Inputs, amplification and sinks of perfluoroalkyl substances at coastal Antarctica

The sources, biogeochemical controls and sinks of perfluoroalkyl substances, such as perfluoroalkyl acids (PFAAs), in polar coastal regions are largely unknown. These were evaluated by measuring a large multi-compartment dataset of PFAAs concentrations at coastal Livingston and Deception Islands (maritime Antarctica) during three austral summers. PFAAs were abundant in atmospheric-derived samples (aerosols, rain, snow), consistent with the importance of atmospheric deposition as an input of PFAAs to Antarctica. Such PFAAs deposition was unequivocally demonstrated by the occurrence of PFAAs in small Antarctic lakes. Several lines of evidence supported the relevant amplification of PFAAs concentrations in surface waters driven by snow scavenging of sea-spray aerosol-bound PFAAs followed by snow-melting. For example, vertical profiles showed higher PFAAs concentrations at lower-salinity surface seawaters, and PFAAs concentrations in snow were significantly higher than in seawater. The higher levels of PFAAs at Deception Island than at Livingston Island are consistent with the semi-enclosed nature of the bay. Concentrations of PFOS decreased from 2014 to 2018, consistent with observations in other oceans. The sink of PFAAs due to the biological pump, transfer to the food web, and losses due to sea-spray aerosols alone are unlikely to have driven the decrease in PFOS concentrations. An exploratory assessment of the potential sinks of PFAAs suggests that microbial degradation of perfluoroalkyl sulfonates should be a research priority for the evaluation of PFAAs persistence in the coming decade.

Metatranscriptomic responses and microbial degradation of background polycyclic aromatic hydrocarbons in the coastal Mediterranean and Antarctica

Although microbial degradation is a key sink of polycyclic aromatic hydrocarbons (PAH) in surface seawaters, there is a dearth of field-based evidences of regional divergences in biodegradation and the effects of PAHs on site-specific microbial communities. We compared the magnitude of PAH degradation and its impacts in short-term incubations of coastal Mediterranean and the Maritime Antarctica microbiomes with environmentally relevant concentrations of PAHs. Mediterranean bacteria readily degraded the less hydrophobic PAHs, with rates averaging 4.72 ± 0.5 ng L h-1. Metatranscriptomic responses showed significant enrichments of genes associated to horizontal gene transfer, stress response, and PAH degradation, mainly harbored by Alphaproteobacteria. Community composition changed and increased relative abundances of Bacteroidota and Flavobacteriales. In Antarctic waters, there was no degradation of PAH, and minimal metatranscriptome responses were observed. These results provide evidence for factors such as geographic region, community composition, and pre-exposure history to predict PAH biodegradation in seawater.

Snow-Dependent Biogeochemical Cycling of Polycyclic Aromatic Hydrocarbons at Coastal Antarctica

The temporal trend of polycyclic aromatic hydrocarbons (PAHs) in coastal waters with highly dynamic sources and sinks is largely unknown, especially for polar regions. Here, we show the concurrent measurements of 73 individual PAHs and environmental data, including the composition of the bacterial community, during three austral summers at coastal Livingston (2015 and 2018) and Deception (2017) islands (Antarctica). The Livingston 2015 campaign was characterized by a larger snow melting input of PAHs and nutrients. The assessment of PAH diagnostic ratios, such as parent to alkyl-PAHs or LMW to HMW PAHs, showed that there was a larger biodegradation during the Livingston 2015 campaign than in the Deception 2017 and Livingston 2018 campaigns. The biogeochemical cycling, including microbial degradation, was thus yearly dependent on snow-derived inputs of matter, including PAHs, consistent with the microbial community significantly different between the different campaigns. The bivariate correlations between bacterial taxa and PAH concentrations showed that a decrease in PAH concentrations was concurrent with the higher abundance of some bacterial taxa, specifically the order Pseudomonadales in the class Gammaproteobacteria, known facultative hydrocarbonoclastic bacteria previously reported in degradation studies of oil spills. The work shows the potential for elucidation of biogeochemical processes by intensive field-derived time series, even in the harsh and highly variable Antarctic environment.

Differences in the respiratory swings in COPD and ILD candidates for lung transplantation: a critical concern interpreting central pulmonary pressures

Background

In different clinical scenarios (i.e., obesity, COPD, exercise, mechanical ventilation), the swings in intrathoracic pressure are much larger, and end-expiratory (Pee) pressure can be significantly greater than atmospheric pressure. In these scenarios, the intravascular (Piv) pulmonary pressure can overestimate the true transmural (tm) value and it is recommended to read the average of Piv over a few respiratory cycles (Pmrc) [1–3].

Purpose

To analyze the respiratory swings and the effect of esophageal pressure (PES) (as a surrogate of intrathoracic pressure) on the reading of Piv tracings during the RHC at rest in COPD and interstitial lung disease (ILD) candidates for lung transplantation (LTx).

Methods

Thirty-one COPD (15) and ILD (16) candidates for LTx underwent RHC. End-expiratory and mean respiratory cycle measurements were obtained. The respiratory swing was estimated as the difference between maximum-minimum values of Piv. Ten patients (5 COPD/5 ILD) underwent simultaneous RHC and PES (Micro-balloon Esophageal Catheter, LATITUDE) to assess the Ptm (Piv − PES) [4].

Results

Both demographic (11F/20M, 60±7 yrs, 25±4 kg/m2) and hemodynamic data (mPAP 24±9 mmHg, pulmonary arterial occlusion pressure [PAOP] 8.6±4 mmHg, right atrial pressure [RAP] 5.2±3.9 mmHg, pulmonary vascular resistance 3.5±2.6 Wu) did not show significant differences between ILD and COPD except the cardiac index (ILD: 2.8±0.8 vs. COPD: 2.4±0.3 L/min/m2). Intravascular RAPee and PAOPee were higher than mrc values in both groups (Fig 1). However, transmural RAPee and PAOPee were similar to and correlated with (r=0.62 and 0.69, respectively; p<0.05) transmural Pmrc values. PESee values were positive in COPD and ILD (3.0±2.2 vs. 3.3±2.0 mmHg, NS). All ILD had negative PESmrc values and were lower than COPD patients (−1.76±1.7 vs. 0.78±1.6 mmHg, p<0.05). ILD PES swings were higher than COPD (10.9±3.7 vs. 8.3±1.4 mmHg), although it did not reach statistical significance (p=0.08). The lower forced vital capacity (%), the more negative the PESmrc (Fig 2A). ILD pts showed higher transmural to intravascular Pmrc (p<0.05) (Fig 2B).

Conclusion

End-expiratory intravascular RAP and PAOP overestimates the mean respiratory cycle pressures in COPD and ILD candidates for LTx. Averaging pulmonary vascular pressure tracings over the respiratory cycle would be accurate in COPD but could underestimate transmural values in ILD candidates for LTx. The reading of mean respiratory cycle pressure could not be enough to correct the pulmonary pressures measurement error associated with the presence of large swings of intrathoracic pressure.

Funding Acknowledgement

Type of funding sources: None.

Aortic flow patterns by 4D flow CMR in Marfan and Loeys-Dietz patients before and after valve sparing aortic root replacement: a comparison with healthy volunteers

Introduction

Abnormal aortic flow patterns in patients with a connective tissue disorder (CTD), such as Marfan or Loeys-Dietz syndrome, may contribute to aortic root dilation [1,2]. Valve sparing aortic root replacement, which is effective in reducing the risk of aortic dissection in case of severe dilation, may also normalize flow patterns beyond the replaced aorta and potentially slow its progressive aortic dilation.

Purpose

To assess aortic flow dynamics in patients with a CTD by 4D flow cardiovascular magnetic resonance (CMR) before and after valve sparing aortic root replacement, and to compare the results with those of healthy volunteers (HV).

Methods

Patients with Marfan or Loeys-Dietz syndrome underwent two non-contrast enhanced 4D flow CMR, one before and another after undergoing valve sparing aortic root replacement. Healthy volunteers matched for age, sex and BSA were also included for comparison. Maximum velocity, in-plane rotational flow (IRF), systolic flow reversal ratio (SFRR) and wall shear stress (WSS) magnitude and its axial and circumferential components were obtained at 24 planes covering the thoracic aorta from the sinotubular junction to the descending aorta at the diaphragmatic level [3–5].

Results

Sixteen patients and 21 healthy volunteers were included. Demographic and clinical data is presented in Table. The mean time between the CMR prior and posterior to surgery was 15 months. Compared to HV, patients with CTD before intervention presented lower maximum velocity at the proximal ascending aorta (Fig. 1A), lower IRF and circumferential WSS at the arch and the proximal descending aorta (Fig. 1B and F), lower magnitude and axial WSS at the proximal ascending and descending aorta (Fig. 1E and D), and increased SFRR at the proximal descending aorta (Fig. 1C). The intervention completely restored maximum velocity and partially-restored physiological helical flow and circumferential WSS, but barely improved axial WSS and SFRR.

Conclusion

Valve sparing aortic root replacement in patients with Marfan or Loeys-Dietz syndrome partially restore to physiological level both in-plane rotational flow and circumferential wall shear stress in the descending aorta. This flow normalization may contribute to prevent progressive dilation after the surgery.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III (Spain) (PI17/00381)Spanish Society of Cardiology (SEC/FEC-INV-CLI 20/015)

Mapping of thoracic aorta growth rate on serial self-navigated 3D whole-heart magnetic resonance angiographies by image registration

Introduction

Accurate and reproducible assessment of aortic diameters and their growth rate is of key importance for the management of patients with thoracic aortic aneurysms [1,2]. It has been recently shown that image registration permits the assessment of progressive aortic dilation on ECG-gated contrast-enhanced CT angiography, outperforming manual quantification and allowing for 3D aortic size and growth mapping [3]. However, exposure to radiation makes it convenient to limit the use of CT for serial follow-up, especially in young patients. Self-navigated 3D whole-heart CMR acquisitions provides excellent image quality overcoming these limitations [4].

