Epidemiological insights into paratuberculosis in camels in Saudi Arabia: Bayesian estimation of true prevalence and identification of risk factors

Paratuberculosis, caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a significant concern in the camel population of Saudi Arabia. This study aimed to provide epidemiological insights into the disease by estimating the true prevalence in camels in the Eastern Province and Riyadh, using a Bayesian estimation framework, and exploring the associated risk factors through a frequentist approach. A total of 1200 camel blood samples were collected and analyzed using an indirect ELISA method. The true herd-level prevalence was estimated at 0.7 (95% probability interval: 0.57 to 0.81), and the mean expected true animal-level prevalence was 0.17 (0.14 to 0.20). Risk factors associated with Map seropositivity were identified, including sex, breed, raising system, and production type. Females, single breed camels, and nomadic raising systems were found to have lower odds of seropositivity, while camels used for racing and show had significantly higher odds. The study's Bayesian approach, adjusting for the imperfect accuracy of MAP tests, provides a nuanced understanding of the disease's prevalence in the region. The integration of true prevalence estimates with risk factor analysis offers a comprehensive framework that can guide future policies and strategies in the fight against paratuberculosis in Saudi Arabia. The findings emphasize the importance of targeted control measures, underscoring the urgent need for interventions in Saudi Arabia's camel population. By understanding the true disease prevalence and its associated risk factors, we can enhance disease management strategies, offering valuable insights for future control and eradication efforts in the region.

Phosphine interacting with argon: potential energy surface and line widths of PH3 perturbed by Ar

The phosphine-Ar (PH₃-Ar) van der Waals complex's three-dimensional potential energy surface (3D-PES) was mapped along the intermonomer coordinates using the explicitly correlated Coupled Clusters approach. An analytical expansion of this 3D-PES is deduced. The complex characteristics of the intermolecular interactions between PH₃ and Ar, which are at the origin of the pressure broadening of the PH₃ rovibrational lines, are accurately described by this 3D-PES. Afterwards, the broadening of the phosphine lines perturbed by Ar at room temperature is computed using this 3D-PES. To be able to incorporate this 3D-PES into our collisional broadening computation software, we first modified it with a new "fractional" function. Then, we used the semiclassical Modified Robert and Bonamy model improved by the so-called notion of exact trajectory. For various branches of the ν₂ and ν₄ PH₃ rovibrational bands, room temperature data are provided. Our data agree with the experimental measurements. The precise estimation of PH₃ and Ar abundances in planetary atmosphere spectra should benefit greatly from the data provided here.

Improving the detection of new lesions in multiple sclerosis with a cascaded 3D fully convolutional neural network approach

Longitudinal magnetic resonance imaging (MRI) has an important role in multiple sclerosis (MS) diagnosis and follow-up. Specifically, the presence of new lesions on brain MRI scans is considered a robust predictive biomarker for the disease progression. New lesions are a high-impact prognostic factor to predict evolution to MS or risk of disability accumulation over time. However, the detection of this disease activity is performed visually by comparing the follow-up and baseline scans. Due to the presence of small lesions, misregistration, and high inter-/intra-observer variability, this detection of new lesions is prone to errors. In this direction, one of the last Medical Image Computing and Computer Assisted Intervention (MICCAI) challenges was dealing with this automatic new lesion quantification. The MSSEG-2: MS new lesions segmentation challenge offers an evaluation framework for this new lesion segmentation task with a large database (100 patients, each with two-time points) compiled from the OFSEP (Observatoire français de la sclérose en plaques) cohort, the French MS registry, including 3D T2-w fluid-attenuated inversion recovery (T2-FLAIR) images from different centers and scanners. Apart from a change in centers, MRI scanners, and acquisition protocols, there are more challenges that hinder the automated detection process of new lesions such as the need for large annotated datasets, which may be not easily available, or the fact that new lesions are small areas producing a class imbalance problem that could bias trained models toward the non-lesion class. In this article, we present a novel automated method for new lesion detection of MS patient images. Our approach is based on a cascade of two 3D patch-wise fully convolutional neural networks (FCNNs). The first FCNN is trained to be more sensitive revealing possible candidate new lesion voxels, while the second FCNN is trained to reduce the number of misclassified voxels coming from the first network. 3D T2-FLAIR images from the two-time points were pre-processed and linearly co-registered. Afterward, a fully CNN, where its inputs were only the baseline and follow-up images, was trained to detect new MS lesions. Our approach obtained a mean segmentation dice similarity coefficient of 0.42 with a detection F1-score of 0.5. Compared to the challenge participants, we obtained one of the highest precision scores (PPVL = 0.52), the best PPVL rate (0.53), and a lesion detection sensitivity (SensL of 0.53).

