Endoscopic Contrast-Enhanced Ultrasound and Fine-Needle Aspiration or Biopsy for the Diagnosis of Pancreatic Solid Lesions: A Systematic Review and Meta-Analysis

INTRODUCTION

Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) and endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) are currently recommended for the pathologic diagnosis of pancreatic solid lesions (PSLs). The application of contrast-enhanced endoscopic ultrasound (ECEUS) could aid the endoscopist during an FNA and/or FNB procedure. CEUS is indeed able to better differentiate the pathologic tissue from the surrounding healthy pancreatic parenchyma and to detect necrotic areas and vessels.

OBJECTIVES

Our objective was to evaluate if ECEUS could reduce the number of needle passes and side effects and increase the diagnostic efficacy of FNA and/or FNB.

METHODS

A comprehensive literature search of clinical studies was performed to explore if ECEUS-FNA or FNB could increase diagnostic accuracy and reduce the number of needle passes and adverse effects compared to standard EUS-FNA or FNB. In accordance with the study protocol, a qualitative and quantitative analysis of the evidence was planned.

RESULTS

The proportion of established diagnoses of ECEUS was 90.9% compared to 88.3% of EUS, with no statistically significant difference (p = 0.14). The diagnosis was made through a single step in 70.9% of ECEUS patients and in 65.3% of EUS patients, without statistical significance (p = 0.24). The incidence of adverse reactions was substantially comparable across both groups (p = 0.89).

CONCLUSION

ECEUS-FNA and FNB do not appear superior to standard EUS-FNA and FNB for the diagnosis of pancreatic lesions.

Neurological research in Italy from 2020 to 2023

BACKGROUND

To assess the state of neurological scientific research in Italy in the time interval 2020-2023.

METHODS

Elsevier's modular integrated platform "SciVal" was used to analyze bibliometric research products starting from scientific production data uploaded onto Scopus. We considered the research area "Neurology" in the 01/01/2020-14/06/2023 time interval, and the following variables were extracted: number of published studies, number of citations, Field-Weighted Citation Impact, and percentage of international collaborations. The contribution of Italian scientists to the neurological research was compared to that of the other nations.

RESULTS

Research identified 90,633 scientific papers in the neurological area worldwide, with a total of 472,750 citations. The products assigned to Italian groups were 6670 (53,587 citations, Field-Weighted Citation Impact 1.68, 41% international collaborations).

CONCLUSIONS

According to the present study, Italian neurological research 2020 to 2023 ranks fifth globally and third in Europe.

Dynamics of liver stiffness predicts complications in patients with HCV related cirrhosis treated with direct-acting antivirals

BACKGROUND

Direct acting antivirals(DAAs) are effective in reducing inflammatory ant fibrotic markers in patients with chronic hepatitis C virus(HCV) infection and to prevent liver-related complications. Two-dimensional shear wave elastography(2D-SWE) is an effective technique for the assessment of liver fibrosis.

AIM

To evaluate changes in liver stiffness(LS) in HCV cirrhotic patients undergoing DAA therapy and to identify non-invasive parameters that predict the occurrence of liver-related events.

METHODS

We enrolled 229 patients who received DAAs between January 2015 and October 2018. Ultrasound parameters and laboratory data were assessed before treatment and 24(T1) and 48(T2) weeks after end of treatment. Patients were followed up every 6 months to evaluate the development of HCC and other liver related complications. Multiple Cox regression analysis was used to determine parameters associated with the development of complications.

RESULTS

Model for End-stage Liver Disease(MELD) score(HR 1.16; CI 95% 1.01-1.33; p = 0.026) and a change in LS at T2(1-year Delta LS) < 20%(HR 2.98; CI 95% 1.01-8.1; p = 0.03) were independently associated with HCC risk. One-year Delta-LS <20% was independently associated with the development of ascites(HR 5.08; CI 95% 1.03 - 25.14; p = 0.04).

CONCLUSIONS

Dynamic changes of 2D-SWE-measured LS after DAA therapy may be a useful tool to identify patients who are at higher risk of liver related complications.

Drug-Induced Acute Pancreatitis in Adults: Focus on Antimicrobial and Antiviral Drugs, a Narrative Review

Acute pancreatitis (AP) is an acute inflammation of the pancreas caused by the activation of digestive enzymes in the pancreatic tissue. The main causes of AP are cholelithiasis and alcohol abuse; less commonly, it can be caused by drugs, with a prevalence of up to 5%. Causal associations between drugs and pancreatitis are largely based on case reports or case series with limited evidence. We reviewed the available data on drug-induced AP, focusing on antimicrobial drugs and antivirals, and discussed the current evidence in relation to the classification systems available in the literature. We found 51 suspected associations between antimicrobial and antiviral drugs and AP. The drugs with the most evidence of correlation are didanosine, protease inhibitors, and metronidazole. In addition, other drugs have been described in case reports demonstrating positive rechallenge. However, there are major differences between the various classifications available, where the same drug being assigned to different probability classes. It is likely that the presence in multiple case reports of an association between acute pancreatitis and a drug should serve as a basis for conducting prospective randomized controlled trials to improve the quality of the evidence.

Immunohistochemical Evaluation of the Expression of Specific Membrane Antigens in Patients with Pancreatic Ductal Adenocarcinoma

(1) Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies. The lack of validated disease biomarkers makes timely diagnosis challenging in most cases. Cell membrane and surface proteins play a crucial role in several routes of oncogenesis. The aim of this study was to evaluate the expression of six membrane antigens on PDAC (CA 19-9, mucin 1 and 4 (MUC1, MUC4), mesothelin (MSLN), Annexin A10 (ANXA10), Glypican-1 (GPC-1)) and their correlation with oncologic outcomes. (2) Methods: Immunohistochemical staining for CA 19.9, MUC1, MUC4, MSLN, ANXA10, and GPC-1 of surgical samples of 50 consecutive patients with PDAC was performed. Antigen expression for tumor, ductal, and acinar tissues was classified according to the histo-score (H-score) by two pathologists. (3) Results: Recurrence rate was 47% and 18 patients (36%) deceased (median follow-up 21.5 months). Immunostaining for CA 19-9 and MUC1 showed a significantly higher expression in the neoplastic tissue compared to non-tumor ductal and acinar tissues (p < 0.001). MUC4, MSLN, ANXA10, and GPC-1 were selectively expressed in the neoplastic tissue (p < 0.001). A CA 19-9 H-score value >270 was independently associated with a worse overall survival (p = 0.05) and disease-free survival (p = 0.05). (4) Conclusions: CA 19-9 and MUC1 are highly expressed in PDAC cells. The histological expression of CA 19-9 may predict prognosis. MUC4, MSLN, ANXA10, and GPC-1 are selectively expressed by neoplastic tissue and may represent a potential histological biomarker of disease.

