Rerouting of a major shipping lane through important harbour porpoise habitat caused no detectable change in annual occurrence or foraging patterns

Shipping is one of the largest industries globally, with well-known negative impacts on the marine environment. Despite the known negative short-term (minutes to hours) impact of shipping on individual animal behavioural responses, very little is understood about the long-term (months to years) impact on marine species presence and area use. This study took advantage of a planned rerouting of a major shipping lane leading into the Baltic Sea, to investigate the impact on the presence and foraging behaviour of a marine species known to be sensitive to underwater noise, the harbour porpoise (Phocoena phocoena). Passive acoustic monitoring data were collected from 15 stations over two years. Against predictions, no clear change occurred in monthly presence or foraging behaviour of the porpoises, despite the observed changes in noise and vessel traffic. However, long-term heightened noise levels may still impact communication, echolocation, or stress levels of individuals, and needs further investigation.

Burden of morbidity in patients with Ebstein anomaly: a two-country, population-based cohort study including 823 patients

Background

Burden of morbidity in patients with Ebstein anomaly (EA) is to a large extent undescribed.

Purpose

We conducted an extensive two-country register-based collaboration aiming to describe the burden of morbidity in patients with EA.

Methods

Patients born in the period 1930–2017 and diagnosed with EA were identified in Danish and Swedish nationwide medical registries and subsequently merged. Each EA patient was matched by birth year and gender with ten controls without congenital heart disease from the general population. Cox proportional hazard regression model was used to compute risk (hazard ratio (HR)) of morbidity (arrhythmia, heart failure, and stroke). Follow-up started at birth. Patients and controls became at risk at birth.

Results

We included 823 patients and 8,230 matched controls; median follow-up was 13.2 years (interquartile range: 3.5–20.9). In the total EA cohort, 44% (n=366) underwent cardiac surgery, predominantly EA-related surgery (81%) and other congenital cardiac surgery (15%). Approximately half of the cohort had an isolated EA (n=442) and 13% (n=108) had a concomitant atrial septal defect (ASD) only. Patients with non-operated isolated EA had a 9-fold increased risk of arrhythmia and a 5-fold increased risk of heart failure compared with the general population [HR for arrhythmia 9.4 (95% CI: 6.9–12.7) and HR forheart failure 5.2 (95% CI: 3.2–8.3)]. The risk of arrhythmia, heart failure, and stroke among patients with non-operated EA and concomitant ASD was 12.1 (95% CI: 3.0–48.8), 30.6 (95% CI: 3.2–295.2), and 8.2 (95% CI: 0.7–91.2), respectively. The risk of stroke in operated EA patients with concomitant ASD was 43.8 (95% CI: 17.5–109.7). Patients with operated isolated EA had a 25-fold increased risk of developing arrhythmia and 10-fold increased risk of heart failure compared with the general population [HR for arrhythmia 25.0 (95% CI: 17.7–35.3) and HR for heart failure 10.1 (95% CI: 6.0–16.9].

Conclusion

Patients with EA carries a substantial burden of arrhythmia, heart failure, and stroke compared with the general population irrespective of treatment pathway, necessitating meticulous follow-up in specialized adult congenital heart disease clinics to detect and possibly prevent or limit morbidity at an early stage.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Novo Nordic Foundation.

Mortality in patients with Ebstein anomaly: a two-country, population-based cohort study including 530 patients

Background

Low birth prevalence and referral bias constitutes significant obstacles in extending our knowledge regarding the natural history of Ebstein anomaly (EA).

Purpose

In an extensive two-country register-based collaboration we aimed to investigate the survival in EA patients with respect to associated congenital cardiac malformations

Methods

Patients born in the period 1970–2017 and diagnosed with EA were identified in Danish and Swedish nationwide medical registries and subsequently merged. Each EA patient was matched by birth year and gender with ten controls without congenital heart disease from the general population. Cox proportional hazard regression model and Kaplan-Meier survival function were used to compute risk of mortality (hazard ratio) and survival. Follow-up started at birth and patients became risk at time of EA diagnosis.

Results

We included 530 patients and 5,300 matched controls; median follow-up was 10.5 years (interquartile range: 3.5–20.9). In the total EA cohort, 43% (n=228) underwent cardiac surgery, predominantly EA-related surgery (81%). Approximately half of the cohort had an isolated EA (n=248), 11% (n=57) had a concomitant atrial septal defect only, and 42% (n=225) other associated congenital cardiac malformations. The 35-year survival in patients with isolated EA was 93%, superior compared with patients with concomitant atrial septal defect (ASD) (83%) and patients with other associated congenital cardiac malformations (72%), Figure 1. Patients with isolated non-operated EA had a risk of mortality of 25.6 (95% confidence interval (CI): 9.0–72.6) compared with the general population. Correspondingly, the risk in patients with surgically managed isolated EA was 21.7 (95% CI: 3.9–118.5). Patients with non-operated EA and a concomitant ASD (only) revealed a 10-fold increased risk of mortality (95% CI: 1.5–75.1) compared with the general population. The risk of mortality was substantially higher in both non-operated and operated EA patients with other associated congenital cardiac malformations, HR of 106.3 (95% CI: 31.8–335.4) and 42.6 (95% CI: 18.5–97.8), respectively.

