Computational evidence of glycosyl cations

Glycosyl cations are key intermediates in the glycosylation reactions taking place through a S_N1-type mechanism. To obtain a reliable description of the glycosylation reaction mechanism a combination of computational studies and experimental data such as kinetic isotopic effects is needed. Computational studies have elucidated S_N2-type glycosylation reaction mechanisms, but elucidation of mechanisms in which ion pairs can be formed presents some difficulties because of the recombination of the ions. Recent topological and dynamic studies open the door to the ultimate confirmation of the presence of glycosyl cations in the form of intimate ion pairs during certain glycosylation reactions. This review covers the state-of-the-art tools and applications of computational chemistry mainly developed during the last ten years to understand glycosylation reactions in which an oxocarbenium ion could be involved.

Preliminary Insights in Sensory Profile of Sweet Cherries

Sweet cherry (Prunus avium L.) is a fruit appreciated by consumers for its well-known physical and sensory characteristics and its health benefits. Being an extremely perishable fruit, it is important to know the unique attributes of the cultivars to develop cultivation or postharvest strategies that can enhance their quality. This study aimed to understand the influence of physicochemical characteristics of two sweet cherry cultivars, Burlat and Van, on the food quality perception. Several parameters (weight, dimensions, soluble solids content (SSC), pH, titratable acidity (TA), colour, and texture) were measured and correlated with sensory data. Results showed that cv. Van presented heavier and firmer fruits with high sugar content. In turn, cv. Burlat showed higher pH, lower TA, and presented redder and brightest fruits. The principal component analysis revealed an evident separation between cultivars. Van cherries stood out for their sensory parameters and were classified as more acidic, bitter, and astringent, and presented a firmer texture. Contrarily, Burlat cherries were distinguished as being more flavourful, succulent, sweeter, and more uniform in terms of visual and colour parameters. The results of the sensory analysis suggested that perceived quality does not always depend on and/or recognize the quality parameters inherent to the physicochemical characteristics of each cultivar.

Transdermal delivery of a somatostatin receptor type 2 antagonist using microneedle patch technology for hypoglycemia prevention

Hypoglycemia is a serious and potentially fatal complication experienced by people with insulin-dependent diabetes. The complication is usually caused by insulin overdose, skipping meals, and/or excessive physical activities. In type 1 diabetes (T1D), on top of impaired pancreatic α-cells, excessive levels of somatostatin from δ-cells further inhibit glucagon secretion to counteract overdosed insulin. Herein, we aimed to develop a microneedle (MN) patch for transdermal delivery of a peptide (PRL-2903) that antagonizes somatostatin receptor type 2 (SSTR2) in α-cells. First, we investigated the efficacy of subcutaneously administered PRL-2903 and identified the optimal dose (i.e., the minimum effective dose) and treatment scheduling (i.e., the best administration time for hypoglycemia prevention) in a T1D rat model. We then designed an MN patch using a hyaluronic acid (HA)-based polymer. The possible effect of the polymer on stabilizing the native structure of PRL-2903 was studied by molecular dynamics (MD) simulations. The results showed that the HA-based polymer could stabilize the PRL-2903 structure by restricting water molecules, promoting intra-molecular H-bonding, and constraining torsional angles of important bonds. In vivo studies with an overdose insulin challenge revealed that the PRL-2903-loaded MN patch effectively increased the plasma glucagon level, restored the counter-regulation of blood glucose concentration, and prevented hypoglycemia. The proposed MN patch is the first demonstration of a transdermal microneedle patch designed to deliver an SSTR2 antagonist for the prevention of hypoglycemia. This counter-regulatory peptide delivery system may be applied alongside with insulin delivery systems to provide a more effective and safer treatment for people with insulin-dependent diabetes.

Mitral valve prolapse: American versus European guidelines - which one is better

Funding Acknowledgements

Type of funding sources: None.

Introduction

According to the most recent recommendations of AHA, mitral valve prolapse (MVP) is defined as systolic displacement of the mitral leaflet into the left atrium (LA) of at least 2 mm from the mitral annular plane. The ESC recommendations define MVP, flail and billowing, according to the location of the leaflet tips in relation to the coaptation plan. Differences in outcomes considering these classifications are not established.

Purpose

To evaluate the differences in clinical presentation and outcomes of MVP considering AHA and ESC classifications.

Methods

Single-center retrospective study of consecutive patients with MVP (defined according to the AHA classification) documented in transthoracic echocardiogram between January 2014 and October 2019. Demographic, clinical, echocardiographic and electrocardiographic data were collected. The results were obtained using Chi-square and ANOVA tests.

Results

We included 247 patients (mean age 62.9 ± 18 years, 61% males) according to AHA classification; considering the ESC classification: 147 (59%) had prolapse, 30 (12%) flail and 67 (39%) billowing.