Gut Microbiota and Antibiotic Treatments for the Main Non-Oncologic Hepato-Biliary-Pancreatic Disorders

The gut microbiota is a pivotal actor in the maintenance of the balance in the complex interconnections of hepato-biliary-pancreatic system. It has both metabolic and immunologic functions, with an influence on the homeostasis of the whole organism and on the pathogenesis of a wide range of diseases, from non-neoplastic ones to tumorigenesis. The continuous bidirectional metabolic communication between gut and hepato-pancreatic district, through bile ducts and portal vein, leads to a continuous interaction with translocated bacteria and their products. Chronic liver disease and pancreatic disorders can lead to reduced intestinal motility, decreased bile acid synthesis and intestinal immune dysfunction, determining a compositional and functional imbalance in gut microbiota (dysbiosis), with potentially harmful consequences on the host's health. The modulation of the gut microbiota by antibiotics represents a pioneering challenge with striking future therapeutic opportunities, even in non-infectious diseases. In this setting, antibiotics are aimed at harmonizing gut microbial function and, sometimes, composition. A more targeted and specific approach should be the goal to pursue in the future, tailoring the treatment according to the type of microbiota modulation to be achieved and using combined strategies.

"Fare male farsi male" project - Are cyberbullying and cyber victimisation associated with physical activity levels? a cross sectional study in a sample of Italian adolescents

Background

The aim of this project is to study the prevalence of cyberbullies (CB) and cybervictims (CV) and cyberbully-victims(CBV) in Italian adolescent students and a possible correlation with physical activity (PA) levels and as potential protective factor.

Methods

The Italian version of the European Cyberbullying Intervention Project Questionnaire (ECIPQ) was used for categorized cyberbullies (CB) and cybervictims (CV). Six items of the IPAQ-A Italian version were considered to measure the PA levels.

Results

2112 questionnaires were collected, with response rate of 80.5%. The sample reported 9% was CV only, 5% was CB only, and 6% was cyberbully-victims (CBV). The factors that are significant associated to the CV students were: female gender (OR=1.7; 95%CI:1.18-2.35); stay at middle school (OR=1.56; 95%CI:1.01-2.44); spent more than 2 hours on IT devices (OR=1.63; 95%CI:1.08-2.47). The variables significant associated to the CB students were: gender male (OR=0.51 95%CI:0.320.80); spent more than 2 hours on IT devices (OR=2.37; 95%CI:1.32-4.26); tobacco use (OR=2.55; 95%CI:1.63-3.98); an inverse proportion with the number of days spent in vigorous physical activities (OR=0.82; 95%CI:0.68-0.98). The CBV students were significant associated with a male gender (OR=0.58; 95%CI:0.38-0.89) and tobacco consumption (OR=2.22; 95%CI:1.46-3.37).

Conclusions

The physical activity at vigorous level seem to be related to less involvement in cyberaggression, so it is recommended that those responsible for training adolescents' favour this aspect. Research on effective prevention is insufficient and evaluation of policy tools for cyberbullying intervention is a nascent research field an any prevention or intervention program could consider this factor.

Nutrition in Acute Pancreatitis: From the Old Paradigm to the New Evidence

The nutritional management of acute pancreatitis (AP) patients has widely changed over time. The "pancreatic rest" was the cornerstone of the old paradigm, and nutritional support was not even included in AP management. Traditional management of AP was based on intestinal rest, with or without complete parenteral feeding. Recently, evidence-based data underlined the superiority of early oral or enteral feeding with significantly decreased multiple-organ failure, systemic infections, surgery need, and mortality rate. Despite the current recommendations, experts still debate the best route for enteral nutritional support and the best enteral formula. The aim of this work is to collect and analyze evidence over the nutritional aspects of AP management to investigate its impact. Moreover, the role of immunonutrition and probiotics in modulating inflammatory response and gut dysbiosis during AP was extensively studied. However, we have no significant data for their use in clinical practice. This is the first work to move beyond the mere opposition between the old and the new paradigm, including an analysis of several topics still under debate in order to provide a comprehensive overview of nutritional management of AP.

Gender differences in microRNA expression in levodopa-naive PD patients

Gender is an important factor influencing epidemiological and clinical features of Parkinson's disease (PD). We aimed to evaluate gender differences in the expression of a panel of miRNAs (miR-34a-5p, miR-146a, miR-155, miR-29a, miR-106a) possibly involved in the pathophysiology or progression of disease. Serum samples were obtained from 104 PD patients (58 men and 46 women) never treated with levodopa. We measured levels of miRNAs using quantitative PCR. Correlations between miRNA expression and clinical data were assessed using the Spearman's correlation test. We used STRING to evaluate co-expression relationship among target genes. MiR-34a-5p was significantly upregulated in PD male patients compared to PD female patients (fc: 1.62; p < 0.0001). No correlation was found with age, BMI, and disease severity, assessed by UPDRS III scale, in male and female patients. MiR-146a-5p was significantly upregulated in female as compared to male patients (fc: 3.44; p < 0.0001) and a significant correlation was also observed between disease duration and mir-146a-5p. No differences were found in the expression of miR-29a, miR-106a-5p and miR-155 between genders. Predicted target genes for miR-34a-5p and miR-146-5p and protein interactions in biological processes were reported. Our study supports the hypothesis that there are gender-specific differences in serum miRNAs expression in PD patients. Follow-up of this cohort is needed to understand if these differences may affect disease progression and response to treatment.

Diagnostic and Prognostic Role of Extracellular Vesicles in Pancreatic Cancer: Current Evidence and Future Perspectives

Pancreatic cancer is one of the most aggressive tumors, with a dismal prognosis due to poor detection rates at early stages, rapid progression, post-surgical complications, and limited effectiveness of conventional oncologic therapies. There are no consistently reliable biomarkers or imaging modalities to accurately diagnose, classify, and predict the biological behavior of this tumor. Therefore, it is imperative to develop new and improved strategies to detect pancreatic lesions in the early stages of cancerization with greater sensitivity and specificity. Extracellular vesicles, including exosome and microvesicles, are membrane-coated cellular products that are released in the outer environment. All cells produce extracellular vesicles; however, this process is enhanced by inflammation and tumorigenesis. Based on accumulating evidence, extracellular vesicles play a crucial role in pancreatic cancer progression and chemoresistance. Moreover, they may represent potential biomarkers and promising therapy targets. The aim of the present review is to review the current evidence on the role of extracellular vesicles in pancreatic cancer.

