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.

Differences between Acute Embolic and Atherosclerotic Middle Cerebral Artery Occlusion in Multiphase Arterial Spin-labeling Imaging.

Arterial spin-labeling magnetic resonance imaging (ASL-MRI) is widely used for evaluating collateral development in patients with acute ischemic stroke (AIS). This study aimed to characterize the findings of multiphase ASL-MRI between embolic and atherosclerotic large vessel occlusion (LVO) to aid in the differential diagnosis. Among 982 patients with AIS, 44 who were diagnosed with acute, symptomatic, and unilateral occlusion of the horizontal segment of the middle cerebral artery (MCA) were selected and categorized into embolic stroke (ES) and atherosclerosis (AT) groups. Using ASL-MRI (postlabeling delay [PLD] of 1.5, 2.0, and 2.5 s) at admission, the ipsilateral to contralateral ratio (ICR) of the signal intensity and its time-course increasing rate (from PLD 1.5 to 2.0 and 2.5, ΔICR) were measured and compared between the two groups. The mean ICR was significantly higher in the AT group than in the ES group (AT vs. ES: 0.49 vs. 0.27 for ICR1.5, 0.73 vs. 0.32 for ICR2.0, and 0.92 vs. 0.37 for ICR2.5). The ΔICR of PLD 1.5-2.0 (ΔICR2.0) and 2.5 (ΔICR2.5) were also significantly higher in the AT group than in the ES group (AT vs. ES: 50.9% vs. 26.3% for ΔICR2.0, and 92.6% vs. 42.9% for ΔICR2.5). Receiver operating characteristic curves showed moderate-to-strong discriminative abilities of each ASL-MRI parameter in predicting MCA occlusion etiology. In conclusion, multiphase ASL-MRI parameters may aid in differentiating intracranial LVO etiology during the acute phase. Thus, it is applicable to AIS management.

Alternative Bypass Technique Using Radial Artery Graft between V3 Segment of Vertebral Artery and Middle Cerebral Artery: Technical Note.

BACKGROUND: There are some cases where a radial artery (RA) graft is needed for a high-flow extracranial to intracranial (EC-IC) bypass as the external carotid artery (ECA) cannot be utilized as a donor artery. In this report, we describe two cases of extracranial vertebral artery (VA) to middle cerebral artery (MCA) high-flow bypass using an RA graft with an artificial vessel as an alternative bypass technique. METHODS: The patient was placed supine with a head rotation of 80 degrees. After frontotemporal craniotomy, another C: -shaped skin incision was made at the retroauricular region and the V3 portion of the VA was exposed at the suboccipital triangle. Prior to attempting the high-flow bypass, the superficial temporal artery (STA) was anastomosed to the M4 portion of the MCA as an insurance bypass. The RA graft was anastomosed to the V3 portion of the VA that traveled under the periosteum at the supra-auricular region through an artificial vessel. After RA-M2 anastomosis, an alternative EC-IC bypass, the V3-RA-M2 bypass, was achieved. RESULTS: Postoperative angiography demonstrated successful graft patency and no perioperative complications were observed in both cases. CONCLUSIONS: In the cases where a high-flow bypass is required, the V3 portion of the VA is a suitable alternative proximal anastomosis site when the ECA is not a candidate donor. Furthermore, an artificial vessel shows satisfactory protection against graft complications.

Possible Delayed Foreign Body Reactions against Titanium Clips and Coating Materials after Unruptured Cerebral Aneurysm Surgery.

