Assessment of marine macroalgae potential for gadolinium removal from contaminated aquatic systems

Gadolinium (Gd) is a rare earth associated with hospital and urban wastewaters due to its application as a contrast agent for magnetic resonance imaging. In this work, the uptake of Gd from contaminated seawater by three living marine macroalgae, Ulva lactuca (Chlorophyta), Fucus spiralis (Phaeophyta) and Gracilaria sp. (Rhodophyta) was studied along 72 h. Surface analysis (FTIR), water content, kinetic modelling, and Gd quantification in seawater and biomass were performed. All species were able to accumulate Gd from seawater with 10, 157, and 500 μg Gd L^-1, although green and red macroalgae performed better, following the order: green > red > brown. Removal efficiencies reached 85%, corresponding to a bioconcentration factor of 1700. In more complex solutions that intended to mimic real contaminated environments, namely mixtures with other rare earth elements (Y, La, Ce, Pr, Nd, Eu, Tb, Dy), and with potentially toxic elements commonly found in wastewaters (Cr, Ni, Cu, Cd, Hg, Pb), at two salinities (10 and 30), the macroalgae kept its efficiency: 84% and 88% of removal by green and red macroalgae, respectively. Overall, findings evidence that living macroalgae could be a countermeasure to the increasing anthropogenic enrichment of Gd observed in the aquatic environment.

Epicardial adipose tissue and atrial fibrillation: guilty as charged or guilty by association?

Background

Epicardial adipose tissue (EAT) has been linked to the presence and burden of atrial fibrillation (AF). However, it is still unclear whether this relationship is causal or simply a surrogate marker of other risk factors commonly associated with AF.

Purpose

The purpose of this study was to assess the relationship between these factors and EAT, and to compare their performance in predicting AF recurrence after an ablation procedure.

Methods

We assessed 575 consecutive patients (mean age 61±11 years, 62% male) undergoing AF ablation preceded by cardiac CT in a high-volume ablation center. EAT was measured on cardiac CT using a modified simplified method. Patients were divided into 2 groups (above vs. below the median EAT volume). Cox regression was used to assess the relationship between epicardial fat, risk factors, and AF relapse.

Results

Patients with above-median EAT volume were older (p<0.001), more often male (OR 1.7, p=0.002), had higher body mass index, and higher prevalence of smoking, hypertension, diabetes and dyslipidemia (p<0.05). Non-paroxysmal AF was also more common in those with above-median EAT volume. During a median follow-up of 18 months, 232 patients (40.3%) suffered AF recurrence. After adjustment for BMI and other univariate predictors of relapse, three variables emerged independently associated with time to AF recurrence: non-paroxysmal AF (HR 2.1, 95% CI: 1.5–2.7, p<0.001), indexed left atrial (LA) volume (HR 1.006 per mL/m2, 95% CI: 1.002–1.011, p<0.001), and indexed epicardial fat volume (HR 1.87 per mL/m2, 95% CI: 1.66–2.1, p<0.001). None of the classic cardiovascular risk factors were an independent predictor of AF recurrence (all p>0.10).

Conclusion

Classic cardiovascular risk factors are more prevalent in patients with higher amounts of epicardial fat. However, unlike these risk factors, EAT is a powerful predictor of AF recurrence after ablation. These findings suggest that EAT is not merely a surrogate marker, but an important participant in the pathophysiology of AF.

EAT, cvrf and AF burden

Funding Acknowledgement

Type of funding source: None

Inconsistent effects of gluten on obesity: is there a role for the haptoglobin isoforms?

BACKGROUND AND AIMS

There is no clear evidence about the effects of gluten intake on obesity. It is known that gluten's effects on gut permeability are mediated by zonulin, a protein identified as pre-haptoglobin 2, a physiological regulator of the intestinal barrier. We investigated the obesogenic and inflammatory effects of gluten and its association with the haptoglobin genotype.

METHODS

This was a single blinded, crossover study, including 40 overweight or obesity women free of celiac disease. Participants adopted a gluten-free diet (GFD) for 8 weeks and consumed a gluten-free muffin (GF-M) or a gluten-containing muffin (GLU-M, 24 g gluten) for 4 weeks, switching muffin type during the subsequent 4 weeks. During a follow-up period of 4 weeks we evaluated the usual diet (UD). Food diaries were collected to estimate the macronutrient intake and dietary inflammatory index (DII®). Bodyweight and composition, resting energy expenditure (REE), and cytokines were assessed. Haptoglobin alleles (Hp1 and Hp2) were genotyped to characterize zonulin expression.

RESULTS

Energy and macronutrient intakes were similar during both periods, except for protein intake, which was higher during GLU-M. DII scores indicated a more inflammatory profile during the GF-M and GLU-M periods compared to UD. No differences were observed in body composition or REE between interventions when the Hp genotype was not considered. Nonetheless, those carrying the Hp2-2 genotype (overexpressing zonulin) presented lower REE and higher levels of IL6 and IL1beta only during gluten intake (GLU-M and UD) compared to age- and body mass index-matched Hp1-1 carrier. These results suggest an obesogenic and inflammatory action of gluten only in those overexpressing zonulin (Hp2-2).

CONCLUSION

These results highlight the importance of zonulin as the mediator of gluten obesogenic and inflammatory effects. Our data suggest that in the presence of gluten, zonulin release is associated with a reduction of REE and an increase of inflammatory markers that are not seen in zonulin low producers.