The third age: physical activity and culture over 65

The present research focuses on the delicate and complex process of senilization of the population, being one of the most important anthropological and social problems of our time. These considerations lead us to examine not so much the aging process itself, but the relationship between the third age and society, focusing on the factors that promote or inhibit well-being and the relative perceptions that emerged in the sample. In this sense, an online questionnaire was administered, by email and by telephone message, over a period of approximately 10 months starting from March 2021 until December 2021. The questionnaire included multiple choice questions that produced clear data and simple analysis, arriving at an accurate analysis (qualitative and quantitative), on the topics of interest: the role of nutrition and sport in the over 65s, not only by the subjects in question, but also the considerations and perceptions of subjects belonging to different age groups with reference to the topics of interest relating to the third age. The sample results, allow us to identify the appropriate interven-tion strategies and policies useful for eradicating the stereotype that accompanied the concept of old age until a few years ago, making it synonymous with illness, loneliness, fragility and uselessness. Finally, today, we have freed ourselves from the role of "sedentary elderly" and motor activity in the third age is increasingly widespread and relevant as can be seen from the data analysis. This research is the result of a program that has been in place for several years now to combat the hypokinesis diseases, through physical movement and particularly by examples of appropriate lifestyles. This initiative was conceived and implemented by C.I.S.C.O.D. (Comitato Italiano Sport Contro Droga) and CO.NA.P.E.F.S. (Collegio Nazionale Professori Educazione Fisica e Laureati in Scienze Motorie), two C.O.N.I. well-deserving associations, and carried out as part of a larger "Survey on nutrition and culture over 65" project, proclaimed by Sport & Salute S.p.A.

Serum uric acid in patients with ST-segment elevation myocardial infarction: An innocent bystander or leading actor?

Elevated serum uric acid (SUA) levels have been associated with several cardiovascular risk factors and the progression of coronary artery disease. In the setting of acute myocardial infarction, increasing evidence suggests that high SUA levels could be related to adverse outcomes. Interestingly elevated SUA levels have been linked to endothelial dysfunction, inflammation and oxidative stress. The aim of this review is to discuss the potential negative effects of SUA in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention, analyzing the possible underlying pathophysiological mechanisms.

P-722 Ending the anonymity of egg donors in shared donation programs could reduce the number of participants

Study question

Loss of egg donor anonymity could affect shared donation programs in Brazil?

Summary answer

Yes. Approximately 20% of the women who participated in this study would drop out of the program, especially those with higher incomes.

What is known already

The Brazilian Federal Council of Medicine seems to be increasingly flexible with regard to maintaining mandatory secrecy on the identity of donors. The resolution regarding assisted reproduction techniques, approved in 2021, concerns the possibility of donation between family members, up to fourth degree relatives. The possibility to know and have access to this identity or even the search for half-brothers can be a reality in many countries for children born through access to reproductive technology but the opinion or behaviour of this population about the presence or absence of anonymity is limited to a few studies.

Study design, size, duration

Women (n = 800) who applied for enrolment in the shared egg donation program at a private IVF clinic were invited to participate in an electronic survey developed using the online Survio® tool. The invitation to participate was sent by email from June to November 2021. 279 women (34.8%, 20-35 years) responded to the survey.

Participants/materials, setting, methods

The information was obtained through questioning and gaining information about: socioeconomic profile of the donors, their motives, ambivalence in relation to the sharing of eggs and feelings about a possible end of anonymity. Thereafter, answers given to 10 specific questions were recorded. Furthermore, a correlation analysis was performed to assess the relationship between acceptance of the end of donor anonymity and various study parameters.

Main results and the role of chance

Approximately 61% of patients would want to become egg donors for two reasons: to reduce IVF costs and to help another woman. However, significantly younger women want to be part of the egg donation program just to reduce their treatment costs (P &lt; 0.05). Approximately 71% of women do not want any contact with the child born from their eggs; 69% of them would not like to meet the recipients and 75% would not like to meet the child, even if only the recipient had become pregnant. If donors lost a child, they would not even want to meet the child who was born with their donated eggs (76%).

Most participants also responded that they would be in the program even if the anonymity was not maintained (80%). However, women with higher income would drop out of the program if donor anonymity was not maintained (56.3%) compared to women with lower income (13.5%;P &lt; 0.001).

Limitations, reasons for caution

Confounding variables related to the male partner's opinion cannot be excluded. Studies with larger samples are needed to confirm these findings.

Wider implications of the findings

A possible end to the anonymity of egg donors in Brazil would pose numerous challenges to the current practice of gamete donation. These concerns give rise to a broad discussion in society about how best to safeguard and promote the interests of donor-conceived children and protect the rights of donors.

Trial registration number

Not applicable.

P-535 Preimplantation Genetic Testing for Aneuploidy (PGT-A) for patients aged ≤ 37 years: Today, evidence-based medicine does not support its use. A meta-analysis

Study question

Do patients aged ≤37 years truly benefit from using PGT-A as an add-on to increase ongoing pregnancy rate (OPR)/live birth rate (LBR) in their first IVF/ICSI cycle?

Summary answer

The use of PGT-A is not superior to classic morphological embryonic selection to increase OPR/LBR in patients aged ≤37 years in their first IVF/ICSI cycle.

What is known already

The embryonic aneuploidies increase exponentially with advancing-maternal-age, ranging from 30-50% up to 37 years to 80% in women ≥42 years. Consequently, the use of PGT-A seems to be a useful add-on for patients with advanced-maternal-age, but not necessarily for young women undergoing their first IVF/ICSI cycle. Recent studies investigated the benefit of PGT-A, concluding that it was accompanied with lower OPR/LBR, when compared to conventional-cycles in women aged ≤37 years. However, the use of this add-on in IVF/ICSI cycles is increasing alarmingly. Furthermore, adding PGT-A in reproductive treatments is related with increased costs and limitations inherent to the test itself.

