Search

BackgroundThe present study examined the inhibitory action of temporary treatment with an angiotensin type 1 (AT1) receptor blocker (ARB) on vascular remodeling using hypertensive mice with overexpression of the human renin (hRN) and angiotensinogen (hANG) genes.MethodshRN/hANG transgenic mice (hRN/hANG-Tg) were treated with an ARB, valsartan, from 4 weeks of age. In some mice, valsartan treatment was stopped at 8 weeks of age (temporary treatment). Inflammatory vascular injury was induced by polyethylene-cuff placement around the femoral artery at the age of 10 weeks.ResultsCompared with wild-type (WT) mice, hRN/hANG-Tg showed higher blood pressure (BP) and enhancement of oxidative stress and medial thickening even before cuff placement. Inflammatory vascular remodeling and oxidative stress after cuff placement were further enhanced in hRN/hANG-Tg. Temporary treatment with valsartan continuously lowered BP even after cessation of administration, and inhibited these changes. In contrast, administration of hydralazine lowered BP to a similar level to that with valsartan, but did not inhibit medial thickening and inflammatory vascular remodeling. In contrast to the valsartan treatment, BP immediately increased to the untreated level after cessation of hydralazine.ConclusionsThese results indicate that temporary ARB treatment leads to prolonged effect of BP lowering and prevents vascular remodeling in hypertensive mice induced by activation of the human renin-angiotensin system. The inhibitory action of valsartan is not due to the BP lowering but is at least in part due to a decrease in oxidative stress and inflammation.American Journal of Hypertension (2011). doi:10.1038/ajh.2011.6 [ABSTRACT FROM AUTHOR]

BackgroundTo explore the metabolic actions of nifedipine on diabetes, we examined glucose intolerance and white adipose tissue changes in type 2 diabetic KK-Ay mice.MethodsMale KK-Ay mice were treated with nifedipine (1.5 mg/kg/day in lab chow) for 5 weeks, which did not affect blood pressure or feeding of KK-Ay mice.ResultsAfter treatment with nifedipine, body weight tended to decrease and the weight of white adipose tissue was reduced. Without food restriction, nifedipine decreased plasma insulin level, while plasma glucose level tended to decrease. In oral glucose tolerance test, nifedipine suppressed the increase in glucose level after a glucose load without affecting plasma insulin concentration. Nifedipine also improved the result of insulin tolerance test. In white adipose tissue, nifedipine increased adipocyte number and the expression of peroxisome proliferator-activated receptor-γ (PPARγ) and adipocyte fatty acid-binding protein related to adipocyte differentiation. In addition, expression of adiponectin, insulin receptor, insulin receptor substrate-1, and glucose transporter type-4 was also increased by nifedipine. Nifedipine also increased the expression of NO synthase in white adipose tissue. Nifedipine did not affect expression of angiotensin II type 1 (AT1) and type 2 (AT2) receptors in white adipose tissue. Such changes in white adipose tissue were apparent in retroperitoneal adipose tissue. Nifedipine did not change the expression of angiotensin receptors, renin receptor, and angiotensinogen in white adipose tissue. Moreover, nifedipine attenuated nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity and increased superoxide dismutase (SOD) activity in white adipose tissue.ConclusionThese results suggest that nifedipine can enhance insulin sensitivity and reduce white adipose tissue, possibly related to stimulation of adipocyte differentiation.American Journal of Hypertension (2011). doi:10.1038/ajh.2010.198 [ABSTRACT FROM AUTHOR]