Purpose

To evaluate the accuracy and reproducibility of registration-based assessment of aortic dilation using self-navigated 3D whole-heart CMR acquisitions.

Methods

Fifteen patients with two self-navigated 3D whole-heart CMR images obtained at least 1 year apart were included. Aortic root and thoracic aorta diameters were measured by 2 independent observers both manually (multiplanar reconstruction) and with the registration-based technique. To perform registration-based assessment, the aorta was semi-automatically segmented and typical anatomical landmarks were placed by each observer at baseline [3]. Geometrical mapping between baseline and follow-up acquisitions was obtained using deformable image registration, and applied to the baseline aortic surface points to obtain their location at follow-up. Finally, aortic diameters and their growth rate were automatically measured and used to calculated 3D aortic dilation maps. Agreement between techniques and their inter-observer reproducibility were calculated.

Results

Patients age was 27.2±14.5 years and 40% were male. Mean follow-up duration was 2.7±1.6 years. Compared to manual assessment, the registration-based technique presented low bias and excellent agreement for aortic diameters (Table 1), and low bias and moderate agreement for growth rates both in the aortic root and the thoracic aorta (Table, Fig. 1A). The techniques presented similar inter-observer reproducibility in the assessment of aortic diameters (Table 1), while the registration-based method demonstrated much higher inter-observer reproducibility in the assessment of growth rates in the aortic root and the thoracic aorta (Table 1, Fig. 1A and B). Three-dimensional mapping of thoracic aortic diameters and growth was highly reproducible (mean regional ICC=0.90 for diameters; 0.82 for growth rate).

Conclusion

The assessment of the dilation rate of the thoracic aorta via registration of serial self-navigated 3D whole-heart CMR acquisitions is accurate and reproducible in the aortic root and the thoracic aorta. Thus, it allows to assess local aortic growth without the drawbacks of CT.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Instituto de Salud Carlos III and Ministerio de Ciencia e Innovaciόn (Spain)

Polycyclic Aromatic Hydrocarbon Degradation in the Sea-Surface Microlayer at Coastal Antarctica

As much as 400 Tg of carbon from airborne semivolatile aromatic hydrocarbons is deposited to the oceans every year, the largest identified source of anthropogenic organic carbon to the ocean. Microbial degradation is a key sink of these pollutants in surface waters, but has received little attention in polar environments. We have challenged Antarctic microbial communities from the sea-surface microlayer (SML) and the subsurface layer (SSL) with polycyclic aromatic hydrocarbons (PAHs) at environmentally relevant concentrations. PAH degradation rates and the microbial responses at both taxonomical and functional levels were assessed. Evidence for faster removal rates was observed in the SML, with rates 2.6-fold higher than in the SSL. In the SML, the highest removal rates were observed for the more hydrophobic and particle-bound PAHs. After 24 h of PAHs exposure, particle-associated bacteria in the SML showed the highest number of significant changes in their composition. These included significant enrichments of several hydrocarbonoclastic bacteria, especially the fast-growing genera Pseudoalteromonas, which increased their relative abundances by eightfold. Simultaneous metatranscriptomic analysis showed that the free-living fraction of SML was the most active fraction, especially for members of the order Alteromonadales, which includes Pseudoalteromonas. Their key role in PAHs biodegradation in polar environments should be elucidated in further studies. This study highlights the relevant role of bacterial populations inhabiting the sea-surface microlayer, especially the particle-associated habitat, as relevant bioreactors for the removal of aromatic hydrocarbons in the oceans.

Occurrence and air-water diffusive exchange legacy persistent organic pollutants in an oligotrophic north Patagonian lake

In this study, the occurrence and diffusive air-water exchange of POPs in Panguipulli Lake (39°42'S-72°13'W), an oligotrophic lake located in northern Patagonia (Chile), were determined. Air and water samples were collected between March and August 2017 (autumn-winter) and analyzed for concentrations of OCPs (α-HCH, β-HCH, γ-HCH and HCB) and PCBs (PCB-28,-52,-101,-118,-153,-158,-180) using gas chromatography coupled with an electron capture detector. The direction of air-water exchange direction was evaluated using a fugacity approach (ƒ_w ƒ_a^-1), and net diffusive exchange fluxes (F_AW, ng m^-2 d^-1) were also estimated. Total ∑₄OCP levels in air ranged from 0.31 to 37 pg m^-3, with a maximum for β-HCH, while Σ₇PCB levels ranged from 3.05 to 43 pg m^-3. The most abundant congener was PCB-153, accounting for 60% of the total PCBs in air. Surface water ∑₄OCPs measured in this study ranged from 1.01 to 3.9 pg L^-1, with γ-HCH predominating, while surface water Σ₇PCB levels ranged from 0.32 to 24 pg L^-1, with PCB-101, PCB-118, and PCB-153 presenting the highest levels. Diffusive air-water exchanges of HCB, α-HCH, γ-HCH and PCBs in the form of volatilization from the lake to air predominated; in contrast, for β-HCH net deposition dominated during the sampling period. Estimates suggested faster microbial degradation in the dissolved phase compared to atmospheric degradation for all analyzed POPs. Overall, these results could indicate that the oligotrophic lakes of northern Patagonia act as a secondary source of atmospheric POPs, mainly PCBs and some OCPs. This study is a first attempt to understand the occurrence of POPs in air and water, as well as their dynamics in oligotrophic lakes in the southern hemisphere.

Outcomes of patients with left ventricular noncompaction and preserved ejection fraction

Funding Acknowledgements

Type of funding sources: None.

INTRODUCTION 

Left ventricular noncompaction (LVNC) is a poorly defined entity with heterogeneous prognosis. LV ejection fraction (LVEF) is one of the main predictors of major adverse cardiovascular events (MACE). However, outcomes of LVNC patients with preserved LVEF (pEF) remain uncertain.

PURPOSE 

The aim of our study was to determine the incidence and predictors of MACE in LVNC patients with pEF as well as to assess the evolution of LVEF throughout follow-up. 

METHODS 

We conducted a retrospective, longitudinal, multicentre cohort study. Consecutive patients with transthoracic echocardiography (TTE) and/or cardiac magnetic resonance (CMR) diagnostic criteria for LVNC and initially pEF (LVEF≥50%) were recruited. MACE were defined as a composite of heart failure (HF), ventricular arrhythmias (VA), systemic embolisms (SE) and/or all-cause mortality. Progressive systolic dysfunction was defined as an LVEF < 50% at last TTE and/or an absolute ≥10-point decrease in LVEF from first to last TTE. Lower limit of LVEF CMR values were considered 50-57% according to current recommendations. Cox-regression analysis was used for MACE and logistic regression was used for progressive systolic dysfunction (only first and last TTE were available).

RESULTS 

A total of 305 patients from 12 centres were included from 2000 to 2018. Age was 38 ± 19 years and 165 (54%) were men. LVEF was 62 ± 8% and 8% had late gadolinium enhancement (LGE). During a median follow-up of 4.7 (IQR 2.1-7.4) years, MACE occurred in 40 (13%) patients with an incidence rate of 2.73 (95% CI 2.00-3.72) events per 100 person-years: 8 HF, 27 VA, 3 SE and 5 deaths. LVEF by CMR (HR 0.95, 95% CI 0.91-0.99, p = 0.0048) and hypertension (HR 2.30, 95% CI 1.08-4.89, p = 0.031) were the only variables independently associated with the endpoint. Patients with lower limit LVEF values showed an increased risk of MACE (Figure 1). LGE was not associated.

Sixty-one (21%) patients experienced progressive systolic dysfunction: 31 (11%) had an LVEF < 50% and 48 (17%) an absolute ≥10-point decrease in LVEF at last follow-up. On multivariate analysis, LVEF by CMR was the only independent predictor (OR 0.93, 95% CI 0.89-0.98, p = 0.008). Patients with lower limit LVEF values had an increased risk (Figure 2). In this subgroup, LGE was also associated with the endpoint (HR 10.69, 95% CI 1.97-58.13, p = 0.006).

CONCLUSIONS 

Patients with left ventricular noncompaction and preserved ejection fraction carry a moderate risk of major adverse cardiovascular events and progressive systolic dysfunction. LVEF remains the main predictor of outcomes in this subgroup. Patients with lower limit LVEF values are at increased risk, probably suggesting subclinical systolic dysfunction. Therefore, they should be carefully monitored. Abstract Figure. Kaplan Meier cuves for MACE  Abstract Figure. Risk of progressive systolic dysfunction

Clinical, laboratory, electrocardiogaphic and multimodality imaging outcome predictors in cardiac amyloidosis

Background

Cardiac affectation in amyloidosis is presented among 50% patients what implies worse prognostic. Early diagnosis and prognostic stratification is mandatory after the appearance of new therapies that could modify the course of the disease.

Purpose

The aim of the present study was to evaluate the main outcome predictors with multiparametric approach including clinical, laboratory, electrocardiographic and imaging parameters in patients with cardiac amyloidosis (CA).