Unveiling coronary inflammation by perivascular fat angio-CT: a propensity-matched score analysis

Background

Inflammation plays a pivotal role in the atherogenic process and recently has been the target of successful clinical trials. A new CT angiography method allows the identification of inflammatory pericoronary fat, which is associated with cardiovascular events. We aimed to determine whether patients with obstructive coronary artery disease (CAD) have a higher pericoronary inflammatory milieu when compared to those without CAD.

Methods

From a prospective CT angiography registry of patients with suspected obstructive CAD, those with a luminal stenosis >70% confirmed by invasive coronary angiography were screened (previous coronary artery bypass grafting was an exclusion criteria). Subsequently, we applied a 1:1 propensity score (PS) without replacement protocol to match obstructive CAD patients with those without CAD (non-CAD), using age, gender, BMI, hypertension, dyslipidemia, diabetes and smoking status as covariates. Similar to previous reports, pericoronary fat characterization by CT angiography was performed by analyzing the fat attenuation index (FAI) at the −30 to −190 HU range. Inflammatory fat was defined by a FAI >−70 HU. The proximal 50mm of the right coronary artery (RCA) was used to perform fat quantification and characterization. The perivascular fat was defined as the adipose tissue within a radial distance from the outer vessel wall equal to the diameter of the vessel.

Results

A matched cohort of 48 patients was identified (mean age 63 years; 77% males) – 24 obstructive CAD and 24 non-CAD patients. Mean FAI was numerically higher in obstructive CAD compared to the non-CAD cohort (−74±7 vs −78±7; p=0.083). Although not statistically significant, those with obstructive CAD had an increased proportion of inflammatory fat (51±10 vs 46±10%; p=0.107). After adjustment for body surface area (BSA), differences in the inflammatory fat proportion became apparent between obstructive CAD and non-CAD patients (28±6 vs 24±5%/m2; p=0.024). Furthermore, we observed a significant correlation between the inflammatory fat proportion (both absolute value and BSA adjusted) and the total number of RCA plaques (r=0.458; p=0.003; and r=0.451; p=0.003, respectively). Finally, there was 1 additional plaque observed in the RCA for each increase in 10% of proportion of inflammatory fat (p=0.018).

Conclusions

Perivascular coronary inflammation, as measured by FAI, seems significantly heightened in patients with obstructive CAD compared to a matched cohort of non-CAD patients. Further studies are needed to ascertain the mechanisms and possible implications of this association.

Funding Acknowledgement

Type of funding source: None

Predicting pacemaker implantation after TAVR with procedural CT

Background and aim

The need for permanent pacemaker implantation (PPMI) is a burdensome complication of transcatheter aortic valve replacement (TAVR). Calcium distribution in the aortic-valvular complex (AVC) and, more recently, membranous septum (MS) length seem to be surrogate markers for conduction abnormalities after specific last generation balloon and self-expandable expandable valves. We sough to evaluate whether such pre-procedural association remains across the entire device spectrum.

Methods

Single-centre prospective study of 239 consecutive patients (140 women, median age of 84) with severe symptomatic aortic stenosis patients who underwent ECG-gated contrast-enhanced multi-detector computed tomography (MSCT) before TAVR since Jun/2017. Exclusion criteria were those with previous PPMI, previous bioprothesis, congenital bicuspid valve, and poor imaging quality. The J-score with an 850-Hounsfield unit threshold was used to detect areas of calcium in the region of interest. AVC was characterized by leaflet sector and region, using 3mensio Valves software 7.0 TM. An independent team retrospectively measured MS length blindly by determining the thinnest part of the interventricular septum in the coronal view in the better-defined systolic phase (usually at 40% of the R-R interval, Figure). Device selection (75.8% self-expandable devices, 20.1% balloon expandable, 3.1% other) and positioning were performed according to the operator criteria. Final implant depth was assessed based on the pre-release angiogram or final aortography.

Results

Mortality at 30-days was 1.3% and PPMI occurred in 43 patients (18%). Median MS length was 9.59mm (IQR: 3.11mm). After multivariable logistic regression analysis, MS length emerged as the single significant protective predictor for PPMI (OR: 0.14; 95% 95% CI: 0.05–0.42; p<0.001), independently of the device used (p<0.001). MS length showed strong discriminatory ability for PPMI (c-statistic 0.93; 95% CI 0.88–0.99). Sensitivity/specificity decision plots yielded an MS length of 6.9 mm as the optimal cut-off point for predicting the need for PPMI with a positive and negative predictive value of 91% and 93%, respectively (Figure). There wasn't any calcium accumulation within a specific region of AVC that independently predicted the outcome.

Conclusion

In our experience, a short membranous septum was strongly and independently associated with new permanent pacemaker implantation, regardless of the device type.

Our findings suggest that this simple measure should be routinely made to help device selection and implantation technique.

Funding Acknowledgement

Type of funding source: None

Lung water quantification by cardiac magnetic resonance imaging: a novel prognostic tool in hf

Background

Cardiac magnetic resonance (CMR) imaging has recently been proposed to quantify lung water density (LWD, %) non-invasively. Given that pulmonary congestion plays a key role in the pathophysiology of Heart Failure (HF), we designed a study to assess the prognostic significance of a simplified LWD measure in patients with HF and reduced left ventricular ejection fraction (LVEF).

Methods

We conducted a single-center retrospective study of consecutive patients with HF and LVEF <50% who underwent CMR on a 1.5T scanner. Those with severe interstitial lung disease or chronic liver disease were excluded. All measurements were performed in a parasagittal plane at the right midclavicular line on a standard HASTE sequence, which is widely available in all CMR studies. As previously reported, LWD was determined by the lung-to-liver signal ratio multiplied by 0.7. A cohort of 102 healthy controls was used to derive the upper limit of normal (mean ± 2SD) of the LWD (21.2%). The primary endpoint was a composite of all-cause death or HF hospitalization.

