This study aims to construct a prediction model for histological chorioamnionitis (HCA) and analyze the associations between the predicted risk of HCA and adverse outcomes in preterm infants.n = 195) and non-HCA group (n = 478). A stepwise method was used to screen the predictors for HCA, binary logistic regression was used to construct the prediction model, and the associations between the predicted risk of HCA and adverse outcomes were analyzed.In total, 673 subjects were included in this cohort study and divided into HCA group : 0.767–0.874)], the specificity was 0.684 (95% CI: 0.642–0.726), the positive predictive value was 0.514 (0.459–0.570), the negative predictive value was 0.903 (95% CI: 0.873–0.934), the area under the curve was 0.821 (95% CI: 0.786–0.855), and the accuracy was 0.724 (95% CI: 0.690–0.757). The predicted risk of HCA was associated with a higher risk of bronchopulmonary dysplasia (BPD) , sepsis , and neonatal infections , but not necrotizing enterocolitis , retinopathy of prematurity , and brain damage . After adjusting for confounders including gestational week at birth and birth weight, the risk of neonatal infections  was increased in preterm infants’ exposure to HCA.The model showed good predictive performance for identifying pregnant women with a higher risk of HCA. In addition, HCA was associated with the risk of BPD, sepsis, and infections in neonates. Chorioamnionitis (CA) is an acute inflammation of the amnion and chorion, serving as an indicator for intra-amniotic infection . CA is fStrong evidence supported that HCA is associated with adverse neonatal morbidities in preterm birth including newborn respiratory distress syndrome (NRDS), sepsis, bronchopulmonary dysplasia (BPD), and death , 8. WattIn the current study, the risk of HCA was predicted via constructing a prediction model, and the associations between the predicted risk of HCA and the adverse outcomes in preterm infants were analyzed.n = 72). The pathology of placenta was examined in 933 subjects. Among them, 36 patients were discharged on the first day on birth and were not followed-up. A total of 31 infants with dysontogenesis or chromosome abnormality were excluded. Those who could not been diagnosed whether they had HCA were not included (n = 21). Subjects who had twin and multiple premature infants were excluded (n = 156). Those with incomplete clinical data on maternal weight and height (n = 4), history of preterm birth (n = 3), gravidity (n = 1), maternal education level (n = 1), premature rupture time of membranes (n = 1), whether in vitro fertilization (IVF) was applied (n = 4), prenatal insulin use (n = 1), prenatal glucocorticoid use (n = 1), and prenatal maternal platelets (n = 1) were also excluded. Finally, 673 participants were included in this study. The detailed screen process was presented in n = 195) and non-HCA group (n = 478). The diagnosis of HCA was based on the results of pathology of placenta. The study was approved by the Ethics Committee of Northwest Women's and Children's Hospital (No. 2022-074), and all participants provided the informed consent form before enrollment.In this retrospective cohort study, we retrospectively collected the data of 1,433 subjects who delivered in the Department of Neonatology, Northwest Women's and Children's Hospital, between 1 June 2018 and 31 May 2020. Participants who had singleton pregnancy with live birth whose gestational age was <34 weeks were included. All infants were admitted to the Neonatal Department during the neonatal period. Patients with CCA were not included in this study (2), history of preterm birth, gravidity, parity, frequency of abortion, education , premature rupture of membranes or not, IVF or not, hypertension or not, diabetes or not, prenatal insulin use or not, prenatal antibiotic use or not, prenatal glucocorticoid use , prenatal use of magnesium sulfate or not, prenatal fever or not, duration of fever (h), increase of fetal heart rate or not, placental abruption or not, increase of maternal heart rate or not, placenta previa or not, white blood cells , neutrophil percentage (NEUT%), lymphocyte ratio (LYM%), neutrophil-to-lymphocyte ratio (NLR), hemoglobin (g/L), platelet (109/L), CRP , albumin (g/L), Group B streptococcus , vaginitis during pregnancy or not, oligohydramnios or not, complications of diabetes or hypertension or not, cholestasis or not, abnormal fetal heart rate or not, length of placenta, width of placenta, thickness of placenta, and fetal distress.The demographic and clinical data of the pregnant mothers were collected including age, body mass index  at >21 was required for a duration of 28 days or longer , sepsis, retinopathy of prematurity (ROP), brain damage, neonatal infection, or death in preterm newborns. Brain damage was diagnosed based on brain B ultrasound or brain magnetic resonance imaging after 72 h–96 h of birth. ROP was screened 4–6 weeks after birth. A diagnosis of BPD was made when the administration of oxygen at a fraction of inspired oxygen ], and comparisons were conducted via Wilcoxon rank sum test. Qualitative data were shown as n (%), and the differences between groups were compared via chi-square test. Sensitivity analysis was performed to compare the data of the participants with and without placenta examination . An elevated risk of sepsis in preterm infants was also identified in those diagnosed with HCA . The risk of neonatal infections in preterm infants was increased in patients with HCA . After adjusting for confounders including gestational week at birth and birth weight, the risk of neonatal infections  was also increased in preterm infants’ exposure to HCA .This study collected the data of 673 subjects who delivered in Northwest Women’s and Children's Hospital for constructing a prediction model for HCA and evaluating the association between the predicted risk of HCA and the adverse outcomes in preterm infants as well as the risk of adverse outcomes in preterm infants in women with HCA. The prediction model showed good predictive performance for HCA. The predicted risk of HCA was associated with the risk of BPD, sepsis, and neonatal infections. HCA was associated with a higher risk of infections in infants. The findings of our study might quickly help identify those with a high risk of HCA, provide effective interventions on preventing the occurrence of HCA, and improve the outcomes of these patients.Previously, the premature rupture of membranes was identified to be a risk factor for HCA . HCA patThe logistic prediction model for HCA was constructed based on the data of 684 participants using the predictors including premature rupture of membranes, WBC, and maternal CRP levels. Previous prediction models were applied for identifying patients with a high risk of HCA in those with premature rupture of membranes , 24–26. In China, some women would like to bring their placenta home and deal with it by themselves according to their custom. They did not want to exam their placenta. Some of the HCA cases might be missed. Moreover, the results of placenta pathology were available approximately 3 days in some hospital, and this might cause a delay of the treatment of infants. For infants with predicted high risk of HCA exposure, the evaluation should be done in a timely manner, and timely treatments should be provided. Our prediction model using non-invasive biological markers, which are to use, and their results are readily available.Staphylococcus epidermidis and increase the risk of sepsis in neonates (In the current study, a higher risk of HCA was associated with an elevated risk of BPD. This was allied by a meta-analysis by Villamor-Martinez, indicating that exposure to CA was associated with a higher risk of BPD in preterm infants . CA-induneonates .Currently, for HCA-exposed infants, empirical antibiotic therapy was recommended as a guideline for the treatment of these patients, but some clinicians question these recommendations due to the potential antibiotic risks . AnotherSeveral limitations in our study were reported. First, this was a retrospective cohort study, and the information on the participants might have bias. Second, no external validation was performed to verify the prediction model in this study. Third, there might be missing data bias, as not every placenta was examined in our participants. In the future, well-designed prospective studies with a large scale of sample size are required to validate the result in the current study.The data of 673 subjects who delivered in Northwest Women’s and Children's Hospital were used to establish a prediction model for HCA in this study. The model showed good predictive performance for identifying pregnant women with a higher risk of HCA. In addition, the predicted risk of HCA was associated with the risk of BPD, sepsis, and infections in neonates. The findings of our study might help early identify those who have a high risk of HCA and provide timely interventions to improve the outcomes of infants.


