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The vast majority of patients with acute occlusion of the proximal left anterior descending coronary artery (LAD) suffer frank ST-elevation myocardial infarction (STEMI). In contrast, a small but not insignificant minority presents with an electrocardiographic (ECG) pattern termed the "de Winter sign." The de Winter sign is characterized by upsloping ST depression followed by tall and peaked T waves in the precordial leads. The purpose of this report is to present two cases of acute obstruction of a large wrap-around LAD where the ECGs simultaneously displayed diagnostic criteria both for STEMI and the de Winter sign. We provide possible explanations for this hitherto undescribed phenomenon. [ABSTRACT FROM AUTHOR]

Nonalcoholic fatty liver disease (NAFLD) has emerged as a public health concern. To date, the mechanism of NAFLD progression remains unclear, and pharmacological treatment options are scarce. Traditional animal NAFLD models are limited in helping address these problems due to interspecies differences. Liver chips are promising for modeling NAFLD. However, pre-existing liver chips cannot reproduce complex physicochemical microenvironments of the liver effectively; thus, NAFLD modeling based on these chips is incomplete. Herein, we develop a biomimetic liver lobule chip (LC) and then establish a more accurate on-chip NAFLD model. The self-developed LC achieves dual blood supply through the designed hepatic portal vein and hepatic artery and the microtissue cultured on the LC forms multiple structures similar to in vivo liver. Based on the LC, NAFLD is modeled. Steatosis is successfully induced and more importantly, changing lipid zonation in a liver lobule with the progression of NAFLD is demonstrated for the first time on a microfluidic chip. In addition, the application of the induced NAFLD model has been preliminarily demonstrated in the prevention and reversibility of promising drugs. This study provides a promising platform to understand NAFLD progression and identify drugs for treating NAFLD. Liver chips are promising for modeling nonalcoholic fatty liver disease. However, on-chip replicating liver physicochemical microenvironments is still a challenge. Herein, we developed a liver lobule chip with dual blood supply, achieving self-organized liver microtissue that is similar to in vivo tissue. Based on the chip, we successfully modeled NAFLD under physiologically differentiated nutrient supplies. For the first time, the changing lipid zonation in a single liver lobule with the early-stage progression of NAFLD was demonstrated on a liver chip. This study provides a promising platform for modeling liver-related diseases. [Display omitted] [ABSTRACT FROM AUTHOR]

Pulmonary perfusion with dynamic contrast‐enhanced (DCE‐) MRI is typically assessed using a single‐input tracer kinetic model. Preliminary studies based on perfusion CT are indicating that dual‐input perfusion modeling of lung tumors may be clinically valuable as lung tumors have a dual blood supply from the pulmonary and aortic system. This study aimed to investigate the feasibility of fitting dual‐input tracer kinetic models to DCE‐MRI datasets of thoracic malignancies, including malignant pleural mesothelioma (MPM) and nonsmall cell lung cancer (NSCLC), by comparing them to single‐input (pulmonary or systemic arterial input) tracer kinetic models for the voxel‐level analysis within the tumor with respect to goodness‐of‐fit statistics. Fifteen patients (five MPM, ten NSCLC) underwent DCE‐MRI prior to radiotherapy. DCE‐MRI data were analyzed using five different single‐ or dual‐input tracer kinetic models: Tofts‐Kety (TK), extended TK (ETK), two compartment exchange (2CX), adiabatic approximation to the tissue homogeneity (AATH) and distributed parameter (DP) models. The pulmonary blood flow (BF), blood volume (BV), mean transit time (MTT), permeability‐surface area product (PS), fractional interstitial volume (vI), and volume transfer constant (KTrans) were calculated for both single‐ and dual‐input models. The pulmonary arterial flow fraction (γ), pulmonary arterial blood flow (BFPA) and systemic arterial blood flow (BFA) were additionally calculated for only dual‐input models. The competing models were ranked and their Akaike weights were calculated for each voxel according to corrected Akaike information criterion (cAIC). The optimal model was chosen based on the lowest cAIC value. In both types of tumors, all five dual‐input models yielded lower cAIC values than their corresponding single‐input models. The 2CX model was the best‐fitted model and most optimal in describing tracer kinetic behavior to assess microvascular properties in both MPM and NSCLC. The dual‐input 2CX‐model‐derived BFA was the most significant parameter in differentiating adenocarcinoma from squamous cell carcinoma histology for NSCLC patients. [ABSTRACT FROM AUTHOR]

Objective: To describe a new CT perfusion technique for assessing the dual blood supply in lung cancer and present the initial results. Methods: This study was approved by the institutional review board. A CT protocol was developed, and a dual-input CT perfusion (DI-CTP) analysis model was applied and evaluated regarding the blood flow fractions in lung tumours. The pulmonary trunk and the descending aorta were selected as the input arteries for the pulmonary circulation and the bronchial circulation respectively. Pulmonary flow (PF), bronchial flow (BF), and a perfusion index (PI, = PF/ (PF + BF)) were calculated using the maximum slope method. After written informed consent was obtained, 13 consecutive subjects with primary lung cancer underwent DI-CTP. Results: Perfusion results are as follows: PF, 13.45 ± 10.97 ml/min/100 ml; BF, 48.67 ± 28.87 ml/min/100 ml; PI, 21 % ± 11 %. BF is significantly larger than PF, P < 0.001. There is a negative correlation between the tumour volume and perfusion index ( r = 0.671, P = 0.012). Conclusion: The dual-input CT perfusion analysis method can be applied successfully to lung tumours. Initial results demonstrate a dual blood supply in primary lung cancer, in which the systemic circulation is dominant, and that the proportion of the two circulation systems is moderately dependent on tumour size. Key Points: [ABSTRACT FROM AUTHOR]