Results

A total of 290 HF patients (mean age 64±12 years, 74.8% male, 56.2% of ischemic etiology) with a mean LVEF of 34±10% were included. LWD measurement took on average 35±4 seconds and showed excellent inter-observer agreement (intra-class correlation coefficient >0.90). LWD was increased in 65 (22.4%) patients. Compared to those with normal LWD, the former were more symptomatic (NYHA ≥III: 29.2% vs. 1.8%; p=0.017) and had higher median NT-proBNP [1973 (IQR: 809–3766) vs 802 (IQR: 355–2157pg/mL); p<0.001]. During a median followup of 21 months (IQR: 13–29), 20 (6.9%) patients died and 40 (13.8%) had at least one HF hospitalization. In multivariate analysis, LVEF (HR per 1%: 0.96; CI-95%: 0.93–0.99; p=0.024), creatinine (HR per 1mg/dL: 2.43; CI-95%: 1.25–4.71; p=0.009) and LWD (HR per 1%: 1.06; CI-95%: 1.01–1.12; p=0.013) were independent predictors of the primary endpoint. The findings were mainly driven by an association between LWD and HF hospitalization (HR per 1%: 1.08; CI-95%: 1.03–1.13; p=0.002).

Conclusions

A CMR-derived method for LWD quantification independently predicts an increased risk of death or HF hospitalization in HF patients with LVEF <50%. Our results support LWD measurement as a simple, reproducible and widely available method, further adding to the prognostic role of CMR in this population.

Funding Acknowledgement

Type of funding source: None

Relationship between epicardial fat and left atrium fibrosis in patients with atrial fibrillation

Background

Epicardial adipose tissue (EAT) has recently been shown to be associated with the presence, severity, and recurrence of atrial fibrillation (AF). Although the pathophysiological mechanisms underlying this association remain to be established, several hypotheses have been put forward, including direct adipocyte infiltration, oxidative stress, and the secretion of adipokines causing inflammation and fibrosis of atrial tissue. We hypothesized that the volume of EAT and the amount of left atrium (LA) fibrosis assessed by non-invasive imaging would be significantly correlated in patients with AF, and that both would predict time to relapse after pulmonary vein isolation (PVI).

Methods

Sixty-eight patients with AF being studied for a first PVI procedure underwent both cardiac computerized tomography (CT) and cardiac magnetic resonance (CMR) within less than 48h. EAT was quantified on contrast-enhanced CT images. LA fibrosis was quantified on isotropic 1.5mm 3D delayed enhancement CMR for image intensity ratio values >1.20. Radiofrequency PVI was performed using an irrigated contact force-sensing ablation catheter, guided by electroanatomical mapping. After PVI, patients were followed for AF recurrence, defined as symptomatic or documented AF after a 3-month blanking period. Pearson's correlation coefficient was used for gauging the correlation between EATLM volume and LA fibrosis. The relationship between these two variables and time to AF recurrence was assessed by Cox regression.

Results

Most of the 68 patients (46 men, mean age 61±12 years) had paroxysmal AF (71%, n=48). The mean body mass index (BMI) was 28.0±4.0 kg/m2. Patients had a median EATLM volume of 2.4 cm3/m2 [interquartile range (IQR) 1.6–3.2 cm3/m2], and a median estimated amount of LA fibrosis of 8.9 g (IQR 5–15 g), corresponding to 8% (IQR 5–11%) of the total LA wall mass. The correlation between EATLM and LA fibrosis was statistically significant but weak (Pearson's R = 0.38, P=0.001) – Figure 1. During a median follow-up of 22 months (IQR 12–31), 31 patients (46%) suffered AF recurrence. Four predictors of relapse were identified in univariate Cox regression: EATLM (HR 2.19, 95% CI 1.65–2.91, P<0.001), LA fibrosis (HR 1.05, 95% CI 1.01–1.09, P=0.033), non-paroxysmal AF (HR 3.36, 95% CI 1.64–6.87, P=0.001), and LA volume (HR 1.03, 95% CI 1.01–1.06, P=0.006). Multivariate analysis yielded two independent predictors of time to AF relapse: EATLM (HR 2.05, 95% CI 1.51–2.79, P<0.001), and non-paroxysmal AF (HR 2.36, 95% CI 1.08–5.16, P=0.031).

Conclusion

The weak correlation between EAT and LA suggests that LA fibrosis is not the main mechanism by which EAT and AF are linked. EAT was more strongly associated with AF recurrence than LA fibrosis, which supports the existence of other, more important mediators between EAT and this arrhythmia.

Correlation between EAT and LA

Funding Acknowledgement

Type of funding source: None

Downstream testing after an halted coronary CT angiography due to high coronary artery calcium score

Background and aim

In many centers, coronary artery calcium score (CACS) is performed immediately before coronary CT angiography (CCTA) in order to exclude heavy calcification that could hamper test performance. When high CACS values are found, CCTA is usually aborted and other tests suggested. However, there are no recommendations on which test to pursue, and little data on their diagnostic yield in this setting. The aim of this study was to assess the type and results of downstream testing among patients whose CCTA study was halted due to high CACS.