BackgroundPrevious reports indicated that blockade of AT1 receptor stimulation attenuated adipocyte dysfunction. However, the effects of AT2 receptor stimulation on adipose tissue were not yet clear. In the present study, we examined the adipose tissue dysfunction in atherosclerotic apolipoprotein E knockout (ApoEKO) mice with AT2 receptor deficiency.MethodsMale ApoEKO and AT2 receptor/ApoE knockout (AT2/ApoEKO) mice at 6 weeks of age were treated with a normal diet or a high-cholesterol diet (HCD: 1.25% cholesterol). Markers for adipocyte differentiation and inflammation in adipose tissue were assayed with real-time reverse-transcription-PCR and western blot.ResultsCompared with ApoEKO mice, AT2/ApoEKO mice with a normal diet showed only a decrease in expression of adiponectin and CCAAT/enhancer binding protein δ (C/EBPδ) in epididymal adipose tissue without changes in body weight, adipose tissue weight, and adipocyte number even at 6 months of age. After HCD for 4 weeks, the weight of both epididymal and retroperitoneal adipose tissue in AT2/ApoEKO mice was greater than that in ApoEKO mice without a change in body weight. Plasma concentrations of cholesterol and fatty acids were higher in AT2/ApoEKO mice than in ApoEKO mice. In adipose tissue of AT2/ApoEKO mice, the adipocyte number was decreased and the expression of peroxisome proliferator–activated receptor γ (PPARγ), C/EBPα, and aP2 was lower than that in ApoEKO mice, in association with an increase in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity.ConclusionsThese results suggest that AT2 receptor stimulation in adipose tissue is involved in the improvement of adipocyte differentiation and adipose tissue dysfunction in atherosclerotic model.American Journal of Hypertension 2009; doi:10.1038/ajh.2009.85American Journal of Hypertension 2009; 22, 7, 784–791. doi:10.1038/ajh.2009.85 [ABSTRACT FROM AUTHOR]

BackgroundA combination of different types of antihypertensive drugs is widely used for the treatment of hypertension. We examined the inhibitory effects of a combination of an AT1 receptor blocker (ARB), olmesartan, with various calcium channel blockers (CCBs) on inflammatory vascular remodeling.MethodsInflammatory vascular remodeling was induced by polyethylene-cuff placement around the femoral artery of C57BL/6J mice at 10 weeks of age. Olmesartan (0.5 mg/kg/day) was administered intraperitoneally using an osmotic minipump. CCBs (nifedipine 1.0 mg/kg/day, amlodipine 0.1 mg/kg/day, azelnidipine 0.1 mg/kg/day), and hydrochlorothiazide (HCTZ 0.5 mg/kg/day) were administered orally.ResultsIn the injured artery, superoxide anion production and expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits p47phox and Rac-1 were markedly increased, together with expression of monocyte chemotactic protein-1 (MCP-1) and tumor necrosis factor (TNF)-α. Administration of a single drug alone at each concentration did not significantly inhibit these changes in the injured artery. However, a combination of olmesartan with various CCBs inhibited neointimal formation as well as oxidative stress and inflammatory markers in the injured artery. Moreover, among these CCBs, inhibition of these markers by olmesartan with azelnidipine was stronger than that caused by a combination with other CCBs. On the other hand, a combination of subeffective doses of olmesartan and HCTZ did not significantly affect vascular changes after cuff placement.ConclusionsThese results suggest that the combination of ARB with CCB synergistically inhibits vascular remodeling and that the inhibitory actions of ARB on vascular remodeling may vary depending on the combined CCB.American Journal of Hypertension (2009). doi:10.1038/ajh.2008.344American Journal of Hypertension (2009); 22, 2, 145–150. doi:10.1038/ajh.2008.344 [ABSTRACT FROM AUTHOR]

BACKGROUND The roles of the angiotensin (Ang) II type 1 (AT1) receptor in the changes in white adipose tissue were explored in an animal model of atherosclerosis using apolipoprotein E-deficient (ApoEKO) mice. METHODS Apolipoprotein E-deficient (ApoEKO) mice and KK-Ay mice were used. Expression of markers for adipocyte differentiation and inflammation was determined by real-time reverse-transcription polymerase chain reaction. RESULTS Adipose tissue weight and adipocyte size in epididymal white adipose tissue were increased in ApoEKO mice and KK-Ay mice. In the adipose tissue of these models, expression of adiponectin and peroxisome proliferator-activated receptor-γ (PPARγ), which induce adipocyte differentiation, and expression of transcription factors of adipocyte differentiation, such as CCAAT-enhancer-binding protein-α (C/EBPα) and aP2, were decreased. Expression of inflammatory markers and nicotinamide adenine dinucleotide phosphate oxidase subunits was also increased. Deletion of AT1a receptor in ApoEKO mice and administration of an AT1 receptor blocker, valsartan, to KK-Ay mice reduced epididymal adipose tissue weight and adipocyte size significantly. Blockade of the AT1 receptor also reduced the expression of inflammatory chemokines and oxidative stress markers. Moreover, AT1a receptor deletion in ApoEKO mice and AT1 receptor blockade in KK-Ay mice prevented the decrease in expression of adiponectin, PPARγ, C/EBPα, and aP2. Valsartan also increased glucose uptake induced by insulin in adipose tissue of KK-Ay mice. CONCLUSIONS These results suggest that enlargement and weakened differentiation of adipocytes are observed in atherosclerosis and diabetes, and that AT1 receptor blockade prevented adipocyte enlargement and promoted adipocyte differentiation in these models. [ABSTRACT FROM AUTHOR]

