Releasing antiferromagnetic skyrmions from local magnetic-anisotropy defects

Lattice defects may work as a kind of apparatus for catching topological excitations, preventing their escape. So, the problem of removing skyrmions from eventual local defects in magnetic materials must be closely related to new technologies such as skyrmionic. Here, we examine the conditions for drawing a skyrmion from a magnetic impurity in a two-dimensional antiferromagnetic system by applying spin-polarized currents (SPC). Two types of impurities are investigated (local easy-axis and easy-plane anisotropy defects). Also, two methods to release the skyrmion with SPC are explored. In principle, our results could be qualitatively relevant to any other type of lattice defect.

At the outer edge of STEMI time: even after 12 hours, the clock keeps ticking

Introduction

Although primary percutaneous coronary intervention (pPCI) is not a class I recommendation in all patients (pts) presenting within 12 to 48h of symptom onset (late ST-segment Elevation Myocardial Infarction, STEMI), there is increasing evidence supporting its routine use in this population. Data on long-term clinical outcomes is sparse.

Objective

To evaluate long-term MACE in late-STEMI pts submitted to pPCI and compare with clinical outcomes of early reperfusion groups.

Methods

Retrospective analysis of consecutive pts submitted to pPCI due to STEMI between 2010 and 2015 in a pPCI centre. Included pts were stratified in 5 groups according to symptom-to-balloon time (SBT): <3h; 3–6h; 6–12h; 12–24h; 24–48h. Of a total of 903 pts, 19 pts were excluded due to SBT >48h. Long-term events were established as 5y mortality and 5y-MACE (a composite endpoint of death, re-infarction, heart failure hospital admission and ischemic stroke). The cumulative incidence of long-term outcomes was calculated by the Cox regression analysis and presented according to the Kaplan-Meier method.

Results

Of the 884 pts included in the study, stratification according to SBT was: pPCI<3h (47.4%), pPCI 3–6h (24.9%), pPCI 6–12h (16.5%), pPCI 12–24h (8.0%), and pPCI 24–48h (3.2%). These groups showed no significant difference in terms of demographic characteristics (age, CV risk factors, previous coronary disease or heart failure), clinical severity (systolic arterial pressure, Killip-Kimball class, left ventricle ejection fraction) and angiography findings (multivessel disease, complete revascularization and PCI success). After a median follow-up of 76 (56; 98) months, 5-year mortality was 20.6% (182 pts) and 5-year MACE was 23.3% (206 pts). MACE was associated with increased median SBT: 5.0 (2.0; 9.0) hours vs 4.0 (2.0; 6.5) hours, p<0.001. Of the MACE components, the only that showed a significant association with higher median SBT was mortality: 5.0 (2.0; 10.0) hours vs 4.0 (2.0; 6.0), p<0.001. Differences in long-term outcomes were significant when considering SBT stratified by revascularization time (Figure 1).

Conclusions

As expected, there is a clinical benefit of early reperfusion for long-term cardiovascular events. Within the late-STEMI group, there seems to be a clear distinction between pPCI<24h and >24h, although the clinical benefit of pPCI timing most probably acts a continuum.

Funding Acknowledgement

Type of funding sources: None.

Percutaneous coronary intervention in elderly patients with chronic kidney disease and non-ST segment elevation acute coronary syndrome – is it worth it?

 

ESC guidelines recommend revascularization in patients (pts) with chronic kidney disease (CKD) irrespective of age. However, elderly pts are usually underrepresented in the available data on percutaneous coronary intervention (PCI). Thus, the decision on whether to perform PCI in these pts is usually at the discretion of the cardiology team.

Aim

To evaluate the impact of PCI vs conservative approach (CA) in elderly pts (>80 years) with CKD and unstable angina (UA)/non-ST segment elevation myocardial infarction (NSTEMI) who were enrolled in the Portuguese National Registry of Acute Coronary Syndromes. To determine impact of CKD in in-hospital (IH) and long-term outcomes, including MACE (myocardial infarction, stroke and death) and death at 1 year.

Study population

Elderly pts admitted with UA and NSTEMI, from 2010 until 2021. There were three different groups: Group 1 – eGFR ≥60 ml/min/1.73 m2; Group 2 – eGFR between 30 and 59 ml/min/1.73 m2 and Group 3 – eGFR <30 ml/min/1.73 m2. Pts with ST-segment elevation myocardial infarction and cardiogenic shock were excluded.

Results

A total of 2443 pts, of which 921 (37,7%) were submitted to PCI. 50,2% (n=1126,) were from the group 1, 38,5% (n=941) from group 2 and 11.3% (n=276) from group 3.

Regarding overall population, pts submitted to PCI were mainly male (60,4%) with a mean age of 84±3 years old. They had previous history of PCI (21,6% vs 15,1% p<0.001), less history of heart failure (HF), stroke or dementia (8,5% vs 16,5%; 8,1 vs 13.3% and 2,1 vs 5,9%, p<0.001). At presentation they had more angina (88,8% vs 81,2% p<0.001), less NT-proBNP levels (387 vs 561 p<0.001) and were more frequently in KK class I (75,6% vs 70,2% p=0.004). They developed less HF (21% vs 27%, p<0.001) and MACE (5,7% vs 9,1% p=0.003). Pts in the group 3 were less submitted to PCI (27,5% vs 38,2% vs 39,6% p<0.001) and had more MACE and cardiovascular death when comparing to group 2 and 1 (16,1% vs 8,7% vs 5,3% and 10,5% vs 5,5% vs 2,6% p<0.001 respectively).

Comparing PCI vs CA in each group, there was no difference in IH outcomes between both strategies in group 3. The same was not true for groups 1 and 2, in which PCI seemed to favor overall outcomes (p=0.001 and p=0.015 respectively).

The predictors of IH death and MACE were: age (OR 1.068 p=0.010), dementia (OR 2,376 p=0.015), KK class >1 (OR 2,243, p<0.001), atrial fibrilhation (OR 1.605, p=0.046), not having PCI (OR 0.309, p<0.001), eGFR <30 (OR 3.51, p<0.001) and PCI in pts with eGFR <30 (OR 2.923, p=0.019).

Interestingly, survival analysis showed that pts submitted to PCI in all 3 groups (including group 3) had a longer 1-year survival (p<0.001, p<0.001 and p<0.004).

Conclusions

PCI performance in elderly pts with CKD should be individualized. In our population, especially in group 3, the performance of PCI is associated with a higher IH mortality, however, after surviving hospitalization, these pts seem to have a benefit in 1 year survival.

Funding Acknowledgement

Type of funding sources: None.

Should we stay or should we go: assessment of the need for the implantation of a definite pacemaker in a population of acute coronary syndrome that evolved in advanced atrioventricular block

Introduction

The incidence of advanced atrioventricular block (AVB) secondary to acute coronary syndrome (ACS) has been decreasing in the era of percutaneous revascularization and in most cases is transitory and does not require pacemaker (PM) implantation.

Purpose

Our aim was to assess the characteristics of patients with AVB as a consequence of the ACS and compare those with and without PM implantation, in what regards in-hospital and at 1 year outcomes.

Methods

We performed a retrospective analysis of all patients admitted with AVB secondary to ACS in Portugal between October of 2010 and August of 2021 with data from the Real World Portuguese Registry on Acute Coronary Syndromes (ProACS). Medical records were analysed for demographic, procedural data and outcomes.

Results

Sex hundred and seventy one (671) patients with AVB secondary to ACS were admitted, which corresponded to 2.2% of the total cohort. The mean age was 70±13 with a male preponderance (66%). The ACS was categorized as ST elevation Myocardial Infarction (STEMI) in 76.4%, non-STEMI (NSTEMI) in 22.1%, and unstable angina (UA) in 1.5%. Of the patients admitted with AVB, 8.6% implanted a permanent PM. The was no clinically relevant differences in both groups in what regards to medical priors or medication. Regarding the location of the infarction, an Anterior STEMI was the diagnosis of admission in 36.8% (vs 14.5%; OR 3.45, CI 95% 1.31–9.06, p<0.05) of patients that implanted a PM, and the left descending artery was more frequently the culprit artery, and an Inferior STEMI was the diagnosis of 63.2% (vs 83.7%; OR 0.31, CI 95% 0.12–0.82, p<0.05) of patients and a right coronary artery was more frequently the culprit artery.

The presence of cardiovascular shock and in-hospital death was significantly more frequent in the group that did not implant a PM (OR 0.40; CI 95% 0.17–0.95, p<0.05 and OR 0.33; CI 0.12–0.92, p<0.05 respectively) and the implantation of PM was a negative predictor of in-hospital death (OR 0.28; CI 95% 0.08–0.93, p<0.05).

The follow up at 1 year was performed in two hundred and sixty three (263) patients, 10.6% with an implanted PM. The survival analysis demonstrated increased mortality and a combined end-point of death and readmissions in the population of AVB that did not implant PM compared with a population who did not present with AVB (p<0.05) with the Kaplan Meier curves widening significantly (Figure 1). This difference was not observed compared with an AVB population that implanted PM.

Conclusions

In patients with AVB secondary to ACS, the implantation of a PM might have been withheld in more severe patients, accounting for the increased mortality observed, and this population has worse outcomes at 1 year, leaving open to the hypothesis if either due to a more severe clinical status or the recurrence of AVB.

Funding Acknowledgement

Type of funding sources: None.

Association between common cardiovascular risk factors and clinical phenotype in patients with hypertrophic cardiomyopathy from the European Society of Cardiology (ESC) EurObservational Research Programme (EORP) Cardiomyopathy/Myocarditis registry

AIMS

The interaction between common cardiovascular risk factors (CVRF) and hypertrophic cardiomyopathy (HCM) is poorly studied. We sought to explore the relation between CVRF and the clinical characteristics of patients with HCM enrolled in the EURObservational Research Programme (EORP) Cardiomyopathy registry.