Evaluating the use of synthetic T1-w images in new T2 lesion detection in multiple sclerosis

The assessment of disease activity using serial brain MRI scans is one of the most valuable strategies for monitoring treatment response in patients with multiple sclerosis (MS) receiving disease-modifying treatments. Recently, several deep learning approaches have been proposed to improve this analysis, obtaining a good trade-off between sensitivity and specificity, especially when using T1-w and T2-FLAIR images as inputs. However, the need to acquire two different types of images is time-consuming, costly and not always available in clinical practice. In this paper, we investigate an approach to generate synthetic T1-w images from T2-FLAIR images and subsequently analyse the impact of using original and synthetic T1-w images on the performance of a state-of-the-art approach for longitudinal MS lesion detection. We evaluate our approach on a dataset containing 136 images from MS patients, and 73 images with lesion activity (the appearance of new T2 lesions in follow-up scans). To evaluate the synthesis of the images, we analyse the structural similarity index metric and the median absolute error and obtain consistent results. To study the impact of synthetic T1-w images, we evaluate the performance of the new lesion detection approach when using (1) both T2-FLAIR and T1-w original images, (2) only T2-FLAIR images, and (3) both T2-FLAIR and synthetic T1-w images. Sensitivities of 0.75, 0.63, and 0.81, respectively, were obtained at the same false-positive rate (0.14) for all experiments. In addition, we also present the results obtained when using the data from the international MSSEG-2 challenge, showing also an improvement when including synthetic T1-w images. In conclusion, we show that the use of synthetic images can support the lack of data or even be used instead of the original image to homogenize the contrast of the different acquisitions in new T2 lesions detection algorithms.

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Contemporary trends can be revealed in an enquiry of presentations at a surgical symposium

Aims

Ascertain whether a demographic analysis of the archives of an annual national meeting head and neck section could reflect contemporary issues in our specialty and compare the results with available analysis from other ORL-HNS meetings.

Materials and methods

A review of all accepted abstracts of Sylvester O’Halloran Symposium—H&N section, from 2005 to 2020.

Results

ORL-HNS was responsible for 77% of the accepted abstracts. Presentations on H&N Malignancy were predominantly from ORL-HNS (84%), while Thyroid presentations were divided with General Surgery (45%). Medical students have appeared in recent years and produced 4% of papers at the last meeting while more junior presenters are participating with an increasing female preponderance (ranging from 7 to 53%). The overall publication rate was 27%, where male authors had a rate of 28% and females 22%. Similar papers published subsequent to the relevant meeting were identified from other institutions in 40% of presentations.

Conclusion

This review of presentations at a surgical meeting provides an insight into contemporary issues involving our specialty and lays down markers or challenges for organisers and presenters alike. Presentations on H&N Malignancy have become almost exclusively ORL-HNS, while Thyroid presentations are becoming more valorised to General Surgery and Facial Plastics with our colleagues in Plastic Surgery and Maxillofacial. Our publication rate of 27% is similar to other ORL-HNS meetings. Approximately 10% are published over 5 years after the meeting but presenters should endeavour to publish earlier as others may usurp publication in up to 40% of presentations.

Cardiac Myxomas Resembling Malignant Neoplasia: Incidentally Diagnosed vs. Cerebral Embolized Myxomas