Background: The effect of a calcium channel blocker (CCB) on the expression of monocyte chemoattractant protein (MCP)-1 was explored in inflammatory vascular injury, focusing on the role of nuclear factor (NF)-κB. Methods: Vascular injury was induced by cuff placement. Expression of MCP-1 was determined by real-time RT-PCR. NF-κB expression and its activity were detected by Western blot and electrophoretic mobility shift assay. Results: Polyethylene cuff placement around the mouse femoral artery increased MCP-1 expression, together with proliferation of vascular smooth muscle cells and neointimal formation in the injured artery. The content of NF-κB was decreased in the cytosolic fraction but increased in the nuclear fraction prepared from the injured artery. In the nuclear fraction, the binding activity of NF-κB to the promoter region of MCP-1 was markedly increased. On the other hand, IκB content in the cytosolic fraction was decreased in the injured artery after cuff placement, accompanied by an increase in IκB kinase (IKK) phosphorylation. Treatment of mice with a CCB, nifedipine, at a dose of 5 mg/kg/day, significantly decreased vascular smooth muscle cell proliferation and neointimal formation without affecting blood pressure. This dose of nifedipine inhibited the increase in MCP-1 expression in the injured artery. Moreover, nifedipine reduced the nuclear content and DNA-binding activity of NF-κB in the injured artery. In contrast, the decrease in IκB content and the increase in IKK phosphorylation in the cytosolic fraction were attenuated by nifedipine. Conclusions: These results indicate that MCP-1 expression in inflammatory vascular injury is regulated by activation of NF-κB. The results also suggest that nifedipine attenuates MCP-1 expression in the injured artery via inhibition of the nuclear translocation and DNA-binding activity of NF-κB, and thereby improves vascular remodeling. [Copyright &y& Elsevier]

We evaluated the feasibility of myocardial perfusion ratio to the aorta (MPR) in static computed tomography perfusion (CTP) for detecting myocardial perfusion abnormalities assessed by single-photon emission computed tomography (SPECT). Twenty-five patients with suspected coronary artery disease who underwent dynamic CTP and SPECT were retrospectively evaluated. CTP images scanned at a sub-optimal phase for detecting myocardial perfusion abnormalities were selected from dynamic CTP images and used as static CTP images in the present study. The diagnostic accuracy of MPR derived from static CTP was compared to those of visual assessment and conventional quantitative parameters such as myocardial CT attenuation (HU) and transmural perfusion ratio (TPR). The area under the curve of MPR (0.84; 95% confidence interval [CI], 0.76–0.90) was significantly higher than those of myocardial CT attenuation (0.73; 95% CI, 0.65–0.79) and TPR (0.76; 95% CI, 0.67–0.83) (p < 0.05). Sensitivity and specificity were 67% (95% CI, 54–77%) and 90% (95% CI, 86–92%) for visual assessment, 51% (95% CI, 39–63%) and 86% (95% CI, 82–89%) for myocardial CT attenuation, 63% (95% CI, 51–74%) and 84% (95% CI, 80–88%) for TPR, and 78% (95% CI, 66–86%) and 84% (95% CI, 80–88%) for MPR, respectively. MPR showed higher diagnostic accuracy for detecting myocardial perfusion abnormality compared with myocardial CT attenuation and TPR. [ABSTRACT FROM AUTHOR]