METHODS AND RESULTS

1739 patients with HCM were studied. The relation between hypertension (HT), diabetes (DM), body mass index (BMI), and clinical traits was analysed. Analyses were stratified according to the presence or absence of a pathogenic variant in a sarcomere gene. The prevalence of HT, DM, and obesity (Ob) was 37, 10, and 21%, respectively. HT, DM, and Ob were associated with older age (P<0.001), less family history of HCM (HT and DM P<0.001), higher New York Heart Association (NYHA) class (P<0.001), atrial fibrillation (HT and DM P<0.001; Ob p = 0.03) and LV (left ventricular) diastolic dysfunction (HT and Ob P<0.001; DM P = 0.003). Stroke was more frequent in HT (P<0.001) and mutation-positive patients with DM (P = 0.02). HT and Ob were associated with higher provocable LV outflow tract gradients (HT P<0.001, Ob P = 0.036). LV hypertrophy was more severe in Ob (P = 0.018). HT and Ob were independently associated with NYHA class (OR 1.419, P = 0.017 and OR 1.584, P = 0.004, respectively). Other associations, including a higher proportion of females in HT and of systolic dysfunction in HT and Ob, were observed only in mutation-positive patients.

CONCLUSION

Common CVRF are associated with a more severe HCM phenotype, suggesting a proactive management of CVRF should be promoted. An interaction between genotype and CVRF was observed for some traits.

Comparison of 2-years follow-up of optimal medical therapy versus balloon pulmonary angioplasty for inoperable chronic thromboembolic pulmonary hypertension

Introduction

Balloon pulmonary angioplasty (BPA) has emerged as a therapeutic option for chronic thromboembolic pulmonary hypertension (CTEPH) considered ineligible for pulmonary endarterectomy (PEA). The initial publications showed very good short-term outcomes for the technique, but there are limited data regarding medium-term outcomes and its comparison with optimal medical treatment (OMT).

Objectives

To evaluate and compare the medium-term outcomes of OMT versus (vs) BPA in inoperable CTEPH.

Methods

Retrospective study of consecutive patients (pts) with CTEPH followed in a referral centre for Pulmonary Hypertension. Selected those pts considered ineligible for PEA and with at least 2 years of follow-up. Comparison between two treatment strategies: OMT alone [maximum tolerated doses of pulmonary vasodilator drugs (PVD), as indicated] vs BPA (pts who completed the program with or without OMT). Endpoint was a composite of all-cause death and unplanned right heart failure admission at 2-year.

Results

From 62 pts, 19 pts were included (11 pts were excluded due to recent diagnosis; 32 were submitted to EAP): mean age 65.0±15.3 years, 89.5% female. At diagnosis, all pts had functional capacity limitation and elevated serum NTproBNP levels (median value 1255.0 pg/mL). Mean pulmonary arterial pressure (mPAP) was 46.2±9.3 mmHg and pulmonary vascular resistance (PVR) 15.3±8.3 Wood units (WU). Concerning treatment, 12 pts (63.2%) underwent OMT alone. These pts had higher NTproBNP levels (2670.0 vs 538.0 pg/mL, p&lt;0.01) and PVR values (19.7±7.6 vs 9.7±5.4 WU, p=0.01) and lower CI (1.6±0.3 vs 2.4±0.5 L/min/m2, p&lt;0.01), at baseline; the remaining basal features didn't differ among groups (Fig.A). At 2-year follow-up, pts submitted to BPA were under PVD in 71.4% of cases with a mean of 1±0.8 drugs per patient and no difference compared to OMT group (83.3%, 1.7±0.9 drugs per patient), although oxygen therapy was higher in medical group (50% vs 0%, p=0.04). A significant overall improvement was observed in BPA group (Table – A): all pts were in functional class I (p&lt;0.01), no one had right ventricular dysfunction (p&lt;0.01) and mPAP decreased to 25.1±6.7 mmHg (p=0.01) and RVP to 2.9±0.8 WU (p=0.01). Inversely, no change was observed in pts under OMT alone (p&gt;0.05 in all, Table – A). Endpoint rate was 31.6% with all adverse events occurring in the OMT group (50% vs 0%, p=0.04). After adjustment by Cox regression, no difference in baseline or follow-up features besides treatment influenced the outcome. Kaplan-Meier analysis (Graphic – B) confirmed significant benefit of BPA in 2-year outcome occurrence (long rank 4.6, p=0.03).

Conclusions

BPA strategy seems to improve medium-term functional capacity, right ventricular function and haemodynamics and decrease oxygen therapy dependence in inoperable CTEPH. Pts under OMT alone have a poor prognosis. These data encourage the development and implementation of the technique for inoperable CTEPH.

Funding Acknowledgement

Type of funding sources: None.

Left atrial appendage velocity as an instrument of predicting atrial fibrillation recurrence after successful catheter ablation – a useful tool?

Introduction

Catheter ablation for the treatment of Atrial Fibrillation (AF) is a modality of treatment in growing expansion. However the sustained long term response in preventing AF recurrence is poor for most patients, namely in those with a dilated left atrium.

Purpose

Our aim was to assess the utility of an echocardiographic parameter for left atrium function, the left atrial appendage velocity (LAAV), in predicting recurrences after catheter ablation.

Methods

We performed a 9 year retrospective analysis of all patients who underwent a successful catheter ablation for the treatment of atrial fibrillation and had a valid pre-procedural transesophagic echocardiogram in a single expert centre. Medical records were analysed for demographic, procedural data and outcomes.

Results

Seventy-three (73) patients fulfilled all inclusion criteria and were analysed. The mean age was 62±11 with a male preponderance (58,7%). The majority of patients (82,7%) had preserved left ventricle ejection fraction. Only 46% of patient had a volumetric assessment of the left atrium dimensions prior to ablation, with slight, moderate and severe dilation of the left atrium in 20%; 8,6% and 28,6% of patients. Of the patients subjected to an AF ablation the average LAAV was 50,6±19 cm/s, with 78% of patients with normal atrial appendage velocities.

Patients with low LAAV (&lt;40cm/s) had a higher proportion of AF recurrences at 3 and 6 months (58,3 vs 12,8% and 89% vs 21,7%; p&lt;0,05 for all) with a linear correlation between the presence of recurrences and LAAV (LAAV of 39,1 vs 57,5 cm/s; p&lt;0,05 OR 0,91 (CI 95% = 0,85–0,97); r2=0,34 at 3 months and LAAV of 43,5 vs 59 cm/s; p=0,01; OR 0,94 (CI 95% = 0,89–0,99); r2=0,24 at 6 months respectively). There was a trend towards association with recurrences at 1 year although it did not reach statistical significance. There was no significant difference in the use of antiarritmic drugs, either prior or post ablation, in both groups. It was not possible to assess the additive predictive value to the left atrium dimensions due to the low percentage of volumetric assessment of left atrium prior to AF ablation.

Conclusions

Patients with low left atrial appendage velocities had a lower long term success rate of catheter ablation, with higher rates of recurrence at 3 and 6 months and a trend towards higher recurrences at 1 year, with linear correlation which hypothesises the use of the left atrial appendage velocity as novel predictive parameter for an integrative model.

Funding Acknowledgement

Type of funding sources: None.

STEMI around-the-clock: how off-hours admissions impact door-to-balloon time and the long-term prognosis of ST-segment Elevation Myocardial Infarction

Introduction

The outcomes of reperfusion in ST-segment Elevation Myocardial Infarction (STEMI) are time-dependent, and percutaneous coronary intervention (PCI) should be performed within 60 minutes from hospital admission in PCI centers – door-to-balloon time (D2B). The association between Off-Hours Admission (OHA) and long-term outcomes is controversial when considering contemporary organized STEMI networks.

Purpose

This study aims to analyze how OHA influences D2B and long-term mortality.

Methods

Retrospective study of consecutive STEMI patients (pts), admitted in a PCI-centre with a local Emergency Department, between 2010 and 2015. Pts submitted to rescue-PCI were excluded. OHA was defined as admission at night (8p.m. to 8a.m), weekends and nonworking holidays. Predictors of OHA and D2B were studied by logistic regression analysis. Demographic, clinical, angiographic and procedural variables were evaluated using stepwise Cox regression analysis to determine independent predictors of 5-year all-cause mortality (5yM). The cumulative incidence of 5yM stratified by hours of admission was calculated according to the Kaplan-Meier method.

Results

Of 901 pts, 472pts (52.4%) were admitted during off-hours. These pts were younger (61±13 vs 64±12, p=0.002) and had a lower median patient-delay time (128min vs 157min, p=0.014). Clinical severity at presentation, defined by systolic arterial pressure and Killip-Kimball (KK) class, did not differ between groups. OHA did not impact D2B (89 min vs 88 min, p=0.550), which was in turn influenced by age ≥75y (OR 1.85, 95% CI 1.31–2.61, p&lt;0.001). Mean clinical follow-up (FUP) was 68±37 months, with 75.1% of pts achieving a FUP &gt;5 years. 5yM rate was 9.7%. After multivariate cox regression analysis, independent determinants of long-term mortality were age (HR 1.05, 95% CI 1.02–1.08, p&lt;0.001), previous history of heart failure (HR 6.76, 95% CI 1.32–34.72, p=0.022) and pulmonary disease (HR 3.79, 95% CI 1.16–12.33, p=0.027), presentation with KK ≥2 (HR 2.82, 95% CI 1.32–6.01, p=0.007) and radial artery access in catheterization (HR 0.39, 95% CI 0.18–0.83, p=0.014) – figure 1. Although there was an association between a higher D2B time and 5yM (87min vs 101min, p=0.024), neither OHA nor D2B were independent predictors of long-term mortality – figure 2.