Mycobacterium marinum infections are rare, and they can be difficult to diagnose and treat. This may lead to further spread of the infection and complications, such as tenosynovitis, pyomyositis, and osteomyelitis. A 40-year-old previously healthy man presented with tenosynovitis of the extensor tendons on the second phalanx of his right hand. He was initially treated with steroid injections without any effect. Followingly, ulceration and an abscess developed on the dorsal site of the hand. At this point, it came to the physician’s knowledge that the patient had been cleaning an aquarium before onset of symptoms. After progression to massive tenosynovitis, the patient was admitted and underwent multiple surgical debridements. Briefly, after the first surgery, an interferon-γ release assay was positive, and treatment for M. marinum with rifampicin and azithromycin was initiated after eight months of symptoms. Later, a surgical biopsy showed acid-fast bacilli, and a polymerase chain reaction confirmed the diagnosis of M. marinum. In this case story, we highlight the difficulties of diagnosing and managing this complicated infection, describe the considerable morbidity associated with it, and suggest that local tissue concentrations could be useful to improve clinical outcomes, as these concentrations are potentially suboptimal. Mycobacterium marinum infections are rare, with annual incidence rates ranging from 0.4–1.3 per 1,000,000 individuals [M. marinum are slowly growing acid-fast rods that grows at temperatures below 37 °C, belonging to the nontuberculous mycobacteria (NTM) species [ividuals . Still, ividuals . M. mari species . After t species . Most co species . A wide M. marinum is often around three weeks, but it may last up to nine months [M. marinum is detected using microscopy, polymerase chain reaction (PCR), and culturing using techniques that are specific for mycobacteria [M. marinum may be related to a higher risk of complicated infections, with spread to deeper tissues as joints and tendons, an early diagnosis is of utmost importance [The incubation period of e months . The lonbacteria . Since aportance .M. marinum-associated tenosynovitis after cleaning his aquarium. Initially, he was treated for degenerative tenosynovitis with steroid injections, but after eight months of symptom progression, the patient was finally diagnosed. The patient was treated successfully with extensive surgery with repeated infection debridement and antibiotics for six months.Here, we highlight the difficulties of diagnosing and managing this complicated infection in a patient with a protracted A 40-year-old man without any comorbidities, besides a previous gastric bypass surgery, was referred to the department of infectious diseases from the department of rheumatology on suspicion of tenosynovitis of an infectious origin. A timeline is shown in Two weeks after the symptoms began with the finger being swollen, tender, and warm , the patS. aureus was cultured from the wound. No acid-fast bacilli were found in the pus, and PCR did not show Mycobacterium tuberculosis complex DNA. At this point, the patient was referred to the department of infectious diseases.Four months after symptom onset, blood samples were still normal, including HLA-B27, RF-IgM, and anti-CCP . Seven mM. marinum. Following this, microscopy showed acid-fast bacilli, and a PCR confirmed the tentative diagnosis. Histology showed acute and chronic inflammation with non-necrotic granulomas. However, mycobacterial culture later came back negative.A new MRI, nearly eight months after symptom onset, showed severe progression of the tenosynovitis, involving, at this point, all extensor tendons of the dorsal side of the right hand with extensive fluid accumulation in the distended hypertrophic synovium . Bone maM. marinum was initially small, as the patient did not recall having any cutaneous lesions that could have been the bacterial site of entry. Fransicella tularensis was ruled out. However, over time, with the progression from swelling of one finger to the whole dorsum of the hand, the ulceration and abscess formation over the head of the second metacarpal, and especially the new information about scuba-diving activities and aquarium hobbies, the diagnosis of M. marinum infection seemed more and more obvious. Since S. aureus was cultured from the abscess, a second-generation cephalosporin  was administered intravenously at 1500 mg three times daily for one week after surgery without any improvement in clinical appearance of the infection site. Consequently, S. aureus was considered not to be the cause of disease.In the beginning, the patient was considered to have a degenerative tenosynovitis and was treated with steroid injections. At the department of rheumatology, there were initially no signs of inflammation at ultrasonographic examination leading to a suspicion of autoimmune disease, foreign body, or a slow infection. When the patient was referred to the department of infectious diseases, the suspicion of The patient was admitted for 10 days and had three rounds of surgical debridement before being discharged . One monM. marinum. The case demonstrates that the diagnosis is not easily made, and the treatment is complex and requires a multidisciplinary approach between medical and surgical specialists, as well as occupational therapists. Moreover, the case shows that these infections may be associated with a considerable morbidity .Here, we presented a case of massive infectious tenosynovitis of the hand caused by M. marinum most often cause skin lesions and have four predominant clinical manifestations: (1) superficial cutaneous lesions, (2) more than three lesions with a spreading pattern resembling sporotrichosis or abscesses and granulomas, (3) deeper infections, such as tenosynovitis (with or without cutaneous lesions), and (4) disseminated infections [M. marinum infections are seen in the upper extremity, involving hands and fingers (88.7–95%) [M. marinum is commonly seen specifically in the hand or wrist because of the higher risk of penetrating injury [Among NTM, lesions,  more thafections . As showtations:  superficlesions,  more tha8.7–95%) , which ilesions,  more tha8.7–95%) ,12. Tenog injury . One stug injury . Yet, thg injury . A cortig injury . This emg injury .M. marinum may be extensive. One study found that the median time between the first symptoms and diagnosis was 6.5 months [S. aureus. In line with this, S. aureus was cultured from the first inoculation of the abscess for the patient in our case. This could either be a contamination, colonization, or a disease-causing superinfection. However, the lesion did not improve when the patient was given cefuroxime intravenously. A similar case reported that suspicion of S. aureus or streptococci led to delay in diagnosis of M. marinum infection [M. marinum usually takes two to three weeks [n = 11/29) and 5.6–37.9% (n = 1/18 and 11/29) of patients had a positive PCR and culture [M. marinum infection is based on symptomatology with characteristic lesions and a relevant history of marine exposure, histopathology showing granulomas, microscopy, PCR, culturing proving mycobacteria, and on a response to appropriate treatment [The diagnostic delay for 5 months . In our nfection . First oee weeks ,11. Only culture , respectreatment . If maten = 10/29) were immunohistochemical positive, using a polyclonal antibody against Mycobacterium bovis with known cross-reactivity with a variety of mycobacteria, despite eight being culture-negative [Mycobacterium tuberculosis  [M. tuberculosis exposure. Yet, these antigens are also shared by a few NTM species , potentially leading to a positive result among some patients with NTM infection, as in our case [M. marinum, which is why the patient was started on treatment without a definitive diagnosis.Other diagnostic tools, such as immunohistochemistry, can be helpful. A study found that 34.5% (negative . Anotherd TB7.7) . Consequour case . The cliM. marinum infections is based on observational studies and in vitro studies showing susceptibility to rifamycins, macrolides, sulphonamides, trimethoprim, and ethambutol, but showing isoniazid and pyrazinamide resistance [M. marinum, as there are no implications of significant mutational drug resistance and no substantial variation of susceptibility. However, there have been isolates with ethambutol, minocycline, and fluoroquinolones resistance [The evidence for treating of sistance . For supsistance . Althougsistance . Routinesistance .M. marinum infections (23.5%) [One study found that deeper infections require considerably more surgical procedures 91.7%) compared with cutaneous 1.7% comp (23.5%) . If the  (23.5%) . More kn (23.5%) , but it  (23.5%) . Subopti (23.5%) , emphasi (23.5%)  wheneverThe long course to obtain the correct diagnosis and finalize treatment may also inflict other significant burdens on the patient. The whole course of disease typically results in numerous health care contacts and months of antibiotic treatment . The conM. marinum may cause complicated infections often with significant morbidity. The management is challenged by suboptimal diagnostic tools, delays in the diagnosis, a protracted effect of antimicrobial treatment, and a possible need of repeated surgery, which all together entails a risk of loss of hand function and lasting disability. More evidence is needed, and knowledge about local tissue concentrations could potentially be useful. Clinicians should be aware of M. marinum as a cause of slow and atypical skin and soft tissue infection. Possible aquatic exposures should be clarified initially, as they likely aid in a more direct diagnostic path. More research is warranted to improve diagnostics and treatment routes for M. marinum infections.In conclusion,


