Artificial intelligence-assisted interpretation of systolic function by echocardiogram

Objective: Precise and reliable echocardiographic assessment of left ventricular ejection fraction (LVEF) is needed for clinical decision-making. Recently, artificial intelligence (AI) models have been developed to estimate LVEF accurately. The aim of this study was to evaluate whether an AI model could estimate an expert read of LVEF and reduce the interinstitutional variability of level 1 readers with the AI-LVEF displayed on the echocardiographic screen. Methods: This prospective, multicentre echocardiographic study was conducted by five cardiologists of level 1 echocardiographic skill (minimum level of competency to interpret images) from different hospitals. Protocol 1: Visual LVEFs for the 48 cases were measured without input from the AI-LVEF. Protocol 2: the 48 cases were again shown to all readers with inclusion of AI-LVEF data. To assess the concordance and accuracy with or without AI-LVEF, each visual LVEF measurement was compared with an average of the estimates by five expert readers as a reference. Results: A good correlation was found between AI-LVEF and reference LVEF (r=0.90, p<0.001) from the expert readers. For the classification LVEF, the area under the curve was 0.95 on heart failure with preserved EF and 0.96 on heart failure reduced EF. For the precision, the SD was reduced from 6.1±2.3 to 2.5±0.9 (p<0.001) with AI-LVEF. For the accuracy, the root-mean squared error was improved from 7.5±3.1 to 5.6±3.2 (p=0.004) with AI-LVEF. Conclusions: AI can assist with the interpretation of systolic function on an echocardiogram for level 1 readers from different institutions

AI for Exercise-Induced Pulmonary Hypertension

Background: Stress echocardiography is an emerging tool used to detect exercise-induced pulmonary hypertension (EIPH). However, facilities that can perform stress echocardiography are limited by issues such as cost and equipment. Objective: We evaluated the usefulness of a deep learning (DL) approach based on a chest X-ray (CXR) to predict EIPH in 6-min walk stress echocardiography. Methods: The study enrolled 142 patients with scleroderma or mixed connective tissue disease with scleroderma features who performed a 6-min walk stress echocardiographic test. EIPH was defined by abnormal cardiac output (CO) responses that involved an increase in mean pulmonary artery pressure (mPAP). We used the previously developed AI model to predict PH and calculated PH probability in this cohort. Results: EIPH defined as ΔmPAP/ΔCO >3.3 and exercise mPAP >25 mmHg was observed in 52 patients, while non-EIPH was observed in 90 patients. The patients with EIPH had a higher mPAP at rest than those without EIPH. The probability of PH based on the DL model was significantly higher in patients with EIPH than in those without EIPH. Multivariate analysis showed that gender, mean PAP at rest, and the probability of PH based on the DL model were independent predictors of EIPH. A model based on baseline parameters (age, gender, and mPAP at rest) was improved by adding the probability of PH predicted by the DL model (AUC: from 0.65 to 0.74; p = 0.046). Conclusion: Applying the DL model based on a CXR may have a potential for detection of EIPH in the clinical setting

Deep learning approach for analyzing chest x-rays to predict cardiac events in heart failure

Background: A deep learning (DL) model based on a chest x-ray was reported to predict elevated pulmonary artery wedge pressure (PAWP) as heart failure (HF). Objectives: The aim of this study was to (1) investigate the role of probability of elevated PAWP for the prediction of clinical outcomes in association with other parameters, and (2) to evaluate whether probability of elevated PAWP based on DL added prognostic information to other conventional clinical prognostic factors in HF. Methods: We evaluated 192 patients hospitalized with HF. We used a previously developed AI model to predict HF and calculated probability of elevated PAWP. Readmission following HF and cardiac mortality were the primary endpoints. Results: Probability of elevated PAWP was associated with diastolic function by echocardiography. During a median follow-up period of 58 months, 57 individuals either died or were readmitted. Probability of elevated PAWP appeared to be associated with worse clinical outcomes. After adjustment for readmission score and laboratory data in a Cox proportional-hazards model, probability of elevated PAWP at pre-discharge was associated with event free survival, independent of elevated left atrial pressure (LAP) based on echocardiographic guidelines (p < 0.001). In sequential Cox models, a model based on clinical data was improved by elevated LAP (p = 0.005), and increased further by probability of elevated PAWP (p < 0.001). In contrast, the addition of pulmonary congestion interpreted by a doctor did not statistically improve the ability of a model containing clinical variables (compared p = 0.086). Conclusions: This study showed the potential of using a DL model on a chest x-ray to predict PAWP and its ability to add prognostic information to other conventional clinical prognostic factors in HF. The results may help to enhance the accuracy of prediction models used to evaluate the risk of clinical outcomes in HF, potentially resulting in more informed clinical decision-making and better care for patients