Background: Cardiac myxomas (CM) are the most common primary cardiac tumors in adults. They are usually benign; however, malignant changes are known to occur but are extremely rare. Embolization is a common complication of cardiac myxomas and can cause neurological deficits before their surgical removal. The current study analyzed the outcomes after operative myxoma excision in patients, with and without cerebral embolic events prior to excision. Methods: All 66 consecutive patients who underwent a surgical excision of CM between 2005 and 2019 at our department were analyzed retrospectively. Patients with (n = 14) and without (n = 52) preoperative strokes caused by cerebral tumor embolization were compared. Results: The mean age was 58.4 ± 12.7 years in the stroke group (SG) and 62.8 ± 11.7 years in the non-stroke group (N-SG) (p = 0.226). Gender (35.7% vs. 61.5% female; p = 0.084) did not differ significantly, and comorbidities were comparable in both groups. The left hemisphere in the territory of the middle cerebral artery was affected by preoperative cerebral infarction most commonly (28.6%). The time from diagnosis to cardiac surgery procedure was 7 (3−24) days in the SG and 23 (5−55) days in the N-SG (p = 0.120). Cardiac myxomas were localized in the left atrium in both groups more frequently (SG: 92.9% vs. N-SG: 78.8%; p = 0.436). In the SG, 57.1% of CM had a non-solid surface, were localized in the left heart, and had a pedunculated attachment away from the fossa ovalis. In the N-SG, 92.3% of CM did not meet all these criteria (p < 0.001). The maximal diameters of CM were comparable (SG: 3.4 ± 1.5 cm vs. N-SG: 3.8 ± 2.1 cm; p = 0.538). The operation times (192.5 (139.3−244.5) min vs. 215.5 (184.5−273.3) min; p = 0.046) and the cross-clamp times (54.5 (33.3−86.5) min vs. 78.5 (55−106.8) min; p = 0.035) were significantly shorter in the SG. Only in the N-SG were reconstructions of the endocardium with bovine pericardium required after resection (51.9% vs 0%; p < 0.001). In the N-SG, CM were explored via the right atrium more often (57.7% vs. 14.3%; p = 0.007). Patients in the N-SG required significantly shorter ICU care after surgery (p = 0.020). Other postoperative courses did not differ significantly. After tumor removal, 1.9% of the N-SG suffered their first stroke and 14.3% of the SG had a cerebral re-infarction (p = 0.111). The 30-day mortality rates were 1.9% in the N-SG and 7.1% in the SG (p = 0.382). In one case in the N-SG, a tumor recurrence was diagnosed. The Kaplan−Meiercurves showed a significantly better long-term prognosis for patients in the N-SG (p = 0.043). Conclusions: After the surgical removal of CM, the outcome is compromised if preoperative cerebral embolization occurs. Surgical treatment is therefore indicated as soon as possible, especially when CM have a non-solid surface, are localized in the left heart, and have a pedunculated attachment away from the fossa ovalis.

Surgery after Failed Transcatheter Aortic Valve Implantation: Indications and Outcomes of a Concerning Condition

OBJECTIVES

The number of transcatheter aortic valve implantations (TAVI) has increased enormously in recent decades. Transcatheter valve prosthesis failure and the requirement of conventional surgical replacement are expected to attract more focus in the near future. Indeed, given the scarcity of research in this field, the next decade will likely represent the beginning of a period of meaningful exploration of the degenerative changes that occur with transcatheter valves. The current study represents-through a series of consecutive cases-one of the first analyses of the underlying causes of TAVI failure, i.e., degenerative, functional and infective, followed by surgical aortic valve replacement (SAVR) and postoperative outcome.

METHODS

Between October 2008 and March 2021, 2098 TAVI procedures, including 1423 with transfemoral, 309 with transapical, and 366 with transaortic access, were performed in our institution. Among these, 0.5% (number(n) = 11) required acute SAVR (n = 6) within 7 days (n = 3) or later (n = 2), and were included in the study.

RESULTS

Valve stent dislocation was the most common cause of replacement (83%). Causes of replacement within 7 days after TAVI were multifactorial. In the later course, endocarditis was the sole indication for SAVR after TAVI. TAVI with transapical or transaortal approach had a higher EuroSCORE II (10.9 (7.2-35.3) vs. 3.5 (1.8-7.8)). Their 30-day mortality after surgical conversion was higher (67% vs. 20%), when compared to those who underwent a transfemoral procedure. The longest documented survival beyond 30 days was 58 months.

CONCLUSIONS

The causes of SAVR after TAVI failure are multifactorial, and include biological, physical and infectious factors. An acceptable midterm prognosis may be expected in patients with physical causes when dislocation of the catheter prosthesis is observed; in such cases, emergency conversion is required. Conversion due to infection, as in cases of endocarditis, had the worst outcome. Prognosis after conversion due to degeneration is still problematic, due to a lack of autopsies and the recent history of prosthetic implantations.