Delayed foreign body reactions to either or both clipping and coating materials have been reported in several small series; however, studies in the titanium clip era are scarce. This study aims to survey the contemporary status of such reactions to titanium clips and coating materials. Among patients who received a total of 2327 unruptured cerebral aneurysmal surgeries, 12 developed delayed intraparenchymal reactions during outpatient magnetic resonance imaging (MRI) follow-up. A retrospective investigation was conducted. The patients' average age was 58.6 (45-73) years, and 11 were women. The aneurysms were located in the middle cerebral artery (n = 7), internal carotid artery (n = 4), or anterior communicating artery (AComA, n = 1). In 10 patients, additional coating with tiny cotton fragments was applied to the residual neck after clipping with titanium clips; however, only the clipping with titanium clips was performed in the remaining two. The median time from surgery to diagnosis was 4.5 (0.3-60) months. Seven (58.3%) patients were asymptomatic, and three developed neurological deficits. MRI findings were characterized by a solid- or rim-enhancing lobulated mass adjacent to the clip with surrounding parenchymal edema. In 11 patients, the lesions reduced in size or disappeared; however, in one patient, an AComA aneurysm was exacerbated, necessitating its removal along with optic nerve decompression. In conclusion, cotton material is a strongly suspected cause of delayed foreign body reactions, and although extremely rare, titanium clips alone may also induce such a reaction. The prognosis is relatively good with steroid therapy; however, caution is required when the aneurysm is close to the optic nerve, as in AComA aneurysms.

Tissue Acceleration as a Novel Metric for Surgical Performance During Carotid Endarterectomy.

BACKGROUND AND OBJECTIVES: Gentle tissue handling to avoid excessive motion of affected fragile vessels during surgical dissection is essential for both surgeon proficiency and patient safety during carotid endarterectomy (CEA). However, a void remains in the quantification of these aspects during surgery. The video-based measurement of tissue acceleration is presented as a novel metric for the objective assessment of surgical performance. This study aimed to evaluate whether such metrics correlate with both surgeons' skill proficiency and adverse events during CEA. METHODS: In a retrospective study including 117 patients who underwent CEA, acceleration of the carotid artery was measured during exposure through a video-based analysis. Tissue acceleration values and threshold violation error frequencies were analyzed and compared among the surgeon groups with different surgical experience (3 groups: novice , intermediate , and expert ). Multiple patient-related variables, surgeon groups, and video-based surgical performance parameters were compared between the patients with and without adverse events during CEA. RESULTS: Eleven patients (9.4%) experienced adverse events after CEA, and the rate of adverse events significantly correlated with the surgeon group. The mean maximum tissue acceleration and number of errors during surgical tasks significantly decreased from novice, to intermediate, to expert surgeons, and stepwise discriminant analysis showed that the combined use of surgical performance factors could accurately discriminate between surgeon groups. The multivariate logistic regression analysis revealed that the number of errors and vulnerable carotid plaques were associated with adverse events. CONCLUSION: Tissue acceleration profiles can be a novel metric for the objective assessment of surgical performance and the prediction of adverse events during surgery. Thus, this concept can be introduced into futuristic computer-aided surgeries for both surgical education and patient safety.

Association between sarcopenia and exercise capacity in patients with pulmonary hypertension without left heart disease.

BACKGROUND: Pulmonary hypertension (PH) has recently been described as a complex clinical syndrome affecting multiple organ systems, including the heart, lungs, and skeletal muscle, each of which plays an important role in exercise capacity. However, the relationship between exercise capacity and skeletal muscle abnormalities in patients with PH has not been fully elucidated. METHODS: We retrospectively analysed the exercise capacity and measures of skeletal muscle of 107 patients with PH without left heart disease (mean age 63 ± 15 years, 32.7% males, n = 30/6/66/5 in the clinical classification Group 1/3/4/5). RESULTS: Sarcopenia, low appendicular skeletal muscle mass index, low grip strength, and slow gait speed, determined by international criteria, were found in 15 (14.0%), 16 (15.0%), 62 (57.9%), and 41 (38.3%) patients, respectively. The mean 6-min walk distance of all patients was 436 ± 134 m and was independently associated with sarcopenia (standardised ß = -0.292, p < 0.001). All patients with sarcopenia showed reduced exercise capacity defined as 6-min walk distance < 440 m. Multivariable logistic regression analysis showed that each of the components of sarcopenia was associated with reduced exercise capacity (adjusted odds ratio and 95% confidence interval of appendicular skeletal muscle mass index: 0.39 [0.24-0.63] per 1 kg/m2, p = 0.006, grip strength: 0.83 [0.74-0.94] per 1 kg, p = 0.003, and gait speed: 0.31 [0.18-0.51] per 0.1 m/s, p < 0.001). CONCLUSIONS: Sarcopenia and its components are associated with reduced exercise capacity in patients with PH. A multifaceted evaluation may be important in the management of reduced exercise capacity in patients with PH.