Methods

Single-centre retrospective study of consecutive patients undergoing CCTA for suspected obstructive coronary artery disease (CAD). A CACS threshold of >400 was generally used to cancel CCTA. Downstream testing and its results were assessed using electronic medical records. A group of consecutive patients with CACS <400 who underwent CCTA was used for comparison.

Results

Of the 795 patients who performed CCTA for suspected CAD, 86 (10.8%), had their test halted due to high CACS (57 men, mean age 71±11 years). In this subgroup, the median pre-test probability for CAD was 27% (interquartile range 25) and the median CACS was 983 (interquartile range 930). Compared to patients who underwent CCTA, those who saw their tests cancelled were older, more frequently male, and had higher prevalence of cardiovascular risk factors and higher pre-test probability for CAD.

Patient's downstream testing is illustrated in Figure. From the 86 patients enrolled, 12 are currently waiting for downstream tests and were excluded from further analysis. Overall, 35 patients ended up performing invasive coronary angiography (ICA, 47.3%) of whom 19 (54.3%) had significant CAD. Among those who underwent non-invasive testing (N=19, 25.7%), 10 (52.6%) had significant ischemia and 4 (21%) underwent additional testing with ICA. In 24 patients (32.4%), no downstream testing was pursued. Finally, 17 (22.3%) patients underwent coronary revascularization, either percutaneous (N=10, 13.5%) or surgical (N=7, 10.8%).

Conclusion

Invasive coronary angiography is the most frequently used downstream test when CCTA is halted due to high CACS values, and shows significant CAD in roughly half of the cases. Considering the high prevalence of significant CAD, direct referral for ICA (with the possibility of invasive functional testing) seems a reasonable approach.

Funding Acknowledgement

Type of funding source: None

Catheter ablation in atrial fibrillation: comorbidities and mortality from high-volume centers

Background

Catheter ablation (CA), has gained wider acceptance as an attractive option for treating symptomatic AF. Although traditionally seen as a safe procedure, there is limited and conflicting data on procedure-related early morbimortality, with new evidence suggesting early mortality may be as high as 0.5%-1%.

Purpose

We aimed to assess the rates of early and late morbimortality of post-atrial fibrillation (AF) ablation in high-volume centers.

Methods

Prospective registry of 2 high-volume ablation centers, comprising 3722 consecutive patients (mean age 61.1±11.2, 66.4% male, n=2471), who underwent AF ablation from 2005 to 2019. Early mortality was defined as death during initial admission or during the first 45 days after ablation. Median follow-up time was 5.4 years.

Results

Most patients were treated with radiofrequency (97%) while 3% were treated with cryoablation. Early mortality was 0.08% (n=3), with a median time from ablation to death of 22 days. Cumulative mortality at 3, 6 and 12 months was 0.08%, 0.16% and 0.19%, respectively. At 3 and 5 years, mortality remained low at 0.48% and 0.73%, respectively. Early mortality was higher among patients who had suffered procedural complications (fistula and stroke, p<0.001). Among the latter, pericardial effusion and tamponade were the most frequently found (0.6%, n=24), only 1 of which required emergent surgical drainage and myocardial repair. Early ischemic stroke occurred in 2 patients (0.1%). Other less frequent complications were atrio-esophageal fistula (0.1%, n=2), phrenic nerve palsy (0.1%, n=2), anoxic encephalopathy following cardiac arrest (0.03%, n=1) and pulmonary vein stenosis (0.03%, n=1).

Conclusion

Early mortality following ablation is very low (<0.1%), when performed by an experienced high-volume team. Severe complications are rare (<1%) and mostly amenable to treatment. Our findings reaffirm the overall safety of AF ablation.

AF catheter ablation morbimort

Funding Acknowledgement

Type of funding source: None

Pre-test probability of obstructive coronary artery disease in the new guidelines: too much, too little or just enough?

Background

Previous 2013 ESC guidelines recommended the use of the Modified Diamond-Forrester method to assess the pre-test probability (PTP) of obstructive coronary artery disease (CAD). The 2019 ESC Chronic Coronary Syndrome guidelines updated this recommendation with a major downgrade in PTP. The aim of this study was to compare the performance of these two methods in patients with stable chest pain undergoing coronary computed tomography angiography (CCTA) for suspected CAD.

Methods

We performed a retrospective analysis on prospectively collected data from a cohort of consecutive patients undergoing CCTA for suspected CAD from October 2016 to 2019. Key exclusion criteria were age <30 years-old, known CAD, suspected acute coronary syndrome or symptoms other than chest pain. Obstructive CAD was defined as any luminal stenosis ≥50% on CCTA. Whenever invasive coronary angiography (ICA) was subsequently performed, patients were reclassified if luminal stenosis was <50%. The two PTP prediction models were assessed for calibration and discrimination.

Results

A total of 320 patients (median age 63 years [IQR 53–70], 59% women) were included. Chest pain characteristics were: 48% atypical angina, 38% non-anginal chest pain, 14% typical angina. The observed prevalence of obstructive CAD was 16.3% (n=52). Patients with obstructive CAD were more often male, were significantly older and had a higher prevalence of typical angina and cardiovascular risk factors (except for family history of CAD). On average, individual PTP was 22.1% lower in the new guidelines. The 2013 prediction model significantly overestimated the likelihood of obstructive CAD (mean PTP 37.3% vs 16.3%; relative overestimation of 130%, p-value for miscalibration 0.005). The updated 2019 method showed good calibration for predicting the likelihood of obstructive CAD (mean PTP 15.2% vs 16.3%; relative underestimation of 6.5%, p-value for miscalibration 0.712). The two approaches showed similar discriminative power, with a C-statistics of 0.730 and 0.735 for the 2013 and 2019 methods, respectively (p-value for comparison 0.933). Stratification by gender produced similar results.