Interest is one of the main factors motivating an individual's behavior, and its effect in the learning process has been widely confirmed in educational psychology. The purpose of this study was to explore the influence of individual interest, topic interest and situational interest on the user's video click behavior in the online video browsing situation. We constructed an online experiment in which each participant was asked to use questionnaires to assess their responses to video categories, titles, and covers from the video-sharing website, Bilibili. Based on these responses, we obtained individual interests, topic interests, situational interests, and click behavior of the participants toward the videos. Correlation, regression and mediation analyses were conducted to explore the effects and mechanisms of the three interests on click behavior. The results found: (1) individual interest may have a positive but relatively weaker effect on click behavior, and (2) topic interest and situational interest positively predicted click behavior in all categories. The mediation analysis found: (1) in the otomads and fashion categories, the effect of individual interest on click behavior was partially mediated by topic and situational interest, and (2) in the anime, digits, life, dance, music, game, entertainment, and knowledge categories, the effect of individual interest on click behavior was fully mediated by topic interest and situational interest. These results revealed the facilitating effects and different effect modes of individual, topic, and situational interest on click behavior. These findings shed light on the influence mechanism of interests on video click behavior in different video categories and provide new insights into related applications such as recommender. When a user is browsing an online video-sharing platform, how does the information they receive prompt them to click and watch a certain video? This is a valuable question for both researchers and practitioners. In the field of information technology, recommendation algorithms can use the user's past click records as a label to build models to select new videos that are more likely to be clicked by the user Lv, . AlthougAs a psychological term, interest is defined as a motivational variable  all three interests can facilitate the occurrence of click behavior, and (2) the three interests are weighted differently and act in different ways in the click decision. The empirical evidence from these experiments may help us to better understand the cognitive process of online video selection and provide reference to recommendation research from a psychological perspective.n = 236) and 36.8% male subjects (n = 126). The average age was 22 (SD = 2.99), ranging from 18 to 44  are featured in Bilibili. Meanwhile, most of the page is occupied by video titles and video covers, which are matched in pairs and shown together. The video cover is a picture containing some visual elements of the video and the video title is located below the picture, stating the specific topic of the video by text . AccordiTo select the representative videos in the category, the study obtained the required materials from videos with almost 500,000 views within 7 days, which means that the video obtained moderate popularity. In each video category, the earliest six videos that met the criteria were selected as the materials representing the category by randomly refreshing the page, and finally, we obtained 60 videos in total (six for each category). To minimize possible bias while controlling the time cost for a single participant, all the participants were randomly divided into six groups. Each group was randomly assigned one video for each video category during the experiment, which means that the participants in different groups received different experimental materials and the participants in the same group received the same experimental materials.A short questionnaire was adapted from a personal interest scale Ainley, , which wAinley's Topic Interest Scale measures the level of topic interest by using only one item related to the title Ainley, . To measOur questionnaire to evaluate situational interest was similar to the above, consisting of the seven items but asking about specific video covers. Sample items included the following: “Seeing the cover of this video, I am interested in the cover:” and “Seeing the cover of this video, I think the video is interesting:” Also, a mean score was calculated from seven items.The probability of clicking on the video was reported by participants, ranging from 0 (must not click) to 100 (definitely will click).The study was conducted through an online webpage containing all the stimuli and questionnaires and made up of three main stages. Each participant would finish three questionnaires . First, As participants had already read all the titles in the second stage, and a video cover usually contained varying numbers of keywords of the title, we also presented the corresponding video title closely below each cover picture in the third stage. Considering the participant would process both topic-related and situation-related information in this circumstance, the final situational interest score was calculated by subtracting the topic interest score from the original situation interest score.To explore the effects of the different interests on click behavior, correlation analysis was first conducted to illustrate their basic relationship. Regression analysis was then used to determine which interest has a greater impact on click behavior. After that, we constructed a mediation model to further analyze the mechanism of interest's influence on click behavior. All these analyses were conducted by Jamovi 2.2.2.To analyze the relationships between different interests and click probabilities, we first conducted Pearson's correlation analysis on the whole sample, with one individual's response to a video as one case. Then the same analysis was conducted separately in each video category. Taking all samples into consideration, individual interest, topic interest, and situational interest were all significantly correlated with click behavior. In all categories, the relationship between interest and click behavior was consistent with the result of analysis on all samples, and in most categories, the correlation coefficient of the topic interest was higher than the other two interests (see results in t(122) = 2.35, p = 0.02] for male subjects, in the fashion category  for female subjects, and in the whole sample for female subjects , with a lower regression coefficient than the other two interests. The regression coefficients of topic interest and situational interest also varied in different categories.This study utilized the ordinary linear regression method to explore the relationship between different interests and click probability. Different interests were treated as the independent variable, gender of users as the control variable, and click probability as the dependent variable in our analysis. As shown in The results of correlation analysis showed the facilitative effects of all three interests on click behavior, while individual interest was not significant in the linear regression model in many video categories. To further explore how different types of interests affect click behavior in different video categories, we conducted mediation analyses. As one video category contains mass-specific videos, topic interest and situational interest triggered by a specific video may have more direct effects than the individual interest triggered by video categories. In this step, we explored whether topic interest and situational interest mediate the effect of individual interest on click behavior.For all samples, the topic interest partly mediates the effect of individual interest on click behavior which means the direct effect and the indirect effect is significant. Situational interest's mediating effect is not significant in statistics. The mediation analysis results also vary across categories. According to the relationship between individual interest and click behavior, the analysis results can be divided into two main types: partly mediating effect and full mediating effect (see results of each category in In the otomads and fashion categories, the relationship between individual interest and click behavior is partly mediated . More spIn the anime, digits life, dance, music, game, entertainment, and knowledge categories, the relationship between individual interest and click behavior is fully mediated . More spThrough correlation analysis, regression analysis, and mediation analysis, we explored the role of individual interest, topic interest, and situational interest on click behavior in online video browsing situations. For all samples and each category, the results of correlation analysis showed that individual interest, topic interest, and situational interest all had a significant positive relationship with click behavior. All three interests had a facilitative effect on click behavior, which supported our first preliminary hypothesis. This result was also consistent with the previous studies showing the effects of interest on learning (Ainley et al., The