In comparison to patients with flail and billowing, patients with MVP had less cordae rupture (p = 0.02). Prolapse was associated with better survival (p = 0.037) and was an independent predictor of survival (OR = 0.372, CI95% [0.148-0.935], p = 0.035) Patients with flail were older in comparison to the ones with prolapse and billowing (71 ± 14 vs 63 ± 17 vs 60 ± 21 years, respectively, p = 0.022). Patients with flail were mostly men (80%, p = 0.028), with more significant mitral regurgitation (p = 0.003) and higher NYHA class (p = 0.018). They also had higher systolic pulmonary artery pressure (SPAP) (48 ± 23 vs 38 ± 18 vs 36 ± 12mmHg, p = 0.015) and higher values of LV mass and posterior wall thickness (144 ±32 vs 125 ± 44 vs 114 ± 37g/m2, p = 0.005 and 11 ± 1,5 vs 10 ± 1,7 vs 9 ± 1.9 mm, p = 0.009, respectively). Women had more billowing (p = 0.04) than prolapse and flail.

Conclusion

The ESC classification adds information to the AHA classification in what concerns to clinical presentation and prognosis of mitral valve prolapse, so both classifications should be used in daily practice.

Mitral annulus disjunction: is it a marker of ominous prognosis?

Funding Acknowledgements

Type of funding sources: None.

Introduction

Mitral annulus disjunction (MAD) has been proposed as a contributing factor for arrythmias and mitral regurgitation in patients with mitral valve prolapse (MVP), however its clinical relevance is still under investigation.

Objective

To evaluate the frequency of MAD in MVP patients, to characterize clinically patients with MAD and assess potential markers for events.

Methods

Single-center retrospective study of consecutive patients with MVP documented in transthoracic echocardiogram between January 2014 and October 2019. MVP was defined according to the 2017 AHA recommendations; MAD was defined as a separation between mitral valve annulus and the left ventricle free wall. Demographic, clinical, echocardiographic, electrocardiographic data were collected. The results were obtained using Chi-square and Mann-Whitney tests; logistic regression was used to find predictors of events.

Results

247 patients were included (mean age 62.9 ± 18 years, 61% males), of these 23 (9.3%) had MAD (mean age 56 ± 20 years, 56.5% males). The maximum diameter of MAD was 10 ± 3mm (range 5-18). 21 patients (92.3%) had mitral regurgitation, and it was at least of moderate severity in 65.2% of patients. Most of the patients (91.3, n = 21) were in sinus rhythm (SR).

During follow-up (FUP) of 29 ± 19 months, 39% (n = 9) of the patients developed symptoms, 22% (n = 5) had atrial fibrillation (AF), 4.3% (n = 1) had acute aortic syndrome (AAS), 4.3% (n = 1) needed ICD, 22% (n = 5) were submitted to mitral valve intervention, 8.7% (n = 2) were admitted to hospital and 8.7% (n = 2) died. None of the patients presented sustained ventricular arrhythmias (SVA) as assessed in regular Holter monitoring.

These patients had more AAS and needed more ICD in FUP compared to patients without MAD (p = 0.007 and p = 0.006, respectively)

Mitral cord rupture (p = 0.04), age (p = 0.044), maximum velocity of tricuspid regurgitation (p = 0.04) and IVS thickness (p = 0.017) were associated with AF in MAD patients. in univariate analysis, interventricular septum thickness was a predictor of AF in this subgroup (OR 4.0, 95%CI 1.1-14.3, p = 0-032) The presence of SR was associated with survival (p = 0.03). There were no predictors of hospital admission or mitral intervention.

Conclusion

Patients with MAD had a relatively benign prognosis with few events during follow-up, although with more AAS and ICD in FUP. In our sample, AF was more common than SVA. Left ventricle hypertrophy was a predictor of AF and sinus rhythm was associated with survival. Larger studies with more patients and other methods of imaging are needed to confirm our results.

Tissue-Specific Effects of Leptin on Glucose and Lipid Metabolism

The discovery of leptin was intrinsically associated with its ability to regulate body weight. However, the effects of leptin are more far-reaching and include profound glucose-lowering and anti-lipogenic effects, independent of leptin's regulation of body weight. Regulation of glucose metabolism by leptin is mediated both centrally and via peripheral tissues and is influenced by the activation status of insulin signaling pathways. Ectopic fat accumulation is diminished by both central and peripheral leptin, an effect that is beneficial in obesity-associated disorders. The magnitude of leptin action depends upon the tissue, sex, and context being examined. Peripheral tissues that are of particular relevance include the endocrine pancreas, liver, skeletal muscle, adipose tissues, immune cells, and the cardiovascular system. As a result of its potent metabolic activity, leptin is used to control hyperglycemia in patients with lipodystrophy and is being explored as an adjunct to insulin in patients with type 1 diabetes. To fully understand the role of leptin in physiology and to maximize its therapeutic potential, the mechanisms of leptin action in these tissues needs to be further explored.