Study design, size, duration

A systematic review based on electronics searches of databases (PubMed/MEDLINE, EMBASE, Web of Science, Scopus, and Cochrane database. Keywords: PGT-A; Morphological embryonic selection; ongoing pregnancy; live birth) up to December 2021 was conducted to identify randomised controlled trials (RCTs) comparing clinical outcomes of IVF/ICSI cycles with PGT-A versus Morphological embryonic selection. The primary outcomes were ongoing pregnancy and live birth rates.

Participants/materials, setting, methods

Seven RCTs were included as targets for data extraction and meta-analysis. Three studies reported on OPR and five reported LBR of patients who underwent their first IVF/ICSI cycle. Data were combined for meta-analysis using StatsDirect statistical software. Dichotomous data were expressed as Relative Risk(RR) with a 95% confidence interval(CI). The amount of heterogeneity was evaluated using Cochran’sQ and I2. Study data were combined using a Random-effects model. P-values &lt;0.05 were considered to be statistically significant.

Main results and the role of chance

-Ongoing pregnancy rates (three trials): PGT-A group: 67.4% (485/720) versus morphological embryo selection group: 63.2% (460/728) with no statistically significant differences (RR = 1.11; 95% CI = 0.89–1.39; P=0.35)

-Live birth rate (five trials): PGT-A group: 58.9% (578/981) versus Morphological embryo selection group: 57.9% (585/1010) with no statistically significant differences (RR = 1.01; 95% CI = 0.81–1.26; P=0.91).

Table 1 shows the data.

Limitations, reasons for caution

The main limitation of this meta-analysis is the low number and heterogeneity of studies included. However, all of the included studies are randomised controlled trials, and the data were meta-analysed using Random-effects.

Wider implications of the findings

This meta-analysis brings to light a fundamental discussion currently, in which physicians and embryologists employ add-ons to improve clinical outcomes even without adequate scientific support.Medical practices are based on scientific evidence and Reproductive Medicine is not different. Therefore, at the moment, PGT-A should not be indicated for patients aged ≤37years.

Trial registration number

Not applicable

O-190 Endometrial compaction in artificial frozen-thawed embryo transfer cycles is associated with improvement in pregnancy outcomes: a meta-analysis

Study question

Does the decrease in endometrial thickness between the end of oestrogen phase and embryo transfer day (endometrial compaction) impact the pregnancy outcomes in frozen-thawed embryo transfer (FET) cycles?

Summary answer

The combined data indicated that cycles with endometrial compaction resulted in significantly higher ongoing pregnancy/live birth rate than cycles with no decrease in endometrial thickness.

What is known already

In FET cycles the monitoring of endometrial thickness was mostly concentrated at the end of the endometrium proliferation phase, while research on endometrial thickness in the luteal phase around the embryo transfer day was relatively rare. In addition, few studies have investigated the change in endometrial thickness after progesterone administration, and the conclusions are contradictory. Some studies included women who used hormone replacement therapy for endometrial preparation and showed that endometrial compaction (decreased thickness between the end of oestrogen phase and embryo transfer day) was associated with higher pregnancy rates. However, others reached different conclusions.

Study design, size, duration

A systematic review and meta-analyses was carried out to analyse the effect of endometrial compaction on FET cycle outcomes. The search strategy included online searching of databases (MEDLINE, EMBASE, The Science Citation Index, Google scholar, Cochrane Controlled Trials Register and OVID) up to December 2021. There was no language restriction and included grey literature. The following Medical Subject Headings and text words were used: frozen-thawed embryo transfer, hormonal preparation, endometrial thickness, endometrial compaction.

Participants/materials, setting, methods

Only cycles with artificial endometrial lining preparation (oestrogen-progesterone) and that compared outcomes of endometrial compaction cycles versus no endometrial compaction (no change/increased in endometrial thickness) cycles were considered. The primary outcomes were clinical pregnancy(CPR), miscarriage(MR) and ongoing pregnancy/livebirth (OPR/LBR) rates. The Breslow–Day-statistic, Q-statistic and I² (inconsistency) were used to determine the combinability of the trials. The random effects model was used for odds ratio(OR). The StatsDirect statistical software (Cheshire, UK) was used for data analysis.

Main results and the role of chance

Although endometrial compaction does not significantly affect CPR (OR:1.31[0.91-1.89],P=0.14) and MR (OR:1.18[0.87-1.59];P=0.27, it seems to be associated with a higher OPR/LBR (OR:1.54[1.12-2.13];P=0.007). Table 1 shows the data.

Limitations, reasons for caution

Some trials did not report clinical pregnancy or miscarriage rate. It could be associated with differences in the results. The retrospective nature and lack of standardisation of procedures across studies should be highlighted. Some analyses show high heterogeneity. Although statistically significant, the results in both arms are very close. 

Wider implications of the findings

The combined results support the change in endometrial thickness as an easy, low-cost, potential noninvasive marker of endometrial receptivity. However, additional trials are still needed.

Trial registration number

Not applicable

O-180 Body mass index (BMI) is not associated with ovarian response to gonadotropin during IVF/ICSI treatment: An evaluation of 4499 IVF/ICSI cycles

Study question

Is there an association between body mass index (BMI) and ovarian response in IVF/ICSI treatment?

Summary answer

BMI does not seem to be associated with the ovarian response to gonadotropin.

What is known already

Obesity is becoming an increasingly widespread health problem. Elevated BMI in patients who undergo assisted reproduction technology has been associated with higher doses of gonadotropins, higher risks of ovarian hyperstimulation syndrome, increased cancellation rates, and lower oocyte recovery compared to women with normal BMI. In addition, overweight and obese women submitted to IVF may present reduced rates of clinical pregnancy and live births and an increased miscarriage rate. However, population differences should be considered.

Study design, size, duration

This prospective cohort study included 4499 women who underwent IVF/ICSI cycles. Only one cycle per couple was considered. Inclusion criteria included normal karyotype, presence of two ovaries as observed by ultrasound examination, and no history of ovarian surgery, endometriosis, hydrosalpinx, infection, or endocrine disorders. Patients were stratified into four groups by BMI: &lt;18.5 kg/m2 (underweight); 18.5-24.9 kg/m2 (normal weight); 25-29.9 kg/m2 (overweight); and ≥30 kg/m2 (obesity).

Participants/materials, setting, methods

The BMI values were associated with age, anti-Müllerian hormone (AMH) levels, antral follicle counts (AFC), total dose of FSH and LH, number of follicles and number of retrieved oocytes (total and metaphase II) of IVF/ICSI cycles. The statistical analyses for group comparisons were performed using t test, Mann–Whitney test and the Kruskal–Wallis test.