Methods

We recruited patients (p) prospectively followed in our cardiomyopathy unit, for a mean period of 10 years (from 2010 to 2020) who were diagnosed with CA. Baseline clinical, laboratory and echocardiographic data were obtained. We collected cardiovascular risk factors and previous events. We performed a multimodality imaging study including echocardiogram (TTE) and cardiac magnetic resonance (CMR). TTE hallmarks of CA were recorded, as well as CMR parameters of cardiac function, myocardial mass and tissue characterization. Finally we evaluated the parameters related with mortality in the follow-up.

Results

A total of 98 p were included, with a mean age of 67.5±16.9 years old. Mean follow-up was 42,2±32 months. 22 p (24,4%) had light-chain amyloidosis (AL), 34 p (37,8%) wild type transthyretin amyloidosis (ATTRwt) and 34 p (37,8%) familiar transthyretin amyloidosis (ATTRm). 43p (47.78%) died in the follow-up. Factors related with mortality in the the follow-up where the age (HR 1.08, ppresence of hypertension (HR 2.81, p=0,002) diabetes (HR 3.12, p=0,001) and previous stroke (HR 2.69, p=0,01); NYHA class at diagnosis (HR 2.49, p<0.001), low voltage (HR 2.31, p=0,008) and pseudoinfarct pattern at ECG (HR 1.9, p=0,003); elevated BNP (HR 10.29, p<0.001) and creatinine (HR 1.42, p=0,02); septum (HR 1.09, p=0,001) and posterior wall (HR 1,14, p<0,001)thickness, left ventricular ejection fraction (HR 0.96, p=0,0031) global longitudinal strain (HR 1.18, p<0.001), ratio E/A (HR 2.29, p<0,001) and E/e' (HR 1.13, p=0,003) and left atrium size (HR 1,05, p=0,006) at echo; and the presence of left atrium fibrosis (HR 4.17, p>0,001) and extension of late gadolinium enhancement (HR 1,06, p=0,03) at CMR. When evaluated within a multivariate analysis in a Cox regression model, the independent variables associated with mortality were NYHA class at diagnosis (p=0.002) and amyloidosis type (p=0.002) ATTRm had a better prognosis than ATTRwt and AL (Log-rank p<0.001).

Conclusion

Mortality in cardiac amyloid patients is high. Clinical parameters like hypertension, diabetes, previous stroke and NYHA class at diagnosis; laboratory parameters like BNP and creatinine, main systolic and diastolic function at TTE, presence of auricular fibrosis and extension of late gadolinium enhancement at CRM are related with mortality in the follow-up. Among different types of CA, patients with ATTRm had a better prognosis, which may have therapeutic implications with the appearance of new therapies.

Funding Acknowledgement

Type of funding sources: None. Mortality

Clinical impact on treatment and prognosis of advanced cardiac imaging with echocardiography in the acute setting of a COVID-19 infection

Background and objectives

Despite myocardial injury being related to excess mortality in acute COVID-19 infection, its impact on imaging findings remains unclear. This study aimed to characterize transthoracic echocardiographic (TTE) findings in patients admitted with COVID-19 infections and its impact on management and prognosis.

Methods

A prospective observational cohort study was performed among 66 COVID-19 patients who were admitted to a tertiary center between March 1 and May 25, 2020 and underwent TTE. High-sensitivity troponin I (hs-cTnI) data, echocardiographic assessment of right and left ventricular (LV) functional parameters, strain, and myocardial work analysis were obtained.

Results

2025 patients were admitted with COVID-19 and in 200 a complete TTE study was performed. Due to poor image quality, only 66 studies were included in the final analysis. The median age was 62 years (IQR, 55–70) and 59.1% of patients were males. The most common comorbidity was hypertension (47%), followed by smoking history (30.3%), atrial fibrillation (9.1%), and chronic obstructive pulmonary disease (7.9%). More than half of the patients (39, 59%) were admitted to the ICU, and half of them (33, 50%) required invasive mechanical ventilation. TTE was mainly indicated because of concerns for systemic conditions (50%) and evaluation of hemodynamic assessment (30%). Thirty-six patients (54.5%) had an abnormal TTE result and 57% had elevated hs-cTnI levels. The most common cardiac abnormality was LV diastolic dysfunction in 33% of the patients, followed by right ventricular dysfunction (12%) and LV dysfunction (6%) (Figure 1). LV GLS was reduced in 48.5% of the cases. Myocardial work performance indices were all reduced in patients with an abnormal TTE (GWI 30%, GCW 30%, GWW 40%, and GWE 40%), although differences were not significant (P>0.2 for all parameters). Patients with an abnormal TTE were older and presented a higher cardiovascular risk profile. There were no significant differences in the levels of D-dimer, NTproBNP, and hs-cTnI between patients with and without diastolic dysfunction, RV, or LV dysfunction (P>0.3 for all parameters). Using Spearman rank correlation, there was an inverse relationship between hs-cTnI and LV strain and myocardial work analysis. TTE results impacted clinical management in 60 patients, mainly de-escalation of medical treatment (Figure 2). Abnormal TTE results did not impact in-hospital outcomes.

Conclusions

Severe echocardiographic abnormalities are uncommon in hospitalized patients with COVID-19 infections, presenting mostly with subclinical myocardial changes, such as diastolic dysfunction, reduced LV GLS, and myocardial work indices, both associated with high-sensitivity troponin I elevation. An echocardiographic study should be limited to rule out long-term ICU complications or to evaluate hemodynamic instability. Although TTE was a valuable tool for guiding management, it had no significant impact on prognosis.

Funding Acknowledgement

Type of funding sources: None. Figure 1. Findings on TTE studies.Figure 2. Changes in management.

Prognosis of left ventricular noncompaction with preserved ejection fraction

Introduction

Left ventricular noncompaction (LVNC) is a poorly defined entity with heterogeneous prognosis. LV ejection fraction (LVEF) is one of the main predictors of major adverse cardiovascular events (MACE). However, outcomes of LVNC patients with preserved LVEF (pEF) remain uncertain.

Purpose

The aim of our study was to determine the incidence and predictors of MACE in LVNC patients with pEF as well as to assess the evolution of LVEF throughout follow-up.

Methods

We conducted a retrospective, longitudinal, multicentre cohort study. Consecutive patients with transthoracic echocardiography (TTE) and/or cardiac magnetic resonance (CMR) diagnostic criteria for LVNC and initially pEF (LVEF≥50%) were recruited. MACE were defined as a composite of heart failure (HF), ventricular arrhythmias (VA), systemic embolisms (SE) and/or all-cause mortality. Progressive systolic dysfunction was defined as an LVEF<50% at last TTE and/or an absolute ≥10-point decrease in LVEF from first to last TTE. Lower limit of LVEF values were considered 50–53% for TTE and 50–57% for CMR, according to current recommendations.

Results

A total of 305 patients from 12 centres were included from 2000 to 2018. Age was 38±19 years, 165 (54%) were men and 185 (61%) were probands. LVEF was 62±8% and 8% had late gadolinium enhancement (LGE). During a median follow-up of 4.7 (IQR 2.1–7.4) years, MACE occurred in 40 (13%) patients with an incidence rate of 2.96 (95% CI 2.17–4.04) events per 100 person-years: 8 HF, 27 VA, 3 SE and 5 deaths. LVEF by TTE (HR 0.95, 95% CI 0.90–0.99, p=0.035) and age (HR 1.02, 95% CI 1.01–1-04, p=0.04) were the only variables independently associated with the endpoint. Patients with lower limit LVEF values showed an increased risk of MACE (Figure 1). Among probands, those with family aggregation presented a higher incidence of MACE compared to nonfamilial cases (HR 2.74, p=0.043). A positive genotype was not associated.

Sixty-one (21%) patients experienced progressive systolic dysfunction: 31 (11%) had an LVEF<50% and 48 (17%) an absolute ≥10-point decrease in LVEF at last follow-up. On multivariate analysis, LVEF by CMR was the only independent predictor (HR 0.96, 95% CI 0.92–0.99, p=0.031). Patients with lower limit LVEF values had an increased risk (Figure 2). In this subgroup, LGE was also associated with the endpoint (HR 3.52, p=0.011). Family aggregation was not associated, while a positive genotype correlated with lower risk (HR 0.52, p=0.029).

Conclusions

Patients with left ventricular noncompaction and preserved ejection fraction carry a moderate risk of major adverse cardiovascular events and progressive systolic dysfunction. LVEF remains the main predictor of outcomes in this subgroup. Patients with lower limit LVEF values are at increased risk, probably suggesting subclinical systolic dysfunction. Therefore, they should be carefully monitored.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Routine advanced echocardiography in the evaluation of cardiovascular sequelae of COVID19 survivors with elevated cardiovascular biomarkers

Background

COVID19 has been related to elevated CVB and biventricular dysfunction during hospitalization. However, it is unknown whether patients with biomarker elevation exhibit long-lasting abnormalities in cardiac function.

Purpose

To determine, using advanced echocardiography, the prevalence and type of cardiovascular sequelae after COVID19 infection with marked elevation of cardiovascular biomarkers (CVB), and their prognostic implications.

Methods

All patients admitted from March 1st to May 25th, 2020 to a tertiary referral hospital were included. Patients with cardiovascular disease antecedent, death during admission, or the first 30 days after discharge were excluded. Patients with hs-TnI >45 ng/L, NT-proBNP >300 pg/ml, and D-dimer >8000 ng/ml were separated based on each CVB elevation and matched with COVID controls (three biomarkers within the normal range) based on intensive care requirements and age.