No IV hydration vs IV hydration in prevention of contrast-induced nephropathy: meta-analysis of randomized controlled trials

Background

Iodinated contrast is commonly utilized in modern medicine. However, it does not come free of risks. Incidence of contrast induced nephropathy is estimated to be 1% to 6% and can be as high as 50% in patients at high risk. IV hydration is routinely used to prevent Contrast-Induced Nephropathy (CIN). Recent randomized controlled trials (RCTs) suggested that no hydration is not inferior to hydration in prevention of CIN.

Objective

To evaluate the risk of forgoing IV hydration in patients undergoing procedures utilizing iodinated IV contrast.

Methods

We searched MEDLINE, COCHRANE, EMBASE databases for RCTs comparing no IV hydration to IV hydration in patients undergoing procedures utilizing IV iodinated contrast such as CT contrast and coronary interventions. Studies comparing any preventive measure to IV hydration were excluded. 6 RCTs were extracted that match our search criteria (1–6). 3 RCTs included patients undergoing percutaneous coronary intervention and 3 RCTs included patients with CKD stage III undergoing contrast CT. Outcome evaluated was the risk of Contrast-Induced Nephropathy in no IV hydration group compared to IV hydration group. Analysis was conducted initially using all 6 RCTs. Additional analysis was conducted using studies limited to contrast CT in patients with stage III chronic kidney disease (CKD) (3,5,6).

Results

A total of 1938 patients (972 in no IV hydration group vs 966 in IV hydration group) were analyzed from 6 RCTs. CIN occurred in 111 (11.4%) in no IV hydration group and in 62 (6.4%) in IV hydration group. Relative risk of CIN in no IV hydration group was 1.75 [95% CI 1.31–2.33, P=0.0001, I2=0%] (Figure 1).

In our analysis utilizing trials limited to contrast CT in patients with CKD stage III, a total of 1261 patients (634 in no hydration group vs 627 in IV hydration group) were analyzed from 3 RCTs. 2 trials utilized IV sodium bicarbonate and 1 used IV normal saline in IV hydration arm. CIN occurred in 21 (3.3%) who did not receive prophylactic IV hydration and in 17 (2.7%) received IV hydration. There was no increased risk of CIN in patients who did not receive IV hydration in patients with CKD stage III underwent contrast CT. Relative risk was 1.24 [95% CI 0.66–2.32, P=0.51, I2=0%] (Figure 2).

Conclusion

In patients with CKD stage III undergoing IV contrast CT scans, withholding IV hydration is not associated with increased risk of CIN compared to IV hydration. Nevertheless, this conclusion does not apply to patients undergoing coronary intervention. The difference in outcome could be explained by the population undergoing coronary interventions which is typically higher risk, and the dose of contrast which is typically higher in coronary interventions than in contrast CT.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Restrictive vs liberal blood transfusion strategy in patients with symptomatic coronary artery disease: meta-analysis from randomized controlled trials

Background

Anemia is common in patients with symptomatic coronary artery disease. Observational studies investigated blood transfusion threshold in symptomatic coronary artery disease but results were conflicting. Meta-analyses evaluating transfusion threshold utilized data mainly from observational trials but no meta-analysis, to our knowledge, used data solely from randomized clinical trials.

Objective

The goal of our study is to evaluate efficacy and safety outcomes in anemic patients presenting with symptomatic coronary artery disease using pooled data from randomized clinical trials.

Methods

We queried Medline, Embase and Cochrane data bases for randomized clinical trials comparing restrictive blood transfusion (defined as transfusion when hemoglobin is less than 8 gm/dl) vs liberal blood transfusion (transfusion when hemoglobin is less than 10 gm/dl) in patients presenting with symptomatic artery disease or acute coronary syndrome. We identified 3 randomized controlled trials; MINT, CRIT and REALITY trials. Data were pooled from 3 trials. Efficacy outcomes evaluated were all-cause mortality and New or recurrent myocardial infarction. Safety outcomes were congestive heart failure at 30-day follow up.

Results

A total of 820 patients were included in our meta-analysis; 420 patients in restrictive blood transfusion protocol and 400 in liberal blood transfusion protocol

There was no difference between two groups at 30-day follow up in all identified outcomes (all-cause mortality, new or recurrent myocardial infarction, and Congestive heart failure).

55 patients died (22/420 in restrictive group and 33/400 in liberal group). Risk ratio of all-cause mortality in restrictive group was 0.63 [95% CI (0.38–1.07), P=0.09, I2=30%].