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.

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.

Aneuploidy and sex concordance rate between cell-free DNA analysis from spent culture media of preimplantation embryo and DNA from whole embryo with respect to different morphological grading.

Purpose: The aneuploidy and sex concordance between cell-free DNA in spent culture media (SCM) and DNA from whole embryo with respect to different morphological grading were examined to evaluate the feasibility of non-invasive preimplantation genetic testing for aneuploidy (niPGT-A). Methods: A total of 46 pairs of embryos and corresponding SCM were divided into two groups based on the morphological grade. DNA was extracted from 22 and 24 pairs of low- and high-grade embryos, respectively, and respective SCM followed by chromosomal analysis using next-generation sequencing. Aneuploidy study and sex determination were conducted for both groups, and concordance rates were calculated. Results: For low-grade embryos, 63.6% (14/22) were determined as aneuploidy by whole embryo analysis, and concordance rates were 54.5% (12/22) using niPGT-A. On the contrary, for high-grade embryos 41.7% (10/24) were determined as aneuploidy by whole embryo analysis, and concordance rates were 62.5% (15/24) using niPGT-A. The concordance rates were not statistically different between the low-grade and high-grade embryo groups (p = 0.804). For sex determination, concordance rates between whole embryo and SCM were 81.8% (18/22) and 87.5% (21/24) in low- and high-grade groups, respectively. Conclusion: Aneuploidy and sex evaluation by niPGT-A may be feasible for both morphologically low- and high-grade embryos.

Impact of early intervention with alogliptin on coronary plaque regression and stabilization in patients with acute coronary syndromes.

BACKGROUND AND AIMS: Anti-atherosclerotic effects of early intervention with dipeptidyl peptidase-4 inhibitors remain poorly defined. METHODS: In a prospective, single-center, randomized trial, 66 patients with acute coronary syndrome (ACS) and mild dysglycemia (HbA1c 6.0 (5.7, 6.3)%, 58% of impaired glucose tolerance) were randomly assigned to receive alogliptin (n = 33) or placebo (n = 33) in addition to standard treatments. Serial intravascular ultrasound (IVUS) was performed at baseline and 10 months to evaluate changes in coronary percent plaque volumes (%PV) and plaque tissue components of non-culprit lesions (NCLs). RESULTS: Baseline clinical and IVUS characteristics, as well as decreases in HbA1c and lipid variables during 10 months, did not differ significantly between the 2 groups. In contrast, with respect to vascular responses, the alogliptin group showed significantly greater decreases in plaque volumes (-0.3 ± 0.6 vs. -0.04 ± 0.7 mm3/mm, p = 0.03) and %PV (-0.9 ± 2.8 vs. 1.2 ± 3.6%, p = 0.01), with a tendency toward smaller lumen loss (-0.1 ± 0.7 vs. -0.4 ± 0.8 mm3/mm, p = 0.07) compared with the placebo group. Significantly decreased percent necrotic volumes (%NV) (-1.9 ± 3.8 vs. 0.3 ± 3.7%, p = 0.03) and increased fibrotic volumes (2.5 ± 5.0 vs. -0.3 ± 5.3%, p = 0.05) were or tended to be seen in alogliptin versus placebo groups at 10 months. In multiple regression analysis, alogliptin use was a statistically significant determinant of changes in %PV (ß = -0.33, p = 0.004) and %NV (ß = -0.28, p = 0.03) at 10 months. CONCLUSIONS: Alogliptin treatment, independently of glycemic and lipid status, resulted in significant plaque regression and stabilization in NCLs in patients with ACS and mild dysglycemia, suggesting the potential utility of early intervention with incretin-based treatments for this patients' subset.

Prehospital Administration of Aspirin and Nitroglycerin for Patients With Suspected Acute Coronary Syndrome　- A Systematic Review.