Quantification of the 11C-acetate liver studies with dynamic positron emission tomography (PET) could significantly improve the evaluation of hepatocellular carcinoma (HCC), where both time-activity curves (TACs) of the hepatic artery (HA) and portal vein (PV) (the dual hepatic blood supply) are required. However, directly measuring them by the blood sampling or cannulation procedure is very invasive. In addition, it is very hard to differentiate the PV from the surrounding liver tissue on PET images by the currently developed indirect methods. To noninvasively and efficiently access the TAC of PV, we investigated the possibility of modeling the dual hepatic blood supply and presented two hepatic dual-input (DI) models. Combining the established 11C-acetate liver model with two different DI models, we obtained two dual-models with six/seven parameters to fit the dynamic PET measurements. The fitting results were compared with those of the 11C-acetate liver model using image-derived dual hepatic inputs (the "Golden standard") by statistical study. The adequacy of the two dual-models was estimated by Akaike Information Criteria (AIC) and Schwarz Criteria (SC). It was revealed that the proposed modeling technique could successfully account for the hepatic dual blood supply and the six-parameter (6-P) dual-model is more suitable for quantification of 11C-acetate liver studies. [ABSTRACT FROM PUBLISHER]

Background: In recent years, the detection rate of ground-glass nodules (GGNs) has been improved dramatically due to the popularization of low-dose computed tomography (CT) screening with high-resolution CT technique. This presents challenges for the characterization and management of the GGNs, which depends on a thorough investigation and sufficient diagnostic knowledge of the GGNs. In most diagnostic studies of the GGNs, morphological manifestations are used to differentiate benignancy and malignancy. In contrast, few studies are dedicated to the assessment of the hemodynamics, i.e. , perfusion parameters of the GGNs., Aim: To assess the dual vascular supply patterns of GGNs on different histopathology and opacities., Methods: Forty-seven GGNs from 47 patients were prospectively included and underwent the dynamic volume CT. Histopathologic diagnoses were obtained within two weeks after the CT examination. Blood flow from the bronchial artery [bronchial flow (BF)] and pulmonary artery [pulmonary flow (PF)] as well as the perfusion index (PI) = [PF/(PF + BF)] were obtained using first-pass dual-input CT perfusion analysis and compared respectively between different histopathology and lesion types (pure or mixed GGNs) and correlated with the attenuation values of the lesions using one-way ANOVA, student's t test and Pearson correlation analysis., Results: Of the 47 GGNs (mean diameter, 8.17 mm; range, 5.3-12.7 mm), 30 (64%) were carcinoma, 6 (13%) were atypical adenomatous hyperplasia and 11 (23%) were organizing pneumonia. All perfusion parameters (BF, PF and PI) demonstrated no significant difference among the three conditions (all P > 0.05). The PFs were higher than the BFs in all the three conditions (all P < 0.001). Of the 30 GGN carcinomas, 14 showed mixed GGNs and 16 pure GGNs with a higher PI in the latter ( P < 0.01). Of the 17 benign GGNs, 4 showed mixed GGNs and 13 pure GGNs with no significant difference of the PI between the GGN types ( P = 0.21). A negative correlation ( r = -0.76, P < 0.001) was demonstrated between the CT attenuation values and the PIs in the 30 GGN carcinomas., Conclusion: The GGNs are perfused dominantly by the PF regardless of its histopathology while the weight of the BF in the GGN carcinomas increases gradually during the progress of its opacification., Competing Interests: Conflict-of-interest statement: The authors of this manuscript having no conflicts of interest to disclose., (©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.)

To study resectability and regeneration of cirrhotic liver, hemodynamic changes following partial hepatectomy were observed in dogs with presinusoidal block caused by ligation of the portal vein or with postsinusoidal block caused by ligation of the hepatic veins after portacaval anastomosis, since cirrhosis of the liver in man is mainly of postsinusoidal block occasionally accompanied by presinusoidal block. With a presinusoidal block, resection of 50 per cent liver was tolerated well, but with postsinusoidal block only less than 30 per cent could be resected. Thus the functional reserve of the liver with postsinusoidal block seems to be much less than that of presinusoidal block. After major hepatic resection the weight of the remnant liver with a dual blood supply increased markedly, while with a postsinusoidal block it increased slightly and with a presinusoidal block there was no change. Histometric studies showed that regeneration was prominent in the remnant liver with a dual blood supply, slight with a postsinusoidal block, and even less with a presinusoidal block. Thus, the liver with a postsinusoidal block possesses more extensive regenerative capacity but shows much lower resectability than with a presinusoidal block. Therefore, the resectability of the liver associated with cirrhosis seems to be more closely related to its functional reserve capacity than to its regenerative capacity. [ABSTRACT FROM AUTHOR]