Conclusion

OHA did not seem to influence D2B and long-term STEMI outcomes in our PCI-centre. 5yM was mostly influenced by patient characteristics and clinical severity at presentation.

Funding Acknowledgement

Type of funding sources: None. Figure 1. Predictors of long-term mortalityFigure 2. 5-year survival stratified by OHA

Contrast-induced nephropathy after staged balloon pulmonary angioplasty: lower risk compared with left-sided cardiac procedures

Introduction

The risk of contrast-induced nephropathy (CIN) after left-sided cardiac procedures is reported as 10–15%. When the ratio of total contrast volume in ml to glomerular filtration rate (GFR) in mL/min (ratio V/GFR) exceeds 3.7, the risk increases significantly. However, there are few reports regarding the risk of CIN in patients (pts) with right-sided cardiac interventions such as balloon pulmonary angioplasty (BPA) and ratio V/GFR is not validated for use in this procedures.

Purpose

To assess the prevalence of CIN in pts with chronic thromboembolic pulmonary disease with or without hypertension (CTEPH/CTED) undergoing BPA.

Methods

Prospective single-centre study that included all BPA sessions performed from 2017 to 2020. Serum creatinine concentration (SC) was measured and the GFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI) before and 48 hours after each BPA procedure and 6 months after BPA treatment completion. CIN was defined as an increase of ≥25% and/or ≥0.5 mg/dL in SC from the baseline value within 48h of contrast administration.

Results

76 consecutive BPA sessions were performed in 15 CTEPH/CTED pts: mean age 63.2±14.0 years, 60% female, 86.7% CTEPH, mean of 5.3±1.9 sessions per patient with 4.3±1.9 vessels dilated per session. Mean value of GFR before BPA program was 73.5±26.3 mL/min. All the procedures were performed using low-osmolality contrast agent with a 1:1 dilution ratio with normal saline solution. Pts received 273.0±73.0 mL of contrast per session with a ratio V/GFR 3.7±1.7 mL. SC and GFR did not change significantly within 48h after BPA (+3.1%, p=0.07 and −3.0%, p=0.13, respectively). Ratio V/GFR &gt;3.7 occurred in 44.3% of cases (n=31), but CIN occurred in only 5.3% (n=4) with an increase in SC &lt;0.5 mg/dL but ≥25% in 3 cases (+33% in mean) and ≥0.5 mg/dL in 1 case. None of the pts required renal replacement therapy. Higher SC and lower GFR 48h after BPA were significantly correlated with greater rato V/GFR during procedure (r=0.75, p&lt;0.01 and r=−0.74, p&lt;0.01, respectively) – see figure. But neither higher values of ratio V/GFR (OR 1.43; CI95% 0.84–2.41; p=0.19) nor V/GFR &gt;3.7 (OR 1.28; CI95% 0.17–9.6; p=0.81) were predictors of CIN. GFR before procedure did not influence the contrast volume administered (p=0.901), number of vessels (p=0.63) and segments treated by session (p=0.45). At 6 months follow-up, there was a trend for SC (1.3±0.2 mg/dL vs 1.1±0.2 mg/dL, −15%, p=0.43) and GFR (44.5±8.3 mg/dL vs 53.0±12.6 mg/dL, +16%, p=0.34) improvement in pts with impaired renal function at baseline (GFR&lt;60 mL/min).

Conclusions

These findings suggested that the occurrence of CIN after BPA was low, raising the hypothesis that the influence of contrast agent on renal function could differ in right-sided cardiac interventions. Although the ratio V/GFR may be correlated with the risk of nephropathy, it is necessary to find a new cut-off to predict CIN in BPA pts.

Funding Acknowledgement

Type of funding sources: None.

One-year follow-up of continuous aspiration mechanical thrombectomy for the management of intermediate-high and high-risk pulmonary embolism: what is the line between utility and futility?

Introduction

Percutaneous catheter-directed treatments have emerged at the last decade for the management of acute high- or intermediate-high-risk pulmonary embolism (PE). Good short-term efficacy and safety have been published, but there are limited data regarding medium- to long-term outcomes.

Purpose

This study aimed to evaluate 1-year all-cause mortality of acute high- and intermediate-high-risk PE patients (pts) treated with continuous aspiration mechanical thrombectomy.

Methods

Twenty-nine consecutive pts with acute central PE (mean age 67.2±14.4 years; 72.4% female; 24.1% active cancer; Charlson comorbidity index 4.5±2.1; 82.8% in class&gt;III of original PESI score; 44.8% high-risk PE) were treated with the Indigo Mechanical Thrombectomy System (Penumbra, Inc) between 03/2018 and 03/2020. Clinical success was defined as improvement in hemodynamic and/or oxygenation parameters or pulmonary hypertension or right heart strain at 48 hours after intervention plus survival to hospital discharge. Data regarding severe adverse events potentially related to the procedure, in-hospital and 1-year all-cause mortality were collected.

Results

Clinical success was 75.9%, with a significant improvement in mean paO2/fiO2 ratio (+77.1±103.2; p&lt;0.01), shock index (−0.4±0.4, p&lt;0.01), need for aminergic support (−75.0%, p&lt;0.01), right ventricular function (66.6%, p&lt;0.01) and systolic pulmonary arterial pressure (−10.2±11.5mmHg, p&lt;0.01) at 48 hours after procedure. In-hospital survival rate was 82.8% but severe adverse events potentially related to the procedure occurred in 3 pts (10.3%). One-year follow-up was completed in 93.1% of cases and all-cause mortality rate was 34.5% (n=10 of which half occurred during the index hospital stay). Higher scores of Charlson comorbidity index (5.8±1.9 vs 3.7±1.9, p=0.01) and de novo atrial fibrillation at admission (40% vs 0%, p&lt;0.01) were associated with higher 1-year all-cause mortality occurrence and were identified as 2 independent risk predictors by multivariate Cox regression. Kaplan-Meier curves confirmed its significant influence in 1-year survival free of adverse event (Figure). Time among diagnosis and percutaneous treatment (p=0.99), PESI score (p=0.24) and other clinical, haemodynamic and echocardiographic features did not influence mortality and suggest similarity of the PE severity at baseline. Technical characteristics were also not associated with mortality.

Conclusions

Aspiration thrombectomy for acute high- and intermediate-high-risk PE was feasible with a high clinical success rate. One-year all-cause mortality rate was elevated and predicted by high comorbidity index and de novo atrial fibrillation at admission. This data support the national expansion of this new PE treatment, but probably and as similar to other invasive techniques, we need to take into account comorbidities and avoid futility in multimorbidity pts.

Funding Acknowledgement

Type of funding sources: None.

Complications of balloon pulmonary angioplasty for chronic thromboembolic pulmonary disease according to the classification proposed by the 6th world symposium on pulmonary hypertension

Introduction

Balloon pulmonary angioplasty (BPA) is a complex procedure and not risk free. In an attempt to standardize reports of BPA complications in the several centers, a classification of complications was proposed by the task force on chronic thromboembolic hypertension (CTEPH) in the 6th World Symposium on Pulmonary Hypertension (WSPH).

Purpose

To determine the prevalence of BPA complications according to the classification of 6th WSPH and to identify its predictors.

Methods

Detailed procedural and technical aspects were collected for consecutive patients (pts) with inoperable, residual/recurrent chronic thromboembolic disease, undergoing BPA at a single institution from December/2017 to December/2020. Per procedure logistic regression analysis was used to evaluate the predictive variables for complications.

Results

A total of 76 BPA sessions in 15 pts were performed (mean age 63.2±14.0 years; 60.0% women; 86.7% CTEPH). Mean pulmonary artery pressure and pulmonary vascular resistance before the first BPA session were 33.1±13.3 mmHg and 4.8±3.2 woods unit, respectively (73.3% of pts under vasodilator therapy). Femoral access was used for all pts. Mean vessels treated per procedure were 4.3±1.9 (324 vessels in total). Webs, subtotal occlusions, ring-like stenosis and total occlusions were noted in 215 (66.4%), 58 (17.9%), 31 (9.6%) and 20 (6.2%) treated vessels, respectively. We performed 21 pressure-wire-guided sessions (27.6%). Intravascular imaging was used in 6 procedures (7.9%). Average time of fluoroscopy was 60.3±14.0 minutes and volume of contrast 273.0±73.0 mL per session. Procedure-related adverse events occurred in 25.0% of the interventions (27.6% in the first two years vs 16.7% in the last two). Pulmonary artery vascular injuries were noted in 6 BPA vessels (7.9% per procedure and 1.9% per treated vessel): haemoptysis in all, but perforation was only detected angiographically in 3 of them (balloon inflation was performed for 2 distal perforations, and 1 perforation sealed without any intervention). Vascular dissection in distal lesions occurred in 4 cases (5.3%) with no need of transcatheter or surgical procedures. We had 3 lung injuries, all grade 2. None of the pts required oral intubation or mechanical ventilation. Extra-pulmonary complications were illustrated in table. Importantly, there was no peri-procedural death. The occurrence of vascular or lung injuries was 0% in pressure-wire-guided BPA versus 14.5% in non-guided (p=0.098). Multivariate analysis revealed that age (OR 1.05; CI 1.01–1.10; p=0.030) was the only independent predictor of complications.

Conclusions

In our experience, BPA can be safely performed in inoperable, residual or recurrent CTEPH or CTED pts, with 25% minor procedural-related complications but no major adverse event. Age was the strongest factor related to the occurrence of complications.

Funding Acknowledgement

Type of funding sources: None.

Flat scalp melanoma dermoscopic and reflectance confocal microscopy features correspond to histopathologic type and lesion location

Background

Dermoscopy and Reflectance Confocal Microscopy (RCM) features of scalp melanoma according to lesion location and histopathology have not been fully investigated.

Objectives

To reveal dermoscopic and RCM features of scalp melanoma according to lesion location and histopathology.