mediation analysis further revealed the influence pattern of the three interests on click behavior, and there were mainly two different patterns for different categories of videos.For the otomads and fashion categories, users' interest in the category did have an impact on the possibility of them clicking on the video. Users who follow these categories were more likely to click on videos in these categories, and at least part of that effect was independent of the title and cover of the video. This means that even though the specific content of the video does not really interest the user, there is a certain possibility that the user will click on the video. In these categories, the user's internal needs and knowledge reflected by individual interest played a role in facilitating the further exploration of a video, which was consistent with the role the individual interest played in learning studies (Fransson, For the anime, digits, life, dance, music, game, entertainment, and knowledge categories, the effect of individual interest was fully mediated by topic interest or situational interest, or both. The user's individual interest in these domains did affect the probability of clicking on a video in these categories, but that was essential because the domain interest predicted the interest in a specific video title or a specific video cover in this category. The topic interest and situational interest finally triggered click behavior, which means that for these categories, users might not click on a video if the specific content of the video does not interest them.Considering the results of all analyses together, we found that three types of interest had different predictive power on online video click behavior and revealed how they have an impact on click behavior, which supported the second hypothesis. In most video categories, topic interest plays the most important role in predicting click behavior, which means that the cognitive processing of the video title will greatly affect the occurrence of subsequent exploration behavior (Prestwich et al., Individual interest also has a significant effect on click behavior, which implies that the user's inherent preference and tendency will predict further exploration behavior (Perera and Zimmermann, The differences in the result patterns in different categories also provide us with more knowledge about the specific effects of interest. The results in the otomads category showed that situational interest was more important in predicting click behavior than topic interest. The reason for this phenomenon needs to be investigated from the characteristics of the video in the otomads category. Otomads refers to a kind of adapted video that subverts the classics, deconstructs the tradition, promotes the personality, strengthens the focus, and satirizes the society by dissecting social hot issues and then repeating and re-creating them. The video cover in otomads is often an adaption of the original video material to make it more entertaining. Thus, a prominent feature of the video covers in otomads is the use of richer colors and more exaggerated stickers, which could attract more attention from users. This may explain why situational interest in the otomads category plays a greater role in predicting click behavior.The mediation analysis in the otomads and fashion categories showed that individual interest not only promoted click behavior through situational interest or topic interest but also directly promoted click behavior. Such a direct effect was not found in other categories. This may be because the videos in the otomads and fashion categories are distinctive features that attract fans no matter what the specific video content is. Meanwhile, these features should be quite easy to recognize. Thus, the fans of the two categories could identify the otomads or fashion videos from the title and cover, and their desire to exploration could be aroused just by this fact.The effect of individual interest was mediated by topic interest in all categories but mediated by situational interest only in the otomads and anime categories. This means that individual interest can only have an impact on click behavior through situational interest in these two categories. The reason for this result may be that understanding the video cover content in these two categories requires some prior knowledge, which is not easy to obtain in daily life. The users with high individual interest have more prior knowledge about the content of the categories, so they could understand the video covers more easily. For those with low individual interest and less or no prior knowledge, they cannot fully process the visual elements in those covers.It should also be noted that the difference in the predictive powers of individual interest among categories may be caused by different reasons. One possible reason is that the impact of individual interest on click behavior really is different among categories. Another possible influencing factor is the difference in how a video title and cover reflect the category of the video. Although for most categories the title and cover could obviously show the video category, sometimes the title and cover may reflect the category information less clearly in some categories. When users processed titles and covers of different categories in our experiment, the difference in their capabilities of reflecting their categories may also lead to variations in the predictive power of individual interest. Thus, it is reasonable to be more cautious in understanding the difference in the predictive powers of individual interest among different categories.Today, the information overload prevalent on the internet means it is extremely valuable to get users' attention Renjith, , and cliAs a preliminary study, there are also some limitations that need to be noted. Although we have revealed the influence mechanism of different interests on click behavior, the reasons for the inconsistency of influence patterns in various categories are still unclear. This requires further analysis of the differences among video categories. Different categories of videos may differ in the “focus area” when they were produced (Bopp et al., In conclusion, we found that the theoretical division of interest in educational psychology could also be applicable to online video browsing situations. Individual interest, topic interest, and situational interest can promote click behavior to different degrees when users browse online videos, and topic interest generally has the greatest impact except for the otomads category. Topic and situational interests partially or completely mediated the effect of individual interests on click behavior, and the mediation effect varied among different categories. Our results could provide psychological perspectives of interest and click behavior to the recommendation and other relevant applications in the online social media scenario.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.The studies involving human participants were reviewed and approved by the Institute of Psychology, Chinese Academy of Sciences. The patients/participants provided their written informed consent to participate in this study.NZ contributed to the conception, the design of the study, and the manuscript writing. DL collected the data, performed most of the statistical analysis, and wrote the manuscript with input from all authors. ZT conducted part of the experiment and performed part of the statistical analysis. All authors contributed to the article and approved the submitted version.


Objectives: COVID-19 cases continue to climb in the community from the SARS-CoV-2 δ (delta) variant wave. To prepare for cases that may be nosocomial or detected late, the infection prevention team constructed a ‘hot ward’ tool kit to guide implementation of infection control measures. Methods: We engaged the NUH Facilities Management ventilation engineers to understand every ward’s mechanical ventilation setup. With this information, we created of “green” and “hot” zones within ward. After conducting assessments on individual wards, we created the “hot ward” tool kit: (1) 38 ward floor plans indicating ventilation setup, “green” zones, and “hot” zones; (2) a risk matrix to guide ward actions based on cycle threshold (Ct) value and duration of exposure; and (3) “hot ward” checklists. The tool kit was presented to infectious disease clinicians on the infection prevention team and senior nursing leaders for input and guidance. To ensure that these plans were practical, we conducted numerous site walks with HOD and ward nurse managers . Finally, the tool kit was shared in a meeting with key stakeholders and senior leaders. It was also uploaded to the NUH COVID-19 quick-reference intranet page for easy staff access. Results: The tool kit was used by 2 general wards when cases of confirmed COVID-19 were detected among patients. Overall, the tool kit helped HOD and nurse managers with the immediate actions required and it provides useful guidance for the infection prevention team to assess and guide decisions regarding whether a ward lockdown is necessary. Conclusions: Although the guidance was useful, from the site walk we learned that the mechanical ventilation system of some wards is shared, making it challenging to prevent cross contamination between wards because any shared ventilation between unmasked areas can be pose a risk for both patients and staff. Additional measures were instituted to mitigate this risk.