15/420 in restrictive group and 16/400 in liberal group had new or recurrent myocardial infarction. Risk ratio of myocardial infarction in restrictive group was 0.91 [95% CI (0.46–1.80), P=0.78, I2=0%].

20/420 patients in restrictive group and 24/400 in liberal group had congestive heart failure with risk ratio of 0.80 [95% CI (0.19–3.37), P=0.30, I2=76%] in restrictive group.

Conclusion

Our meta-analysis showed similar outcomes between restrictive and liberal transfusion policies in patients presenting with symptomatic coronary artery disease of acute myocardial infarction. Our findings are consistent with available data about restricting transfusion in general population. Restricting blood transfusion might be cost-effective. Further studies are warranted to evaluate long term safety and efficacy of such approach.

Funding Acknowledgement

Type of funding sources: None.

Polypill and its association with cardiovascular morbidity and mortality: meta-analysis from randomized controlled trials

Background

Polypill or fixed dose combination pill (containing antihypertensive and cholesterol lowering agents) has shown, in multiple studies, to increase adherence and improve blood pressure and cholesterol measurements in at risk underprivileged populations. However, its long term effect on mortality, cardiovascular and cerebrovascular outcomes in high risk groups is not well-established.

Objective

To assess mortality, cardiovascular and cerebrovascular outcomes in higher risk patients using polypill containing fixed dose of Aspirin, antihypertensive drugs and Statin compared to standard care or placebo.

Methods

We queried MEDLINE, COCHRANE, and EMBASE databases for randomized controlled trials (RCTs) comparing polypill containing Aspirin, Statin and at least 2 antihypertensive medications, to standard care or placebo in patients with increased risk of cardiovascular diseases. We looked for trials including data about mortality, coronary and cerebrovascular events. We excluded trials that did not include outcomes of interest. 5 RCTs matching our criteria were included in our meta-analysis; UMPIRE 2013, IMPACT 2014, Kanyini GAP 2015, PolyIran 2019, and TIPS-3 2021.

Results

12828 patients (6419 in polypill vs 6409 in standard care/placebo groups) with known all-cause mortality, coronary events and cerebrovascular events outcomes were analyzed from 5 RCTs. For cardiovascular mortality outcome, 12205 patients (6108 in polypill vs 6097 in standard care/placebo groups) were analyzed from 4 RCTs since 1 RCT lacked data about cardiovascular mortality outcome. There was no difference between both groups in all four outcomes.

Risk ratio of all-cause morality and cardiovascular mortality in polypill group was 0.89 [95% CI 0.76–1.03, P=0.11, I2=0%] and 0.77 [95% CI 0.48–1.26, P=0.31, I2=59%] respectively (Figure 1).

Risk ratio of coronary events in polypill group was 0.88 [95% CI 0.64–1.20, P=0.41, I2=40%]. Relative risk of cerebrovascular events was 0.73 [95% CI 0.36–1.48, P=0.38, I2=63%] (Figure 2).

Conclusion

Polypill, despite being a practical solution to non-adherence in at risk underprivileged groups, does not improve mortality or major cardiovascular or cerebrovascular outcomes compared to standard care or placebo. Further efforts need to be made towards aggressive preventative measures and encouraging adherence to medications in groups at risk.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Calculated Plasma Volume Status Is Associated with Adverse Outcomes in Patients Undergoing Transcatheter Aortic Valve Implantation

Background: Calculated plasma volume status (PVS) reflects volume overload based on the deviation of the estimated plasma volume (ePV) from the ideal plasma volume (iPV). Calculated PVS is associated with prognosis in the context of heart failure. This single-center study investigated the prognostic impact of PVS in patients undergoing transcatheter aortic valve implantation (TAVI). Methods: A total of 859 TAVI patients had been prospectively enrolled in an observational study and were included in the analysis. An optimal cutoff for PVS of −5.4% was determined by receiver operating characteristic curve analysis. The primary endpoint was a composite of all-cause mortality or heart failure hospitalization within 1 year after TAVI. Results: A total of 324 patients had a PVS < −5.4% (no congestion), while 535 patients showed a PVS ≥ −5.4% (congestion). The primary endpoint occurred more frequently in patients with a PVS ≥ −5.4% compared to patients with PVS < −5.4% (22.6% vs. 13.0%, p < 0.001). After multivariable adjustment, PVS was confirmed as a significant predictor of the primary endpoint (HR 1.53, 95% CI 1.05–2.22, p = 0.026). Conclusions: Elevated PVS, as a marker of subclinical congestion, is significantly associated with all-cause mortality and heart failure hospitalization within 1 year after TAVI.