Cracking in Sweet Cherry Cultivars Early Bigi and Lapins: Correlation with Quality Attributes

Fruit cracking is one of the main concerns in sweet cherry production and is caused by a heavy rainfall before and during the harvest. This physiological disorder leads to severe economic losses, which can be more or less effective depending on the cracked region of the fruit: in the cheeks (side cracks), in the stylar scar region, or in the stem cavity region. Sweet cherry cracking can be affected by several factors such as cultivar, growing conditions, rootstock, fruit size, flesh osmotic potential, cuticular characteristics of the skin, and stage of fruit development. In this sense, the objective of this work was to evaluate the cracking incidence in two sweet cherry cultivars (Early Bigi and Lapins grafted on "Saint Lucie 64" rootstock) and correlate the cracking index with other quality parameters. Fruits were harvested on 2 May (cv. Early Bigi) and on 27 May (cv. Lapins) 2019 at their commercial ripening stage. In the field, the total yield and the trunk cross-sectional area were determined for each tree in order to calculate the yield efficiency. In the laboratory, the cracking index was determined in 150 fruits without visual defects. In addition, fruit size and weight, wax content, flesh firmness, epidermis rupture force, total soluble solids, pH, titratable acidity, and maturity index of 30 fruits were also evaluated. In general, all the analyzed quality parameters were influenced by the cultivar, being that cv. Lapins presented larger, heavier, firmer, and sweeter fruits, with more acidity and higher maturation index. However, cv. Lapins also presented higher cracking index, which was positively correlated with all the parameters above-mentioned and negatively correlated with the wax content. In fact, cv. Early Bigi presented a high wax content and simultaneously a low cracking index. The stylar scar region cracks were the most prevalent in both cultivars. These results allowed us to conclude that, in the North Portugal region, the Lapins cherries presented better quality attributes than the Early Bigi cherries. However, the latter are still very valuable to the region due to its early ripening. Additionally, it was also possible to conclude that bigger, firmer, more mature, and with lower wax content cherries were more sensitive to cracking than the smaller fruits, soft-fleshed, less mature, and with higher wax content.

Are we aiming for different metabolic targets in heart failure patients?

Introduction

Metabolic control plays an important role on major cardiovascular events (MACE) prevention. The 2019 ESC guidelines on dyslipidaemia management recommend tighter LDL-cholesterol (LDL-C) control in order to prevent cardiovascular events. However, it is not yet proven that thigh control of dyslipidaemia, glycaemic levels and body mass index (BMI) in Heart Failure (HF) patients (pts) have an impact on prognosis.

Objective

To evaluate the impact of LDL-C, HbA1c and BMI values on HF pts mortality and MACE rates.

Methods

Single centre study that included consecutive pts hospitalized for acute / decompensated chronic HF in a tertiary Hospital between January 2016 to December 2018 and followed for 12 months. The impact of LDL-C, HbA1c and BMI on mortality and MACE was assessed using Cox regression and Kaplan-Meier curve, after adjustment for age, sex, functional class and ejection fraction. A safety cut-off was established when any of these variables was deemed protective using ROC curve analysis.

Results

Two hundred twenty-four patients (71.68±13.45 years, 63.8% males) were included. Eighty-four (37.5%) pts had type 2 diabetes, 39.7% had ischemic heart disease and the median left ventricular ejection fraction was 34% (IQR 25–49.5; 60.3% HFrEF; 13.8% HFmrEF; 22.3% HFpEF). The median BMI was 25.4 kg/m2 (IQR 23.1–30.5), HbA1c, 6.4% (IQR 5.6–6.8) and LDL-C, 89.5 mg/dL (IQR 64–106); 145 (64.7%) pts were medicated with statins. The overall mortality and MACE rates during follow-up were 16.1% and 21.0%, respectively. According to the CV risk classification 39.7% pts were at very high risk and 19.6% pts at high risk. On multivariate analysis HbA1c (HR 1.5 IQR 1.1–1.9; p=0.007) and female sex (HR 9.453 IQR 2.4–37.2; p=0.001) were independent predictors of mortality, whereas LDL-C (OR 1.05 IQR 1.022–1.075; p<0.001) and BMI (OR 1.23 IQR 1.075–1.404; p=0.002) were independent protective factors. LDL-C and BMI had no effect on MACE rates, although HbA1c was an independent predictor of MACE (HR 1.27 IQR 1.03–1.57; p=0.026). For high and very high-risk pts there was still a protective trend on mortality, although non-significant, for higher levels of LDL-C (OR 1.04 IQR 0.99–1.075; P=NS). Protective LDL-C cut-off were estimated for the whole population (LDL-C 88mg/dL; AUC 0.819; sn 56.6%, sp 100%) and for the high and very-high CV risk pts (LDL-C 84mg/dL; AUC 0.815; sn 59.3%; sp 100%). A BMI safety cut-off for mortality of 25.75 kg/m2 was found (AUC 0.627; sn 61.2%; sp 58.3%).

Conclusion

This study supports the theory of the obesity and LDL-C paradox in HF. Lower LDL-C and BMI increased mortality and there is no trade-off effect on MACE rates, supporting the idea that LDL-C and BMI should not be aggressively addressed in HF pts. In our cohort a cut-off level of LDL-C below 88mg/dL is associated with higher mortality. On the other hand, diabetes should be actively treated as HbA1c predicts death and MACE in HF pts.