Conclusions

In patients with stable chest pain undergoing CCTA, the updated 2019 prediction model allows for a more precise estimation of pre-test probabilities of obstructive CAD than the previous model. Adoption of this new score may improve disease prediction and change the downstream diagnostic pathway in a significant proportion of cases.

Graph 1

Funding Acknowledgement

Type of funding source: None

Relative apical sparing in patients with severe aortic stenosis: prevalence and significance

 

Relative apical sparing (RAS) of LV longitudinal strain (LS) is a red flag for diagnostic suspicion of amyloid cardiomyopathy (AC). However, it may present in pts with aortic stenosis (AS), where the prevalence of transthyretin AC is being increasingly reported.

Aim

To describe the prevalence of RAS deformation pattern in patients with AS and its clinical significance.

Methods

We prospectively studied 53 pts (71±8y, 54.7% men) with severe symptomatic AS - mean gradient (AVM): 54.6 mmHg; aortic valve area 0.74cm2, referred for surgical replacement with no previous history of ischemic cardiomyopathy. Beyond ECG and transthoracic echo (TTE), all pts underwent CMR, with tissue characterization before surgery. RAS was defined as average apical LS / average basal LS + average mid LS >1 at 2D LV LS analysis. Aortic valve replacement and septal myocardial biopsy were already performed in 26 pts. AS severity indexes, LV remodelling and tissue characterization were compared in both groups, with and without RAS.

Results

RAS was present in 16 pts (30.8%). There were neither pseudoinfarct pattern or low voltage at ECG, nor infiltration suspicion from CMR study (native T1 value 1047ms [IQR 1028–1084]; ECV 22% [IQR 18–25]). Furthermore, none of the pts had suspicion of amyloid deposition at histopathology. Median CMR LVEF was 64.5% [IQR 51.3–70.8%] and 36 pts (67.9%) had non-ischemic DE, with a median fraction of 6.0% [IQR 4.9–12.7%] of LV mass. Comparing both groups, RAS cohort showed a significantly higher AVM, relative wall thickness, maximum septal thickness, peak systolic dispersion and higher LV indexed mass, DE and lower LVEF at CMR. RAS group has also higher NT pro BNP (Table).

Conclusions

RAS is common in this group of pts despite the absence of clinical and histological signs of myocardial infiltration. RAS occurs with worse indexes of LV remodeling and fibrosis consistent with a more advanced stage of the disease.

Funding Acknowledgement

Type of funding source: None

Epicardial adipose tissue: the genetics behind an emerging cardiovascular marker

Background

Increasing evidence points epicardial adipose tissue (EAT) as an emerging cardiovascular risk marker. Whether genetic polymorphisms are associated with a higher EAT burden is still unknow. Genetic risk score (GRS) is an emerging method that attempts to establish correlation between single nucleotide polymorphisms (SNPs) and clinical phenotypes.

Aim

Evaluate the role of genetic burden and its association to EAT.

Methods

996 patients (mean age 59±8, 78% male) were prospectively enrolled in a single center. EAT was measured on cardiac CT using a modified simplified method. Patients were divided into 2 groups (above vs. below the median EAT volume).

We studied different polymorphisms across the following gene-regulated pathways: oxidation, renin-angiotensin system, cellular, diabetes/obesity and dyslipidemia pathways. Genotyping was performed by TaqMan allelic discrimination assay. A multiplicative genetic risk score (mGRS) was constructed and represents the genetic burden of the different polymorphisms studied. To evaluate the relation between genetics and EAT volume, we compared both groups by: global mGRS, gene cluster/axis mGRS and individual SNPs.

Results

Patients with above-median EAT volume were older, had higher body mass index (BMI) and higher prevalence of hypertension, diabetes and dyslipidemia (p<0.05). Patients with higher EAT volumes presented a higher global mean GRS (p<0.001), with the latter remaining an independent predictor for higher EAT volumes (OR 1.3, 95% CI 1.2–1.5), alongside age and BMI.

In the analysis by gene clusters, patients with more epicardial fat consistently presented a higher polymorphism burden (translated by a higher mGRS level) across numerous pathways: oxidation, renin-angiotensin system, cellular, diabetes/obesity and dyslipidemia. After adjusting for confounders and other univariate predictors of higher fat volume, the following have emerged as independently related to higher EAT volumes: mGRS comprising the genes of different clusters, age and BMI.

Amongst the 33 genes analyzed, only MTHFR677 polymorphisms (a gene with a critical role in regulating plasma homocysteine levels) emerged as significantly related to higher EAT volumes in our population (OR 1.4, 95% CI: 1.100–1.684, p=0.005).

Conclusion

Patients with a higher polymorphism burden in genes involved in the oxidation, renin-angiotensin, cellular, diabetes/obesity and dyslipidemia pathways present higher levels of epicardial fat. This potential association seems to be independent from the expected association between epicardial fat and cardiovascular risk factors. To our knowledge, this is the first time such genetic profiling has been done, casting further insight into this complex matter.

Funding Acknowledgement

Type of funding source: None

LV replacement fibrosis in aortic stenosis: prevalence and relation to LV remodelling and function

Background

Progressive myocardial fibrosis takes part in left ventricular (LV) remodeling in aortic stenosis (AS) and drives the transition from hypertrophy to heart failure. Replacement fibrosis may be characterized by late gadolinium enhancement (LGE) in cardiac magnetic resonance (CMR).