Video consulting was widely rolled out across general practice at the start of the COVID-19 pandemic. In the in-hours setting there has been a marked shift away from using the technology, but many urgent care clinicians continue to use video consulting. Little is known about the reasons behind this discrepancy.To understand how and why video is used in urgent care settings.Focus groups were held via Microsoft Teams with 11 GPs working in in- and out-of-hours settings across the UK.GPs were recruited through a convienience sampling strategy. Meetings were recorded, auto-transcribed, and checked for accuracy. A thematic analysis was performed.Urgent care GPs used video as an adjunct to the telephone in the initial assessment of patients and felt it helped direct patients to the right service first time. They were confident using video for a broad range of presenting conditions. They felt it created additional trust and rapport with patients and was useful for bringing third parties into the consultation. They felt that it allowed them to maximise resources and use shielded colleagues effectively. They emphasised the importance of one-to-one training and this was seen as vital for effective implementation within an organisation.Video consulting is useful in the urgent care setting as an adjunct to telephone consulting. It is particularly helpful in the initial triage of patients. One-to-one training is needed for effective implementation. Video consulting was introduced widely to UK general practice and urgent care settings at the start of the COVID-19 pandemic. In-hours general practice usage has declined considerably. This study highlights how urgent care GPs continue to use video consulting, finding it particularly helpful as an adjunct to the telephone in the initial assessment of patients to create rapport, reduce complaints, and to maximise resources.Urgent care services, such as NHS 111 or GP out of hours, are characterised by a primary purpose of addressing urgent medical issues. Their focus is on getting the patient the right care in an appropriate timescale to address immediate medical needs such as respiratory tract infections, paediatric fever, and abdominal pain. Doctors in such services need to quickly gain rapport and create trust so that the patient can feel confident to adhere to their recommendations. to direct the caller to the appropriate service for their needs. There are multiple possible outcomes for a call including advice from a call-handler or clinician, diversion to pharmacy, or a face-to-face appointment. Video consultation is commonly implemented as an adjunct to an initial telephone consultation and a patient often proceeds to a face-to-face appointment.UK urgent primary care services cover a large geographical footprint. To access the services, a patient calls 111 and speaks to a non-clinical call-handler who uses algorithms, such as NHS pathways,Video consulting is regularly used in the urgent care setting. This is in marked contrast to in-hours general practice. A recent article identified a range of reasons why GPs have stopped using the technology. These included the lack of additional advantage over a telephone call, technological limitations, and clinician preferences for face-to-face care.This study examined why video is more popular in the urgent care setting through interviewing GPs from both sectors in a focus group setting.A qualitative study using focus groups of UK-based GPs was conducted. All GPs met the inclusion criteria of having used video consultation in primary care since the start of the COVID-19 pandemic in March 2020 and worked in a range of settings across all four nations of the UK. Some GPs continued to use video consulting regularly, others had moved away from regular use of the technology. Both in-hours and urgent care GPs (out of hours and NHS 111) participated in focus groups held online via Microsoft Teams.A convenience sampling strategy was used for recruitment. Adverts were placed on social media sites such as GP Facebook groups and Twitter.Three focus group sessions were planned. Sixteen GPs expressed interest, and 11 participated in the three focus groups. Five of the participating GPs worked in urgent care.Potential study participants were contacted via email and sent a participant information sheet and a consent form. Participants gave informed consent to participate under Chatham House Rule.Characteristics of participating GPs are listed in  The groups were chaired by the lead author, a GP experienced in video consulting. The sessions were lively, with conflicting opinions expressed between the GPs and detailed discussion of the issues. Saturation had been reached by the end of the third focus group.Three focus groups were held via Microsoft Teams in December 2021. Groups contained between three and five GPs. An interview guide was used to ensure consistency and was formulated according to the Leung and Savithiri (2009) framework detailed in Meetings were recorded and auto-transcribed via Microsoft Teams, then manually checked for accuracy. Verification was performed through a senior qualitative researcher reviewing a call recording of one of the three focus groups.An inductive approach was taken to analysis, using grounded theory. The call recordings were listened to repeatedly in order to immerse the researcher in the data and allow nuances in tone and wording to be detected, and the voice of the GPs heard and understood. This provided an initial impression of themes that were written down. Following this immersion, the Microsoft Teams auto-transcripts were downloaded, exported to Microsoft Word, and printed. These were then manually coded using colouring pencils and themes identified and compared with the initial set of themes identified through the listening exercise. Final verification of interpretation was performed through listening back to the recordings in order to ensure all themes had been captured and that the auto-transcription was correct.The lead author conducted the analysis, concentrating on the results in relation to urgent care settings.A number of themes emerged from the focus groups. One of the most marked was the very different attitudes towards the use of video consulting by the five doctors using video in urgent care settings compared with the six working solely in traditional GP settings. Urgent care GPs were more enthusiastic about the technology and used it frequently. Themes emerging from an analysis of the comments from the urgent care GPs are shown in Box 1Video consultation was useful for the initial assessment of patients.Video allowed an additional level of rapport and trust between clinician and patient, and reduced complaints.Video consulting had value in a wide range of conditions including in identifying safeguarding issues.Video was useful for bringing others into the consultation — either to assist with physical examination or to get specialist advice for patients.Video helped maximise resources and used shielded colleagues effectively.Training was vital in order to overcome staff anxieties and get them confident using the technology.‘Not the revolution I was expecting’ . They felt that call set-up took too long, taking up time allocated for the appointment. Video consulting did not fit well within practice processes, with it often being quicker to ask a patient to attend the surgery.All of the in-hours GPs were considerably less enthusiastic than their urgent care colleagues. They felt that video consultation had value for a much more limited range of conditions, with one GP stating it was ‘Video is a bit of a faff to organise, especially if you’ve got an elderly patient, I spend so much time getting it set up.’ Even GPs who used video consulting regularly in the out-of-hours setting did not use it in their surgeries.All urgent care GPs used video consultation during the initial assessment of patients. GPs started a consultation by phone and then switched to video if they felt it would give them relevant additional information. They found it helpful in the following circumstances:First, to safely prioritise patients, identifying those who were seriously unwell and escalating their care. Several of the doctors mentioned how their 'sixth sense' came into operation on video calls:'… the video gave me the gut reaction of going: “That child doesn't look well … ” I've looked at this child and their respiratory rate [was] up and that could have been very different had I just not been going with the sort of light “Spidey-sense” [which told me] …. this isn't right … ' In contrast, in-hours GPs commented that if they were worried about a patient they would ask them to come in for an appointment:'If I’m worried about someone I always want to see them face to face.' In-hours GPs felt that video offered little additional benefit over a telephone call:'For that rapid “Do you need to go to A and E, do you need an ambulance?”, telephone is all you need, if I’m worried I’ll always bring them in.' Second, to provide justification for asking the patient to attend a face-to-face assessment. This was particularly so when the patient would have to travel long distances, common in rural areas during the out-of-hours period:'They were asking us to make parents do a 60- or 70-mile round trip, and video was really helpful in helping you decide if someone needs to be seen because you pick up “actually they look miserable, they need their vital signs done”.' 