Funding Acknowledgement

Type of funding source: None

Management practices for postdural puncture headache in obstetrics: a prospective, international, cohort study

BACKGROUND

Accidental dural puncture is an uncommon complication of epidural analgesia and can cause postdural puncture headache (PDPH). We aimed to describe management practices and outcomes after PDPH treated by epidural blood patch (EBP) or no EBP.

METHODS

Following ethics committee approval, patients who developed PDPH after accidental dural puncture were recruited from participating countries and divided into two groups, those receiving EBP or no EBP. Data registered included patient and procedure characteristics, headache symptoms and intensity, management practices, and complications. Follow-up was at 3 months.

RESULTS

A total of 1001 patients from 24 countries were included, of which 647 (64.6%) received an EBP and 354 (35.4%) did not receive an EBP (no-EBP). Higher initial headache intensity was associated with greater use of EBP, odds ratio 1.29 (95% confidence interval 1.19-1.41) per pain intensity unit increase. Headache intensity declined sharply at 4 h after EBP and 127 (19.3%) patients received a second EBP. On average, no or mild headache (numeric rating score≤3) was observed 7 days after diagnosis. Intracranial bleeding was diagnosed in three patients (0.46%), and backache, headache, and analgesic use were more common at 3 months in the EBP group.

CONCLUSIONS

Management practices vary between countries, but EBP was more often used in patients with greater initial headache intensity. EBP reduced headache intensity quickly, but about 20% of patients needed a second EBP. After 7 days, most patients had no or mild headache. Backache, headache, and analgesic use were more common at 3 months in patients receiving an EBP.

A landslide risk index for municipal land use planning in Portugal

In Portugal landslides caused 237 fatalities and >1600 displaced people in the period 1865-2015. Spatial distribution and temporal patterns of slope instability can be related with a complex set of natural and human factors responsible for generating damages. It is essential to develop new methodologies to synthetize risk dimensions to contribute to the landslide risk management at the municipal level. This work proposed a municipal landslide risk index (LRI) considering three risk dimensions: hazard, exposure and physical vulnerability of buildings. The hazard dimension includes the landslide susceptibility performed at the national scale, the probability of weather types associated with landslides and an extreme precipitation susceptibility index. The exposure dimension considered the population density and the number of buildings, whereas the average physical vulnerability of the buildings was computed using four statistical variables from the official census: (i) construction technique and construction materials; (ii) reinforced structure; (iii) number of floors; and (iv) conservation status. Each variable includes different classes that were empirically weighted. After evaluating the three risk dimensions and the LRI, a cluster analysis was performed in order to identify the most important landslide risk drivers in each municipality. Exposure is the main driving force of LRI in the metropolitan areas of Lisbon and Porto, while the hazard is more relevant in the NW municipalities and the physical vulnerability is the major driving force in the south of the country. This methodological approach contributes to a comprehensive and synthetized knowledge about the landslide risk driving forces within the 278 Portuguese municipalities. In addition, it contributes to the diversification and context-oriented strategies of landslide risk management that still lacks in most of the national-level risk governance processes. Finally, this methodology can be generalized to other geographical contexts, improving the risk management, land use planning and the disaster risk reduction.

Assessing the implementation of population based cervical cancer screening in Amadora, Portugal

Background

Population-based cervical cancer screening (CCS) are deemed to be more cost-effective than opportunistic screening and to reduce inequalities. Implementation in Portugal has been heterogeneous, at the regional level. In Amadora healthcare cluster (Lisbon area), implementation started in April 2018 in a pilot unit and was scaled-up. We aimed to assess population-based CCS implementation in Amadora.

Methods

Population-based CCS targets women aged 30-65, and utilises liquid-based cytology with partial HPV genotyping (HPV16/18 and other high-risk HPV - hrHPV). Samples positive for other hrHPV undergo a cytology. HPV16/18+ and other hrHPV+ with ≥ASCUS (atypical squamous cells of undetermined significance) are referred to colposcopy. We assessed implementation according to key indicators extracted from our information system: geographic coverage, number of tests, positive results, positive predictive value of referral (number of cervical intraepithelial neoplasia-CIN/number colposcopies).

Results

As of 30 August 2019, CCS were in place in 4 of the 9 units, potentially covering 20904 women (48.4% of the target population). 1797 womem performed screening within the programme. Invitation for screening is currently implemented in 1 of the 4 units. Screening results were available for 1702 women, 11,1% were HPV+. From these, 26,5% were HPV 16/18+ and 86.2% positive for other hrHPV. Among the latter, 63.2% were negative for intraepithelial lesion and 36.8% were ≥ASCUS. Overall, of these 189 women, 51.3% (n = 97) were referred for colposcopy. Colposcopy results were available for 37 women, of which 13 had a CIN. PPV of referral was 35.1% (95%confidence interval: 20.7;52.6).