Main results and the role of chance

No statistically significant differences were observed between BMI groups regarding age, AMH levels, AFC, dose of gonadotropin used (FSH and LH), days of stimulation, number of follicles and number of retrieved eggs (total and metaphase II). Table 1 summarizes the results.

Limitations, reasons for caution

A possible limitation is the cross-sectional nature of the data. Differences in sample size between BMI groups may have influenced the results.

Wider implications of the findings

Against common sense in the literature, the results did not reveal a relationship between BMI and the ovarian response to gonadotropins. BMI as an additional tool in the individualization of ovarian stimulation protocols should be reviewed.

Trial registration number

Not applicable.

O-157 Female body mass index (BMI) influences pregnancy outcomes: An evaluation of 4349 IVF/ICSI cycles

Study question

Does female body mass index (BMI) impair pregnancy outcomes after IVF/ICSI cycles?

Summary answer

High BMI (overweight and obesity) and low BMI (underweight) are associated with decreased clinical pregnancy and live birth rates and an increased miscarriage rate.

What is known already

Obese women undergoing treatment for infertility may face problems, such as the need for higher doses of drugs to stimulate ovulation, oocyte morphological changes, reduction in fertilization and implantation rates, and embryo quality. Compared to women of normal BMI, obese women submitted to IVF may present reduced rates of clinical pregnancy and live births and an increased miscarriage rate. Regarding the effects of low BMI, unfavourable pregnancy outcomes and infertility problems have been described, but evidence is still scarce and conflicting.

Study design, size, duration

A prospective analysis was performed of 4349 couples who underwent IVF/ICSI treatment and fresh embryo transfer. Only one cycle per couple was considered. Exclusion criteria included abnormal karyotype, uterine defects, evidence of hydrosalpinx, infections, endocrine problems, coagulation defects or thrombophilia and autoimmune defects. Couples were stratified into four groups by female BMI: &lt;18.5kg/m2 (underweight); 18.5-24.9kg/m2 (normal weight); 25-29.9kg/m2 (overweight); and ≥30kg/m2 (obesity). Clinical pregnancy, miscarriage and live birth rates were the outcomes analysed.

Participants/materials, setting, methods

Variables such as age, duration/type of infertility, previous embryo transfers, aetiologies, endometrial thickness, type of ovarian stimulation, and number/quality/development stage of embryo transferred were included as potential confounding factors. For group comparisons, the t test or chi-square test was used. Multivariate logistic regression analyses were performed to evaluate the associations between BMI and the probabilities of clinical pregnancy (CP), miscarriage and live birth (LB). Normal-weight patients were considered as the reference group.

Main results and the role of chance

Regarding confounding factors, no significant differences between BMI groups were observed.

-BMI-group comparisons showed that CP, miscarriage and LB rates significantly worsened with the increase in BMI (overweight and obesity groups). Miscarriage and LB rates also worsened with the decrease in BMI (underweight group) (Table 1).

-Compared with the normal-weight group, the overweight and obesity groups had significantly reduced rates of CP (19%/29%, respectively) and LB (27%/40%, respectively) and an increased rate of miscarriage (1.7x and 2.3x, respectively). Underweight was associated with a 49%-reduced rate of LB and a 3.0x increase in the rate of miscarriage (Table 2).

Limitations, reasons for caution

Differences in sample size between BMI groups may have influenced the results. In clinical outcomes, only fresh transfers were considered (not cumulative data). Population characteristics should be considered when interpreting the results.

Wider implications of the findings

The study suggests that higher BMI (overweight and obesity) and lower BMI (underweight) in women have a detrimental effect on ART outcomes, especially regarding the evolution of pregnancies. Problems associated with abnormal BMI should be discussed when advising couples interested in fertility treatment.

Trial registration number

Not applicable.

P371 1 YEAR OUTCOME OF BICARBON AORTIC MECHANICAL VALVE IN LOW–INR REGIMEN: RESULTS FROM SURE–AVR REGISTRY

Background

The drawback of using mechanical valve is lifelong anticoagulation use, and close monitoring is required to prevent postoperative complications, including thromboembolism and anticoagulation–related bleeding. Moderate anticoagulation after mechanical heart valve replacement has been proposed to reduce these risks. The present study aimed to evaluate the safety and feasibility of reduced oral anticoagulation after Bicarbon aortic mechanical valve replacement.

Methods

SURE–AVR is a propsective, multinational registry of patients undergoing aortic valve replacement. Between July 2018 and October 2020, among subjects undergoing AVR with Bicarbon valve in the SURE–AVR registry, 108 were assigned at discharge to low–INr regimen (international normalized ratio 1.5–2.5). Mean INr at discharge was 1.8+/–0.5 and 2.2+/–0.4 at 1 year. in–hospital and post–discharge outcomes up to 1 years were collected. The mean age was 55.5 +/–10.6 years old (range 25–82). Concomitant procedures included coronary artery bypass grafting (14.6%), mitral valve procedure (3.7%) and myectomy (1.9%). The follow–up duration averaged 1 year (361.8 +/– 258 days).

Results

No bleeding events were reported in the late follow up. The low–INR regimen did not affect the thromboembolism rates, since no stroke or transient ischemic attack were reported post–operatively at each time point. No in–hospital or late deaths were reported among the 108 subjects analyzed. In the early period (&lt;30 days), three reinterventions occurred: two because of postoperative bleeding requiring thoracotomy and one due to pericardial effusion. In the late postoperative period two reinterventions with device explant occurred (one for non–structural valve dysfunction and one for endocarditis (1.2%).

Conclusion

The results of the SURE–AVr Registry demonstrated that the proposed Lower–INR Target is safe and feasible after Bicarbon aortic mechanical valve replacement. The low–intensity anticoagulation strategy is associated with a low risk of hemorrhagic events without any increase of thromboembolic complications.

Elastography as a predictor of liver cirrhosis complications after hepatitis C virus eradication in the era of direct-acting antivirals

Chronic inflammation due to hepatitis C virus (HCV) infection leads to liver fibrosis and rearrangement of liver tissue, which is responsible for the development of portal hypertension (PH) and hepatocellular carcinoma (HCC). The advent of direct-acting antiviral drugs has revolutionized the natural history of HCV infection, providing an overall eradication rate of over 90%. Despite a significant decrease after sustained virological response (SVR), the rate of HCC and liver-related complications is not completely eliminated in patients with advanced liver disease. Although the reasons are still unclear, cirrhosis itself has a residual risk for the development of HCC and other PH-related complications. Ultrasound elastography is a recently developed non-invasive technique for the assessment of liver fibrosis. Following the achievement of SVR, liver stiffness (LS) usually decreases, as a consequence of reduced inflammation and, possibly, fibrosis. Recent studies emphasized the application of LS assessment in the management of patients with SVR in order to define the risk for developing the complications of chronic liver disease (functional decompensation, gastrointestinal bleeding, HCC) and to optimize long-term prognostic outcomes in clinical practice.