Objectives: This study evaluated the feasibility of a model-based iterative reconstruction technique (MBIR) tuned for the myocardium on myocardial computed tomography late enhancement (CT-LE)., Methods: Twenty-eight patients who underwent myocardial CT-LE and late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) within 1 year were retrospectively enrolled. Myocardial CT-LE was performed using a 320-row CT with low tube voltage (80 kVp). Myocardial CT-LE images were scanned 7 min after CT angiography (CTA) without additional contrast medium. All myocardial CT-LE images were reconstructed with hybrid iterative reconstruction (HIR), conventional MBIR (MBIR&#95;cardiac), and new MBIR tuned for the myocardium (MBIR&#95;myo). Qualitative (5-grade scale) scores and quantitative parameters (signal-to-noise ratio [SNR] and contrast-to-noise ratio [CNR]) were assessed as image quality. The sensitivity, specificity, and accuracy of myocardial CT-LE were evaluated at the segment level using an American Heart Association (AHA) 16-segment model, with LGE-MRI as a reference standard. These results were compared among the different CT image reconstructions., Results: In 28 patients with 448 segments, 160 segments were diagnosed with positive by LGE-MRI. In the qualitative assessment of myocardial CT-LE, the mean image quality scores were 2.9 ± 1.2 for HIR, 3.0 ± 1.1 for MBIR&#95;cardiac, and 4.0 ± 1.0 for MBIR&#95;myo. MBIR&#95;myo showed a significantly higher score than HIR (P < 0.001) and MBIR&#95;cardiac (P = 0.018). In the quantitative image quality assessment of myocardial CT-LE, the median image SNR was 10.3 (9.1-11.1) for HIR, 10.8 (9.8-12.1) for MBIR&#95;cardiac, and 16.8 (15.7-18.4) for MBIR&#95;myo. The median image CNR was 3.7 (3.0-4.6) for HIR, 3.8 (3.2-5.1) for MBIR&#95;cardiac, and 6.4 (5.0-7.7) for MBIR&#95;myo. MBIR&#95;myo significantly improved the SNR and CNR of CT-LE compared to HIR and MBIR&#95;cardiac (P < 0.001). The sensitivity, specificity, and accuracy for the detection of myocardial CT-LE were 70%, 92%, and 84% for HIR; 71%, 92%, and 85% for MBIR&#95;cardiac; and 84%, 92%, and 89% for MBIR&#95;myo, respectively. MBIR&#95;myo showed significantly higher image quality, sensitivity, and accuracy than the others (P < 0.05)., Conclusions: MBIR tuned for myocardium improved image quality and diagnostic performance for myocardial CT-LE assessment., Competing Interests: Conflict of interest: Shota Nakano is an employee of Canon Medical Systems Corporation. The rest of the authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) stabilizes hemodynamics in an electrical storm leading to cardiogenic shock. However, adverse effects of VA-ECMO are increased left ventricular (LV) afterload and LV end-diastolic pressure due to retrograde blood return. These adverse effects could be ameliorated by LV unloading with Impella insertion. This case illustrates the possible efficacy of adjunctive Impella insertion for a refractory electrical storm that is resistant to defibrillation under mechanical support with VA-ECMO for cardiogenic shock., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Akazawa et al.)

Competing Interests: Disclosures None.

Aims: As part of the Toon Health Study, which is an ongoing population-based cohort study, we aimed to develop a prediction model for N-terminal pro-brain natriuretic peptide (NT-proBNP) in a general Japanese population. We sought to explore the influence of various demographic and clinical factors on NT-proBNP levels and assess the model's performance. In addition, our objectives included internal validation and investigation of the diagnostic potential of the observed-to-predicted NT-proBNP ratio (OPR) at baseline for predicting the risk of heart failure with preserved ejection fraction (HFpEF)., Methods and Results: In this prospective cohort study, participants were recruited from Toon City, Japan, as part of the larger Toon Health Study, focusing on cardiovascular risk factors. We measured the NT-proBNP levels and used linear regression with penalization (ridge regression) to develop the model. The model incorporated 10 prespecified predictors (age, gender, body mass index, diastolic blood pressure, heart rate, haemoglobin, albumin, total cholesterol, haemoglobin A1c, and estimated glomerular filtration rate) and underwent assessment using R 2 and root mean squared error (RMSE). Internal validation was conducted through bootstrapping. In a post hoc analysis, we explored the OPR's diagnostic potential using 5 year follow-up data (n = 636) to predict the elevation of NT-proBNP > 125 pg/mL at the 5 year follow-up as the risk of HFpEF. A total of 2505 participants (age: 60.4 ± 12.9 years, men: 35%) were enrolled in this study. There was a linear relationship between the observed and predicted values of NT-proBNP in which the logarithm of observed NT-proBNP was <6, which corresponds to 403 pg/mL in NT-proBNP. The prediction model demonstrated satisfactory performance (R 2 : 0.291, RMSE: 0.688), with age identified as a dominant predictor. The stability of the model was underscored by the internal validation. The OPR at baseline predicted NT-proBNP > 125 pg/mL at the 5 year follow-up with an area under the curve of 0.793., Conclusions: This study introduces the first prediction model for NT-proBNP in a general Japanese population. Although the model has acceptable performance, ongoing refinement is essential. Our transparent approach to model development, alongside a web-based interactive tool, lays the groundwork for further improvements and external validation. The OPR holds potential for predicting the future risk of HFpEF. This research contributes to understanding the nuanced influence of patient backgrounds on levels of NT-proBNP in asymptomatic individuals within the context of a broader population-based cohort study., (© 2024 The Authors. ESC Heart Failure published by John Wiley & Sons Ltd on behalf of European Society of Cardiology.)