Methods

We retrospectively retrieved images of suspicious, atypical excised, flat melanocytic lesions of the scalp, assessed on dermoscopy and RCM at five centres, from June 2007 to April 2020. Lesions were classified according to histopathological diagnoses of nevi, lentigo maligna melanoma (LM/LMM) or superficial spreading melanoma (SSM). Clinical, dermoscopic and RCM images were evaluated; LM/LMM and SSM subtypes were compared through multivariate analysis.

Results

Two hundred forty‐seven lesions were included. In situ melanomas were mostly LM (81.3%), while invasive melanomas were mostly SSM (75.8%). Male sex, baldness and chronic sun‐damaged skin were associated with all types of melanomas and in particular with LM/LMM. LMs were mostly located in the vertex area and SSM in the frontal (OR: 8.8; P < 0.05, CI 95%) and temporal (OR: 16.7; P < 0.005, CI 95%) areas. The dermoscopy presence of pseudo‐network, pigmented rhomboidal structures, obliterated hair follicles and annular–granular pattern were associated with LM diagnoses, whereas bluish‐white veil was more typical of SSM. Observations on RCM of atypical roundish and dendritic cells in the epidermis were associated with SSM (42.4%) and dendritic cells with LM (62.5%) diagnoses. Folliculotropism on RCM was confirmed as a typical sign of LM.

Conclusions

Flat scalp melanomas reveal specific dermoscopic and RCM features according to histopathologic type and scalp location.

Scattering modes of skyrmions in a bilayer system with ferromagnetic coupling

Magnetic skyrmions are quasiparticle-like textures that are topologically different from a single domain magnetization state. Their topological protection, combined with the low current density needed to move them, make these objects relevant to be used as information storage structures. In such a context, the analysis of the interactions between skyrmions is interesting and relevant for future applications. In this work, through micromagnetic simulations and numerical calculations, we studied the interaction between two skyrmions living on different parallel ferromagnetic racetracks connected by an exchange-like interaction. The upper and lower racetracks are separated by a height offset and the interaction between the upper and the lower skyrmion is analyzed in terms of the magnetic and geometrical parameters. Three states are predicted, as a function of these parameters: scattered or free skyrmions, bound skymions, and annihilated skyrmions. Our results, presented in a phase diagram, demonstrate that even in the case here called free skyrmions, there is a small and brief interaction when both are close enough, but the skyrmion in the top layer does not drag the skyrmion in the bottom layer. For bound skyrmions, both keep linked during larger times. In the latter case, there are strong changes in the velocity of the skyrmions induced by the effect of a higher effective mass when both are coupled.

Magnus-force induced skyrmion-antiskyrmion coupling in inhomogeneous racetrack

In this paper we investigate a magnetic racetrack consisting of a junction of three materials with different properties. Indeed, this magnetic system is composed by two distinct regions (racetracks) connected by a thin interface: the first region (termed sector 1) has isotropic in-plane magnetic chirality and supports skyrmion (S) excitations while the second (sector 3) has anisotropic chirality and consequently supports antiskyrmions (A). The interface, which would be a third region (sector 2, connecting sectors 1 and 3) located in the central part of the racetrack, is an easy-axis Heisenberg ferromagnetic material. The topological structures S and A are put in motion by applying a spin-polarized current. Under certain conditions, we show that the skyrmion and the antiskyrmion created in their respective sectors are simultaneously impelled to the interface (due to the Magnus force) to apparently become a unique object (a skyrmion-antiskyrmion pair or SAP). After glued by sector 2, the skyrmion and the antiskyrmion move together (as a SAP) along the direction of the applied current. It is also shown that such an engineered racetrack can support a sequence of several SAP structures in motion, forming a current.

Lentiginous melanoma (lentigo maligna and lentigo maligna melanoma) in Australia: clinicopathological characteristics, management and recurrence rates after 10-year follow-up at a tertiary centre

BACKGROUND

Lentiginous melanoma or lentigo maligna is a slow-growing type of melanoma frequently arising in sun-damaged skin and often first diagnosed in the elderly. Few studies report long-term follow-up.

OBJECTIVES

To define characteristics of lentiginous melanoma in situ (LM) and invasive lentiginous melanoma (LMM) in Australian patients managed at a tertiary centre and describe local recurrence or treatment failure rates after long-term follow-up.

METHODS

Retrospective single-centre study of LM/LMM patients evaluated between January 2005 and March 2007. Medical and photographic records were reviewed.

RESULTS

One hundred two patients were included, with a total of 117 lesions (70 LM and 47 LMM). Seventy-nine were new primary LM/LMM, and 38 were recurrences. Primary cases were mostly pigmented (71%), while 77% of recurrent cases were partially pigmented/light brown or amelanotic. The margins were clinically ill-defined in the majority of cases (64% of primary cases and 94% of recurrent cases). Dermoscopy of the primary LM/LMM showed either classic 'common' melanoma features (33%) or classic LM/LMM features (41%), while 95% of recurrent cases had no features for melanoma or LM/LMM. Primary cases that were initially excised (113, 97%) had mean histopathological clear margins of 4.9 mm (range 0.1-22 mm). The median follow-up time was 7.5 years (95% CI 5.2-10.0) with more than 10-year follow-up in 32% and 5-10 years in 24% of patients. There were 44 (38%) recurrences over the entire follow-up period. Half of the patients who recurred did so within the first 3.8 years after the first treatment.

CONCLUSION

LM/LMM often recur late and are clinically subtle; therefore, careful monitoring and long-term follow-up are required.

Predictors of the presence of septal late gadolinium enhancement in follow-up cardiac magnetic resonance imaging and its relation to acute myocarditis prognosis

Funding Acknowledgements

Type of funding sources: None.

Introduction

Acute myocarditis (AM) is generally a self-limited and benign disease. However, a minority of patients (pts) present or develop adverse outcomes. It has been proposed that the presence of late gadolinium enhancement (LGE) in the septum is associated with worse prognosis. Also, the presence of LGE without oedema in follow-up cardiac magnetic resonance imaging (CMR) seems to reflect more permanent lesions.

Purpose

The aim of this study was to determine if the presence of septal LGE in acute-phase CMR was associated with higher extent of disease in follow-up CMR and if initial laboratory tests help to predict the evolution to more permanent lesions.

Methods

Prospective single-centre study of pts admitted with AM diagnosed according to clinical findings, troponin T elevation and CMR criteria (Lake Louise), since 1/2013. Selection of those who underwent acute-phase (CMR-I) and follow-up CMR (CMR-II).

Results

Of 88 pts admitted with AM, 46 fulfilled our inclusion criteria: median age 31 ± 13 years, 85% males. CMR-I was performed at 6 ± 5days and LGE was present in 43 pts (93.5%). CMR-II was performed at 8 ± 4.3 months and 29 pts (63%) improved the number of LGE-positive segments, 10 pts (21.8%) had stable disease and 7 pts (15.2%) worsened CMR findings. Septal-LGE was detected in 10 pts (21.7%) in CMR-I and in 6 pts (13.0%) in CMR-II. Logistic regression analysis identified septal-LGE in CMR-I as a predictor of higher extent of LGE in CMR-II (OR 1.4, 95%CI 1.1-1.9, p = 0.020). Although median values of maximum high-sensitivity troponin and reactive-C protein (RCP) were not associated with septal LGE in CMR-I, increasing values of such tests were univariate predictors of a higher likelihood of septal involvement in CMR-II: maximum troponin (886 vs 1852ng/L; OR 1.00, 95%CI 1.00-1.00 p = 0.017) and RCP (4.2 vs 13.9mg/dL; OR 1.17, 95%CI 1.04-1.33, p = 0.012). After multivariate analysis, RCP was the independent predictor of septal LGE in CMR-II (AUC 80.8, 0.97-0.91, p = 0.012). RCP cut-off value &gt;10.2mg/dL identified patients with septal LGE in CMR-II with a sensitivity and specificity of 83.3% and 85.0%, respectively. The presence of cardiovascular risk factors, clinical presentation and B-type natriuretic peptide values were not predictors of septal LGE in either CMR. In a mean clinical follow-up of 757 ± 476days, no patient died, 3 pts (6.5%) developed new-onset heart failure (NYHA class II functional symptoms) and 2 pts (4.3%) developed ventricular arrhythmias. Due to a small number of adverse events, neither laboratory tests nor LGE septal pattern predicted adverse outcomes.

Conclusions

In this population, septal LGE pattern was able to predict higher extent of LGE in follow-up CMR. Increased cardiac biomarkers and inflammatory proteins in the acute setting were also associated with septal involvement in follow-up and can potentially help to establish the risk of adverse events for patients admitted with acute myocarditis.

Assessment of the CHA2DS2-VASc score in predicting ischemic stroke and death in patients with acute myocardial infarction without atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

onbehalf

on behalf of the investigators of the Portuguese Registry of Acute Coronary Syndromes

Introduction

The CHA2DS2-VASc score is used in clinical practice to stratify the risk of stroke in patients (pts) with atrial fibrillation (AF). Its usefulness in the population of pts with acute myocardial infarction without AF is not well known.

Objectives

To investigate whether CHA2DS2-VASc predicts ischemic stroke and death during hospital stay in pts with acute myocardial infarction without known AF. To determine independent predictors of ischemic stroke in this population.

Methods

A multicentre, retrospective study was performed during 01/10/2010-04/09/2019 period, and included all pts admitted due to acute myocardial infarction. Pts with previous AF, AF rhythm in the electrocardiogram at admission or AF during hospital stay were excluded. Statistical analysis with Kaplan-Mayer and Cox regression was applied.

Results

Of 29851 pts admitted with acute myocardial infarction, were included in our study 19218 pts (74% male, mean age of 65 ± 14 years). 