Improved gut microbiota features after the resolution of SARS‑CoV‑2 infection

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) has a tropism for the gastrointestinal tract and several studies have shown an alteration of the gut microbiota in hospitalized infected patients. However, long-term data on microbiota changes after recovery are lacking.

METHODS

We enrolled 30 patients hospitalized for SARS‑CoV‑2-related pneumonia. Their gut microbiota was analyzed within 48 h from the admission and compared with (1) that of other patients admitted for suspected bacterial pneumonia (control group) (2) that obtained from the same subject 6 months after nasopharyngeal swab negativization.

RESULTS

Gut microbiota alpha-diversity increased 6 months after the resolution of SARS-CoV-2 infection. Bacteroidetes relative abundance was higher (≈ 36.8%) in patients with SARS-CoV-2, and declined to 18.7% when SARS-CoV-2 infection resolved (p  =  0.004). Conversely, Firmicutes were prevalent (≈ 75%) in controls and in samples collected after SARS-CoV-2 infection resolution (p  =  0.001). Ruminococcaceae, Lachnospiraceae and Blautia increased after SARS-CoV-2 infection resolution, rebalancing the gut microbiota composition.

CONCLUSION

SARS-CoV-2 infection is associated with changes in the gut microbiome, which tend to be reversed in long-term period.

Metabolomics, Microbiota, and In Vivo and In Vitro Biomarkers in Type 2 Severe Asthma: A Perspective Review

Precision medicine refers to the tailoring of therapeutic strategies to the individual characteristics of each patient; thus, it could be a new approach for the management of severe asthma that considers individual variability in genes, environmental exposure, and lifestyle. Precision medicine would also assist physicians in choosing the right treatment, the best timing of administration, consequently trying to maximize drug efficacy, and, possibly, reducing adverse events. Metabolomics is the systematic study of low molecular weight (bio)chemicals in a given biological system and offers a powerful approach to biomarker discovery and elucidating disease mechanisms. In this point of view, metabolomics could play a key role in targeting precision medicine.

Biliary tract microbiota: a new kid on the block of liver diseases?

The microbiome plays a crucial role in maintaining the homeostasis of the organism. Recent evidence has provided novel insights for understanding the interaction between the microbiota and the host. However, the vast majority of such studies have analyzed the interactions taking place in the intestinal tract. The biliary tree has traditionally been considered sterile under normal conditions. However, the advent of metagenomic techniques has revealed an unexpectedly rich bacterial community in the biliary tract. Associations between specific microbiological patterns and inflammatory biliary diseases and cancer have been recently described. Hence, biliary dysbiosis may be a primary trigger in the pathogenesis of biliary diseases. In particular, recent studies have suggested that microorganisms could play a significant role in the development of gallstones, pathogenesis of autoimmune cholangiopathies and biliary carcinogenesis. Moreover, the intimate connection between the biliary tract, liver and pancreas, could reveal hidden influences on the development of diseases of these organs. Further studies are needed to deepen the comprehension of the influence of the biliary microbiota in human pathology. This knowledge could lead to the formulation of strategies for modulating the biliary microbiota in order to treat and prevent these pathological conditions.

Prevalence of elevated pulmonary artery systolic pressure in Down Syndrome young patients with and without congenital heart disease

This study examined the prevalence and distribution of elevated systolic pulmonary arterial pressure, measured by echocardiography, in young patients with down syndrome associated or not with congenital heart disease and surgical correction during childhood. Pulmonary artery systolic pressure, computed by regurgitant tricuspid flow velocity evaluation, is the most frequently used parameter for the screening of pulmonary hypertension. Down syndrome and congenital heart disease often coexist and the probability to detect elevated systolic pulmonary arterial pressure in this setting is high. However, little is known about the evaluation of pulmonary arterial pressure during growth of patients with down syndrome with or without congenital heart disease. We enrolled 47 young patients (55% of male sex; mean age: 18.4 ± 6.0 years), 40 with congenital heart disease and 7 without a cardiac defect. Systolic pulmonary arterial pressure was assessed by echocardiography. No difference was found in the population dichotomized by presence or absence of CHD. Only male sex (p=0.000), highly sensitive troponin-T (P=0.027), tricuspid annular plane systolic excursion (TAPSE, p=0.045) and sPAP (p=0.004) were elevated in surgical group. The ASD was found as, the most common structural abnormality in our patients (50%), followed by VSD (27.5%) and complex CHD (such as complete atrioventricular canal defect, CAVC = 25% and Fallot disease = 15%). Furthermore, about 45% of patients had the combined defect. Only 37.5% of patients underwent to corrective surgery during the first months of life. We observed a significantly increase of sPAP values in patients with complex CHD, such as CAVC (p=0.019) and Fallot disease (p=0.001) but, in the following multivariate analysis performed in the patients with CHD, only Fallot disease remains as independent predictors of elevated values of sPAP (p=0.022). An elevated systolic pulmonary arterial pressure may represent the key screening tool in the diagnostic assessment of suspect pulmonary arterial hypertension in high risk population with down syndrome regardless the presence of congenital heart disease.

AB0140 BAFF NEUTRALIZATION HAS JANUS-FACED EFFECT ON ATHEROSCLEROSIS ASSOCIATED WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Cardiovascular diseases (CVD) are the leading cause of death in systemic lupus erythematosus (SLE). B cells play a key role in the pathogenesis of lupus and anti-BAFF therapy has been approved in SLE. Since mature B cells also promote atherosclerosis, BAFF neutralization is expected to have an atheroprotective effect in SLE.

Objectives:

The aim of our study was to test this hypothesis using a new mouse model with a mix susceptibility to lupus and atherosclerosis that received or not an anti-BAFF treatment, and in a cohort of SLE patients in whom we monitored carotid plaques, the B cell compartment and BAFF levels.