Objectives: This study aimed to investigate the utility of the RAND/UCLA appropriateness method (RAM) in validating expert consensus-based multiple-choice questions (MCQs) on electrocardiogram (ECG)., Methods: According to the RAM user's manual, nine panelists comprising various experts who routinely handle ECGs were asked to reach a consensus in three phases: a preparatory phase (round 0), an online test phase (round 1), and a face-to-face expert panel meeting (round 2). In round 0, the objectives and future timeline of the study were elucidated to the nine expert panelists with a summary of relevant literature. In round 1, 100 ECG questions prepared by two skilled cardiologists were answered, and the success rate was calculated by dividing the number of correct answers by 9. Furthermore, the questions were stratified into "Appropriate," "Discussion," or "Inappropriate" according to the median score and interquartile range (IQR) of appropriateness rating by nine panelists. In round 2, the validity of the 100 ECG questions was discussed in an expert panel meeting according to the results of round 1 and finally reassessed as "Appropriate," "Candidate," "Revision," and "Defer.", Results: In round 1 results, the average success rate of the nine experts was 0.89. Using the median score and IQR, 54 questions were classified as " Discussion." In the expert panel meeting in round 2, 23% of the original 100 questions was ultimately deemed inappropriate, although they had been prepared by two skilled cardiologists. Most of the 46 questions categorized as "Appropriate" using the median score and IQR in round 1 were considered "Appropriate" even after round 2 (44/46, 95.7%)., Conclusions: The use of the median score and IQR allowed for a more objective determination of question validity. The RAM may help select appropriate questions, contributing to the preparation of higher-quality tests., (© 2024. The Author(s).)

An 89-year-old woman with a giant hiatal hernia complained of persistent chest pain. An electrocardiogram (ECG) showed hyperacute T waves, suggesting the early phase of ST-elevation myocardial infarction. After endoscopic drainage for hiatal hernia, the chest pain disappeared, and the ECG abnormalities resolved. The present case illustrates that compression of the heart by a giant hiatal hernia can induce T wave elevation mimicking acute coronary syndrome.

Competing Interests: Disclosures None.