Results

From a total of 2025 hospitalized COVID19 patients, 80 patients with significantly elevated CVB and 29 controls were finally included. No differences in baseline characteristics were observed among groups, but elevated CVB patients were sicker. Follow-up echocardiograms showed no differences among groups regarding LVEF or RV diameters, but TAPSE was lower if hs-TnI or D-dimer were elevated. Hs-TnI patients also had lower global myocardial work and global longitudinal strain. The presence of an abnormal echocardiogram was more frequent in the elevated CVB group compared to controls (23.8 vs 10.3%, P=0.123) but mainly associated with mild abnormalities in deformation parameters. Management did not change in any case and no major cardiovascular events except deep vein thrombosis occurred after a median follow-up of 7 months (Figure 1).

Conclusions

Minimal abnormalities in cardiac structure and function are observed in COVID19 survivors without previous cardiovascular diseases who presented a significant CVB rise at admission, with no impact on patient management or short-term prognosis. These results do not support a routine screening program after discharge in this population.

Funding Acknowledgement

Type of funding sources: None.

Evaluation of myocardial strain assessed by CMR tissue-tracking to predict adverse cardiovascular events in patients with cardiac amyloidosis

Background

Cardiac affectation in amyloidosis is presented among 50% patients what implies worse prognostic. Early diagnosis and prognostic stratification is mandatory after the appearance of new therapies that could modify the course of the disease.

Purpose

The aim of our study was to assess the prognostic value of cardiac magnetic resonance parameters, including Tissue deformation, in cardiac amyloidosis patients.

Methods

We recruited patients (p) prospectively followed in our cardiomyopathy unit, for a mean period of 10 years (from 2010 to 2020) who were diagnosed with CA. Baseline clinical, laboratory and echocardiographic data were obtained. Contrast-enhanced CMR was performed on a 1.5 T clinical scanner. Routine analysis was performed with a semi-automatic software for volumetric analysis. When late gadolinium enhancement was present, percentage of area of enhancement (LGE) was calculated.All strain parameters were measured off-line using dedicated software. Left ventricular circumferential strain (CS) measurements were obtained using mid-ventricular level short-axis cine views. Longitudinal strain (LS) derived from cine SSFP of 2-, 3-, and 4-chamber long axis views.Finally we evaluated the CMR parameters related with the combined event of mortality and heart failure in the follow-up.

Results

A total of 98 p were included, with a mean age of 67.5±16.9 years old. Mean follow-up was 42,2±32 months. 22 p (24,4%) had light-chain amyloidosis (AL), 34 p (37,8%) wild type transthyretin amyloidosis (ATTRwt) and 34 p (37,8%) familiar transthyretin amyloidosis (ATTRm). 59p (60,8%) died or present heart failure during the follow-up. Patients who died or present heart failure in the follow-uo had lower left ventricular ejection fraction (48,25±12,2% vs 56,13±11,03%, p=0,003), higher myocardial mass (156,05±54,8g vs 120,84±56,1g, p=0,007), higher LGE (8,6±6,8% vs 4,4±2%), worst GLS (−14,76±6,1% vs −18,67±6,2%) and worst GCS (−23,3±9,7% vs −30,04±9,1%). Both, GLS and GCS were independently associated with the combined event of dead or heart failure when evaluated within a multivariate analysis in a Cox regression model, but GCS was the stronger predictor of events in the follow-up over other CMR parameters like LGE an myocardial mass (p<0,001). Tertile distribution for GCS identified subgroups with different adverse events, particularly for the lowest-risk tertile: GCS <−34%, who had a combinated event in 13,6% of cases, significantly lower than patients in the mid-risk tertile (41,5%) and highest-risk tertile (53,8%) (Log-rank p=0,02)

Conclusion

Mortality and appearance of heart failure in cardiac amyloid patients is high. The assessment of myocardial strain parameters by CMR tissue-tracking in this population is useful to predict adverse outcomes in the follow-up. Particularly, GCS, stratify patients in subgroups with different risk of events, with added value to classical CMR parameters.

Funding Acknowledgement

Type of funding sources: None. Death & Heart Failure by GCS

Do morphological, haemodynamic and biomechanical parameters relate to aortic growth rate in chronic type B aortic dissection? A 4D flow CMR study

Background

Aortic dissection (AD) is the most devastating complication of thoracic aortic disease (1). In the chronic phase, yearly clinical and imaging follow-up of the maximum aortic diameter is recommended, since indication for thoracic endovascular aortic repair or surgery is suggested by guidelines in case of thoracic aortic enlargement or false lumen (FL) aneurysms (2). Most of the reported parameters related adverse events in chronic AD are focused on morphological variables (3) and not on the haemodynamics and biomechanics of the FL.

Purpose

To evaluate the relationship between aortic growth rate and anatomical variables, flow patterns and aortic stiffness in patients with chronic type B AD.

Methods

Forty-one patients with chronic type B aortic dissection, no connective tissue disorders and with an imaging follow-up including two computed tomography angiograms (CTA) acquired at least 3 years apart underwent contrast-enhanced 4D-flow CMR and MR angiography (MRA). The FL volume was segmented from MRA, and velocity data inside the 3D volume of the FL was extracted from 4D-flow CMR and used for parameter quantification. Retrograde systolic and diastolic flow, wall shear stress (WSS) and in-plane rotational flow (IRF) were calculated at 8 equidistant planes in the distal descending aorta (DAo), from the pulmonary bifurcation to the diaphragmatic level, and averaged values were used [4]. Aortic stiffness in the FL was assessed in terms of pulse wave velocity (PWV), which was calculated from the third supraortic trunk to the diaphragmatic level on 4D-flow CMR [5]. The percentage of thrombus in the FL was calculated as the ratio of thrombus and FL volumes on MRA. Dominant entry tear area was quantified on the baseline CTA (Figure 1). Aortic growth rate (GR) was defined as the difference between final and baseline aortic diameters as measured on CTA divided by follow-up duration.

Results

Anatomical, haemodynamic and biomechanical parameters are shown in Table. Twenty-five patients have repaired type A AD with residual entry tear and 16 have type B AD. Mean follow-up duration was of 4.9±2.7 years. In bivariate analysis, WSS, IRF and PWV were positively related to GR, whereas dominant entry tear area and percentage of thrombus in the FL showed a positive tendency with GR (Table) (Figure). In multivariate analysis IRF, PWV, dominant entry tear area and thrombus in the FL were positively and independently associated with GR (Table). Retrograde systolic and diastolic flow were not related to GR while WSS tended to statistical significance.

Conclusions

In-plane rotational flow, regional aortic stiffness, dominant entry tear area and percentage of thrombus in the false lumen are positively and independently related to aortic growth rate in patients with chronic type B aortic dissection. Further prospective studies are needed to confirm if the assessment of these parameters may help to identify patients at higher risk of adverse clinical events.

Funding Acknowledgement

Type of funding sources: None. Table 1Figure 1

Accurate and reproducible aortic growth rate mapping via registration of serial contrast-enhanced computed tomography angiograms

Introduction

Accurate assessment of aortic diameters and growth rates is key for clinical management of patients with aortic aneurysms [1]. Manual assessment on multiplanar reformatted views of computed tomography angiograms (CTA) is recommended [1], although its reproducibility in the assessment of growth rates has not been reported [2]. Image registration has been proposed to provide 3D maps of aortic diameters and growth [3], but its accuracy and reproducibility have not been established.

Purpose

To quantify accuracy and inter-observer reproducibility of aortic root and thoracic aorta diameters and growth rate by registration of serial CTAs compared to current standard.

Methods

Forty non-operated patients with ≥2 contrast-enhanced ECG-gated CTA acquired at least 6 months apart were included. Aortic diameters and growth rates were measured in the aortic root and thoracic aorta by two independent observers, both with the current standard and with the registration-based technique. To perform registration-based assessment, each observer semi-automatically segmented the aorta at baseline and located typical anatomical landmarks (Fig. 1A). Then, deformable image registration was used to map baseline and follow-up CT scans and deformation was applied to the baseline aortic surface points to obtain their location at follow-up (Fig. 1B). Finally, aortic root diameters and growth rate and 3D maps of thoracic aortic diameters and growth rate were automatically obtained (Fig. 1C). Agreement between techniques and their inter-observer reproducibility were calculated.

Results

Follow-up duration was 3.3±1.5 years (range 0.52–6.2). Compared with manual assessment, registration-based aortic diameters presented low bias and excellent agreement in the aortic root (0.42 mm, ICC=0.99) and the thoracic aorta (0.55 mm, ICC=0.99), and similar inter-observer reproducibility (ICC=0.99 for both). Compared with manual assessment, registration-based growth rates presented low bias and good agreement in the aortic root (0.12 mm/y, ICC=0.84) and the thoracic aorta (0.03 mm/y, ICC=0.77) (Fig. 2A), and much higher inter-observer reproducibility (ICC=0.96 vs 0.68 in the aortic root, ICC=0.96 vs 0.80 in the thoracic aorta) (Fig. 2B and C). Registration-based aortic growth rates reproducibility at 6 months follow-up was comparable to that obtained by manual assessment at 2.7 years (LoA = [−0.01, 0.33] and LoA = [−0.13, 0.21], respectively). Aortic diameters and growth rate 3D maps were highly reproducible (ICC>0.9) in the whole thoracic aorta.