Background: Recent guidelines for acute coronary syndrome (ACS) recommend prehospital administration of aspirin and nitroglycerin for ACS patients. However, there is no clear evidence to support this. We investigated the benefits and harms of prehospital administration of aspirin and nitroglycerin by non-physician healthcare professionals in patients with suspected ACS. Methods and Results: We searched the PubMed database and used the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to assess the certainty of evidence. Three retrospective studies for aspirin and 1 for nitroglycerin administered in the prehospital setting to patients with acute myocardial infarction were included. Prehospital aspirin administration was associated with significantly lower 30-day and 1-year mortality compared with aspirin administration after arrival at hospital, with odds ratios (OR) of 0.59 (95% confidence interval [CI] 0.35-0.99) and 0.47 (95% CI 0.36-0.62), respectively. Prehospital nitroglycerin administration was also associated with significantly lower 30-day and 1-year mortality compared with no prehospital administration (OR 0.34 [95% CI 0.24-0.50] and 0.38 [95% CI 0.29-0.50], respectively). The certainty of evidence was very low in both systematic reviews. Conclusions: Our systematic reviews suggest that prehospital administration of aspirin and nitroglycerin by non-physician healthcare professionals is beneficial for patients with suspected ACS, although the certainty of evidence is very low. Further investigation is needed to determine the benefit of the prehospital administration of these agents.

Prehospital Activation of the Catheterization Laboratory Among Patients With Suspected ST-Elevation Myocardial Infarction Outside of a Hospital　- Systematic Review and Meta-Analysis.

Background: In the management of patients with ST-elevation myocardial infarction (STEMI), system delays for reperfusion therapy are still a matter of concern. We investigated the impact of prehospital activation of the catheterization laboratory in the management of STEMI patients. Methods and Results: This is a systematic review of observational studies. A search was conducted of the PubMed database from inception to July 2020 to identify articles for inclusion in the study. The critical outcomes were short- and long-term mortality. The important outcome was door-to-balloon time. The GRADE approach was used to assess the certainty of the evidence. Seven studies assessed short-term mortality; 1,541 were assigned to the prehospital activation (PH) group and 1,191 were assigned to the emergency department activation (ED) group. There were 26 fewer deaths per 1,000 patients in the PH group. Three studies assessed long-term mortality; 713 patients were assigned to the PH group and 1,026 were assigned to the ED group. There were 54 fewer deaths per 1,000 patients among the PH group. Five studies assessed door-to-balloon time; 959 were assigned to the PH group and 631 to the ED group. Door-to-balloon time was 33.1 min shorter in the PH group. Conclusions: Prehospital activation of the catheterization laboratory resulted in lower mortality and shorter door-to-balloon time for patients with suspected STEMI outside of a hospital.

Supplemental Oxygen and Acute Myocardial Infarction　- A Systematic Review and Meta-Analysis.

Background: In Japan, oxygen is commonly administered during the acute phase of myocardial infarction (MI) to patients without oxygen saturation monitoring. In this study we assessed the effects of supplemental oxygen therapy, compared with ambient air, on mortality and cardiac events by synthesizing evidence from randomized controlled trials (RCTs) of patients with suspected or confirmed acute MI. Methods and Results: PubMed was systematically searched for full-text RCTs published in English before June 21, 2020. Two reviewers independently screened the search results and appraised the risk of bias. The estimates for each outcome were pooled using a random-effects model. In all, 2,086 studies retrieved from PubMed were screened. Finally, 7,322 patients from 9 studies derived from 4 RCTs were analyzed. In-hospital mortality in the oxygen and ambient air groups was 1.8% and 1.6%, respectively (risk ratio [RR] 0.90; 95% confidence interval [CI] 0.38-2.10]); 0.8% and 0.5% of patients, respectively, experienced recurrent MI (RR 0.44; 95% CI 0.12-1.54), 1.5% and 1.6% of patients, respectively, experienced cardiac shock (RR 1.10; 95% CI 0.77-1.59]), and 2.4% and 2.0% of patients, respectively, experienced cardiac arrest (RR 0.91; 95% CI 0.43-1.94). Conclusions: Routine supplemental oxygen administration may not be beneficial or harmful, and high-flow oxygen may be unnecessary in normoxic patients in the acute phase of MI.