Aim

To assess the prevalence and association between LGE and indexes of LV function in patients with severe aortic stenosis.

Methods

We prospectively studied 53 consecutive patients (age: 71±8 years [min. 51–max. 84], 54.7% men) with severe symptomatic AS, referred for surgical aortic valve replacement with no previous history of ischemic cardiomyopathy. Aortic valve mean gradient was 54.6 mmHg [IQR 46.6–63.2] and aortic valve area 0.74cm2 [IQR 0.61–0.89]; all patients with high gradient, 4 with low-flow. CMR with tissue characterization (T1 mapping, LGE and extracellular volume by ECV quantification – using 5SD from remote myocardium as signal intensity cut-off), was performed before surgery. AS severity indexes, LV mass, systolic and diastolic LV function indexes including global longitudinal strain (GLS) and torsion were compared in both groups of patients, with and without LGE.

Results

Mid-wall LGE was present in 36 patients (67.9%) with a median fraction of 6.0% [IQR 4.9–12.7%] of LV mass. Native T1 value and ECV were within normal ranges (median values: 1047ms [IQR 1028–1084]; 22% [IQR 18–25], respectively). Median CMR LV ejection fraction and mass were 64.5% [IQR 51.3–70.8%] (11 patients with reduced EF) and 76.5g/m2 [IQR 57.4–94.8g/m2], respectively. Median GLS was −13.9% [IQR −11.4 to −17.0%] and torsion was 24.2° [IQR 19.8–32.5°]. Patients with LGE had significantly higher LV mass (87.1g/m2 vs 63.3 g/m2, p=0.001), worse GLS (−14.4% vs −16.9%, p=0.041) and higher NT-proBNP values (1333.7ng/mL vs 559.9ng/mL, p=0.004) (Figure).

Conclusions

Non-ischemic LGE is common in this group of patients with severe symptomatic high gradient aortic stenosis. As it is more prevalent in patients with more pronounced LVH, lower longitudinal deformation and higher NT-proBNP values, it probably represents a more advanced stage of the disease.

Funding Acknowledgement

Type of funding source: None

Disproportionate functional mitral regurgitation: clinical validation of a new conceptual framework

Background

Disproportionate functional mitral regurgitation (FMR) is a novel concept that tries to identify hemodynamically significant FMR by readjusting the effective regurgitant orifice area (EROA) and regurgitant volume (RegVol) cut-offs according to left ventricular end-diastolic volume (LVEDV) and left ventricular ejection fraction (LVEF). However, this theoretical concept lacks clinical validation. The aim of this study was to assess the clinical significance of disproportionate FMR.

Methods

Patients with at least mild FMR and reduced LVEF (<50%) who underwent transthoracic echocardiography between 2010 and 2014 were retrospectively identified in our laboratory database. Optimal medical therapy (including cardiac resynchronization when indicated) for ≥3 months was a prerequisite for inclusion. Hemodynamically significant FMR was defined as regurgitant fraction >50% and the patient-specific theoretical RegVol cut-off was calculated according to the formula presented in Fig. 1a. The difference between the estimated RegVol by the PISA method and the theoretical RegVol cut-off was considered to represent the haemodynamic burden of MR. The primary endpoint was all-cause death. Patients were censured if mitral intervention or heart transplant was undertaken. Survival analysis was used to assess the effect of disproportionate FMR on mortality in 2 subgroups (LVEF <30% and 30–49%).

Results

A total of 289 patients (median age 69 years [IQR 60–77], 75% male, 53% of ischemic aetiology) were included. More than 90% were on beta-blockers and renin-angiotensin inhibitors, 44% on aldosterone receptor antagonists, and 73% had implanted devices. The median LVEF and LVEDV were 34% (IQR 27–41) and 170mL (IQR 128–220), respectively. Median EROA was 10mm2 (IQR 3–21) and RegVol was 15 mL (IQR 4–30). RegVol distribution across the cohort was: <10mL: 41%; 10–20mL: 18%; 20–30mL: 15% and >30mL: 26%. Disproportionate FMR was present in 83 patients (29%). These patients had significantly higher SPAP values (41mmHg [IQR 33–50] vs. 33mmHg [IQR 29–40]; p<0.001).

During a median follow-up of 44 months (IQR 19–73), 106 patients died. In the LVEF <30% subgroup, age (HR 1.05 per year [1.02–1.08]; p<0.001), LVEF (HR 0.94 per 1% [0.89–0.99]; p=0.042) and TAPSE (HR 0.92 per mm [0.86–0.99]; p=0.030) were independent predictors of mortality. In the LVEF 30–49% subgroup, age (HR 1.05 per year [1.02–1.08]; p=0.003), LVEF (HR 0.94 per 1% [0.89–0.99]; p=0.020) and disproportionate FMR (HR 1.02 per mL [1.01–1.03]; p=0.01) were independently associated with increased mortality.

Conclusions

Disproportionate FMR proved to be an important independent predictor of mortality in patients with LVEF between 30–49%. These findings were not replicated in those with LVEF<30%, where the degree of biventricular dysfunction seems to outweigh all other echocardiographic parameters, leaving FMR as a bystander.