Methods:

The effect of BAFF on atherosclerosis associated with lupus was investigated in the atherosclerosis- and lupus-proneApoe°D227Kmouse model and in a cohort of SLE patients. Mice were treated with a blocking anti-BAFF monoclonal antibody (Ab), while fed with a standard chow diet. Carotid plaque and carotid intima media thickness were assessed by ultrasound at baseline and during follow-up in SLE patients asymptomatic for CVD.

Results:

Anti-BAFF Ab inApoe°D227Kmice i/ induced a B cell depletion, ii/ efficiently treated lupus, iii/improved atherosclerosis lesions in mice that had low plasma cholesterol levels but worsened the lesions in mice with high cholesterol levels. In that case, the atheroprotective effect of the BAFF-BAFFR signaling inhibition on B cells was counterbalanced by the proatherogenic effect of the BAFF-TACI signaling inhibition on macrophages. In SLE patients, BAFF blood levels were associated with subclinical atherosclerosis. Anti-BAFF Ab treatment had a differential effect on the intima media thickness progression in SLE patients depending on the body mass index

Conclusion:

Depending on the balance between metabolic- and B cell-induced proatherogenic conditions, anti-BAFF could be respectively detrimental or beneficial on atherosclerosis development in SLE

Acknowledgments:

Guillaume Even, Yasmine Lamri, Anh-Thu Gaston,

Disclosure of Interests:

Fanny Saidoune Grant/research support from: supported by a research partnerships between the academic and GlaxoSmithKline France.

Anti-BAFF mAb (IgG1, clone 10F4B) in mice was provided by Glaxosmithkline, Nicolas Charles: None declared, Julie Chezel: None declared, Brigitte Escoubet: None declared, Thomas Papo: None declared, Antonino Nicoletti: None declared, karim sacre: None declared

Guideline review: British Society of Gastroenterology/UK-PSC guidelines for the diagnosis and management of primary sclerosing cholangitis

New British Society of Gastroenterology/UK-PSC guidelines have recently discussed the current state-of-the-art on primary sclerosing cholangitis and outlined key elements for the management of this disease. The current lack of effective pharmacological treatments to prevent progression of liver fibrosis to cirrhosis limits our ability to modify the natural history of the disease. However, a personalised approach and structured follow-up could allow earlier diagnosis and management of complications and favour access to liver transplantation, which remains the only available treatment. Our commentary overviews the updates and summarises the key recommendations of the recent guidelines for the management of primary sclerosing cholangitis.

Gut microbiota and aging

The hypothesis of an important role of gut microbiota in maintaining physiological state into the gastrointestinal (GI) system is supported by qualitative and quantitative alteration of the intestinal flora in a number of physiological and pathological condition as shown in several studies. The evidence of the inflammatory state alteration, highlighted in neurodegenerative diseases such as Parkinson's and Alzheimer's strongly recalls the microbiota disturbance, highly suggesting a link between the gastrointestinal system and cognitive functions. Given this perspective, looking at the mutual influence between microbiota products, inflammation mediators and immune system, the modulation of gut microbiota may help to facilitate a physiological and non-pathological aging process and, perhaps, to contrast the progression of degenerating mechanisms. Some studies have already characterized gut microbiota in elderly, with promising results. Future studies should be designed to better understand the correlation between the gut microbiota, the ageing process and degenerative diseases typical of the elderly.

P4618Lack of CD31 results in microvascular plugging and increased infarction size in an experimental model of myocardial ischemia-reperfusion injury

Background

The success of coronary recanalization therapy for the treatment of myocardial infarction can be hampered by microvascular plugging which prevents effective reperfusion of the ischemic tissue. Due to its constitutive expression in platelets, leukocytes, and endothelial cells and its peculiar tyrosine phosphatase cell detaching signaling properties, the trans-homophilic CD31 receptor may be important to modulate platelet and leukocyte aggregation in the microvasculature.

Objective

To investigate the impact of CD31 genetic deficiency on the infarct size, peri-infarction microvascular plugging and macrophage phenotype in a mouse model of heart ischemia/reperfusion.

Methods

Cardiac ischemia was induced in WT and CD31 KO mice (n=30, 15 females and 15 males in each group) by surgical ligation of the left anterior descending coronary artery (LAD) for 45 minutes followed by reperfusion for 72 hours. The area at risk (AAR) and necrotic zone (NZ) were assessed using ImageJ software on three consecutive 1 mm thick slices of the left ventricle (LV) by a combination of a blue dye and 2,3,5-triphenyltetrazolium chloride staining. Parallel sets of experiments served to evaluate by both fluorescence microscopy and cytometry the presence of microvascular plugs and leukocyte phenotype in the infarction area as compared to the peri-necrotic myocardium.

Results

The AAR was similar in WT and CD31 KO mice (41,7±3,5 vs 37±2,9% of LV, NS) whereas the size of myocardial infarction was significantly greater in CD31 KO as compared to WT mice (23,4±2 vs 17,8±1,7% of LV, p<0,05). Immunofluorescent microscopy showed a dramatic increase in microvascular platelets-rich plugs around the infarction in CD31 KO mice (Figure), confirmed by cytometry analysis (9749±573 vs 5976±376 platelet-leukocyte aggregates/mg of tissue, p<0.001). Furthermore, we found that the ratio between M1 and M2 type macrophages in the peri-infarction myocardium was significantly increased in CD31 KO mice (0,7±0.07) as compared to WT mice (0,4±0.06, p<0,01).

Conclusions

Our data suggest that CD31 is important for reducing the size of necrosis following coronary recanalization procedures by preventing the no-reflow phenomenon due to microvascular plugging and by promoting a reparative phenotype of peri-infarction macrophages.

Acknowledgement/Funding

Institut Servier - ANRT (CIFRE doctoral grant)

Intestinal permeability in the pathogenesis of liver damage: From non-alcoholic fatty liver disease to liver transplantation

The intimate connection and the strict mutual cooperation between the gut and the liver realizes a functional entity called gut-liver axis. The integrity of intestinal barrier is crucial for the maintenance of liver homeostasis. In this mutual relationship, the liver acts as a second firewall towards potentially harmful substances translocated from the gut, and is, in turn, is implicated in the regulation of the barrier. Increasing evidence has highlighted the relevance of increased intestinal permeability and consequent bacterial translocation in the development of liver damage. In particular, in patients with non-alcoholic fatty liver disease recent hypotheses are considering intestinal permeability impairment, diet and gut dysbiosis as the primary pathogenic trigger. In advanced liver disease, intestinal permeability is enhanced by portal hypertension. The clinical consequence is an increased bacterial translocation that further worsens liver damage. Furthermore, this pathogenic mechanism is implicated in most of liver cirrhosis complications, such as spontaneous bacterial peritonitis, hepatorenal syndrome, portal vein thrombosis, hepatic encephalopathy, and hepatocellular carcinoma. After liver transplantation, the decrease in portal pressure should determine beneficial effects on the gut-liver axis, although are incompletely understood data on the modifications of the intestinal permeability and gut microbiota composition are still lacking. How the modulation of the intestinal permeability could prevent the initiation and progression of liver disease is still an uncovered area, which deserves further attention.