Conclusions

Progressive aortic dilation assessment via registration of CTAs is accurate and more reproducible than the current standard even over follow-ups as short as 6 months, and further provides robust 3D mapping of aortic diameters and growth rates. Its application may provide new insights in aneurysms pathophysiology and improve the clinical management of these patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study has received funding from the Instituto de Salud Carlos III (PI17/00381). Guala A. has received funding from Spanish Ministry of Science, Innovation and Universities (IJC2018-037349-I). Figure 1. Methodology.Figure 2. Growth rate comparison.

Rain Amplification of Persistent Organic Pollutants

Scavenging of gas- and aerosol-phase organic pollutants by rain is an efficient wet deposition mechanism of organic pollutants. However, whereas snow has been identified as a key amplification mechanism of fugacities in cold environments, rain has received less attention in terms of amplification of organic pollutants. In this work, we provide new measurements of concentrations of perfluoroalkyl substances (PFAS), organophosphate esters (OPEs), and polycyclic aromatic hydrocarbons (PAHs) in rain from Antarctica, showing high scavenging ratios. Furthermore, a meta-analysis of previously published concentrations in air and rain was performed, with 46 works covering different climatic regions and a wide range of chemical classes, including PFAS, OPEs, PAHs, polychlorinated biphenyls and organochlorine compounds, polybromodiphenyl ethers, and dioxins. The rain-aerosol (KRP) and rain-gas (KRG) partition constants averaged 105.5 and 104.1, respectively, but showed large variability. The high field-derived values of KRG are consistent with adsorption onto the raindrops as a scavenging mechanism, in addition to gas-water absorption. The amplification of fugacities by rain deposition was up to 3 orders of magnitude for all chemical classes and was comparable to that due to snow. The amplification of concentrations and fugacities by rain underscores its relevance, explaining the occurrence of organic pollutants in environments across different climatic regions.

Prognostic role of cardiac magnetic resonance in left ventricular noncompaction

Funding Acknowledgements

Type of funding sources: None.

Background

Left ventricular noncompaction (LVNC) is a heterogeneous entity with a wide phenotypic expression. Risk factors have not been well established and prognostic stratification remains challenging.

Purpose

Describe prognostic role of CMR on long term outcomes of LVNC patients. 

Methods

 

Retrospective multicentric longitudinal cohort study of consecutive patients fulfilling imaging diagnostic criteria for LVNC (Jenni echo criteria and Petersen and Jacquier CMR criteria). Demographic, ECG, genetic, family and treatment variables were recorded. Baseline CMR was used for the analysis. LV ejection fraction (LVEF) was categorized according to heart failure (HF) guidelines and late gadolinium enhancement (LGE) was visually assessed in a binary way. End points were HF, ventricular arrhythmias (VA), systemic embolisms (SE) and all-cause death. Major adverse cardiovascular events (MACE) were the combination of the four previous end points. In patients with initially preserved LVEF (≥ 50%), LV adverse remodelling (LVAR) was defined as an LVEF < 50% and/or absolute decrease of ≥10% in LVEF at last follow-up.

Results

585 patients from 12 referral centres were included from 2000 to 2018. Age at diagnosis was 45 ± 20 years, 334 (57%) were male, baseline LVEF was 48 ± 17% and 18% presented LGE. During a median follow-up of 5.1 years (IQR 2.3-8.1), 110 (19%) patients presented HF, 87 (15%) VA, 18 (3%) SE and 34 (6%) died. MACE occurred in 223 (38%) patients.

LVEF was independently associated with HF, VA, SE and MACE: HR were 1.08, 1.02, 1.04 and 1.02 respectively (all p < 0.05). LGE was more frequent in patients with reduced LVEF (39 Vs 53%, p < 0.001) and was associated with higher HF and VA risk in patients with an LVEF > 35% (HR 2.69 and 2.48 respectively, p < 0.05) (Figure 1). No MACE (0%) occurred during long-term follow-up in patients with preserved LVEF, no LGE as well as no ECG abnormalities and no family aggregation.

305 (52%) patients presented with initially preserved LVEF, and 230 (75%) of those had LVEF available at last follow-up. LVAR occurred in 50 (22%) patients: 22 (10%) had an LVEF < 50% and 41 (18%) an absolute ≥ 10% decrease in LVEF. LGE was independently associated with LVAR (HR 3.51, p = 0.045) (Figure 2). 

Conclusions

Cardiac magnetic resonance has an important prognostic role in LVNC. LVEF is the most powerful predictor of events. Myocardial fibrosis is associated with worse outcomes in patients without severe systolic dysfunction, as well as with left ventricular adverse remodelling in those with initially preserved LVEF. Besides, CMR may identify a low-risk subgroup of LVNC patients. Therefore, CMR should be used in risk stratification in LVNC.

Long term outcomes in left ventricular noncompaction

Funding Acknowledgements

Type of funding sources: None.

Background

Left ventricular noncompaction (LVNC) is a heterogeneous entity with a wide phenotypic expression. Risk factors have not been well established and prognostic stratification remains challenging.

Objectives

Describe long term outcomes of LVNC patients and determine predictors of cardiovascular events. 

Methods

 

Prospective multicentric study of consecutive patients fulfilling imaging diangostic criteria for LVNC (Jenni echo criteria and Petersen CMR criteria). Demographic, ECG, imaging and genetic variables were collected. End points were heart failure (HF), ventricular arrhythmias (VA), systemic embolisms (SE) and all-cause death. Major adverse cardiovascular events (MACE) was the combination of the four previous end points.

Results

585 patients from 12 referral centres were included from 2000 to 2018. Age at diagnosis was 45 ± 20 years, 334 (57%) were male, baseline LVEF was 48 ± 17% and 18% presented late gadolinium enhancement (LGE). During a median follow-up of 5.1 years (IQR 2.3-8.1), 110 (19%) patients presented HF, 87 (15%) VA, 18 (3%) SE and 34 (6%) died. MACE occurred in 223 (38%) patients.

LVEF was independently associated with HF, VA, SE and MACE: HR were 1.08, 1.02, 1.04 and 1.02 respectively (all p < 0.05). LGE was more frequent in patients with reduced LVEF (39 Vs 53%, p < 0.001) and was associated with higher HF and VA risk in patients with LVEF > 35% (HR 2.69 and 2.48 respectively, p < 0.05) (Figure 1). Patients with a normal ECG, LVEF≥50%, no LGE and no family aggregation presented no MACE (0%) at long term follow-up.

Among patients who underwent genetic testing (354, 61%), TTN variants and complex genotype (more than one variant) presented lower LVEF and higher HF risk. ACTC1 variants were associated with VA.

Conclusions

LVNC carries a high long term risk of heart faliure and ventricular arrhythmias. LVEF is the most important predictor and myocardial fibrosis is associated with increased risk in patients without severe systolic dysfunction. Genotype is a modifier of outcomes. These factors might be used to risk stratify LVNC patients.

Abstract Figure. Kaplan Meier survival curves

Enrichment of perfluoroalkyl substances in the sea-surface microlayer and sea-spray aerosols in the Southern Ocean

Sea-spray (or sea-salt) aerosol (SSA) formation and their subsequent atmospheric transport and deposition have been suggested to play a prominent role in the occurrence of ionizable perfluoroalkyl substances (PFAS) in the maritime Antarctica and other remote regions. However, field studies on SSA's role as vector of transport of PFAS are lacking. Following a multiphase approach, seawater (SW), the sea-surface microlayer (SML) and SSA were sampled simultaneously at South Bay (Livingston Island, Antarctica). Average PFAS concentrations were 313 pg L^-1, 447 pg L^-1, and 0.67 pg m^-3 in SW, the SML and SSA, respectively. The enrichment factors of PFAS in the SML and SSA ranged between 1.2 and 5, and between 522 and 4690, respectively. This amplification of concentrations in the SML is consistent with the surfactant properties of PFAS, while the large enrichment of PFAS in atmospheric SSA may be facilitated by the large surface area of SSA and the sorption of PFAS to aerosol organic matter. This is the first field work assessing the simultaneous occurrence of PFAS in SW, the SML and SSA. The large measured amplification of concentrations in marine aerosols supports the role of SSA as a relevant vector for long-range atmospheric transport of PFAS.

Are aortic root and ascending aorta echocardiographic diameters by adult vs paediatric guidelines recommendations interchangeable?

Background

Both aortic root size and ascending aorta are clinical parameters with significant therapeutic implications which can be easily assessed by transthoracic echocardiography (TTE). However, measurement values may vary according to cardiac cycle and the edge convention used.

Purpose

This study aimed to compare the aortic diameter values measured using the lastest recommendations of two different guidelines, adults and children, to determine the influence of these methods on echocardiographic measurements.

Methods

Two hundred and fifty adult patients (56% male, 63±15 years of age) and 67 children (65% male, 10.04±4.5 years of age) in whom TTE was clinically indicated were included. Aortic diameters were measured twice at 2 levels (sinuses of Valsalva and ascending aorta): leading edge to leading edge during diastole, (L-L in D) following the 2015 American Society of Echocardiography (ASE) adults guidelines and inner edge to inner edge during systole (I-I in S) following the 2010 ASE paediatric guidelines.

Results

Mean aortic diameters obtained by L-L in D and I-I in S are shown in Table 1. Correlation coefficient was 0.990 (CI95% 0.988–0.992) for sinuses of Valsalva measurements and 0.991 (CI95% 0.989–0.993) for ascending aorta in adult patients and 0.983 (CI95% 0.975–0.973) and 0.970 (CI95% 0.956–0.952) in childrens respectively. When both populations were analysed together, concordance correlation coefficients were 0.991 (CI95% 0.989–0.993) and 0.970 (CI95% 0.991–0.994), respectively. Bland- Altman analysis for each level measured (A: aortic root; B: ascending aorta) in the total cohort of 317 patients is shown in Figure 1. Mean aortic diameters and differences in the whole group are shown in Table 1.