Figure 1

Funding Acknowledgement

Type of funding source: None

A kiss or a handshake?! Overview for a deep approach

The way we greet each other is often a source of controversy when it comes to microorganisms transmitted. The goal of this research is to give us a comparison of the quantity and type of microorganisms transmitted between a handshake and kisses on the face, first verifying which of these forms transmits more microbiological beings, and subsequently compare the results with the answers given to a questionnaire on hand and face hygiene. With a sample of 23 Portuguese people, without any skin pathology, the sampling type was probabilistic and the sampling technique was simple random. The technique used was through contact plates, containing an enriched medium (TSA), for each individual, a sample was collected by each route - face and hands. First, the microorganisms present in each pathway were counted, and then identified. The average in the face is 75.2 CFU, while in the hands it is 53.9 CFU, thus there is a significant difference between the two. A questionnaire was also used with questions related to hand and face washing. Regarding the count of CFU's on the plates, there was a higher number of microorganisms in the plates used in the face than in the hand. There is a difference between the amount of microorganisms present in the face and palm of the hands, and the first one has a higher score. This difference can be justified by the fact that we wash our hands more often throughout the day relative to the face. Regarding the type of microorganisms found, the vast majority were Staphylococcus spp and Micrococcus. In some of the plaques were present yeast and fungi, and, in smaller quantity, bacilli. To change these values, a good dissemination of information concerning the proliferation of bacteria, viruses and fungi is essential, as well as the dangers they represent. It is important to be aware of the importance of good hygiene of the skin, as a form of protection itself, but also collective, thus contributing to better public health.

Key messages

Need for good hand and face hygiene. Imperative to conduct more and deep studies about this issue.

Level of literacy and clinical outcomes in patients with Chagas disease: SaMi-Trop project

Background

Chagas disease (CD) is a neglected tropical disease that affects mainly vulnerable population, whose majority has low ability to understand health information. This study aimed to assess the prevalence of health literacy (HL) and its association with sociodemographic, quality of life, health care aspects and worse clinical outcomes.

Methods

This is a cross-sectional study developed inside a cohort study (SaMi-Trop) including 1959 patients. It has been conducted in an endemic region to CD in Brazil. The eligible criteria for HL evaluation was the ability to read. The HL was assessed with SALPHA-18 scale and literacy was categorized in inadequate HL; adequate HL and; illiterate. Multiple models were adjusted using binary logistic regression, multinomial and beta regression models using the gamlss framework.

Results

Of the patients included, 1136 (74.1%) are illiterate. For HL assessment, only 397 managed to complete the HL evaluation. The prevalence of inadequate HL was 85.1% (338), only 59 patients (14.9%) had adequate HL. Our results are as following: 1) being illiterate increases the chance of using more drugs when compared to individuals with adequate HL - 1 or 2 drugs (OR: 1.96; CI: 1.06-3.62) and 3 to 4 medications (OR: 3.06; CI:1.44-6.52), to have hypertension (OR: 2.24; CI: 1.29-3.90), report an average self-perceived health (OR: 2.97; IC: 1.63-5.42) and report poor self-perceived health (OR: 3.67; CI: 1.71-7.89); 2) inadequate literacy increases the chance of using 3 to 4 medications (OR: 2.26; CI: 1.04-4.93) and report an average self-perceived health (OR: 2.48; CI: 1.34-4.62); 3) Illiterate patients present worst quality of life scores in Physical (OR: 0,730; CI: 0,583-0,914), Psychological (OR: 0,671; CI: 0,544-0,828) and Environmental (OR: 0,727; CI: 0,601-0,880) domains.

Conclusions

We found a high prevalence of inadequate HL; it was associated with worse clinical outcomes and poor self-perceived health.

Key messages

Our findings reinforce the importance of improving health communication in CD patients seeking to avoid unfavorable outcomes. A high prevalence of inadequate health literacy was observed in our study, which can impact the self-care ability of patients with CD.

Molecular Sensitization Profile to Dermatophagoides pteronyssinus Dust Mite in Portugal

OBJECTIVE

To analyze component resolved diagnosis to Dermatophagoides pteronyssinus (Der p) in patients with respiratory allergy and its relationship with clinical severity in different geographical areas.

METHODS

217 patients (mean age 25.85±12.7 years; 51.16% females) were included, selected from 13 centers in Portugal (5 from North, n=65). All had allergic rhinitis, with or without asthma, and had positive skin prick tests to at least one dust mite. Specific IgE (sIgE) to Der p, Dermatophagoides farinae, Lepidoglyphus destructor, Der p1, Der p 2, Der p 10 and Der p 23 were determined by ImmunoCAP. Statistical analysis (Mann Whitney U test) compared patients with rhinitis vs rhinitis and asthma; mild vsmoderate-to-severe rhinitis; North vs South.

RESULTS

Prevalence of sensitization was 98.2% to Der p, and 72.4%, 89.4%, 9.7% and 77% to Der p 1, Der p 2, Der p 10 and Der p 23, respectively. Corresponding median sIgE levelswere 8.56, 17.7, 0.01 and 3.95 kUA/L. sIgE to all allergens was higher in patients with moderate-to-severe rhinitis and rhinitis with asthma but not statistically significant (NSS). sIgE to Der p 2 was significantly higher in the South when compared with the North (p=0.0496).

CONCLUSIONS

sensitization to Der p is the most common in Portugal. Der p 2 had the highest prevalence and median sIgE levels. All sIgE to molecular components were higher in more symptomatic patients (NSS). sIgE to Der p 2 was higher in the South, which may be related to the warmer temperature and/or the larger sample size.

Influence of prenatal exposure to dexamethasone on neurodevelopmental behaviour

Introduction Early life stress, such as prenatal exposure to exogenous glucocorticoids (GC), can have a negative impact on brain development. Dexamethasone (DEX) is a synthetic GC used in preterm pregnancies to promote lung maturation. However, prenatal exposure to DEX induces an anxious-like behaviour in male and female offspring at adulthood. Notably, only males respond positively to therapeutics with a proposed anxiolytic.