During hospital stay, 78 (0.4%) pts had an ischemic stroke and 462 (2.4%) pts died. 

The event-free survival analysis showed significant differences according to the CHA2DS2-VASc score at admission (log rank test p = 0.015 for ischemic stroke; log rank test p &lt; 0.001 for in-hospital mortality). (Figure) 

The CHA2DS2-VASc score demonstrated a good predictive accuracy for in-hospital mortality (area under the ROC curve 0.69; 95% CI 0.67-0.72; p &lt; 0.001). The area under the ROC curve indicates that the CHA2DS2-VASc score performed modestly for ischemic stroke (0.62; 95% CI 0.56-0.68; p &lt; 0.001). 

In univariate analysis, the factors that were positively associated with ischemic stroke during hospital stay were CHA2DS2-VASc, absence of previous therapy with statin, time between cardiac symptoms and hospital admission, absence of chest pain, Killip-Kimball class, cardiorespiratory arrest, complete left ventricular block and left ventricle ejection fraction &lt;50% (p &lt; 0.05). 

After multivariate analysis, CHA2DS2-VASc≥3 (HR 2.25; 95% CI 1.37-3.71; p = 0.001), absence of chest pain (HR 3.17; CI 1.44-6.14, p &lt; 0.001) and previous therapy with statin (HR 0.39; 95% CI 0.22-0.67; p = 0.001) were independent predictors of ischemic stroke.

Conclusion

 Among patients with acute myocardial infarction without known atrial fibrillation, the CHA2DS2-VASc score was associated with risk of ischemic stroke and death during hospital stay. This score may be useful for estimating the risk of stroke and in-hospital mortality in these population without known atrial fibrillation.

Abstract Figure.

Access of the LGBTQI+ population from the perspective of community health agents, Brazil

Introduction

In Brazil, according to the National Policy for Integral Health for Lesbians, Gays, Bisexuals, Transvestites, Transsexuals, Queers, Intersexuals and other identities (LGBTQI+), it is increasingly necessary to guarantee access to the health system, as well as to train qualified professionals.

Objective

describing the perception of Community Health Agents (CHA) about the approach to and access of LGBTQI+ people to primary health care.

Methods

Quantitative research conducted in October 2019 with 60 community health workers from the municipality of Rio de Janeiro, Brazil. The research was approved by the Ethics and Research Committees of the participating institutions.

Results

it was found that 100% of the CHA have already supported LGBTQI+ people, 19.2% identify prejudiced attitudes and delay in service as barriers to accessing the unit, and 19.2% recognize the presence of group activities in the unit. In the view of the CHA interviewed, LGBTQI+ patients could be approached in groups (50%), individually (19.2%) or both (30.8%). Among the strategies to increase the access of those patients, 61.5% are unaware and 38.5% listed possible strategies to be implemented in the unit. The topics of interest for discussion were: approach to reception, sexual identity, prejudice, psychological support, family, diseases, violence, and rights.

Conclusions

From the perspective of community health agents, the study allowed reflections on how approaching and making access available to LGBTQI+ patients in the primary care network. This evidences stigmas and fragility of professionals in the individual and collective approach to deal with issues regarding guidance sexuality and gender identity of the clientele served. It is important to emphasize permanent education actions among professionals, aiming at a comprehensive health care for the LGBTQI+ population.

Key messages

Welcoming and qualified listening promote comprehensive health care for the LGBTQI+ population. Improvements in the access of the LGBTQI+ population to the primary health care network decrease morbidity and mortality.

475 A rare cause of right ventricular mass

Introduction

Intracardiac masses are always a challenging diagnosis, especially when it involves the right side of the heart. There are multiples etiologies that can be responsible for these masses, namely thrombosis, neoplasm or vegetations. Occasionally, these may be related to an autoimmune process not yet discovered.

Case Report

17-year-old male, with a previous history of genital ulcers, medicated with penicillin with complete resolution of symptoms.

In January 2019, he started an history of recurrent fever, associated with right anterior thoracalgia, weight loss and oral afthosis. He went to the emergency department several times, where he was medicated with antibiotic, with partial symptom relief.

Three months later, he returned to medical attention due to an episode of abundant hemoptysis, followed by hematemesis and cough. At hospital admission, he was hemodynamically stable, tachycardic (100/min) and with occasional episodes of cough. Cardiac and pulmonary auscultation were unremarkable. Thoracic CT revealed the presence of pulmonary thromboembolism (PTE) and a large mass in the right ventricle (RV). It was performed an echocardiogram (echo) that confirmed the presence of a large mass in the RV (50x53mm) from which a projecting hypermobile mass appeared to prolapse into the right atrium.

Taking into account the diagnosis of PTE and the presence of a right ventricular mass, the patient was hospitalized and started anticoagulation. The case was immediately discussed with cardiac surgery, that confirmed that there was no surgical indication. During hospitalization, there were no more episodes of hemoptysis or hematemesis.Consecutive echos were performed, that did not reveal a significant decrease in mass dimensions despite anticoagulation. Viral serologies and autoimmunity panel were all negative. Cardiac RMI was performed raising the suspicion of a possible mass covered with thrombus.

After discussion with rheumatology, and according to clinical signs, the hypothesis of vasculitis was placed, and the patient started treatment with steroids. This treatment had to be suspended after a few days due to an infectious intercurrence. After a course of antibiotic therapy, the patient started therapy with cyclophosphamide with good clinical and echocardiographic response (reduced mass dimensions).

It was admitted Behçet’s disease with cardiac complications, and the patient was referred to the rheumatology consultation.

Conclusion

Behçet’s disease is a multi-system, chronic disorder that behaves like vasculitis.There are some typical clinical manifestations associated with this disease, such as oral and genital afthosis, uveitis, arthritis, skin lesions and nervous system involvement.Presentations with cardiac symptoms are one of the extremely rare manifestations of this disease, posing a challenge for the treating physician.

Abstract 475 Figure. Right ventricular mass

107 Low-flow low-gradient aortic stenosis: aortic valve area estimated by continuity equation versus simplified method of projected aortic valve area

Introduction

The evaluation of real severity of "low-flow low-gradient" aortic stenosis (LFLG AS) is particularly challenging. TOPAS study demonstrated that projected aortic valve area at a normal transvalvular flow rate (AVAproj) derived from dobutamine stress echocardiography (DSE) is superior to the traditional Doppler indices to discriminate true severe-AS and pseudosevere-AS.

Purpose

To compare two echocardiographic methods to estimate severity of LFLG AS with DSE (aortic valve area (AVA) estimated by continuity equation (AVA-CE) and simplified method of AVAproj) in patients (pts) with low transvalvular flow rate (&lt;250mL/seg).

Methods

Unicentric, retrospective study, that included pts with LFLG AS undergoing DSE with low dose dobutamine protocol, during Nov 2013-Dec 2018 period. Evaluation at rest and peak DSE of vital signs, mean transaortic gradient, aortic VTI, LVOT VTI and VTI ratio, valvulo-arterial impedance (ZVA), AVA-CE, simplified method of AVAproj and global longitudinal strain (GLS).

Results

A total of 27 DSE were performed in 23 different pts, mean age of 76 ± 8 years, 82% male. At rest 55% in sinus rhythm, mean heart rate (HR) was 76 ± 12 bpm, mean systolic arterial pressure (SAP) was 122 ± 22 mmHg, mean ZVA 4.3 ± 2 mmHg/ml/m2; mean diameter of LVOT was 21,7 ± 2,6cm, mean of mean aortic gradients 21 ± 7 mmHg, 67% of pts had a VTI ratio at rest compatible with severe AS and remaining compatible with moderate AS. Estimated mean AVA-CE was 0.86 ± 0.29 cm2 with 67% of pts classified as severe AS. Mean left ventricular ejection fraction at rest was 31 ± 9%, systolic volume index 28,7 ± 8 mL/m2 and GLS -5,9%.

During low dose perfusion protocol of dobutamine

100% patients remained asymptomatic, mean HR was 110 ± 25 bpm, mean SAP was 123 ± 26 mmHg, mean ZVA 3.6 ± 1.7 mmHg/mL/m2, mean of mean aortic gradients 28 ± 9mmHg, 37% of pts presented VTI ratio compatible with severe AS and remaining compatible with moderate AS. Mean flow reserve was 16 ± 16% and mean GLS-7.2%. AVA-CE was 1,06 ± 0,35 cm2 with 56% of pts classified as severe AS and mean projected AVA was 1.01 ± 0.22cm2, without significant difference in AVA estimated by the two methods (p = 0.344). Projected AVA allowed re-classification of AS in 22% of pts (5 patients), with 31% of severe AS reclassified as moderate AS while AVA-CE allowed re-classification in 13% (3 patients), with 19% of severe AS reclassified as moderate AS.

Considering medium follow up of 24 months, 6 patients were submitted aortic valve replacement surgery and another 6 patients to transcatheter aortic valve replacement. The simplified projected valve area calculation show no significant therapeutic impact in the selection of this patients.

Conclusion

The simplified projected valve area calculation is technically feasible and accessible. This study shows a good correlation in pts with low cardiac flow. If AVAproj method had been used 2 extra patients would have been reclassified during DSE.

P1808 The impact of valve type in morbimortality of patients with infectious endocarditis

Introduction

Infectious endocarditis (IE) represents one of the main causes of morbimortality in patients (pts) with valvular heart disease. Prosthetic valves infection is usually associated with worse outcomes.

Aim

To compare the clinical features and adverse outcomes of patients with native vs prosthetic valve IE.

Methods

We analysed a population with suspected/confirmed IE, according to Duke criteria, in the last 12 years (2006-2017). The clinical and imaging data were collected as well as complication rates and mortality data.