Conclusions

Measurement of aortic root and ascending aorta showed a significantly larger diameters by L-L in D than by I-I in S. However, these differences had subclinical significance and management implications. These similar diameter values may be used indifferently but systematically during follow-up. Systolic diameter expansion has a similar value to that of anterior aortic wall thickness; however, it is more vulnerable to changes in haemodynamic conditions.

Figure 1

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Vall d'Hebron Research Institute

Long term outcomes in left ventricular non-compaction

Background

Left ventricular non-compaction (LVNC) is a highly heterogeneous entity with a wide phenotypic expression. Risk factors have not been well established and prognostic stratification remains challenging.

Objectives

Describe long term outcomes of LVNC patients and determine predictors of cardiovascular events.

Methods

Prospective multicentric study of consecutive patients fulfilling imaging criteria for LVNC. Demographic, ECG, imaging and genetic variables were collected. End points were heart failure (HF), ventricular arrhythmias (VA), systemic embolisms (SE) and all-cause death. Major adverse cardiovascular event (MACE) was described as the combination of the four previous end points.

Results

592 patients from 13 referral centres were included from 2000 to 2018. Mean age at diagnosis was 45 years, 252 (43%) were female and mean LVEF was 48% (Table 1). During a median follow-up of 55 months (IQR 24–90), 144 (25%) patients presented HF, 101 (18%) VA, 27 (5%) SE and 33 (6%) died. MACE occurred in 223 (39%) patients.

In multivariate analysis, independent predictors of HF were LVEF (OR 0.9), PSAP (OR 1.17) and late gadolinium enhancement (LGE) (OR 1.3). VA were independently associated with LVEF (OR 0.97) and LGE (OR 2.51). Independent predictors of SE were LVEF (OR 0.96) and LA diameter (OR 1.07). No independent predictors of all-cause death could be described. MACE were independently associated with LVEF (OR 1.04) and PSAP (OR 1.08) (Table 1).

Among patients who underwent genetic testing (340, 57%), genotype was associated with outcomes: MYH7 and ACTC1 variants were protective while multiple mutations, TTN and MYBPC3 variants exhibited worse prognosis.

Conclusions

In a large prospective multicentric cohort of LVNC patients, there was a moderate long term incidence of cardiovascular events. LVEF and fibrosis were the main predictors and genotype was a modifier of outcomes. These factors might be used to risk stratify LVNC patients.

Funding Acknowledgement

Type of funding source: None

Sources and diffusive air-water exchange of polycyclic aromatic hydrocarbons in an oligotrophic North-Patagonian lake

Polycyclic aromatic hydrocarbons (PAHs) are semivolatile organic compounds of environmental concern. This study aims to investigate the influence of local sources of anthropogenic PAHs and their air-water exchange fluxes in an oligotrophic North-Patagonian lake in Chile. The monitoring was carried out in Panguipulli Lake during a six-month period during the autumn and winter seasons (March to August 2017) using a high-volume air sampler and a pump system for water samples. We detected and quantified fifteen PAHs in the gas phase (mean ∑₁₅PAHs = 11.6 ng m^-3) and dissolved water phase (mean ∑₁₅PAHs = 961.8 pg L^-1). Methylphenanthrenes and pyrene dominated the concentrations of PAHs in the studied phases. To determine sources of PAHs we used the PAH ratios of Light Molecular Weight/Heavy Molecular Weight (∑LMW/∑HMW) and Phenanthrene/Anthracene (Phe/Ant). The PAH ratio results revealed a pyrogenic source. We estimated the air-water diffusive exchange fluxes and fugacity ratios for the studied compounds. In general, air-water diffusive exchanges of PAHs showed a net volatilization for the less hydrophobic (log K_OW < 4) and lighter PAHs (MW ≤ 170 g mol^-1), and a net deposition trend for the more hydrophobic (log K_OW 4-7) and higher molecular weight PAHs (MW ≥ 178 g mol^-1). We found a significant correlation between log water/air fugacity ratios and log K_OW of PAHs. Therefore, it is suggested that this oligotrophic lake acts as a sink by accumulating hydrophobic and mid-high molecular weight PAHs derived mainly from pyrogenic sources. This study is the first attempt to understand the sources and behavior of PAHs in oligotrophic lakes in the Southern Chile where information is scarce regarding the occurrence of PAHs.

Large Enrichment of Anthropogenic Organic Matter Degrading Bacteria in the Sea-Surface Microlayer at Coastal Livingston Island (Antarctica)

The composition of bacteria inhabiting the sea-surface microlayer (SML) is poorly characterized globally and yet undescribed for the Southern Ocean, despite their relevance for the biogeochemistry of the surface ocean. We report the abundances and diversity of bacteria inhabiting the SML and the subsurface waters (SSL) determined from a unique sample set from a polar coastal ecosystem (Livingston Island, Antarctica). From early to late austral summer (January–March 2018), we consistently found a higher abundance of bacteria in the SML than in the SSL. The SML was enriched in some Gammaproteobacteria genus such as Pseudoalteromonas, Pseudomonas, and Colwellia, known to degrade a wide range of semivolatile, hydrophobic, and surfactant-like organic pollutants. Hydrocarbons and other synthetic chemicals including surfactants, such as perfluoroalkyl substances (PFAS), reach remote marine environments by atmospheric transport and deposition and by oceanic currents, and are known to accumulate in the SML. Relative abundances of specific SML-enriched bacterial groups were significantly correlated to concentrations of PFASs, taken as a proxy of hydrophobic anthropogenic pollutants present in the SML and its stability. Our observations provide evidence for an important pollutant-bacteria interaction in the marine SML. Given that pollutant emissions have increased during the Anthropocene, our results point to the need to assess chemical pollution as a factor modulating marine microbiomes in the contemporaneous and future oceans.

P1441 Predictors of systemic embolisms in a large cohort of left ventricular noncompaction patients

BACKGROUND

Left ventricular noncompaction (LVNC) is associated with an increased risk of systemic embolisms (SE). However, incidence and risk factors are not well established.

PURPOSE

To evaluate the rate of SE in LVNC and describe risk factors.

METHODS

LNVC patients were included in a multicentric registry. Those with SE were considered for the analysis.

RESULTS

514 patients with LVNC from 10 Spanish centres were recruited from 2000 to 2018. During a median follow-up of 4.2 years (IQR 1.9-7.1), 23 patients (4.5%) had a SE. Patients with SE (Table 1) were older at diagnosis, with no differences in gender and had similar cardiovascular risk factors. They were more frequently under oral anticoagulation (OAC). Besides, they had a more reduced LVEF, and more dilated LV and left atrium (LA). Late gadolinium enhancement (LGE) was more frequent, altogether suggesting a more severe phenotype.

Patients with SE had non-significantly higher rates of hospitalization for heart failure (33% Vs 24%, p = 0.31) and atrial fibrillation (35% Vs 19%, p = 0.10). In multivariate analysis, only LA diameter was an independent predictor of SE (OR 1.04, p = 0.04). A LA diameter &gt; 45 mm had an independent 3 fold increased risk of SE (OR 3.04, p = 0.02) (Image 1).

CONCLUSIONS

LVNC carries a moderate mid-term risk of SE, which appears to be irrespective of atrial fibrillation and associated with age, LV dilatation and systolic dysfunction and mainly LA dilatation. This subgroup of patients should be considered for oral anticoagulation in primary prevention.

Table 1 Systemic embolisms (n = 23) No systemic embolisms (n = 491) p Men, n (%) 15 (65) 289 (56) 0.52 Median age at diagnosis (IQR) - yr 60 (48-76) 48 (30-64) 0.02 Median follow up (IQR) - yr 5.9 (3.1-7.8) 4.2 (1.8-7.1) 0.18 OAC, n (%) 19 (83) 118 (24) 0.01 LVEF (SD) - % 37 (15) 48 (17) 0.01 LVEDD (SD) - mm 58 (11) 54 (10) 0.04 LA diameter (SD) - mm 46 (9) 39 (9) 0.01 Characteristics of patients with and without systemic embolisms

Abstract P1441 Figure. Image 1

P1600 Aortic dilatation in patients with chronic descending aorta dissection is related to maximum false-lumen systolic flow deceleration rate as evaluated by 4D-flow MRI

Background

Due to improved surgical strategies a growing number of patients survive acute aortic dissection. Patent false lumen (FL) is common in chronic dissection and it has been associated with poor prognosis, which is mainly driven by FL expansion. Several variables indirectly related to flow characteristics have been associated with progressive aortic dilation. We aimed to evaluate whether the maximum systolic flow deceleration rate (MSDR) in the FL, quantified by 4D-flow MR, is related to FL dilation in chronic type B aortic dissection.

Methods

Twenty-nine patients with a patent FL after aortic dissection and a prior follow-up of at least 3 years underwent contrast-enhanced 4D-flow MR. Marfan patients were excluded. Time-resolved FL flow acceleration was calculated in a 5 cm-long volume of the descending aorta around the level of the pulmonary bifurcation. MSDR was determined as the maximum minus the minimum acceleration in systole over the corresponding time interval (Figure 1a). Aortic growth rate (GR) was measured as the difference between final and initial maximum FL diameters obtained by angio-CT divided by follow-up duration. Population was divided into tertiles based on GR.