Objectives Since the influence of prenatal DEX on neurodevelopmental behaviour remains to be elucidated and could help explain this difference in drug efficacy, we aim to clarify the effects of this GC on neurodevelopment during infancy, comparing male and female offspring neurodevelopment at this early age.

Methodology To obtain an animal model of chronic anxiety, Wistar pregnant dams were injected subcutaneously with DEX (1mg/kg) on gestational days 18 and 19. The vestibular system development, locomotion, upper limbs strength, discriminatory ability, auditory response and eye opening day were assessed in male and female offspring between P5 and P17. Animal procedures were approved by the Animal Welfare Committee and done in agreement with the law.

Results Male and female offspring prenatally exposed to DEX had a better performance in the tests assessing the vestibular system development and discriminatory ability, especially at P5 and P6. Additionally, DEX anticipated the day of eye opening and had a positive impact in the upper limb strength of the offspring of both sexes. However, the locomotor ability and auditory response were impaired comparing with controls.

Conclusion Exposure to DEX improves limb strength, balance, spatial orientation and anticipates eye opening. These results may suggest that prenatal DEX exposure promotes offspring development and maturation in both males and females. Prenatal DEX did not differently affect male and female neurodevelopment at early age. It remains to clarify the underlying motives that induce a dimorphic gender response to anxiolytic therapy in adulthood.

P955Non-invasive mapping: what is the minimal number of electrodes needed to obtain a good spatial resolution of the activation map?

Introduction and aims

The 12-lead ECG is highly inaccurate for localization of the site of origin of supraventricular and ventricular arrhythmias.  Non-invasive mapping systems (ECGI) based on a high number of electrodes recording the electrical activity on the surface of the torso have already proven good accuracy for mapping different arrhythmic substrates. The aim of this study was to assess what is the minimal number of leads needed to obtain a precise mapping with the ECGI.

Methods

This study enrolled 14 patients (9 male, median age 50 (44-58) years) referred to our center for catheter ablation of premature ventricular contractions (PVC). Patients underwent pre-procedural ECGI using the epicardial and endocardial mapping system . This system uses the DICOM images from contrast computed tomography of the heart and up to 28 adhesive electrodes with 8 leads each, adding up to 224 body-surface leads. All patients underwent invasive electroanatomical mapping and ablation with the magnetic navigation system. We analysed the number of recording leads used to construct the non-invasive activation map of the PVCs and the accuracy and the spatial resolution of the map when comparing to the invasive map. We then reprocessed the exam, using progressively less leads until we only left the leads placed in the standard 12 lead ECG positions and evaluated the concordance with the invasive map as well as the spatial resolution. We considered an earliest activation site (EAS) area of 1 cm2 a good spatial resolution and using a ROC curve we calculated the minimal number of leads necessary to obtain a good spatial resolution.

Results

The median number of electrodes used for the initial map was 170 (138-177). Concordance between non-invasive and invasive site of origin occurred in 11 out of 14 patients. The results are presented in the Table. The minimal number of electrodes to have a good spatial resolution was 100. The area of EAS was significantly lower when using more than 100 leads, respectively 0.65 (0.5-1) cm2 versus 3 (1.6-5) cm2, p < 0.001.

Conclusions

The minimal number of leads to achieve a good spatial resolution was high.  Reducing the number of leads resulted in a significant decrease in spatial resolution and a lower concordance rate.

ECGI data Number of adhesive electrodes Median number of leads Amycard/Carto concordance Median area of EAS in the ECGI (cm2) Maximal nº electrodes 170 (138-177) 11/14 0.64 (0.5-0.9) 12 electrodes 76 (61-80) 11/14 1.6 (1.4-2.6) 6 electrodes (2 Ant, 2 Lat ,2 Post) 38 (32-44) 9/14 4.3 (3.2-5.4) 12 leads 12 0/14 - Ant anterior; Lat: lateral; Post: posterior; EAS: early activation site.

Abstract Figure. Area of EAS according to the N of leads

Trypanosoma cruzi calreticulin: In vitro modulation of key immunogenic markers of both canine tumors and relevant immune competent cells

Recombinant calreticulin from Trypanosoma cruzi (rTcCalr), the parasite responsible for Chagas' disease, binds to Canine Transmissible Venereal Tumor (CTVT) cells from primary cultures and to a canine mammary carcinoma cell line. A Complement-binding assay indicated that interaction of the first component C1q with these tumor cells operated independently of the rTcCalr-presence. This apparent independence could be explained by the important structural similarities that exist among rTcCarl, endogenous normal canine and/or mutated calreticulins present in several types of cancer. In phagocytosis assays, tumor cells treated with rTcCalr were readily engulfed by macrophages and, co-cultured with DCs, accelerated their maturation. In addition, DCs maturation, induced by tumor cells co-cultured with rTcCalr, activated T cells more efficiently than DCs, treated or not with LPS. In an apparent paradox, a decrease in MHC Class I expression was observed when these tumor cells were co-cultivated with rTcCalr. This decrease may be related to a down regulation signaling promoting the rescue of MHC I. Possibly, these in vitro assays may be valid correlates of in vivo sceneries. Based on these results, we propose that rTcCalr improves in vitro the immunogenicity of two widely different tumor cell lines, thus suggesting that the interesting properties of rTcCalr to boost immune responses warrant future studies.