Results

174 pts, 75% males with mean age of 61 ± 16 years. Native valve EI occurred in 74,1%. of pts. 25,3% had heart failure (HF), 16,1% chronic kidney disease(7,1% on haemodialysis), 12,8% HIV infection, 9,3% active neoplasm and 7,1% were on immunosuppression. 16 pts with native valve disease had previous valvular disease: 1 congenital valve disease, 2 with rheumatic heart disease, 3 with previous IE and 10 with degenerative disease. At admission: 73,1% had fever, 53,2% murmur and 47,9% anemia. The majority (78,4%) had single valve IE and 15,8% had double valve involvement. Aortic valve (AoV) was affected in 54% of the cases and mitral valve involvement was seen in 43,7%. 13,3% had right valve disease. S. Aureus was the most frequent microrganism. Echocardiographic findings: 87,7% had vegetation, 21,2% valve destruction , 5,6% valve obstruction, 14,3% abscess, 3,7% valve aneurysm, 5,6% pseudoaneurysm and 5,6% fistula. Regurgitation was observed in 62,1%. The intrahospitalar mortality was 29,9%.

Comparing both groups, pts with prosthetic IE had more previous history of HF (40,5% vs 20,5% p = 0,009) and diabetes (31,7% vs 15,3% p = 0,020). No differences were found in what concerns microrganisms involved.

Echocardiographically, pts with prosthetic valve had predominantly AoV involvement (81,1% vs 45,5% p &lt; 0,001), less vegetation (75% vs 91,8% p = 0,01) and less regurgitation (45% vs 67,8% p = 0,01). They had more local complications (61% vs 27,7% p&gt; 0,001) like valve obstruction (12,5% vs 3,3% p = 0,043), abscess (32,5% vs 8,3% p&gt; 0,001) or pseudoaneurysm (17,5% vs 1,7% p= 0,001).

In what concerns morbidity burden, developed more HF during hospitalization (56,1% vs 37,7% p= 0,037) as well as more isquemic and haemorragic stroke(85,7% vs 42,3%. P = 0,004 and 28,6% vs 2,4% p = 0,012, respectively). However there were no differences regarding the development of septic shock (p = 0,542) or overall embolization (p = 0,732). At last, no differences were found in intrahospitalar(IH) mortality (p = 0,085), relapse (p = 0,573) or overall survival between both groups (log rank: 1,5, p = 0,217).

Conclusion

Pts with prosthetic valve IE usually have worse outcomes. However,for this population,we conclude that besides having more HF and stroke, there were no differences in what concerns septic shock or overall embolization, as well as IH mortality and survival between both groups.

P975Safety and clinical outcomes of rotational atherectomy: an eleven-year centre experience

Introduction

Rotational atherectomy (RA) is an adjunctive tool for the management of heavily calcified coronary lesions during percutaneous coronary intervention (PCI), but the clinical outcomes remain unclear. Access site choice is also poorly defined and there is growing evidence that transradial approach (TRA) is associated with lower complications and lower mortality.

Objectives

To assess the safety and long-term outcomes of RA for calcified coronary lesions and to investigate the influence of vascular access site in the efficacy and safety of the procedure.

Methods

Retrospective single-centre study that included consecutive PCI with RA performed from January 2006 to December 2017. Endpoint was a composite of major adverse cardiac events (MACE), defined as cardiovascular death, nonfatal myocardial infarction, nonfatal stroke and target vessel revascularization, at 1- and 5-year.

Results

246 procedures were included in a total of 236 patients (pts): mean age 70.1±9.7 years, 73.6% male; 36.2% had previous PCI, 12.2% vascular peripheral disease (VPD), 24% reduced left ventricle ejection fraction (LVEF) and 6.9% were under hemodialysis. PCI with RA was mostly performed due to stable angina (48.9%) and via TRA (55.3%), with a total of 371 treated segments and a median number of 1 vessel treated per intervention. The left anterior descending artery was the most frequently treated artery (67.5%). Single burr was used in 76% of cases (mean number of burrs 1.23; mean burr size 1.5 mm). Procedural success rate was 94.7%. Complications were recorded in 9.3%, with no procedure related death. Clinical follow-up was complete in 98.8% of pts at 1-year and 81.3% at 5-year (mean time 62.3±41.8 months). Survival free of MACE at 1- and 5-year were 83.7% and 73.2%, respectively. Multivariate Cox regression identified 6 independent predictors (only 1 protector) for 1-year MACE (Fig. A) and 6 independent predictors (all of increased risk) for 5-year MACE (Fig. B). TRA was protector of 1-year MACE and Kaplan-Meier curves showed benefit for both 1- and 5-year MACE occurrence (Fig. C and D), without significant difference in procedural success (p=0.92) and complications (p=0.45) rate comparing to transfemoral approach.

Conclusions

RA followed by stenting was a safe procedure with a high immediate success rate but an increased number of long-term cardiovascular events. Some clinical conditions, such as previous PCI, VPD and reduced LVEF, seems to adversely influence the long-term outcome while TRA appears to be protective.

P846Discriminatory power of the grace score in non-ST segment elevation myocardial infarction in the real world: results from the portuguese registry on acute coronary syndromes

Introduction

Current clinical practice guidelines recommend risk stratification in patients with acute coronary syndrome (ACS) upon admission to the hospital. The Global Registry of Acute Coronary Events (GRACE) risk score was developed in a large multinational registry to predict both mortality and the combined events of death or reinfarction during the hospital stay and 6 months after discharge. Given the substantial regional variation and temporal changes in patient characteristics and management patterns, specially in non-ST segment elevation myocardial infarction (NSTEMI) patients, we sought to validate this risk score in a contemporary Portuguese population.

Purpose

To assess the discriminatory power of the GRACE risk score in a Portuguese contemporary cohort of patients with NSTEMI submitted to invasive strategy, regarding in-hospital mortality and the combined end-point of reinfarction and/or in-hospital mortality.

Methods

We included patients with NSTEMI submitted to coronary angiogram from the Portuguese Registry on Acute Coronary Syndrome (ProACS). For each patient, we calculated the GRACE risk score and classified them in low, intermediate or high risk, according to the cut-offs recommended in the guidelines. The discriminatory capacity of the GRACE risk score was evaluated by the area under the receiver operating characteristic [ROC] curve. The primary endpoint was defined as the occurrence of reinfarction and in-hospital mortality, and the secondary endpoint was in-hospital mortality.

A model with an AUC-ROC between 0.8 and 0.9 was considered to have a good capacity for discrimination.

Results

Among the 19.430 patients included in the ProACS between October 2010 and January 2019, we identified 7304 patients with NSTEMI that performed coronary angiogram and had the GRACE score calculated (37.6%). Patients were divided in three groups according to the GRACE score (group 1: 1–108; group 2: 109–140; group 3: 141–372), with 24.9% included in group 1, 33.0% in group 2, and 42.1% in group 3. Most patients were male (73.4%), with a mean age of 66±12 years, and 48.0% were admitted to non-percutaneous coronary intervention centers. In-hospital mortality was 1.0% and the primary endpoint occurred in 2.2% of the patients. The discriminatory capacity of the GRACE score in our population was good regarding in-hospital mortality: the area under the ROC curve was 0.83 (95% confidence interval [CI], 0.783–0.878), with the best cut-off of 148. The discriminatory capacity for the primary end-point was reasonable; the area under the ROC curve was 0.700 (95% CI 0.654–0.745), and the best cut-off was 164.

Conclusions

In our population of patients with NSTEMI submitted to an invasive strategy, the GRACE risk score presented a moderate discriminatory capacity for the occurrence of reinfarction and in-hospital, and a a good discriminatory power for in-hospital mortality.

P5553Right ventricular involvement in hypertrophic cardiomyopathy: insights from a tertiary centre

Introduction

Hypertrophic cardiomyopathy (HCM) is the main cause of sudden cardiac death in the young and a cause of heart failure (HF) and death at any age. Nevertheless, adverse long-term outcomes are not easy to predict.

Objectives

To assess the prevalence and prognostic value of right ventricular (RV) involvement in patients (pts) with HCM.

Methods

Retrospective single-centre study of consecutive pts with HCM evaluated in a specialized consultation. Selected those submitted to cardiac magnetic resonance imaging (CMR) as the gold-standard for RV assessment. The primary endpoint (PE) was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, ventricular arrhythmias with hemodynamic instability and unplanned HF admission.

Results

Of a total of 181 pts, 104 fulfilled the inclusion criteria (mean age at first consultation 62.1±9.7 years, 63.5% male). Septal asymmetric phenotype was the most frequent (73.1%) and 24 pts (23.1%) had rest LV outflow tract obstruction. Mean value of maximum wall thickness was 18.8±4.6 mm. Regarding CMR parameters (Fig A), 5.8% had RV dysfunction and 2.9% RV free wall hypertrophy; no patient presented RV dilation. Late gadolinium enhancement (LGE) of joint points was observed in 47.1%. During follow-up (FU, mean 56.6±29.5 months), survival free of RV dysfunction was 94.3%. Only 5 pts developed RV compromise assessed by echocardiographic parameters: TAPSE 12.0±3.4 mm and pulsed tissue Doppler systolic annular velocity (tricuspid S') wave 7.3±0.9 cm/s. These pts were significantly older (p<0.01) and had higher values of average tissue doppler E/E' ratio at diagnosis (p<0.01). Global RV involvement (at diagnosis or during FU) were associated with increased values of indexed left atrial area (p<0.01), LV dysfunction (p=0.01), LGE of joint points (p=0.01) and higher values of NT-proBNP (p=0.01). In multivariate logistic regression, left atrial enlargement was the only independent predictor of global RV dysfunction (OR 1.9, 95% CI 1.1–3.2, p=0.01) and average E/E' ratio an independent predictor of RV dysfunction during FU (OR 1.3, 95% CI 1.1–1.5, p<0.01). PE rate was 10.6%. It was significantly higher in pts with global RV involvement and there was a significant difference in survival analysis (Fig B). Average E/E' ratio (OR 1.5, 95% CI 1.1–1.9, p=0.01) and RV ejection fraction (OR 0.8, 95% CI 0.7–0.9, p=0.01) were independent predictors of the outcome.