Conclusions

Despite being a population-based screening most tests are still opportunistic. There is still a limited number of colposcopies results but the current PPV of referral is low and requires further investigation. Implementation towards a full population-based screening in Amadora should continue.

Key messages

Implementation of a population-based cervical cancer screening in Amadora, Portugal is underway but most screening tests are still applied in an opportunistic manner. A limited number of results is avaliable to estimate positive predictive value of referral to colposcopy. Results available indicate a value of 35.1%, which requires further investigation.

Trajectories of cognitive performance over 5 years in a cohort of breast cancer patients (NEON-BC)

Purpose

Cancer-related cognitive impairment may affect 30-70% of cancer patients, either at baseline or during and after treatment. We aimed to identify trajectories of cognitive performance, from before any treatment to 5 years later, in a cohort of breast cancer (BCa) patients.

Methods

BCa women admitted to the Portuguese Institute of Oncology, Porto, were included in the NEON-BC study during 2012. They were evaluated with the Montreal Cognitive Assessment (MoCA) before any treatment, and after 1, 3 and 5 years (N = 506, 503, 475 and 466, respectively). Nlme R package was used to fit a mixed-effect model of the trends in MoCA scores over time, with age and education as fixed effect. Coefficients of this model were retrieved to calculate an age- and education-modified MoCA score (mMoCA). Mclust was used to obtain clusters of trajectories of mMoCA.

Results

Two trajectories were identified, one with higher scores and increasing over time, and the other showing a continuous decline (25.9% of the participants and 84% of the women with cognitive impairment confirmed by neuropsychological tests and clinical examination by neurologist at the 5 year follow-up). Each trajectory was split into 2, according to scoring above or below to the median value of mMoCA at baseline to account for the possibility of patients being in a declining pathway before treatment. In addition to trajectories characterized by the highest and lowest scores, respectively, relatively stable over time, two trajectories with middle-range scores were observed, one increasing over time and the other decreasing (12.7% of the participants); being older than 65 years, suffering from anxiety, depression or poor sleep after treatment were more frequent among the latter.

Conclusions

One quarter of the 5-year breast cancer survivors had a declining trajectory in cognitive performance. Anxiety, depression and sleep quality should be considered as targets for preventive or curative interventions of cognitive decline.

Key messages

Cognitive decline occurs during breast cancer care, affecting one quarter of the patients. Anxiety, depression and sleep quality should be considered as targets for preventive or curative interventions of cognitive decline.

864A modified snare technique improves left ventricular lead implant success and response rate to cardiac resynchronization therapy

Introduction

Left ventricular (LV) lead placement is often the most challenging aspect of cardiac resynchronization therapy (CRT) device implantation, with a failure rate up to 10% due to complex coronary anatomies.

Purpose

To evaluate the efficacy of a modified snare technique in the LV lead implantation in cases of standard technique failure and to evaluate its impact in the response rate to CRT.

Methods

A prospective study was conducted of patients indicated for a CRT implant. When LV lead delivery to the target vessel failed using standard techniques, a modified snare technique was implemented, using a secondary coronary sinus delivery sheath introduced through the same venous puncture.  Patients were evaluated every 6 months. Efficacy was quantified by long-term surgical intervention rates. Patients were evaluated with transthoracic echocardiography before CRT implant and between 6-12 months post-implant. Patients with ejection fraction (EF) elevation ≥ 10% or LV end-systolic volume (ESV) reduction ≥ 15% were classified as responders. Patients with EF elevation ≥ 20% or LV ESV reduction ≥ 30% were classified as super-responders. Time to surgical revision and mortality were evaluated by the Cox regression and Kaplan-Meier methods.

Results

From 2015-2019, 566 CRTs were implanted (26.1% female, 72 ± 10.2 years old, follow-up duration 18.9 ± 15.8 months). The standard LV implant technique failed in 94 cases (16.6%), of which the modified snare technique was successful in 92 (97.9%) with LV lead implant in a lateral vein in 94.7% of cases. Baseline clinical characteristics were similar between patients who implanted LV lead with snare vs standard technique (p = NS). The 4-year surgical intervention rate was lower with the modified snare implant technique than with the standard technique (3.2% vs. 10.2%, HR 0.26, 95% CI 0.08-0.84, p < 0.05), with a relative risk reduction of 74% and a number needed to treat to prevent one surgical intervention of 14. The intervention rate was also lower regarding LV lead implant failure or dislodgement rates (0% vs. 5.3%, p < 0.05). Major complications were similar between groups.

In addition, the response rate to CRT was higher in the modified snare technique than in the standard approach (71.1% vs 55.0%, p < 0.05). In patients who implanted the LV lead with the snare technique, EF increased from 28.1 ± 8.2% to 36.1 ± 11.1% (p < 0.05) and LV ESV decreased from 127.8 ± 64.0mL to 99.8 ± 61.1mL (p = 0.01).

The super-response rate was similar between groups (33.3% vs 27.8%, p = NS).