Systematic Review and Meta-Analysis of Diagnostic Accuracy to Identify ST-Segment Elevation Myocardial Infarction on Interpretations of Prehospital Electrocardiograms.

Background: The aim of this study was to assess and discuss the diagnostic accuracy of prehospital ECG interpretation through systematic review and meta-analyses. Methods and Results: Relevant literature published up to July 2020 was identified using PubMed. All human studies of prehospital adult patients suspected of ST-segment elevation myocardial infarction in which prehospital electrocardiogram (ECG) interpretation by paramedics or computers was evaluated and reporting all 4 (true-positive, false-positive, false-negative, and true-negative) values were included. Meta-analyses were conducted separately for the diagnostic accuracy of prehospital ECG interpretation by paramedics (Clinical Question [CQ] 1) and computers (CQ2). After screening, 4 studies for CQ1 and 6 studies for CQ2 were finally included in the meta-analysis. Regarding CQ1, the pooled sensitivity and specificity were 95.5% (95% confidence interval [CI] 82.5-99.0%) and 95.8% (95% CI 82.3-99.1%), respectively. Regarding CQ2, the pooled sensitivity and specificity were 85.4% (95% CI 74.1-92.3%) and 95.4% (95% CI 87.3-98.4%), respectively. Conclusions: This meta-analysis suggests that the diagnostic accuracy of paramedic prehospital ECG interpretations is favorable, with high pooled sensitivity and specificity, with an acceptable estimated number of false positives and false negatives. Computer-assisted ECG interpretation showed high pooled specificity with an acceptable estimated number of false positives, whereas the pooled sensitivity was relatively low.

Performance of the 0-Hour/1-Hour Algorithm for Diagnosing Myocardial Infarction in Patients With Chest Pain in the Emergency Department　- A Systematic Review and Meta-Analysis.

Background: This study assessed the diagnostic performance of the 0-hour/1-hour (0/1-h) algorithm to rule in and rule out acute myocardial infarction (MI) in patients presenting to the emergency department (ED) for suspected acute coronary syndrome without ST-segment elevation, as recommended in the 2015 European Society of Cardiology (ESC) guideline. Methods and Results: Following the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy (PRISMA-DTA) guidelines, a systematic review was conducted using the PubMed database from inception to March 31, 2020. We included any article published in English investigating the diagnostic performance of the ESC 0/1-h algorithm for diagnosing MI in patients with chest pain visiting the ED. Of 651 studies identified as potentially available for the study, 7 studies including 16 databases were analyzed. A meta-analysis of the diagnostic accuracy of the 0/1-h algorithm using high-sensitivity cardiac troponin I (hs-cTn) with 6 observational databases showed a pooled sensitivity of 99.3% (95% confidence interval [CI] 98.5-99.7%) and a pooled specificity of 90.1% (95% CI 80.7-95.2%). A meta-analysis of the diagnostic accuracy of 10 observational databases of the ESC 0/1-h algorithm using hs-cTn revealed a pooled sensitivity of 99.3% (95% CI 96.9-99.9%) and a pooled specificity of 91.7% (95% CI 83.5-96.1%). Conclusions: Our results demonstrate that the ESC 0/1-h algorithm can effectively rule in and rule out patients with non-ST-segment elevation MI.

Impact of Prehospital 12-Lead Electrocardiography and Destination Hospital Notification on Mortality in Patients With Chest Pain　- A Systematic Review.

Background: To achieve early reperfusion therapy for ST-elevation myocardial infarction (STEMI), proper and prompt patient transportation and activation of the catheterization laboratory are required. We investigated the efficacy of prehospital 12-lead electrocardiogram (ECG) acquisition and destination hospital notification in patients with STEMI. Methods and Results: This is a systematic review of observational studies. We searched the PubMed database from inception to March 2020. Two reviewers independently performed literature selection. The critical outcome was short-term mortality. The important outcome was door-to-balloon (D2B) time. We used the GRADE approach to assess the certainty of the evidence. For the critical outcome, 14 studies with 29,365 patients were included in the meta-analysis. Short-term mortality was significantly lower in the group with prehospital 12-lead ECG acquisition and destination hospital notification than in the control group (odds ratio 0.72; 95% confidence interval [CI] 0.61-0.85; P<0.0001). For the important outcome, 10 studies with 2,947 patients were included in the meta-analysis. D2B time was significantly shorter in the group with prehospital 12-lead ECG acquisition and destination hospital notification than in the control group (mean difference -26.24; 95% CI -33.46, -19.02; P<0.0001). Conclusions: Prehospital 12-lead ECG acquisition and destination hospital notification is associated with lower short-term mortality and shorter D2B time than no ECG acquisition or no notification among patients with suspected STEMI outside of a hospital.