'If you’ve eyeballed them and they’re coming because you’ve seen them and you feel they need further assessment … it helps sell it to them.' In contrast, in-hours GPs, who covered much smaller geographical areas, found it more efficient to ask the patient to attend the surgery:'In a way just bringing a patient who’s 5 minutes away or right round the corner down to the practice is just quicker than trying to talk them through logging onto a system.' Third, to support decision making about which patients could safely be managed without a face-to-face appointment:'… When you get the video turned on, as a clinician you see a child who’s not in distress or struggling, and it just saved so many unnecessary contacts.' 'I find some people can sound really awful on the phone, but when you look at them on the video you can see instantly … they're actually all right and vice versa.' In-hours GPs were much less confident treating patients without seeing them face to face compared with those in urgent care:'I mean, for me, anything that I need to listen to, you know so heart sounds for example, you know … And yes, you can get away to a degree with assessing how short of breath someone is, but you can't listen to their chest.' Fourth, for directing patients to appropriate services; GPs felt that being able to 'downgrade' a patient from an emergency department (ED) to a minor injury unit offered benefits both to the patient and to the wider system.'… Things like burns, assessing the amount of area they cover, how deep they are … ' 'Often people will ring in with injuries. “I've had a fall”… and it'll be “is this broken? Is this not?” ... Often the video call helps filter what the appropriate setting is. Yeah, it might be broken, but a minor injuries [department] can cope with it.' In-hours GPs had different decisions to make; the question for them was generally not whether the patient was suitable for their services but whether the patient needed to come in to the surgery for further assessment. They therefore found less benefit in the additional information provided by the video over telephone, preferring to use photos:'I tend to find it quicker to do the photos thing, so I just send them a link and then go and deal with something else … rather than let’s get the video up, it would just take ages so we just don't have time ... ' Many of the GPs felt they gained a deeper level of personal connection with patients over video compared with telephone and that this assisted with building rapport:'It was literally just like being in a in a face-to-face consultation. It felt a lot more personal. It felt a lot easier to talk to them because they could see me. I can see them … I managed to actually just gel with them and get that rapport quite quickly.' The GP medical director of a large urgent care service reported a much lower complaint rate relating to video consultations than telephone encounters, this was attributed to a greater sense of human connection on a video rather than a telephone call:'Often you don't know those patients and they don't know you. And I do think when you add video there’s an extra connection with that individual.' In-hours GPs often already knew the patients they were treating, and did not mention the need to use video in order to increase rapport.The urgent care GPs felt video consultation was suitable for a wide range of conditions:'You can just say “pull up their T-shirt, show me their ribs”.' 'If I’m not really sure if it’s blanching [checking a rash for signs of meningitis], you can clear that up quite easily over a video if you’ve got a good connection.' 'You can do the shoulder examination for frozen shoulder quite easily on video a lot of the time, getting them to move their shoulder.' The only area urgent care GPs reported they would never use video for was for problems viewing the breasts or genitalia. This was owing to legal concerns around images:'We certainly have a rule of no intimate images, no. So things like anything that would involve genital problems or breast problems would be an absolute veto.' Urgent care GPs particularly valued video consultation in helping identify incidental safeguarding issues:'We've incidentally picked up some safeguarding issues, so we've had situations where we've ended up sort of doing referrals, either for families that clearly need a bit of extra support, or where we've had concerns.' Other conditions the urgent care GPs felt particularly benefitted from video consulting were COVID-19 cases and paediatric disorders, such as fever, where video consultation provided an extra degree of reassurance to both clinicians and parents.There was consensus among both groups of GPs that video consultation was less appropriate where there were multiple comorbidities, particularly in older people, or vague or undefined symptoms:'I would find our complex comorbid elderly patients who struggle to hear… I just find video doesn't work with them; it just gets so complicated … it’s a bit like having a family zoom. You know, it doesn't really work because everyone talks over the top of each other and no one really communicates properly. And so those sorts of things I found are just better face to face … ' Other areas the GPs generally felt were less suitable for video consultations were tonsillitis, ears, cardiac, respiratory issues (other than COVID-19), and abdominal pain. In general, the urgent care GPs were more confident than the in-hours GPs using video consultation for a wider range of issues.Two of the urgent care doctors mentioned that 'facilitated video consultation', where a relative or carer performed an enabling function, were particularly helpful as they gave clearer images and minimised technological disruption:'I had one kid where I used the mother as a sort of "avatar" effectively ... The mother was sensible, able to follow instructions. … this kid was really quite sore and was admitted and it was appendicitis … I mean, it’s like that sort of Holy Grail of all the things coming together, the history and a sensible parent and a child that was willing … ' Urgent care GPs also valued using video to add an on-call specialist into a consultation:'It was 10 miles to the nearest hospital, 20 miles to the nearest one with a surgical team and 40 miles from the vascular unit. We had a three way consultation with the vascular surgical reg and in the end we decided he … could be seen locally and in the end the diagnosis was probable DVT [deep vein thrombosis], [his limb] was cold because of venous congestion.' Video consulting allowed maximisation of scarce medical resources, particularly in the out-of-hours period, in under-doctored areas of the country, in rural areas, and at times of system pressure. Many of the doctors were uncomfortable with this, feeling that video technology was used to provide substandard care:'… they would use a lot more video rather than patients drive, you know, 30 miles and 60-mile round trip in order to get a normal appointment … That again is compromised. That’s using the video to get away with not actually having sufficient clinicians to provide a service in in a rural area.' It allowed staff to be utilised more effectively; for example, shielded doctors during the pandemic, as well as those doctors who would ideally prefer to conduct a face-to-face consultation were reported as being happier to work remotely if video was provided:'… we found it completely invaluable, especially where we had a lot of workforce that might have been either at higher risk of COVID and [who] were very concerned about still seeing patients face to face. This was a bit of a lifesaver … ' The resource that in-hours GPs focused on most was GP time. They were concerned that video calls took up appointment time, but gave little additional value over a telephone call. They commented on the awkwardness of trying to set up video consultations with patients and were alert to the challenges of both affluence and poverty as well as age. A rural GP reported patients with large houses had Wi-Fi blackspots, while those on lower incomes often had poor resolution to their phone cameras or limited data.'… our very affluent patients. Their houses are so big that they have rubbish Wi-Fi and so you know you're kind of screwed either way.' 'We had elderly folks who were fantastic because they had great experience talking to their grandchildren and WhatsApp or whatever, and we'd others who just couldn't fathom it at all.' It was recognised that doctors often needed support to familiarise themselves with the technology before they felt confident using video, and that systems needed to be user-friendly. Written instructions were inadequate to get doctors to do video calls; one-to-one training time was needed:'… especially for some of my colleagues who perhaps felt less comfortable with the IT we did notice we had to do a bit of sitting down with them and literally talking them through, actually doing a dummy call with them and saying, “look … it’s really straightforward. This is what you do. This is how it works” so that they felt more comfortable, more confident with it … just sending out written instructions didn’t always work.' In contrast to the in-hours GP setting, urgent care services had invested in the technology to make video consulting easy and integrated video into workflows. GPs who were enthusiastic about video consulting in urgent care reported they didn’t use it in-hours:'So from a practice point of view, I've literally used it five times. I still don't have dual screens. Or you know, the headsets that would work so that patients could hear what you were saying and stuff.' This study of GPs has explained why urgent care GPs find video consulting so helpful, compared with their in-hours colleagues. Their focus on getting the patient to the right service on the right timescale meant additional information gained via video at initial triage helped to identify and prioritise patients needing urgent care. Video supported decision making about which patients could be safely