Conclusion

For challenging coronary sinus anatomies that preclude LV lead placement by standard methods, this modified snare alternative was effective, with significantly lower surgical intervention rates and a higher response rate to resynchronization therapy. This higher than expected response rate with the snare technique, evaluated by remodeling criteria, may be explained by the implant of LV lead in the desired target lateral vein.

Abstract Figure.

Defining evacuation travel times and safety areas in a debris flow hazard scenario

Debris flows are one of the most hazardous types of landslides in mountain regions. In the upper part of the Zêzere valley (Serra da Estrela, Portugal) several debris flows events occurred in the last 200 years, some of them causing loss of lives and material damages. In this work, a methodology for pedestrian evacuation modelling, in a debris flow hazard scenario, was implemented. A dynamic run-out model, developed in previous studies, was used to evaluate the debris flows velocities, thickness of the deposits and extent of the mobilized material. The buildings potentially affected by the impact of debris flows were identified and the potentially exposed population was estimated by applying a dasymetric distribution. The results lead to the conclusion that, in the study area, the elderly are those who are most exposed to debris flows. Furthermore, the time lapse between the debris flows initiation and the arrival at the buildings at risk was estimated, allowing to account for the overall number of buildings where the evacuation time takes longer than the debris flows arrival. Additionally, the safe areas within the study area were identified, and several safe public buildings with the capacity to gather a large number of persons were selected. Considering that the study area is located in a mountain region, characterized by steep slopes, the evacuation modelling was performed based on an anisotropic approach, in order to consider the influence of slope direction on travel costs. At the end, three pedestrian evacuation travel time scenarios, based on different walking speeds to accommodate residents with different ages in safer places, were compared and the results mapped. The implemented methodology is not local dependent, which allows its reproduction elsewhere.

Overcoming environmental problems of biocides: Synthetic bile acid derivatives as a sustainable alternative

Marine biofouling represents a global economic and ecological challenge. Some marine organisms produce bioactive metabolites, such as steroids, that inhibit the settlement and growth of fouling organisms. The aim of this work was to explore bile acids as a new scaffold with antifouling (AF) activity by using chemical synthesis to produce a series of bile acid derivatives with optimized AF performance and understand their structure-activity relationships. Seven bile acid derivatives were successfully synthesized in moderate to high yields, and their structures were elucidated through spectroscopic methods. Their AF activities were tested against both macro- and microfouling communities. The most potent bile acid against the settlement of Mytilus galloprovincialis larvae was the methyl ester derivative of cholic acid (10), which showed an EC₅₀ of 3.7 μM and an LC₅₀/EC₅₀ > 50 (LC₅₀ > 200 μM) in AF effectiveness vs toxicity studies. Two derivatives of deoxycholic acid (5 and 7) potently inhibited the growth of biofilm-forming marine bacteria with EC₅₀ values < 10 μM, and five bile acids (1, 5, and 7-9) potently inhibited the growth of diatoms, showing EC₅₀ values between 3 and 10 μM. Promising AF profiles were achieved with some of the synthesized bile acids by combining antimacrofouling and antimicrofouling activities. Initial studies on the incorporation of one of these promising bile acid derivatives in polymeric coatings, such as a marine paint, demonstrated the ability of these compounds to generate coatings with antimacrofouling activity.

P871 Giant left ventricular (pseudo?)aneurysm complicating anterior myocardial infarction

Introduction

Clinical approach of cardiac aneurysms and pseudoaneurysms is significantly distinct. Therefore, it is crucial to accurately differentiate these two entities, which could be a real challenge.

Case report

We describe a case of a 55-year-old woman, with hypertension and previous smoking habits. She was admitted in our Cardiology Department with the diagnosis of anterior acute myocardial infarction, and was submitted to emergent coronariography, unveiling an occlusion of the middle segment of the anterior descending artery. She underwent successful primary percutaneous coronary intervention (PCI) 1h45 after the chest pain onset. Transthoracic echocardiogram (TTE) revealed depressed left ventricle ejection fraction (LVEF 30%), with akinesia of anterior and septal walls and all apical segments. She evolved in Killip-Kimbal class 2 and was discharged clinically stable. One week later, the patient performed a control TTE that showed an apical thrombus, with a small pericardial effusion, and she initiated warfarin. Three weeks later, a reevaluation TTE demonstrated a severe increase of the left ventricle dimensions, with LVEF 32%, and a small pericardial effusion. In apical 4-chambers incidence, it was visualized a linear structure (42 mm x 5 mm) attached to the endocardial border of the anterolateral apical segment and to the apical segment of the interventricular septum, of undefined nature. The apical segments were dyskinetic and had a very thin wall, which could correspond to aneurysm versus pseudoaneurysm. To clarify these findings, the patient performed a cardiac magnetic resonance revealing a large anterior myocardial infarction complicated with extensive myocardial necrosis, severe depression of LV systolic function (LVEF 25%) and septum rupture distal to the right ventricle apex (without connecting with it), compatible with a large apical pseudoaneurysm. The clinical case was discussed in the Heart Team and it was decided to perform cardiac surgery. However, surgical findings showed integrity of septal and free walls, and she underwent an aneurysmectomy, without further complications. Histological examination confirmed the presence of a thin myocardial wall with marked fibrosis and, consequently, the diagnosis of ventricular aneurysm. She was discharged clinically stable and maintains follow-up in Cardiology consultation of our Hospital.