Results

Demographic and clinical variables were similar among GR tertiles (Table). MSDR was lower in patients with a GR &lt;1mm/year (group 1) compared to both the other two patient groups (p = 0.009 and 0.003 for groups 2 and 3, respectively) (Figure 1c). MSDR showed a marked positive linear correlation with GR (R = 0.481, p = 0.008) (Figure 1b).

Conclusions

The MSDR in the FL of chronic type B aortic dissection is linearly related to FL growth rate and discriminated between tertiles of aortic dilation. Prospective longitudinal studies are need to unveil possible prognostic value of this parameter.

Table Group 1 (n = 9) Group 2 (n = 10) Group 3 (n = 10) p-value Age (years) 63.44 ±13.54 62.50 ± 13.60 64.56 ± 6.67 0.902 BSA (m2) 2.00 ± 0.18 1.77 ± 0.20 1.94 ± 0.12 0.213 Men 6 (86%) 4 (57%) 4 (100%) 0.210 Hypertension 4 (66%) 5 (71%) 4 (100%) 0.438 Atheroclerosis 1 (17%) 1 (14%) 0 (0%) 0.699 Initial Diameter (mm) 45.00 ± 7.69 36.00 ± 4.20 37.00 ± 6.48 0.078 Final Diameter (mm) 49.50 ± 6.74 44.86 ± 5.70 59.25 ± 9.84 0.049 Follow-up (year) 11.83 ± 8.79 7.82 ± 3.34 8.08 ± 4.05 0.921 GR (mm/year) 0.27 ± 0.29 1.18 ± 0.26 2.64 ± 0.97 &lt;0.001 MSDR (cm/s3) 1212.18 ± 467.61 2410.54 ± 1034.30 2558.16 ± 1098.06 0.005

Abstract P1600 Figure 1

P1442 Outcomes of patients with left ventricular noncompaction and preserved ejection fraction

CONCLUSIONS

Patients with LVNC and pEF have an overall excellent prognosis, which is markedly better than those with rEF. However, there is progressive decrease in LVEF, associated with heart failure, and moderate risk of life threatening arrhythmias. Therefore, periodic follow-up should be promoted.

Table 1 LVNC pEF (n = 239) LVNC rEF (n = 252) p Men, n (%) 131 (55) 146 (58) 0.65 Median age at diagnosis (IQR) - yr 38 (23-54) 58 (42-72) 0.01 Median follow up (IQR) - yr 4.9 (2.1-7.3) 3.9 (1.4-7.9) 0.04 QRS (SD) - ms 93 (18) 117 (32) 0.01 LGE, n (%) 18 (9) 52 (30) 0.01

Abstract P1442 Figure. Image 1

P1827Maximum systolic flow deceleration rate in the false lumen by 4D-flow MRI is associated with aortic dilatation in patients with chronic descending aorta dissection

Introduction

Patent false lumen (FL) in aortic dissection has been associated with poor prognosis mainly due to aortic expansion. Although morphologic variables have been related to aortic dilatation as expression of high pressure in the FL, they do not reflect flow characteristics. We propose the maximum systolic flow deceleration rate (MSDR) in the FL, quantified by 4Dflow, assuming that flow should be strongly decelerated during systole under high pressure.

Methods

Twenty-nine patients with a patent FL after aortic dissection (no Marfan syndrome) and with a follow-up of at least 3 years underwent a contrast-enhanced 4D-flow MR. FL acceleration was calculated during the cardiac cycle in a sub-volume of the descending aorta (5 cm around the level of the pulmonary bifurcation). MSDR was determined as the maximum minus the minimum acceleration in systole over the corresponding time interval (Figure 1a). Aortic growth rate (GR) was defined as the difference between final and initial aortic diameters obtained by angio-CT over the period of follow-up. Population was divided into tertiles based on GR.

Results

Demographic, clinical variables or basal aortic diameter did not show differences among GR groups (Table 1). MSDR was statistically different in patients with a GR <1mm/year (group 1) compared to fast-dilating patients (groups 2, 3) (Figure 1c). MSDR showed a positive linear correlation with GR resulting in a Pearson's correlation of 0.481 (p=0.008) (Figure 1b).

Table 1. Demographic and other variables Tertile 1 Tertile 2 Tertile 3 p-value Age (year) 63.4 (±13.5) 62.5 (±13.6) 64.6 (±6.7) 0.902 BSA (m2) 2.0 (±0.2) 1.8 (±0.2) 1.9 (±0.1) 0.213 Men 6 (86%) 4 (57%) 4 (100%) 0.210 Hypertension 4 (66%) 5 (71%) 4 (100%) 0.438 Atherosclerosis 1 (17%) 1 (14%) 0 (0%) 0.699 Initial diameter 45.0 (±7.69) 36.0 (±4.2) 37.0 (±6.5) 0.078 Final diameter 49.5 (±6.74) 44.9 (±5.7) 59.2 (±9.8) 0.049* Follow-up (year) 11.8 (±8.79) 7.9 (±3.3) 8.1 (±4.0) 0.921 Aortic GR (mm/year) 0.3 (±0.3) 1.2 (±0.3) 2.6 (±1.0) 0.001* MSDR (cm/s3) 1212 (±468) 2411 (±1034) 2558 (±1098) 0.005* Values are mean (±SD) or n (%).

Conclusion

MSDR of flow in the FL derived from 4D-flow RM is related to GR of dissected descending aorta. It is useful to discriminate mild vs. significant aorta enlargement and identify patients who may benefit from earlier therapy.

P5555Predictors of systemic embolisms in a large cohort of left ventricular noncompaction patients

Background

Left ventricular noncompaction (LVNC) is associated with an increased risk of systemic embolisms (SE). However, incidence and risk factors are not well established.

Purpose

To evaluate the rate of SE in LVNC and describe risk factors.

Methods

LNVC patients were included in a multicentric registry. Those with SE were considered for the analysis.

Results

514 patients with LVNC from 10 Spanish centres were recruited from 2000 to 2018. During a median follow-up of 4.2 years (IQR 1.9–7.1), 23 patients (4.5%) had a SE. Patients with SE (Table 1) were older at diagnosis, with no differences in gender and had similar cardiovascular risk factors. They were more frequently under oral anticoagulation (OAC). Besides, they had a more reduced LVEF, and more dilated LV and left atrium (LA). Late gadolinium enhancement (LGE) was more frequent, altogether suggesting a more severe phenotype.

Patients with SE had non-significantly higher rates of hospitalization for heart failure (33% vs 24%, p=0.31) and atrial fibrillation (35% vs 19%, p=0.10). In multivariate analysis, only LA diameter was an independent predictor of SE (OR 1.04, p=0.04). A LA diameter>45 mm had an independent 3 fold increased risk of SE (OR 3.04, p=0.02) (Image 1).

Table 1 Systemic embolisms (n=23) No systemic embolisms (n=491) p Men, n (%) 15 (65) 289 (56) 0.52 Median age at diagnosis (IQR), yr 60 (48–76) 48 (30–64) 0.02 Median follow up (IQR), yr 5.9 (3.1–7.8) 4.2 (1.8–7.1) 0.18 Hypertension, % 8 (33) 118 (24) 0.31 Diabetes mellitus, % 3 (14) 39 (8) 0.41 OAC, % 19 (83) 118 (24) 0.01 LVEF (SD), % 37 (15) 48 (17) 0.01 LVEDD (SD), mm 58 (11) 54 (10) 0.04 LVESD (SD), mm 45 (13) 38 (11) 0.01 LA diameter (SD), mm 46 (9) 39 (9) 0.01 LVEDV CMR (SD), mL 193 (75) 163 (70) 0.12 LVESV CMR (SD), mL 121 (64) 85 (64) 0.04 LGE, % 9 (40) 88 (18) 0.04

Conclusions

LVNC carries a moderate mid-term risk of SE, which appears to be irrespective of atrial fibrillation and associated with age, LV dilatation and systolic dysfunction and mainly LA dilatation. This subgroup of patients should be considered for oral anticoagulation in primary prevention.

4936Cardiac magnetic resonance strain analysis predicts functional recovery following acute ST-segment elevation myocardial infarction

Background

Late gadolinium enhancement (LGE) is the clinical reference standard for estimation of infarct extension and prediction of functional recovery following reperfused acute ST-segment elevation myocardial infarction (STEMI). Nevertheless, myocardial edema, microvascular obstruction and intramyocardial hemorrhage as well as the timing of image acquisition after contrast administration may influence the extent of LGE and underestimate the potential for recovery. Dobutamine stress testing has been recommended to more accurately predict functional recovery when infarct transmurality is between 25 to 75%. We hypothesized that cardiac magnetic resonance (CMR) tissue tracking strain analysis may provide additional value to LGE for the prediction of functional recovery.

Methods

In 370 patients with STEMI who underwent successful primary percutaneous revascularization and were studied with CMR within 3–5 days of the event, peak systolic longitudinal (LS), circumferential (CS) and radial (RS) strain were analyzed with routine SSFP images of 3 long-axis and a stack of short-axis slices (Tissue Tracking, CVI42®, Figure panel A and B). Inversion-recovery echogradient sequences were analyzed 20 minutes after contrast administration for LGE transmurality (Panel C). All per-segment analysis was performed according to the AHA 16-segment model. CMR was repeated at 6 months and functional recovery was defined as persistent normokinesia or improvement of wall motion score from baseline to 6-month CMR.