Hyperkinetic movement disorders in congenital disorders of glycosylation

BACKGROUND AND PURPOSE

Congenital disorders of glycosylation (CDG) represent an increasing number of rare inherited metabolic diseases associated with abnormal glycan metabolism and disease onset in infancy or early childhood. Most CDG are multisystemic diseases mainly affecting the central nervous system. The aim of the current study was to investigate hyperkinetic movement disorders in patients affected by CDG and to characterize phenomenology based on CDG subtypes.

METHODS

Subjects were identified from a cohort of patients with CDG who were referred to the University Hospital of Catania, Italy. Patients were evaluated by neurologists with expertise in movement disorders and videotaped using a standardized protocol.

RESULTS

A variety of hyperkinetic movement disorders was detected in eight unrelated CDG patients. Involuntary movements were generally observed early in childhood, maintaining a clinical stability over time. Distribution ranged from a generalized, especially in younger subjects, to a segmental/multifocal involvement. In patients with phosphomannomutase 2 CDG, the principal movement disorders included dystonia and choreo-athetosis. In patients affected by other CDG types, the movement disorders ranged from pure generalized chorea to mixed movement disorders including dystonia and complex stereotypies.

CONCLUSIONS

Hyperkinetic movement disorder is a key clinical feature in patients with CDG. CDG should be considered in the differential diagnosis of childhood-onset dyskinesia, especially when associated with ataxia, developmental delay, intellectual disability, autism or seizure disorder.

Diagnostic and therapeutic potential of the gut microbiota in patients with early hepatocellular carcinoma

The gut microbiota is involved in the maintenance of the homeostasis of the human body and its alterations are associated with the development of different pathological conditions. The liver is the organ most exposed to the influence of the gut microbiota, and recently important connections between the intestinal flora and hepatocellular carcinoma (HCC) have been described. In fact, HCC is commonly associated with liver cirrhosis and develops in a microenvironment where inflammation, immunological alterations, and cellular aberrations are dramatically evident. Prevention and diagnosis in the earliest stages are still the most effective weapons in fighting this tumor. Animal models show that the gut microbiota can be involved in the promotion and progression of HCC directly or through different pathogenic mechanisms. Recent data in humans have confirmed these preclinical findings, shedding new light on HCC pathogenesis. Limitations due to the different experimental design, the ethnic and hepatological setting make it difficult to compare the results and draw definitive conclusions, but these studies lay the foundations for a pathogenetic redefinition of HCC. Therefore, it is evident that the characterization of the gut microbiota and its modulation can have an enormous diagnostic, preventive, and therapeutic potential, especially in patients with early stage HCC.

Blink reflex recovery cycle to differentiate progressive supranuclear palsy from corticobasal syndrome

BACKGROUND AND PURPOSE

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) may share similar clinical findings and tests to distinguish between the two disorders could be useful. We evaluated the blink reflex and R2 blink reflex recovery cycle (R2BRRC), determining diagnostic sensitivity, specificity and positive and negative predictive value of R2BRRC in differentiating patients with PSP from those with CBS.

METHODS

This was a prospective data collection study investigating blink reflex and R2BRRC at interstimulus intervals (ISIs) of 100, 150, 200, 300, 400, 500 and 750 ms in 12 patients with PSP, eight patients with CBS and 10 controls.

RESULTS

Patients with PSP have earlier recruitment of R2BRRC as compared with patients with CBS (ISI: 100 ms, P = 0.002; 150 ms, P < 0.001; 200 ms, P < 0.001; 300 ms, P = 0.02) and controls (ISI: 100 ms, P < 0.001; 150 ms, P < 0.001; 200 ms, P < 0.001; 300 ms, P = 0.004). The presence of an early recovery of the R2 differentiated PSP from CBS with a specificity and sensitivity of 87.5% and 91.7%, respectively.

CONCLUSIONS

The R2BRRC curve might be considered to be a useful tool in differentiating patients with PSP from those with CBS.

Thymic function is a major determinant of onset of antibody-mediated rejection in heart transplantation

Thymic function decreases progressively with age but may be boosted in certain circumstances. We questioned whether heart transplantation was such a situation and whether thymic function was related to the onset of rejection. Twenty-eight antithymocyte globulin-treated heart transplant recipients were included. Patients diagnosed for an antibody-mediated rejection on endomyocardial biopsy had a higher proportion of circulating recent thymic emigrant CD4+ T cells and T cell receptor excision circle levels than other transplanted subjects. Thymus volume and density, assessed by computed tomography in a subset of patients, was also higher in patients experiencing antibody-mediated rejection. We demonstrate that thymic function is a major determinant of onset of antibody-mediated rejection and question whether thymectomy could be a prophylactic strategy to prevent alloimmune humoral responses.

A Physical Model of the Human Systemic Arterial Tree

A physical model of the human arterial tree has been developed to be used in a computer controlled mock circulatory system (MCS). Its aim is to represent systemic arterial tree properties and extend the capacity of the MCS to intraortic balloon pump (IABP) testing. The main problem was to model the aorta simply and to accurately reproduce aortic impedance and related flow and pressure waveforms at different sections. The model is composed of eight segments; lumped parameter models are used for its peripheral loads.

After the numerical simulation, the physical model was reproduced as a silicon rubber tapered tube. This rubber was chosen for its stability over time and the acceptable behaviour of its Young's modulus (Ey =22.23 gf·mm–2) with different loads and in comparison with data from the literature (Ey ≈ 20.4 gf·mm–2). The properties of each segment of the aorta were defined in terms of compliance, resistance and inertance as a function of length, radius and thickness. The variable thickness was obtained using positive and negative molds. Total static compliance of the aorta model is about 1.125·10–3 g–1cm4·sec2 (1.5 cm3·mmHg–1). Measurements were performed both on numerical and physical models (in open and closed loop configuration). Data reported show pressure and flow waveforms along with input impedance modulus and phase. The results are in good agreement with data from the literature.