60 mL/min/1.73 m2) or proteinuria (≥ 1 + dipstick proteinuria) on admission. The primary composite outcome included in-hospital death, extracorporeal membrane oxygenation, mechanical ventilation (invasive and noninvasive methods), and intensive care unit (ICU) admission. RESULTS: Overall, 171 (34.2%) patients presented with on-admission kidney dysfunction, and the primary composite outcome was observed in 60 (12.0%) patients. Patients with kidney dysfunction showed higher rates of in-hospital death (12.3 vs. 1.2%), mechanical ventilation (13.5 vs. 4.0%), and ICU admission (18.1 vs. 5.2%) than those without it. Categorical and multivariate regression analyses revealed that kidney dysfunction was substantially associated with the primary composite outcome. Thus, on-admission kidney dysfunction was common in COVID-19 patients. Furthermore, it correlated significantly and positively with COVID-19 severity and mortality. CONCLUSIONS: On-admission kidney dysfunction was associated with disease severity and poor short-term prognosis in patients with COVID-19. Thus, on-admission kidney dysfunction has the potential to stratify risks in COVID-19 patients.