Expression of alpha smooth muscle actin in living donor liver transplant recipients

Recently, there have been reports from liver biopsies that showed the progression of liver fibrosis in liver transplant patients after the cessation of immunosuppression. Herein, we focused on activated hepatic stellate cells expressing alpha smooth muscle actin (α-SMA) to understand the correlation between immunosuppressant medication and liver fibrosis. The study enrolled two pediatric patients who underwent living donor liver transplantation and ceased immunosuppressant therapy. The number of α-SMA-positive cells in the specimens obtained by liver biopsy from these two patients showed a three-fold increase compared with the number from four transplanted pediatric patients who were continuing immunosuppressant therapy. In addition, the α-SMA-positive area evaluated using the Win- RooF image processing software program continued to increase over time in three adult transplanted patients with liver fibrosis, and the α-SMA-positive area was increasing even during the pre-fibrotic stage in these adult cases, according to a retrospective review. Therefore, α-SMA could be a useful marker for the detection of early stage fibrosis

Complete response to pembrolizumab in advanced hepatocellular carcinoma with microsatellite instability

Hepatocellular carcinoma (HCC) has limited systemic treatment options and a poor prognosis. The immune checkpoint inhibitor pembrolizumab was recently approved for the treatment of solid tumors with microsatellite instability (MSI). However, its clinical utility for the management of HCC remains to be clarified. Here, we present a case of unresectable HCC with MSI that showed an impressive response to pembrolizumab treatment. A 64-year-old man with chronic HCV infection was diagnosed with a large HCC. His severe liver dysfunction and poor performance status prevented any treatment option other than sorafenib. However, sorafenib failed after a few days due to the rapid progression of the tumor. Based on the finding of MSI in a biopsy specimen, immunotherapy using pembrolizumab was initiated. A dramatic improvement in his general condition and a reduction in tumor size were observed after the initiation of pembrolizumab treatment. Among a cohort of 50 consecutive patients with advanced HCC who were refractory to standard systemic therapy, MSI was found only in the present case. Immune checkpoint blockade therapy induced prominent anti-tumor effects in HCC with MSI. Screening for defects in DNA mismatch repair function may be warranted in HCC patients despite the low frequency of MSI

頭寒足熱の温熱生理学的検証

Biological responses due to thermal stimuli were categorized based on the areas of the human body as well as on the modalities of thermal stresses such as icing, cooling and heating applications. These biological responses reported in previous papers were analyzed based on the concepts of Selective Brain Cooling (SBC) and long-term fever range (FR)-mild hyperthermia. Although no thermophysiological problems occurred in the case reports of biological responses induced by SBC, the effects of those induced by cooling of the body trunk and extremities were not so thoroughly evaluated. On the other hand, the idea of long-term fever range (FR)-mild hyperthermia (39.5-41.0℃) proved to be helpful in therapies enhancing the immune defenses against virulent bacterial diseases through the proliferation of Langerhans cells (LCs) and, under these conditions, it might even be beneficially combined with Selective Brain Cooling (SBC) and body heating to enhance human health and physical performance

La politique nucléaire du Japon

L'auteur examine ici quels bénéfices et quels désavantages aurait le Japon à acquérir un armement nucléaire, et conclut en souhaitant que tout en gardant la possibilité de devenir un jour une force nucléaire, le Japon joue discrètement de cette possibilité, en politique étrangère, mais devienne avant tout un grand pays, ses savants et ses technologues étant mis au service de son développement économique.Kosaka Masataka. La politique nucléaire du Japon. In: Politique étrangère, n°4 - 1973 - 38ᵉannée. pp. 485-502