managed remotely, which provided extra reassurance to clinicians and patients, and where travel was needed, it allowed the patient to attend the most appropriate service for their needs. GPs believed this reduced system pressure through diverting patients from EDs to other clinical settings.Video consultation provided extra justification when asking a patient to travel long distances for further care. Video consultation allowed resources to be maximised, using home-working staff and providing care to under-doctored regions. The compromises and trade-offs of this approach were recognised by doctors.Video helped GPs to generate rapport with patients, which fed through to a lower rate of complaints.Urgent care GPs were happy to use video consultation for a wide range of conditions. They valued its ability to identify incidental safeguarding concerns. They found it particularly helpful when a carer or relative was able to help facilitate examination; for example, palpating a child’s abdomen. Video consultation allowed GPs to get rapid specialist advice for patients still at home, through adding a third party into a call.Training and infrastructure was recognised as vital, and a large part of why video consulting was effective in the urgent care setting when compared with GP practices.There are several factors inherent to the urgent care environment that make video consulting effective. The long distances that patients may have to travel and the limited capacity within out-of-hours centres and EDs mean that spending more time gaining additional information remotely via video is beneficial if it saves a face-to-face appointment, or diverts the patient to a lower-acuity setting.Patients consulting urgent care services are likely to be different to in-hours patients, in that they all have or perceive themselves to have an urgent medical need. In this patient cohort, video consultation can provide important additional information to identify seriously unwell patients or raise safeguarding concerns.In urgent care, because doctors are unknown to the patients, any additional rapport gained is significant as the consultation represents the one and only chance to establish trust. The rapid establishment of this therapeutic relationship by video allows the patient to feel reassured in a way they may not following a telephone consultation.The study sampled GPs working across the UK in a range of different primary care roles. The GPs were from a wide range of career stages. Mixed focus groups of in-hours and urgent care GPs allowed different attitudes towards video consulting in the two groups to be explored in-depth.Although saturation was reached, the convienience sampling strategy and small numbers risk not representing the full range of GP views on video consulting. Advertising on social media meant some GPs were not reached and it may have led to selection bias with more technologically confident GPs participating in the study. Lack of remuneration deterred some GPs from taking part, although payment might have influenced the findings, especially if GPs felt there was an incentive to be positive about the technology.The call recording for one of the focus groups was reviewed by a senior qualitative researcher; however, the transcripts were analysed by a single reviewer. Best practice would be for transcripts to be reviewed and coded by two different reviewers working separately and then together.The focus groups were chaired by a GP working primarily in urgent care, who regularly uses video consulting in her own clinical practice. This may have risked bias to the discussion and analysis. Attempts were made to minimise this through the GP chairing rather than contributing to the discussions, and through the involvement of colleagues in verification and analysis.A final limitation is that the study only looked at GP views. The views of patients and other primary care staff are vital to include as services are developed, but this was beyond the scope of this study. The study also did not examine patient outcomes. More quantitative study designs are needed to understand the impact of video consulting on individual patient outcomes and wider system performance. but the clinicians in this study found it particularly useful for acute illness. This is in line with other findings in pre-hospital care, where video consulting has been found to be helpful in assessing patients with stroke, burns and trauma, and mental health.A key part of urgent care services is recognising and treating acute illness. Early on in the pandemic there were concerns that acute illness was less suitable for video consulting, This study found that being able to redirect patients to a lower-acuity care setting by gaining additional information through a video call was valued by urgent care clinicians. The system benefits are unquantified but important in the context of ED pressures, as accurate ascertainment of severity allows only appropriate patients to be directed to these services. Previous studies have demonstrated that dispositions can be downgraded with the additional information provided by video, including where a patient has called 999.Another fundamental role of the telephone-based NHS 111 service is to direct patients to suitable further care on an appropriate timescale. Other studies have found video consulting is helpful for ensuring that those who need further care are directed to the right setting.In urgent care services, where clinicians are usually unfamiliar with patients, gaining a quick therapeutic rapport is vital. This study found an increase in rapport when video was used, similar to findings from other studies.The findings on video helping to identify safeguarding issues are in contrast to other research that has found remote consulting a barrier to picking up safeguarding concerns, although much of this body of work focuses on telephone rather than video consultations. and that there is a correlation between a desire for more training and the non-adoption of video consulting.The training issues highlighted by the doctors are important. Other studies have found that peer training is useful to introduce non-early adopter GPs to video consulting, One of the reasons that urgent care services are able to use video effectively is that it has been integrated into their workflows, and services have invested in dual screens and headphones.The infrastructure findings strongly echo other studies on this subject.Overall, this study adds further information about the presenting complaints where urgent care GPs feel video adds extra value, as well as about its use in conserving workforce resource and mobilising parts of the workforce that would otherwise be unavailable for patient-facing duties. It demonstrates how video can be used to bring third parties into a consultation, including to provide additional information by performing a limited examination under instruction.Video consulting is a useful adjunct to the telephone in the initial assessment of a wide range of conditions in NHS 111 and other urgent care services. By enhancing the accuracy of initial triage it allows appropriate management of patients, potentially reducing pressure on ED and ambulance services. In the context of UK emergency sector pressures, it should be more widely adopted within the NHS 111 setting, particularly at times of system pressure. Much research has focused on video consulting in the in-hours sector; however, given it appears to show more benefits for both patient and system in the urgent care setting, focus should be placed on a shift into urgent care, with potential for greater funding. Areas for further research should include patient outcomes and re-presentation rates following a video consultation, as well as a deep-dive into which presentations are most suitable for video consultation. The cost-effectiveness of video consultation and it’s impacts on equity should also be explored.Box 2For urgent care cliniciansAdding in video following initial telephone assessment gives extra information that can assist with prioritisation and disposition.If you are going to ask a patient to travel, a video consultation can help justify that decision.When a contact is completed without a face-to-face consultion, both clinician and patient can feel more confident that the right outcome has been reached if video has been used.Video can be used to bring in third parties, such as a relative to assist with examination or a specialist at another site.Listen to your gut instinct when assessing a patient via video.For in-hours GPsVideo consulting may have particular benefits when assessing acutely unwell patients.Consider using video consultations to maximise practice resources, for example, by using clinicians working remotely.Infrastructure, such as dual screens and head sets, is needed to enable video consulting to work effectively.For urgent care providersInvest in the kit to make video consulting easy, for example, dual screens and headsets.Provide one-to-one training for any clinicians reluctant to use the technology.Using video may reduce complaints and improve your ED and ambulance dispositions by allowing patients to be safely directed to a lower-acuity setting.For future researchPatient outcomes and re-presentation rates following video consultation.Which presentations to urgent care are suitable for video consultation?Cost-effectiveness of video consultation.How does video consultation affect equity and inequalities?For national bodiesRoyal College of General Practitioners: consider providing bespoke training in video consultation for urgent care settings.NHS: adopting video consulting in 111 can divert more patients down lower-acuity pathways and should be promoted and funded.