Transductive Transfer Learning for Domain Adaptation in Brain Magnetic Resonance Image Segmentation

Segmentation of brain images from Magnetic Resonance Images (MRI) is an indispensable step in clinical practice. Morphological changes of sub-cortical brain structures and quantification of brain lesions are considered biomarkers of neurological and neurodegenerative disorders and used for diagnosis, treatment planning, and monitoring disease progression. In recent years, deep learning methods showed an outstanding performance in medical image segmentation. However, these methods suffer from generalisability problem due to inter-centre and inter-scanner variabilities of the MRI images. The main objective of the study is to develop an automated deep learning segmentation approach that is accurate and robust to the variabilities in scanner and acquisition protocols. In this paper, we propose a transductive transfer learning approach for domain adaptation to reduce the domain-shift effect in brain MRI segmentation. The transductive scenario assumes that there are sets of images from two different domains: (1) source-images with manually annotated labels; and (2) target-images without expert annotations. Then, the network is jointly optimised integrating both source and target images into the transductive training process to segment the regions of interest and to minimise the domain-shift effect. We proposed to use a histogram loss in the feature level to carry out the latter optimisation problem. In order to demonstrate the benefit of the proposed approach, the method has been tested in two different brain MRI image segmentation problems using multi-centre and multi-scanner databases for: (1) sub-cortical brain structure segmentation; and (2) white matter hyperintensities segmentation. The experiments showed that the segmentation performance of a pre-trained model could be significantly improved by up to 10%. For the first segmentation problem it was possible to achieve a maximum improvement from 0.680 to 0.799 in average Dice Similarity Coefficient (DSC) metric and for the second problem the average DSC improved from 0.504 to 0.602. Moreover, the improvements after domain adaptation were on par or showed better performance compared to the commonly used traditional unsupervised segmentation methods (FIRST and LST), also achieving faster execution time. Taking this into account, this work presents one more step toward the practical implementation of deep learning algorithms into the clinical routine.

Active Infective Native and Prosthetic Valve Endocarditis: Short- and Long-Term Outcomes of Patients after Surgical Treatment

Background: Active infective endocarditis (IE) is a serious disease associated with high mortality. The current study represents our experience over 18 years with surgical treatment for active infective native and prosthetic valve endocarditis (INVE, IPVE). Method: Analysis of 413 patients (171 with IPVE vs. 242 with INVE) who underwent cardiac surgery due to IE between 2002 and 2020. Results: Patients with IPVE were significantly older (64.9 ± 13.2 years vs. 58.3 ± 15.5 years; p < 0.001) with higher EuroSCORE II (21.2 (12.7; 41.8) vs. 6.9 (3.0; 17.0); p < 0.001)) and coronary heart disease (50.6% vs. 38.0%; p < 0.011). Preoperative embolization was significantly higher within INVE (35.5% vs. 16.4%; p < 0.001) with high incidence of cerebral embolization (18.6% vs. 7.6%; p = 0.001) and underwent emergency curative surgery than the IPVE group (19.6% vs. 10.6%; p < 0.001). However, patients with IPVE were significantly represented with intracardiac abscess (44.4% vs.15.7%; p < 0.001). Intraoperatively, the duration of surgery was expectedly significantly higher in the IPVE group (356 min vs. 244 min.; p = 0.001) as well as transfusion of blood (4 units (0–27) vs. 2 units (0–14); p < 0.001). Post-operatively, the incidence of bleeding was markedly higher within the IPVE group (700 mL (438; 1163) vs. 500 mL (250; 1075); p = 0.005). IPVE required significantly more permanent pacemakers (17.6% vs. 7.5%: p = 0.002). The 30-day mortality was higher in the IPVE group (24.6% vs. 13.2%; p < 0.003). Conclusion: Patients with INVE suffered from a higher incidence of cerebral embolization and neurological deficits than patients with IPVE. Surgical treatment in INVE is performed mostly as an emergency indication. However, patients with IPVE were represented commonly with intracardiac abscess, and had a higher indication of pacemaker implantation. The short- and long-term mortality rate among those patients was still high.