GDF5+ chondroprogenitors derived from human pluripotent stem cells preferentially form permanent chondrocytes.

It has been established in the mouse model that during embryogenesis joint cartilage is generated from a specialized progenitor cell type, distinct from that responsible for the formation of growth plate cartilage. We recently found that mesodermal progeny of human pluripotent stem cells gave rise to two types of chondrogenic mesenchymal cells in culture: SOX9+ and GDF5+ cells. The fast-growing SOX9+ cells formed in vitro cartilage that expressed chondrocyte hypertrophy markers and readily underwent mineralization after ectopic transplantation. In contrast, the slowly growing GDF5+ cells derived from SOX9+ cells formed cartilage that tended to express low to undetectable levels of chondrocyte hypertrophy markers, but expressed PRG4, a marker of embryonic articular chondrocytes. The GDF5+-derived cartilage remained largely unmineralized in vivo. Interestingly, chondrocytes derived from the GDF5+ cells seemed to elicit these activities via non-cell-autonomous mechanisms. Genome-wide transcriptomic analyses suggested that GDF5+ cells might contain a teno/ligamento-genic potential, whereas SOX9+ cells resembled neural crest-like progeny-derived chondroprogenitors. Thus, human pluripotent stem cell-derived GDF5+ cells specified to generate permanent-like cartilage seem to emerge coincidentally with the commitment of the SOX9+ progeny to the tendon/ligament lineage.

Native T1 heterogeneity for predicting reverse remodeling in patients with non-ischemic dilated cardiomyopathy.

A recent study has shown that the heterogeneity of native T1 mapping may be a new prognostic factor for patients with non-ischemic dilated cardiomyopathy (NIDCM). This study aimed to investigate the predictive value of native T1 heterogeneity of the left ventricular (LV) myocardium, as assessed by pixel-wise histogram analysis, for predicting left ventricular reverse remodeling (LVRR) by medical therapy in patients with NIDCM. A total of one hundred and thirteen NIDCM patients (mean age: 63 ± 12 years; 91 males and 22 females; mean LV ejection fraction (EF): 37 ± 10%) were retrospectively analyzed. T1 mapping images were acquired using a modified look-locker inversion recovery (MOLLI) sequence. We performed histogram analysis of native T1 mapping of LV myocardium, mean (T1-mean) and standard deviation (T1-STD) of native T1 time from each pixel were calculated. Extracellular volume fraction (ECV) was also evaluated. LVRR was defined as LVEF increased ≥ 10% points and decrease in LV end-diastolic volume ≥ 10% at 12 months from initiation of medical therapy. Cutoff value of T1-mean and T1-STD was set as median value of each parameter. Sixty (53%) NIDCM patients reached LVRR. Area under the receiver-operating characteristics curve for predicting LVRR was 0.763 (95% confidence interval (CI) 0.679-0.847) for %LGE, 0.757 (95% CI 0.663-0.850) for T1-mean, 0.724 (95% CI 0.625-0.823) for T1-STD, 0.800 (95% CI 0.717-0.882) for ECV, respectively. Proportion of LVRR was significantly lower in NIDCM patients with high T1-mean and high T1-STD (12%) compared to NIDCM with high T1-mean and low T1-STD (65%) (p < 0.001). Adding T1-STD to T1-mean improved AUC from 0.757 to 0.806, comparable to AUC of ECV. Combination of T1-mean and T1-STD, a parameter of heterogeneity of native T1 of the LV myocardium, may be a useful for prediction of LVRR by medical therapy without use of gadolinium contrast for patients with NIDCM.