Introduction: Although the ECG is an important diagnostic tool in medical practice, the competency of ECG interpretation is considered to be poor. Diagnostic inaccuracy involving the misinterpretation of ECG can lead to inappropriate medical judgements and cause negative clinical outcomes, unnecessary medical testing and even fatalities. Despite the importance of assessing ECG interpretation skills, there is currently no established universal, standardised assessment tool for ECG interpretation. The current study seeks to (1) develop a set of items (ECG questions) for estimating competency of ECG interpretation by medical personnel by consensus among expert panels following a process based on the RAND/UCLA Appropriateness Method (RAM) and (2) analyse item parameters and multidimensional latent factors of the test set to develop an assessment tool., Methods and Analysis: This study will be conducted in two steps: (1) selection of question items for ECG interpretation assessment by expert panels via a consensus process following RAM and (2) cross-sectional, web-based testing using a set of ECG questions. A multidisciplinary panel of experts will evaluate the answers and appropriateness and select 50 questions as the next step. Based on data collected from a predicted sample size of 438 test participants recruited from physicians, nurses, medical and nursing students, and other healthcare professionals, we plan to statistically analyse item parameters and participant performance using multidimensional item response theory. Additionally, we will attempt to detect possible latent factors in the competency of ECG interpretation. A test set of question items for ECG interpretation will be proposed on the basis of the extracted parameters., Ethics and Dissemination: The protocol of this study was approved by the Institutional Review Board of Ehime University Graduate School of Medicine (IRB number: 2209008). We will obtain informed consent from all participants. The findings will be submitted for publication in peer-reviewed journals., Competing Interests: Competing interests: TAF reports personal fees from Boehringer-Ingelheim, DT Axis, Kyoto University Original, Shionogi and SONY, and a grant from Shionogi, outside the submitted work. In addition, TAF has patents 2020-548587 and 2022-082495 pending, and intellectual property for Kokoro-app licensed to Mitsubishi-Tanabe. KY and MW have patent 2022-193813 pending outside the submitted work. MS reports personal fees from SONY outside the submitted work. The Institute for Airway Disease received a system development fee from the Department of Cardiology, Pulmonology, Nephrology and Hypertension, Ehime University Graduate School of Medicine. All other authors have no conflict of interest., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Intravascular imaging (IVI), including intravascular ultrasound (IVUS) and optical coherence tomography (OCT), is clinically useful for assessing the luminal size, lesion length, and plaque characteristics, as well as for evaluating stent deployment; however, it is not designed to estimate myocardial ischemia accurately. Thus, several types of IVI-derived fractional flow reserve (FFR) (IVI-derived FFR) have been developed and reported. In general, the algorithms of virtual FFR are based on basic fluid dynamics equations (mainly Poiseuille and Borda-Carnot equations) and original microvascular models (fixed velocity or calculating coronary flow reserve). Although the models and assumptions used in the past reports were mostly based on the standard population (not independent patient data), the developed software calculated FFR with high accuracy (88% to 94%) with strong correlations between IVI-derived FFR and wire-based FFR (0.69 to 0.89). Given several other less invasive virtual FFR methods currently available for clinical use, IVI-derived FFR would be limited for the sole use of pre-percutaneous coronary intervention (PCI) physiological evaluation; however, it may play a unique role at PCI guidance and optimization, potentially allowing comprehensive and time/cost-saving assessment of both anatomical and physiological lesion properties using a single diagnostic device., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Introduction: Coronavirus disease 2019 (COVID-19) symptoms are not fully understood in non-hospitalized individuals in Japan, and COVID-19 differentiation by symptoms alone remained challenging. Therefore, this study aimed to examine COVID-19 prediction from symptoms using real-world data in an outpatient fever clinic., Methods: We compared the symptoms of COVID-19-positive and negative patients who visited the outpatient fever clinic at Imabari City Medical Association General Hospital and tested for COVID-19 from April 2021 to May 2022. This retrospective single-center study enrolled 2,693 consecutive patients., Results: COVID-19-positive patients had a higher frequency of close contact with COVID-19-infected patients compared with COVID-19-negative patients. Moreover, patients with COVID-19 had high-grade fever at the clinic compared with patients without COVID-19. Additionally, the most common symptom in patients with COVID-19 was sore throat (67.3%), followed by cough (62.0%), which was approximately twice as common in patients without COVID-19. COVID-19 was more frequently identified in patients having a fever (≥37.5℃) with a sore throat, a cough, or both. The positive COVID-19 rate reached approximately half (45%) when three symptoms were present., Conclusion: These results suggested that COVID-19 prediction by combinations of simple symptoms and close contact with COVID-19-infected patients might be useful and lead to recommendations for testing of COVID-19 in symptomatic individuals., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Inaba et al.)

The slow flow phenomenon is a critical complication during percutaneous coronary intervention (PCI) that leads to poor outcomes. We aimed to evaluate the mechanisms underlying the slow flow phenomenon using intravascular ultrasound (IVUS). We retrospectively analyzed IVUS data from 62 lesions in 58 consecutive patients who experienced the slow flow phenomenon during PCI. IVUS was performed immediately after the development of the slow flow phenomenon to assess its cause. No IVUS-based evidence of mechanical obstruction was categorized as distal embolization. Distal embolization was observed in 46 lesions (74%). The slow flow phenomenon occurred in all these lesions after stent implantation. In addition to distal embolization, three different mechanisms underlying the induction of the slow flow phenomenon due to mechanical obstructions (16 lesions, 26%) were detected on IVUS, namely, medial dissection/hematoma (6 lesions), intimal flap (6 lesions), and thrombus obstruction (4 lesions). Most mechanical obstructions (13 lesions, 81%) could not be identified by angiography alone. In 15/16 lesions (94%) with mechanical obstruction, deteriorated flow improved immediately after balloon dilatation or bail-out stent implantation, although intracoronary vasodilator administration could not reestablish coronary flow. The frequency of mechanical obstruction as the cause of the slow flow phenomenon was relatively high. Given the difficulty in angiographical differentiation, IVUS-guided management of slow flow may be a useful strategy., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)