Conclusion

In this patient, initially admitted with an anterior myocardial infarction submitted to primary PCI, follow-up with advanced imaging modalities pointed to the diagnosis of pseudoaneurysm. Despite the preoperative diagnosis, surgical findings were compatible with a giant left ventricular aneurysm. Even with high spatial resolution exams, postoperative evaluation of tissue layers remains the gold standard for this differential diagnosis.

Abstract P871 Figure. Apical pseudoaneurysm vs aneurysm

Litter traits and rainfall reduction alter microbial litter decomposers: the evidence from three Mediterranean forests

The objective of the study was to evaluate changes in microbial communities with the predicted arrival of new species to Mediterranean forests under projected intensification of water stress conditions. For that, litter from three Mediterranean forests dominated respectively by Quercus pubescens Willd., Quercus ilex L. and Pinus halepensis Mill. were collected, and placed to their 'home' forest but also to the two other forests under natural and amplified drought conditions (i.e. rainfall reduction of 30%). Quantitative PCR showed that overall, actinobacteria and total bacteria were more abundant in Q. pubescens and Q. ilex than in P. halepensis litter. However, the abundance of both groups was dependent on the forest sites: placement of allochthonous litter to Q. pubescens and P. halepensis forests (i.e. P. halepensis and Q. pubescens, respectively) increased bacterial and fungal abundances, while no effect was observed in Q. ilex forest. P. halepensis litter in Q. pubescens and Q. ilex forests significantly reduced actinobacteria (A/F) and total bacteria (B/F) to fungi ratios. The reduction of rainfall did not influence actinobacteria and bacteria but caused an increase of fungi. As a result, a reduction of A/F ratio is expected with the plant community change towards the dominance of spreading P. halepensis under amplified drought conditions.

Early anemia and neonatal morbidity in extremely low birth-weight preterm infants

Background: Extremely low birth-weight (ELBW) preterm infants remain at high risk for mortality and major morbidities, and nearly all need packed red blood cell transfusions within their first weeks of life. The overall objective of this study was to assess the association between anemia at admission to neonatal intensive care unit (NICU) with the neonatal morbidity and mortality in ELBW infants.Methods: This retrospective study was conducted on 106 patients with ELBW admitted at our level III NICU from January 2006 to December 2015. The subjects were divided into two groups: (1) patients with anemia at admission and (2) patients without anemia. Their characteristics and outcomes were compared. Statistical analysis was performed using the Statistical Package for the Social Sciences software, version 24.0 (IBM New York, USA), and a value of p < 0.05 was considered statistically significant.Results: Of the 106 ELBW, 34 (32%) presented with anemia at admission and 72 (68%) without anemia. Anemia-naive presented mean hemoglobin at the admission of 12.8 ± 1.5 g/dl and nonanemic 16.8 ± 2.1 g/dl, p < .001). The anemic group presented a lower gestational age (26 ± 2 vs. 27 ± 2 SD weeks, p = .025), greater need for inotropic support (52.9 vs. 31.9%, p = .041), longer period of invasive mechanical ventilation (9 vs. 2 days, p = .012), higher FiO₂ need (0.8 vs. 0.4, p < .001), more frequent hemodynamically significant patent ductus arteriosus (HS-PDA) (64.7 vs. 41.7%, p = .006) and severe intra-periventricular hemorrhage (IPVH) (41.2 vs. 16.7%, p = 0.005). The multivariate analysis confirmed an association between anemia at admission and HS-PDA (OR = 3.2; 95% CI: 1.1-9.5, p = 0.044) and severe IPVH (OR = 3.3; 95% CI: 1.0-9.9, p = .038). In anemic infants, ionotropic support and IPVH >2 were considered independent factors for mortality.Conclusion: In this ELBW series, the presence of anemia at admission to the NICU was associated with HS-PDA and severe IPVH. Preventive strategies for early anemia must be encouraged.

P1698Age shock index is a simple bedside clinical risk stratification tool in patients with non-ST-segment elevation myocardial infarction

Introduction

Shock index (SI), (heart rate (HR)/systolic blood pressure (SBP)), has been reported to predict worse outcomes in different acute settings. Two derivatives, named modified SI (MSI), defined as HR/mean BP; and Age SI, defined as SI multiplied by age, were later developed, but only the former was tested for short-term outcomes in patients with myocardial infarction (MI). We hypothesize that Age SI may demonstrate higher prognostic accuracy than SI and MSI due to the added prognostic value of age in this population.

Purpose

Compare the prognostic performance of admission age SI, MSI and SI for predicting in-hospital mortality in patients with NSTEMI.