Influence of Age on Postoperative Neurological Outcomes after Surgery of Acute Type A Aortic Dissection

BACKGROUND

Acute type A aortic dissection (AAAD) is considered a fatal disease which requires an emergent surgical intervention. This study focuses onthe neurological outcome after surgical repair in cases of AAAD in comparison between elderly and young patients.

METHODS

a retrospective analysis of 368 consecutive patients who underwent emergency surgery of ascending aorta in moderate hypothermic circulatory arrest (MHCA) (20-24 °C) and antegrade cerebral perfusion after AAAD between 2001 and 2016. Patients were divided into two groups: those aged 75 years and older (68 (18.5%)) and those younger than 75 years (300 (81.5%)).

RESULTS

Comparing both groups, average age was 79.0 ± 3.2 vs. 59.2 ± 10.7 years (p < 0.001); female gender represents 58.8% of elderly patients vs. 28.7% in younger patients (p < 0.001). Intraoperatively, cardiopulmonary bypass time (155 min (131; 187) vs. 171 min (137; 220); p = 0.012), cross-clamping time (79 min (60; 105) vs. 93 min (71; 134); p = 0.001] and circulatory arrest time (29 min (22; 40) vs. 33 min (26; 49); p = 0.011) were significantly shorter in elderly than younger group. Postoperatively, there was no significant difference in delirium (11.8% vs. 20.5%; p = 0.0968) or stroke (11.8% vs. 16.1%; p = 0.369). The 30-day mortality was satisfactory for both groups but significantly higher in the elderly group (27.9% vs. 14.3%; p = 0.007).

CONCLUSION

The current study concluded that surgical treatment of AAAD in elderly patients can be applied safely without increasing risk of neurological complication. However, minimizing operation time may help limit the occurrence of postoperative neurological complication.

A fully convolutional neural network for new T2-w lesion detection in multiple sclerosis

•

A deep learning model for new T2-w lesions detection in multiple sclerosis is presented.

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Combining a learning-based registration network with a segmentation one increases the performance.

•

The proposed model decreases false-positives while increasing true-positives.

•

Better performance compared to other supervised and unsupervised state-of-the-art approaches.

Introduction: Longitudinal magnetic resonance imaging (MRI) has an important role in multiple sclerosis (MS) diagnosis and follow-up. Specifically, the presence of new T2-w lesions on brain MR scans is considered a predictive biomarker for the disease. In this study, we propose a fully convolutional neural network (FCNN) to detect new T2-w lesions in longitudinal brain MR images.

Methods: One year apart, multichannel brain MR scans (T1-w, T2-w, PD-w, and FLAIR) were obtained for 60 patients, 36 of them with new T2-w lesions. Modalities from both temporal points were preprocessed and linearly coregistered. Afterwards, an FCNN, whose inputs were from the baseline and follow-up images, was trained to detect new MS lesions. The first part of the network consisted of U-Net blocks that learned the deformation fields (DFs) and nonlinearly registered the baseline image to the follow-up image for each input modality. The learned DFs together with the baseline and follow-up images were then fed to the second part, another U-Net that performed the final detection and segmentation of new T2-w lesions. The model was trained end-to-end, simultaneously learning both the DFs and the new T2-w lesions, using a combined loss function. We evaluated the performance of the model following a leave-one-out cross-validation scheme.

Results: In terms of the detection of new lesions, we obtained a mean Dice similarity coefficient of 0.83 with a true positive rate of 83.09% and a false positive detection rate of 9.36%. In terms of segmentation, we obtained a mean Dice similarity coefficient of 0.55. The performance of our model was significantly better compared to the state-of-the-art methods (p < 0.05).

Conclusions: Our proposal shows the benefits of combining a learning-based registration network with a segmentation network. Compared to other methods, the proposed model decreases the number of false positives. During testing, the proposed model operates faster than the other two state-of-the-art methods based on the DF obtained by Demons.

P617Early global longitudinal strain predicts late infarct size in patients with anterior ST-segment elevation myocardial infarction treated with a primary percutaneous coronary intervention

Background

Late infarct size (IS) after STEMI is a determinant of subsequent mortality. Late Gadolinium enhancement in cardiac magnetic resonance imaging (LGE-CMRI) is the gold standard for IS measurement, however, it is not readily accessible in many areas.

Aims

To evaluate the value of early baseline 2D-echocardiographic global longitudinal strain (GLS) for prediction of late IS after STEMI.