Results

At baseline CMR, of a total of 5920 segments 70.4% were normokinetic, 7.2% were hypokinetic, 21.9% were akinetic and 0.6% were dyskinetic. All strain parameters decreased significantly with worsening wall motion. At follow-up, 81.5% of the segments showed functional recovery. All strain parameters were significantly associated with functional recovery (p<0.001) and showed higher predictive value for improvement of wall motion than LGE transmurality (ROC AUC 0.713 LS, 0.710 CS, 0.683 RS and 0.660 LGE). For basal CMR dysfunctional segments, a CS <−10.7% showed the highest accuracy (66%) to predict wall motion improvement, with 58% sensitivity, 76% specificity, 75% positive predictive value (PPV) and 59% negative predictive value (NPV). These results were comparable to LGE transmurality <50% (65% accuracy, 59% sensitivity, 73% specificity, 74% positive predictive value and 58% negative predictive value). Nevertheless, adding CS analysis to a 50% LGE transmurality cutoff was the best combination for prediction of functional recovery and increased the overall accuracy to 70%, with 76% sensitivity, 64% specificity, 65% PPV and 75% NPV.

CS analysis in an inferior STEMI

Conclusions

Acute CMR tissue tracking strain analysis complements LGE assessment for prediction of functional recovery following an STEMI. The combination of LGE infarct transmurality under 50% and a CS strain higher than −10.7% showed the highest accuracy for prediction of recovery of function.

Snow Amplification of Persistent Organic Pollutants at Coastal Antarctica

Many legacy and emerging persistent organic pollutants (POPs) have been reported in polar regions, and act as sentinels of global pollution. Maritime Antarctica is recipient of abundant snow precipitation. Snow scavenges air pollutants, and after snow melting, it can induce an unquantified and poorly understood amplification of concentrations of POPs. Air, snow, the fugacity in soils and snow, seawater and plankton were sampled concurrently from late spring to late summer at Livingston Island (Antarctica). Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) concentrations in snow and air were close to equilibrium. POPs in soils showed concentrations close to soil-air equilibrium or net volatilization depending on chemical volatility. Seawater-air fugacity ratios were highly correlated with the product of the snow-air partition coefficient and the Henry's law constant (K_SA H'), a measure of snow amplification of fugacity. Therefore, coastal seawater mirrored the PCB congener profile and increased concentrations in snowmelt due to snowpack releasing POPs to seawater. The influence of snowpack and glacier inputs was further evidenced by the correlation between net volatilization fluxes of PCBs and seawater salinity. A meta-analysis of K_SA, estimated as the ratio of POP concentrations in snow and air from previously reported simultaneous field measurements, showed that snow amplification is relevant for diverse families of POPs, independent of their volatility. We claim that the potential impact of atmospheric pollution on aquatic ecosystems has been under-predicted by only considering air-water partitioning, as snow amplification influences, and may even control, the POP occurrence in cold environments.

Seasonal variations in the occurrence of perfluoroalkyl substances in water, sediment and fish samples from Ebro Delta (Catalonia, Spain)

The main objective of this study was to assess the concentration levels and the seasonal variations of 13 poly- and perfluoroalkyl substances (PFASs) in different compartments (water, sediments and fish) of the Ebro Delta (NE Spain) and surrounding coastal areas. Perfluorooctanoic acid (PFOA) was the most frequently detected compound in waters and sediments. Perfluorocarboxylic acids (PFCAs) were the compounds found at the highest concentrations in water samples. On the other hand, sediments were more enriched in perfluorooctanesulfonate (PFOS) (range<1.02-22.6ng/g dw). Waters and sediments showed a different seasonal trend. While waters were characterised by a substantial constant level of PFASs over the year, sediments showed a progressive decrease from autumn to summer, revealing the great influence that environmental conditions exert on PFAS distribution in sediments. As regards fish samples, in spite of the ban of its production, PFOS was the most frequently detected compound in seawater fishes, in agreement with its high persistency, bioaccumulation and biomagnification. Moreover, PFASs showed to be more distributed in the skin rather than in muscle tissues. In addition, river fishes were characterised by very high PFAS levels (∑PFAS range from 63.8ng/g ww to 938ng/g ww), with perfluoroalkyl carboxylic acids being more concentrated than sulfonates. The PFASs concentrations in water, sediment, and biota revealed that one of the studied sites, Isla de Buda was the most contaminated site of the Ebro Delta. These results are consistent with its location at the final part of the estuary, where many irrigation channels are collected together.

Litter assessment on 99 Cuban beaches: A baseline to identify sources of pollution and impacts for tourism and recreation

Litter presence was assessed on the entire Cuban coastline, and includes 99 beaches from all Cuban regions, during field work carried out in 2012 and 2015. A standard method verified in several countries was applied, which classified beaches for nine types of litter into four grades (A-excellent to D-poor). Almost half of the Cuban beaches obtained excellent cleanliness scores, although many needed to be better managed. In this baseline, the most common types of residue were general litter (8% grade D and 35% grades B/C) and potentially harmful litter (<68% with grade A). Resort beaches and those with international visitors showed the best litter management. Tourism Impacts seems to be related to visitor origin therefore choices to develop sustainable tourism in rural and village beaches (64%) appears low, if beach cleaning gross investment is focused on resort beaches (24%). Finally, this paper highlights geographical distribution and types of litter patterns.

Nuclear translocation of haeme oxygenase-1 is associated to prostate cancer

The role of oxidative stress in prostate cancer has been increasingly recognised. Acute and chronic inflammations generate reactive oxygen species that result in damage to cellular structures. Haeme oxygenase-1 (HO-1) has cytoprotective effects against oxidative damage. We hypothesise that modulation of HO-1 expression may be involved in the process of prostate carcinogenesis and prostate cancer progression. We thus studied HO-1 expression and localisation in 85 samples of organ-confined primary prostate cancer obtained via radical prostatectomy (Gleason grades 4–9) and in 39 specimens of benign prostatic hyperplasia (BPH). We assessed HO-1 expression by immunohistochemical staining. No significant difference was observed in the cytoplasmic positive reactivity among tumours (84%), non-neoplastic surrounding parenchyma (89%), or BPH samples (87%) (P=0.53). Haeme oxygenase-1 immunostaining was detected in the nuclei of prostate cancer cells in 55 of 85 (65%) patients but less often in non-neoplastic surrounding parenchyma (30 of 85, 35%) or in BPH (9 of 39, 23%) (P<0.0001). Immunocytochemical and western blot analysis showed HO-1 only in the cytoplasmic compartment of PC3 and LNCaP prostate cancer cell lines. Treatment with hemin, a well-known specific inducer of HO-1, led to clear nuclear localisation of HO-1 in both cell lines and highly induced HO-1 expression in both cellular compartments. These findings have demonstrated, for the first time, that HO-1 expression and nuclear localisation can define a new subgroup of prostate cancer primary tumours and that the modulation of HO-1 expression and its nuclear translocation could represent new avenues for therapy.

Neutrophilic eccrine hidradenitis secondary to topotecan

BACKGROUND

Neutrophilic eccrine hidradenitis (NEH) is a self-restricted inflammatory condition, usually secondary to chemotherapeutic agents and less frequently to other drugs such as zidovudine or various infections. NEH clinical features include erythematous, occasionally painful nodules and plaques. Histological examinations reveal neutrophilic infiltrates and degeneration of eccrine glands.

METHODS

A 45-year-old female was treated with topotecan and colony-stimulating factor for ovarian cancer.

RESULTS

The erythematous and slightly pruritic plaques on the upper and lower limbs and ear lobes appeared approximately 1 week after chemotherapy and spontaneously subsided in about 10 days, only to recur after the next drug dose. A skin biopsy revealed NEH; all skin cultures were negative.

CONCLUSION

It is believed that this patient developed topotecan-induced NEH; this relationship with therapy rather than the underlying disease rules out a paraneoplastic reaction, and negative cultures excluded infectious causes. In addition, since skin lesions recurred after CSF was discontinued, this agent was not involved. Studies relating NEH to topotecan, a topoisomerasa I inhibitor, have not reported such an event in the literature.

Cytomegalovirus maculopapular eruption in a kidney transplant patient

Cytomegalovirus (CMV) is the most important viral agent in kidney transplantation. Clinical manifestations of CMV disease in transplantation include hepatitis, pneumonitis, pancreatitis, kidney allograft dysfunction, colitis, and meningoencephalitis. However, skin involvement is rare. We describe a severely compromised cadaveric-kidney transplant recipient who developed renal failure, colonic ulcers, and a maculopapular rash accompanied by fever and malaise 4 months after transplantation. Only the skin biopsy was diagnostic and consistent with CMV disease. Intravenous ganciclovir administration resulted in clinical improvement of CMV-induced skin lesions; kidney function normalized and the patient became asymptomatic after 14 days of ganciclovir therapy. Nephrologists should consider the diagnosis of CMV disease in the febrile immunosuppressed patient with skin involvement. Skin biopsy must be considered as a useful and safe procedure in patients with a rash to obtain a prompt diagnosis and efficiently treat this immunocompromised population.

Anaesthetic management of the surgical separation of a pair of thoracopagus-cardiopagus twins

We describe the anaesthetic management of the surgical separation of a pair of thoracopagus-cardiopagus twins with a common right atrium and a myocardial tissue bridge containing vascular channels between their ventricles. One of them died during the procedure, the surviving twin is now two years old. The survival of one twin for two years without significant sequelae, after the surgical separation of twins with shared right atrium and fused ventricles, has not previously been reported. Careful preoperative assessment is essential to anticipate potential serious problems during the procedure.