Methods

Retrospective cohort study of consecutive patients admitted to the Cardiology department of a tertiary care hospital with the diagnosis of NSTEMI between October 2010 and September 2018. Very high-risk patients in need of emergent treatment were excluded. Of the initial cohort of 2476 patients, we excluded 5 who presented cardiac arrest before or at hospital admission, 4 with cardiogenic shock, 95 with acute pulmonary oedema, 10 with SBP <80 mmHg, 1 with HR <40bpm and 1 with HR >160bpm. The primary outcome was all-cause in-hospital mortality. The discriminatory capacity of Age SI, MSI, SI for the primary outcome was assed using the ROC-AUC and compared with the DeLong method, and the value with highest Youden-index was considered the optimal cut-off point. Calibration was assessed using the Hosmer-Lemeshow (HL) test and adjustment for confounding variables was performed using logistic regression analysis.

Results

2359 patients were included [mean age 66±13 years; 1732 (73.4%) men], of whom 40 (1.7%) died during hospitalization. Discrimination by ROC-AUC was highest for Age SI (0.78 [95% CI 0.71–0.86)], compared to MSI (0.69 [95% CI 0.61–0.78]) and SI (0.69 [95% CI 0.61–0.78)], p<0.01 for comparison. All indexes demonstrated adequate calibration (HL: Age SI 7.4; MSI 4.5; SI 6.4; p>0.5). The optimal cut-off for Age SI was 40, which was present in 684 patients (29%) and had 75% sensitivity, 72% specificity, 4.5% positive and 99.5% negative predictive value (NPV) for in-hospital mortality (4.4% vs 0.6%, p<0.001). After adjusting for covariates, an Age SI higher than 40 was associated with increased in-hospital mortality (adjusted OR 3.2, 95% IC 1.06–9.55), p=0.039).

Mortality and Age Shock Index

Conclusion

Age SI demonstrated better discriminatory capacity and equal calibration, compared to SI and MSI for in-hospital mortality. An age SI higher than 40 was associated with a 3-fold increased risk of in-hospital death. This cut-off demonstrated excellent negative predictive value (99.5%) and may allow very early risk assessment in patients with non-ST-segment elevation MI (NSTEMI), before laboratorial values are available for GRACE calculation. This may guide initial therapy and help select the most appropriate initial site of care.

P5689First intention epicardial VT ablation: what are the results?

Introduction

Ventricular tachycardia (VT) endocardial mapping and ablation may not be sufficient in several arrhythmogenic contexts, because ventricular myocardium may comprise intricate endocardial, intramural and epicardial substract. Thus, epicardial ablation has lately become a complementary and necessary tool to approach some VTs in different types of cardiomyopathies.

Purposes

To evaluate the clinical characteristics of patient most suitable for first intention epicardial VT ablation and to describe our centre experience.

Methods

Single-centre prospective study of consecutive patients (pts) undergoing isolated first intention epicardial VT mapping and ablation since August 2015. All pts had clinical assessment, electrocardiogram (ECG), echocardiogram and cardiac magnetic resonance when feasible. Pts with a previous endocardial ablation were excluded. Epicardial subxiphoid access utilizing a tuhoy needle was performed under fluoroscopic guidance. High-density mapping was performed using CARTO® V4 and EnSite PrecisionTM systems and multipolar catheters. Radiofrequency energy was applied with an irrigated-tip catheter.

Results

First intention epicardial VT ablation was attempted in 12 pts (mean age 57.6±14.6 years, 91% male). The majority had non-ischemic dilated cardiomyopathy, of unknown aetiology in 59%, hereditary dilated cardiomyopathy in 17% ethanolic origin in 8% and post-myocarditis in 8%. Right Ventricular Arrhythmogenic Cardiomyopathy was present in 1 patient. As expected, our population presented a mean ejection fraction of 29% and 11 pts (92%) had an implantable cardioverter defibrillator - ICD (55% as primary prevention, 45% as secondary prevention). All pts had experienced symptomatic VT, with all ICD carriers receiving appropriate shocks. Only 4 pts had an available 12 lead ECG of the VT, and all of them had a QS pattern in lead aVL and a slurred initial QRS complex. The majority of patients presented low voltage areas and local abnormal ventricular activities at the epicardial surface, with the exception of 2 pts in whom ablation was not performed (one non-ischemic cardiomyopathy of ethanolic aetiology and the other of unknown origin). Mean ablation application time was 68 minutes, with an average maximum power of 39.9 watts. Mean overall procedure and fluoroscopic time was 132 and 24 minutes, respectively, with no major intraprocedural complications. During a mean follow-up of 307±328 days, 3 pts died (mean 121 days after procedure), 3 had recurrent VT episodes and ICD shocks, and 2 received heart transplant.

Conclusion

In selected pts, with non-ischemic dilated cardiomyopathy and ECG with QS pattern in aVL and slurred QRS, epicardial VT mapping and ablation may be used as first approach, preventing unnecessary endocardial mapping. This procedure demonstrated to be safe.