Conclusions

Although not common, RV dysfunction was associated with a higher rate of cardiovascular events. Average E/E' ratio, as a measure of left ventricular filling pressure, was a risk factor for both RV dysfunction and PE. Higher values of RV ejection fraction were protective of adverse events occurrence. Together, these results support a potential role of RV function in the risk stratification of HCM pts.

P3128Unprotected left main revascularization in patients with acute myocardial infarction: insights of a multicenter national registry

Introduction

Unlike stable coronary disease, there is no consensus about the best revascularization strategy for unprotected left main coronary artery (ULMCA) disease associated with acute myocardial infarction (MI). Recent studies have shown that percutaneous coronary intervention (PCI) is technically feasible with acceptable outcomes, making it a reasonable alternative to surgical revascularization (CABG).

Aims

To describe the practice of ULMCA revascularization in MI patients (pts) and its evolution over an 9-year period. To analyze the prognosis of this population and determine the effect of revascularization on outcome.

Methods

Retrospective, multicenter national observational study that included 19 430 MI pts from October 2010 to December 2018. Pts who presented ULMCA as culprit lesion were selected and then compared the subgroup that underwent revascularization by PCI alone versus (vs.) CABG alone. Primary endpoint (PE) was a composite of all-cause death, nonfatal re-MI and nonfatal stroke during hospital stay. Secondary endpoint (SE) was all-cause death rate at 1-year after hospital discharge.

Results

204 pts with ULMCA as culprit lesion were selected (1.1% of all pts): 77.9% male, mean age 69±12 years, 97 (47.5%) underwent CABG alone, 92 (45.1%) PCI alone, 10 (4.9%) no revascularization and 5 (2.5%) both strategies. At admission, pts undergoing PCI alone presented more frequently with ST-segment elevation, persistent chest pain, cardiogenic shock and higher values of GRACE risk score. During hospital stay, severe left ventricular (LV) systolic dysfunction (<30%), need for mechanical ventilation, sustained ventricular tachycardia and aborted cardiac sudden death were also more common in these pts. Concerning PE, global rate was 18.5% (27 deaths, 6 nonfatal re-MI and 2 nonfatal stroke). It was significantly higher in pts undergoing PCI alone (32.6% vs. 3.1%, p<0.01). After adjustment, surgical revascularization had 98% lower odds of PE occurrence compared to PCI (OR 0.02, 95% CI 0.002–0.22, p<0.01). Cardiogenic shock at admission (OR 5.06, 95% CI 1.21–21.11, p=0.03) and severe LV systolic dysfunction (OR 7.77, 95% CI 1.49–40.56, p=0.02) were also independent predictors of adverse outcome. One-year all-cause death rate was 4.9%, with no significant difference at survival curves between PCI vs. CABG (Log-Rank p=0.96).Over the 9-year, there was not a significant change in the use of one revascularization technique over the other.

Conclusions

MI with ULMCA as culprit lesion is infrequent and associated with a high rate of adverse events during hospital stay. PCI was preferred in higher risk pts but, even after adjustment, it was associated with a less favorable short-term outcome compared to surgical strategy. Nevertheless, long-term prognosis was excellent in hospital survivors with no difference between both techniques. Randomized trials are needed to determine the ideal revascularization strategy for these pts.

P3364Cardiac damage in a real-world severe aortic stenosis population

Introduction

The cardiac consequences of aortic stenosis, besides left ventricular ejection fraction and systolic pulmonary artery pressure, aren't considered in the recommendations for surgical intervention in patients (pts) with severe aortic stenosis (SAS). In 2017, a new staging echo classification was presented to accurately describe them.

Purpose

To evaluate this new echo classification in risk stratification of pts with SAS with or without AVR, in a real–world setting.

Methods

Retrospective cohort study of pts with SAS (mean transvalvular pressure gradient (MG) ≥40 mmHg or a peak transvalvular velocity (PTV) ≥4.0 m/s), examined between January 2014 and December 2016. Pts were classified according to the new staging echo classification (no extravalvular cardiac damage - Stage 0, left ventricular damage - Stage 1, left atrial or mitral valve damage - Stage 2, pulmonary vasculature or tricuspid valve damage - Stage 3, or right ventricular damage - Stage 4). Follow-up (FU) was 2.6±1.0 years. The primary outcome was a composite of cardiovascular death or heart failure hospitalization.

Results

212 pts with SAS were included (age 76.1±9.1 years, 31.6% men; aortic valve area 0.69±0.21cm2; PTV 4.5±0.4m/s; MG 48.5±11.6mmHg; LVEF 58.8±12.2%).

19 (9.0%) pts were classified as Stage 0, 29 (13.7%) as Stage 1, 129 (60.8%) as Stage 2, 12 (5.7%) as Stage 3 and 23 (10.8%) as Stage 4.

Pts with more advanced stages had more events (stage 0: 5.3%; stage 1: 10.3%; stage 2: 17.1%; stage 3: 50.0%; stage 4: 52.2%; p<0.0001). In the multivariate analysis, the classification system was also a predictor of the outcome, even when including the AVR in the model (table 1).

Similar findings in the uni and multivariate analysis were identified when analyzing only the pts with SAS and no aortic intervention (events in stage 0: 16.7%; stage 1: 18.2%; stage 2: 29.3%; stage 3: 75.0%; stage 4: 64.7%, p<0.005; Figure 1).

Table 1. Predictors of the outcome Variables Adjusted HR (95% CI) p-value Sex* 1.86 (1.01–3.44) 0.047 eGFR* 0.99 (0.98–1.01) 0.201 AVR* 8.97 (3.85–20.90) 0.0001 Classification* – 0.031   Stage 0 0.19 (0.02–1.537) 0.120   Stage 1 0.28 (0.08–1.01) 0.052   Stage 2 0.36 (0.17–0.74) 0,006   Stage 3 0.81 (0.30–2.19) 0.675   Stage 4 1 – *Variables with p<0.05 in univariate analysis.

Figure 1. Survival of SAS pts with no AVR

Conclusion

In a real-world experience, the new staging echo classification showed a significant relationship between the extent of cardiac damage at baseline and the primary outcome in pts with SAS, even after controlling for AVR. This classification was also able to identify the SAS pts who did not perform AVR and had a significant risk of adverse events.

P6403Predictors of bleeding in elderly patients with myocardial infarction: data from the real world

Background

The population of elderly patients with acute myocardial infarction (MI) is clearly underrepresented in contemporary clinical trials. This population presents a higher risk of both cardiovascular and bleeding events, making the decision of the antithrombotic strategy particularly challenging.

Purpose

To characterize the antithrombotic therapy used in patients with MI and age ≥75 years, and to identify predictors of major bleeding and cardiovascular events in this population.

Methods

Retrospective analysis of patients with a diagnosis of MI and age ≥75 years included in the Portuguese Registry of Acute Coronary Syndromes between October 2010 and January 2018. Logistic regression analysis was used to identify predictors of major bleeding and of the combined endpoint of in-hospital mortality and reinfarction.

Results

The analysis included 17.868 patients of which 30.1% with age ≥75 years. This population had a mean age of 82±5 years, 57% were male and 36% had a diagnosis of STEMI. On admission 10% presented with Killip-Kimball (KK) class III or IV, 14% were on atrial fibrillation (AF), and the mean Hb and creatinine levels were 13±2 g/dl and 1.6±1.2 mg/dl, respectively. In comparison with younger patients, this population had higher Grace and Crusade scores (178 vs 139, and 41 vs 24, respectively). Most elderly patients (74%) underwent coronary angiography (71% by radial artery access) and 75% were submitted to percutaneous revascularization, 9% to surgery, and 1% to an hybrid strategy. Aspirin was used in 96% of patients, clopidogrel in 82%, ticagrelor in 13% (vs 25% of younger patients; p<0.001), and glycoprotein IIb/IIIa inhibitors (GPI) in 11%. Most patients were anticoagulated with enoxaparin (68 vs 56% of younger patients; p<0.001), 22% with unfractionated heparin (vs 30%; p<0.001), and 13% with fondaparinux (vs 14%; p=0.018). Complications were more common in the elderly population, including mechanical complications (1 vs 0.5%), atrioventricular block (5 vs 3%), stroke (1 vs 0.6%), major bleeding (3 vs 1%), in-hospital death (8 vs 2%) and reinfarction (2 vs 1%) (p<0.001 for all).

In multivariate logistic regression analysis, the predictors of major bleeding were diastolic blood pressure (BP) on admission <50 mmHg, maximum creatinine ≥2 mg/dl and the use of GPI. The predictors of the combined endpoint were a diagnosis of STEMI, previous history of cancer, chronic kidney disease or demencia, and the presence on admission of an heart rate <60 bpm, systolic BP <90 mmHg or ≥180 mmHg, KK class > I, AF, left bundle branch block, and left ventricle systolic dysfunction.

Conclusions

This study reflects the contemporary national reality of the management of elderly patients with MI. Overall, this population has a high risk of major bleeding, but several characteristics are associated with an even higher risk, such as the hemodynamic profile, renal function, and the use of GPI.

Antiferromagnetic skyrmions overcoming obstacles in a racetrack

Topological objects interacting with lattice defects is an important topic in condensed matter physics. In this paper, we would like to explore the ballistic trajectory of an antiferromagnetic skyrmion in a racetrack to study processes such as collisions of skyrmions and holes in the magnetic sample. The skyrmion is impelled against the hole-obstacle by means of a spin polarized current. Depending on the skyrmion velocity (associated to the strength of the applied current) and the type of collision (frontal or lateral), it will be captured, scattered or completely destroyed by the hole. In some cases, this obstacle can shift the skyrmion center from a straight line to another one, and it appears as an effective way of manipulating skyrmion trajectories and dynamics.