Methods

From October 2017 to July 2018, we studied 100 patients with their 1st anterior STEMI treated with a PPCI. Baseline GLS calculation was performed within 48 hours of admission. The average value of the 9 segments supplied by the LAD was assessed separately (anterior GLS). Infarct size was assessed 3 months later using LGE-CMRI, and large infarcts were defined as ≥20% LV myocardium covered by scar.

Results

Based on CMRI, patients were divided into 2 groups; 57 patients with large infarcts (group I) and 43 patients with small infarcts (group II). Both groups were matched in all baseline demographics and risk factors. There was a good and significant correlation between GLS and the degree of myocardium affected by scar (r=−0.840, P<0.001). This correlation was even higher for anterior GLS (r=−0.867, P<0.001). ROC analysis showed a cut-off point of GLS (−13%) that identified large late IS with a sensitivity and specificity of 66.7% and 88.4% respectively (AUC= 0.85). For anterior GLS, the cut-off point was −9.6% (Sensitivity 94%, specificity 86%, AUC= 0.9).

Baseline 2D-GLS & Late LGE-CMRI

Conclusion

Baseline GLS significantly predicts and correlates well with late IS after anterior STEMI.

Un syndrome de Budd-Chiari associé à une thrombose veineuse portomésentérique : mode de révélation inhabituel d’une hémoglobinurie paroxystique nocturne

Le syndrome de Budd-Chiari (SBC) est une maladie vasculaire du foie faisant suite souvent à une thrombose veineuse sus-hépatique. L’hémoglobinurie paroxystique nocturne (HPN), affection clonale acquise rare, réalise une des conditions prothrombotiques bien connues prédisposant au SBC primitif. L’association SBC–HPN est souvent rapportée sous forme de cas cliniques isolés ou de petites séries présentant des spécificités pronostiques et thérapeutiques. Nous rapportons le cas d’une fille de 27 ans ayant une HPN révélée dans le cadre du bilan étiologique d’un SBC, associé à des thromboses veineuses portale, mésentérique et à une embolie pulmonaire.

Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study

BACKGROUND

Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery.

METHODS

This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy.

RESULTS

Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI.

CONCLUSIONS

After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.

Detection of Mycobacterium avium subsp. paratuberculosis in an Egyptian mixed breeding farm and comparative molecular characterisation of isolates from cattle, camels and cats – a case report

The present study records and investigates an outbreak of Johne’s Disease in a mixed breeding camel – cattle farm and the possible role of non-domestic non-ruminants animals in the epidemiology of Mycobacterium avium subspecies paratuberculosis in Egypt. For this reason, faecal samples were collected from 24 dairy cattle and from 15 one humped Arabian camels suffering from diarrhoea. Moreover, intestinal tissue samples were provided from 7 cats and 2 rats that were caught from the same farm and were euthanized before necropsy. Samples were examined using traditional culture and IS900 PCR techniques together with the application of BstEII-IS900 RFLP for typing of obtained isolates. Interestingly, MAP was recovered from cattle (n=8) and from camels (n=3) and non-domestic cats (n=3) reared under local conditions in this farm in Egypt. The obtained results highlight the potential role of cats in the epidemiology of MAP, a subject which needs further investigation and might have a public health importance, catsbeing common members of many families.

Torsade de pointes and systemic azole antifungal agents: Analysis of global spontaneous safety reports

Background: Literature about torsade de pointes induced by azole antifungal agents is scarce, despite the well-known association. Furthermore, little is known about the latency time between commencing an azole antifungal agent and developing torsade de pointes. The objectives of the present study were therefore to identify all cases of torsade de pointes associated with systemic azole antifungal use reported to the WHO monitoring centre (Uppsala, Sweden) and to determine the latency times between commencing the azole and developing torsade de pointes. Methods: Investigator-driven, retrospective, descriptive analysis of post-marketing pharmacovigilance data regarding systemic azole antifungal agents and the development of torsade de pointes reported to the WHO monitoring centre 1995-2015. Results: 191 cases were reported as follows: fluconazole 130, itraconazole 22, ketoconazole 5, posaconazole 1, voriconazole 33. More than half of all cases involved concomitant suspected or interacting drugs. The median latency times between starting the azole and developing torsade de pointes ranged from 1 (posaconazole) - 9.5 days (itraconazole), range <1-250). Conclusions: Clinicians should be aware of these features of azole-associated torsade de pointes, avoid interacting drugs if at all possible and monitor at-risk patients.