Arteriovenous malformation (AVM) is an anomaly of blood vessel formation. Numerous models have been established to understand the nature of AVM. These models have limitations in terms of the diameter of the vessels used and the impact on the circulatory system. Our goal was to establish an AVM model that does not cause prompt and significant hemodynamic and cardiac alterations but is feasible for follow-up of the AVM’s progression. Sixteen female rats were randomly divided into sham-operated and AVM groups. In the AVM group, the saphenous vein and artery were interconnected using microsurgical techniques. The animals were followed up for 12 weeks. Anastomosis patency and the structural and hemodynamic changes of the heart were monitored. The hearts and vessels were histologically analyzed. During the follow-up period, shunts remained unobstructed. Systolic, diastolic, mean arterial pressure, and heart rate values slightly and non-significantly decreased in the AVM group. Echocardiogram results indicated minor systolic function impact, with slight and insignificant changes in aortic pressure and blood velocity, and minimal left ventricular wall enlargement. The small-caliber saphenous AVM model does not cause acute hemodynamic changes. Moderate but progressive alterations and venous dilatation confirmed AVM-like features. The model seems to be suitable for studying further the progression, enlargement, or destabilization of AVM. The anastomoses were checked for patency (‘milking test’). After the hemodynamic measurements, the animals were over-anesthetized.Using an operating microscope, the histological samples—including the hearts and vessels—were dissected and fixed in 4% formalin for one week. After fixation, the samples were embedded in paraffin and sectioned (5 µm thickness). Subsequently, hematoxylin and eosin (H&E) and Van Gieson stainings were performed on the sections. The stained slides were then scanned  to analyze the morphology of the heart, aiming to identify any structural and morphological differences in the cardiomyocytes and blood vessels between the two groups.n = 8, and intact saphenous vessels, n = 12) and the AVM group .To ensure a thorough examination of the histological slides, measurements were taken in three distinct sections of the heart: basal, middle, and apex. The study involved two groups: the control group , and 100 cardiomyocytes were assessed in each section , resulting in 12 wall diameters and 300 cardiomyocytes per animal heart. These measurements were taken at various locations around the left ventricle, with the cells examined horizontally and their widths measured after zooming in.For each animal heart, the diameter of the left ventricle’s wall was measured  were conducted preoperatively and during the 3rd, 7th, and 12th postoperative weeks. Left ventricle ultrasound analysis disclosed the mass and dimensions of the anterior and posterior walls in systole and diastole. Bodyweight also increased by the 12th p.o. week in both groups as rats were aging .Concerning the posterior wall during systole, the control group demonstrated an initial decrease in thickness from 3.43 ± 0.41 mm to 3.13 ± 0.51 mm, followed by a peak at 3.57 ± 0.54 mm and a subsequent reduction to 3.24 ± 0.55 mm. The AVM group exhibited a similar pattern, with an initial decrease from 3.57 ± 0.54 mm to 3.33 ± 0.68 mm, an increase to 3.46 ± 0.67 mm, and a final decline to 3.09 ± 0.39 mm A. For thThe systolic thickness of the anterior wall in the control group decreased during the 3rd postoperative week, followed by a return to baseline values later in the study. In the AVM group, the thickness initially diminished from 3.72 ± 0.57 mm preoperatively to 3.29 ± 0.32 mm in the 7th postoperative week, then increased to 3.47 ± 0.21 mm by the 12th week D. ConcerIn the control group, the LV mass demonstrated a mild elevation from 863.15 ± 78.7 mg preoperatively to 997.8 ± 143.4 mg in the 3rd postoperative week, remaining approximately constant for the remainder of the study period. In contrast, the AVM group’s mass persisted at around 1000 ± 41.1 mg during the follow-up period B. Aortic−1 preoperatively to 231 ± 36.32 min−1 during the 3rd week, with a subsequent decrease to 200.8 ± 14.68 min−1 by the 12th week. In the AVM group, the value began at 255 ± 53.66 min−1 and gradually decreased throughout the study period to 164.2 ± 27.71 min−1  did not show significant differences as tested on the 12th week, before extermination and tissue sampling .p = 0.011 vs. preoperative condition, p = 0.025 vs. control side).The diameters (O.D.) of the vessels are summarized in p = 0.0057) compared to the control group. Similarly, an increase in the mean thickness of myocytes was observed in the AVM group (p = 0.0001)  presented analogous fluctuations after the 12-week observation period, effectively summarized using their combined average. The AVM group exhibited a significant divergence in wall thickness ( 0.0001) A.The qualitative assessment of the H&E and Van Gieson stained sections  did not The tunica intima and media layers of the saphenous vein at the site of the anastomosis significantly enlarged compared to the control saphenous veins B.The main goal of this work was to establish an AVM model that does not cause prompt and significant hemodynamic and cardiac alterations, compared to other experimental models, using arteriovenous shunts of a larger caliber. Working on rat saphenous vessels needs advanced microsurgical skills but the model may mimic a small, still asymptomatic AVM that can be studied further to investigate the factors that play a role in the progression, enlargement, and destabilization of the AVM.AVMs are complex vascular anomalies involving a feeding artery and a draining vein and have been known to manifest various symptoms, causing severe neurological complications and, in some cases, disability or death due to hemorrhage ,26. TheiThe carotid-jugular fistula (CJF) model is one of the first models created to study AVMs ,38. SpetMorgan and colleagues introduced a modified CJF model in rats involving end-to-end anastomosis of both the CCA and the EJV’s rostral ends. This model showed significant cerebral blood flow (CBF) reduction on the fistula side over 8–12 weeks. Closure of the fistula led to significant CBF elevation, causing blood–brain barrier breakdown under hypertension ,59. Rats2 reactivity upon shunt opening. This animal model’s regional hemodynamic changes effectively mimicked conditions in human brain tissues surrounding AVMs. However, this model was acute, and the procedure was somewhat complex. The extracranial and intracranial arteriovenous fistula models did not include a real AVM nidus. They primarily focused on hemodynamic and pathophysiological changes in the parenchyma adjacent to AVMs rather than on the AVM lesion.The carotid-jugular fistula model resulted in prompt hemodynamic alterations across the entire brain, predominantly in the hemisphere on the fistula side; however, it did not significantly impact regional parenchyma. To explore local cerebral hypoperfusion, an intracranial arteriovenous fistula was utilized in a dog model . Dogs weHence, there has been a necessity for an effective AVM model, one that resembles the human AVM closely in terms of anatomy, physiology, biology, and clinical features to help better comprehend AVM pathogenesis, behavior, and response to treatments.The major limitation of most of the models using arteriovenous shunts is that, after performing the connections between the arteries and veins, the new situation results in a prompt effect on hemodynamics and cardiac function. So the ‘silent’, asymptomatic AVM cannot be modeled, and the progression and slow enlargement of AVM cannot be followed up.The cardiac echography results can be explained partly by the aging of the animals, as changes were also seen in the sham-operated control animals. In the presence of slowly ‘maturing’ and enlarging AVMs, moderate but progressive changes were found, and by the 12th postoperative week, relevant histological findings were seen in the heart samples. The thickening of the shunt vessels’ wall was similar to other findings using arteriovenous shunts at different localizations and sizes ,48. For It was interesting to see that the changes were not uniform or continuously progressive in all the parameters. Adaptation mechanisms in hemodynamics and the cardiovascular system cannot be excluded, as well as the aging and growth of the animals, and possible differences in the motion (however it was not observable) of non-operated and operated legs, all may contribute to the complex changes.Limitations of this study include the relatively low case number, the effect of regular re-anesthesia, the range of the follow-up period, and the general limitation of extrapolation issues to human clinical practice. The presented rat model of non-congenital, small-caliber AVMs created on saphenous vessels does not cause acute hemodynamic changes versus other models that are based on forming various-sized artificial arteriovenous shunts at different locations. However, in certain cardiac and vascular histomorphology parameters, significant alterations were found by the end of the 12-week follow-up period. The dilatation of the shunted vessels was also developed, confirming the AVM feature. The model seems to be suitable for studying further the progression, enlargement, or destabilization of AVM in different experimental conditions, such as disturbed/altered angiogenesis and vascular remodeling.