Approaches to mimic the complexity of the skeletal mesenchymal stem/stromal cell niche in vitro

Mesenchymal stem/stromal cells (MSCs) are an essential element of most modern tissue engineering and regenerative medicine approaches due to their multipotency and immunoregulatory functions. Despite the prospective value of MSCs for the clinics, the stem cells community is questioning their developmental origin, in vivo localization, identification, and regenerative potential after several years of far-reaching research in the field. Although several major progresses have been made in mimicking the complexity of the MSC niche in vitro, there is need for comprehensive studies of fundamental mechanisms triggered by microenvironmental cues before moving to regenerative medicine cell therapy applications. The present comprehensive review extensively discusses the microenvironmental cues that influence MSC phenotype and function in health and disease - including cellular, chemical and physical interactions. The most recent and relevant illustrative examples of novel bioengineering approaches to mimic biological, chemical, and mechanical microenvironmental signals present in the native MSC niche are summarized, with special emphasis on the forefront techniques to achieve bio-chemical complexity and dynamic cultures. In particular, the skeletal MSC niche and applications focusing on the bone regenerative potential of MSC are addressed. The aim of the review was to recognize the limitations of the current MSC niche in vitro models and to identify potential opportunities to fill the bridge between fundamental science and clinical application of MSCs.

Experimental and theoretical evidences for the ice regime in planar artificial spin ices

In this work, we explore a kind of geometrical effect in the thermodynamics of artificial spin ices (ASI). In general, such artificial materials are athermal. Here, We demonstrate that geometrically driven dynamics in ASI can open up the panorama of exploring distinct ground states and thermally magnetic monopole excitations. It is shown that a particular ASI lattice will provide a richer thermodynamics with nanomagnet spins experiencing less restriction to flip precisely in a kind of rhombic lattice. This can be observed by analysis of only three types of rectangular artificial spin ices (RASI). Denoting the horizontal and vertical lattice spacings by [Formula: see text] and [Formula: see text], respectively, then, a RASI material can be described by its aspect ratio [Formula: see text]. The rhombic lattice emerges when [Formula: see text]. So, by comparing the impact of thermal effects on the spin flips in these three appropriate different RASI arrays, it is possible to find a system very close to the ice regime.

Inpatient Dermatology Consultations in Renal Transplant Recipients

BACKGROUND

Renal transplant recipients (RTR), which are an increasing population, frequently suffer from post-transplant dermatological complications. Despite the well-established role of dermatologists in the outpatient care of these patients, no previous studies were found concerning dermatology consultations for hospitalized RTR.

OBJECTIVES

To investigate the epidemiology of dermatological conditions presented by RTR during hospitalization and assess the impact of dermatology consultations performed in the hospital setting.

METHODS

Dermatology consultations requested for RTR admitted at a kidney transplantation referral hospital in Brazil over 36 consecutive months were retrospectively included.

RESULTS

176 consultations were included. Infectious dermatoses prevailed (52.3%), followed by inflammatory diseases (14.2%), neoplasms (12.5%) and drug reactions (8.5%). Diagnostic agreement between requesting and consulting teams was 38.1%. Most consultations were motivated by common dermatological conditions, unrelated to admission diagnosis. There were some differences in comparison to previous studies including general inpatients, such as: larger proportion of infectious dermatoses and neoplasms, smaller proportion of inflammatory diseases, higher percentage of patients submitted to skin biopsy, smaller proportion of consultations managed with a single visit and higher probability of a systemic treatment being recommended in this population.

CONCLUSION

Hospitalized RTR present distinct dermatological epidemiology and higher level of complexity, when compared to studies including general inpatients. Dermatology interventions during hospitalization may be beneficial in the multidisciplinary care of these patients, either contributing to the investigation of systemic conditions or providing relief for cutaneous comorbidities.

Effects of second neighbor interactions on skyrmion lattices in chiral magnets

In this paper we investigate the influences of the second neighbor interactions on a skyrmion lattice in two-dimensional chiral magnets. Such a system contains the exchange and the Dzyaloshinskii-Moriya for the spin interactions and therefore, we analyse three situations: firstly, the second neighbor interaction is present only in the exchange coupling; secondly, it is present only in the Dzyaloshinskii-Moriya coupling. Finally, the second neighbor interactions are present in both exchange and Dzyaloshinskii-Moriya couplings. We show that such effects cause important modifications to the helical and skyrmion phases when an external magnetic field is applied.

Interrelationship Between Organizational and Relational Aspects and the Return-to-Work Process: A Case Study with Nursing Professionals at a Teaching Hospital in Brazil

Introduction The process of returning to work, especially for individuals with labor restrictions, impacts work teams and interferes with the labor reinsertion process. In this study, we aimed to understand the impact of these situations on a nursing team from both organizational and relational perspectives. Methods We conducted a qualitative research study at a university hospital in the municipality of São Paulo using three strategies: documentary analysis; semi-structured interviews with pairs of workers returning to a labor situation; and a focus group with nursing managers. Results Medical leaves of absence overburden the employees who remain working. Regarding the return to work, the participants reported both positive and negative aspects. One positive aspect reported was that those who return to work contribute to the division of labor, generating solidarity and cooperation. The negative aspects reported were related to the return of workers with labor restrictions who do not fully resume their activities, consequently generating conflicts within the work teams that interfere with the reintegration processes. The supervisors reported difficulties reorganizing work on a broad scale and assessing the workers' diagnoses and symptoms and the workers themselves in terms of the necessity of their leaves and the validity of their labor restrictions. Conclusion The organization of labor and social relationships among peers and supervisors is a significant contributor to the success or failure of the work reintegration process and therefore should be considered. We aimed to address this issue by highlighting the complexity of the return-to-work process among health workers.

Investigation of ferromagnetic resonance and magnetoresistance in anti-spin ice structures

In this work, we report experimental and theoretical investigations performed in anti-spin ice structures, composed by square lattice of elongated antidots, patterned in nickel thin film. The magnetic vortex crystal state was obtained by micromagnetic simulation as the ground state magnetization, which arises due to the magnetic stray field at the antidot edges inducing chirality in the magnetization of platters among antidots. Ferromagnetic resonance (FMR) and magnetoresistance (MR) measurements were utilized to investigate the vortex crystal magnetization dynamics and magnetoelectric response. By using FMR, it was possible to detect the spin wave modes and vortex crystal resonance, in good agreement with dynamic micromagnetic simulation results. The vortex crystal magnetization configuration and its response to the external magnetic field, were used to explain the isotropic MR behaviour observed.

Emergence and mobility of monopoles in a unidirectional arrangement of magnetic nanoislands

Magnetricity, the magnetic equivalent of electricity, was recently verified experimentally for the first time. Indeed, like the stream of electric charges that produces electric current, emergent magnetic monopoles have been observed to roam freely in geometrically frustrated magnets known as spin ice. However, such phenomena demand extreme physical conditions, say, a single spin ice crystal has to be cooled to very low temperature, around 0.36 K. Candidates to overcome this difficulty are their artificial analogues, the so-called artificial spin ices. Here, we demonstrate that a specific unidirectional arrangement of nanoislands yields a peculiar system where magnetic monopoles emerge and are constrained to move along aligned dipoles, providing an ordered flow of magnetic charges at room temperature.

Order and thermalized dynamics in Heisenberg-like square and Kagomé spin ices

Thermodynamic properties of a spin ice model on a Kagomé lattice are obtained from dynamic simulations and compared with properties in square lattice spin ice. The model assumes three-component Heisenberg-like dipoles of an array of planar magnetic islands situated on a Kagomé lattice. Ising variables are avoided. The island dipoles interact via long-range dipolar interactions and are restricted in their motion due to local shape anisotropies. We define various order parameters and obtain them and thermodynamic properties from the dynamics of the system via a Langevin equation, solved by the Heun algorithm. Generally, a slow cooling from high to low temperature does not lead to a particular state of order, even for a set of coupling parameters that gives well thermalized states and dynamics. At very low temperature, however, square ice is more likely to reach states near the ground state than Kagomé ice, for the same island coupling parameters.

Magnetic anisotropy of elongated thin ferromagnetic nano-islands for artificial spin ice arrays

The energetics of thin elongated ferromagnetic nano-islands is considered for some different shapes, aspect ratios and applied magnetic field directions. These nano-island particles are important for artificial spin ice materials. For low temperature, the magnetic internal energy of an individual particle is evaluated numerically as a function of the direction of a particle's net magnetization. This leads to estimations of effective anisotropy constants for (1) the easy axis along the particle's long direction, and (2) the hard axis along the particle's thin direction. A spin relaxation algorithm together with fast Fourier transform for the demagnetization field is used to solve the micromagnetics problem for a thin system. The magnetic hysteresis is also found. The results indicate some possibilities for controlling the equilibrium and dynamics in spin ice materials by using different island geometries.

[Children in the Estado Novo: a reading of long duration]

O artigo trata do discurso que justificou a constituição do programa de proteção materno-infantil lançado durante o Estado Novo, em 1940, a partir da criação do Departamento Nacional da Criança. Sustenta-se aqui a idéia de que ele correspondeu a uma leitura conservadora da metáfora dualista, formalizada no século XVIII, que resultou em demonização do adulto e endeusamento da criança. Para tanto, o discurso é remontado em seus elementos fundamentais e comparado com duas interpretações diferentes sobre o mesmo tema, com as quais se defrontou: a proposta de política social do movimento feminista (dos anos 30) e uma análise crítica do sociólogo Guerreiro Ramos. Ao fim, procura-se demonstrar que elementos inscritos na mentalidade coletiva podem ser lidos de maneiras diversas.