Conclusions

Concomitant congenital cardiac malformations are common in EA patients and have major influence on survival, irrespective of treatment pathway (surgical versus non-surgical). Nonetheless, isolated non-operated EA patients have a 25-fold increased risk of mortality compared with the general population. Interestingly, concomitant ASD in non-operated patients seems protective in terms of risk of mortality.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Novo Nordisk Foundation.

Survival in patients with congenital heart disease and down syndrome

Background

Increasing survivorship among patients with congenital heart disease (CHD) has been reported during the past decades. However, a number of patients with CHD have an associated Down syndrome diagnosis and the long-term prognosis is still debated.

Purpose

The aim of the present study was to estimate the mortality risk in CHD patients with Down syndrome compared to a matched control population without CHD.

Methods

We linked data from the Swedish National Patient Register and Cause of Death Register to identify all CHD patients born between January 1970 and December 2017. Then we identified all CHD patients with Down syndrome. Each CHD patient with Down syndrome was matched for sex and birth year with eight controls without CHD or Down syndrome from the Total Population Register. A Cox proportional regression model was used to estimate the mortality risk and Kaplan Meier for survival analysis.

Results

In total, 3,285 patients with CHD and Down syndrome and 26,128 matched controls were identified. During a mean follow-up of 16.0 (±12.6) years, 558 CHD patients (17%) with Down syndrome, and 198 controls (0.76%) died. CHD patients with Down syndrome had 25.1 times higher risk of mortality (Hazard ratio 25.1, 95%, confidence interval (CI) 21.3–29.5) compared with controls. Patients with the most complex CHD were found to have the highest mortality risk (Hazard ratio 32.3, 95% CI 26.1–39.9). A decrease in risk of mortality during the first year of life was found between the two birth periods, risk of mortality was 46.8 (CI 29.5–74.0) in 1970–1989 and 17.7 (CI 12.8–24.42) 1990–2017. In addition, the mortality risk was two times (95% CI 1.94–2.31) higher for CHD patients with Down syndrome when compared to CHD patients without Down syndrome.

Conclusion

The risk of mortality among CHD patients with Down syndrome was 25 times higher compared to controls without CHD or Down syndrome. The highest risk of mortality was found in patients with complex CHD. The survivorship rate was exponentially increased in CHD patients with Down syndrome that were born after 1990, determining the modern era of congenital heart care.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish Government and county Councils (ALF)

Heart failure and long-term prognosis in patients with congenital heart disease: a nationwide, register-based cohort study

Introduction

Heart failure (HF) is associated with high morbidity and severe prognosis. The aim of this study was to investigate the risk of HF in patients with congenital heart disease (CHD) and to determine the prognosis after HF diagnoses in patients with CHD compared to HF controls without CHD.

Methods

We identified 89,532 patients with CHD born between 1930 and 2017 from the National Patient Register in Sweden and matched with 10 controls without CHD by gender and birth year from the National Population Register. The study population was followed-up until 2017, through the Swedish Patient Register and Cause of Death Register.

Results

Altogether, 7,013 (7.8%) patients with CHD and 9,681 (1.1%) controls developed HF. The overall incidence rate of HF was 31.6 per 104 person-years in patients with CHD and 4.0 per 104 person-years in controls. The mean age for HF diagnoses was 40.3 (± 28.8) in patients with CHD and 66.4 (± 13.6) for controls. The risk for developing HF was significantly higher in complex than non-complex CHD lesion groups, HR 28.7 (26.5–31.0) and HR 6.9 (6.7–7.2) respectively. Mortality incidence rate was twice as high in controls with HF compared to CHD with HF (IR 9.7 (9.4–10.0) and 4.74 (4.6–4.9), respectively). The mortality incidence was higher within all age groups except for 18–39 years and there was no difference between complex and non complex lesions

Conclusion

One out of thirteen CHD patients will develop HF. The highest risk for HF is within CHD patients with complex lesions. CHD patients develops HF at a considerably younger age, reflecting their slightly better prognosis after development of HF compared to controls with HF.

Funding Acknowledgement

Type of funding sources: None.

Ischemic stroke in patients with congenital heart disease and atrial fibrillation

Background

Atrial fibrillation (AF) is one of the most common arrhythmias in patients with congenital heart disease (CHD). The risk of developing AF is more than 20 times higher in patients with CHD compared with non-CHD controls. However, while it is known that young non-CHD patients with AF have a low risk for ischemic stroke (IS), little is known about the risk for IS young CHD patients with AF.

Purpose

To investigate the risk of developing IS in younger patients with CHD and AF compared to non-CHD control patients with AF.

Method

Using data from the National Swedish Patient Register and Cause of Death register, all CHD and born in Sweden between 1970 and 2017 with history of AF were identified. The Swedish total population register was used to identify age and sex matched controls. Among the matched controls, non-CHD patients AF were identified and used as reference group. CHD and non-CHD patients were followed from onset of AF until index IS, death or end of study (31st December 2017). Cox proportional hazard regression model with hazard ratio (HR) and 95% confidence interval (CI) was used to estimate the risk of IS in CHD patients with AF compared with non-CHD controls with AF.

Results

A total of 951 CHD with AF and 606 non-CHD controls with AF were identified. With ages ranging from 0 to 47 years, the median age was 25.6 and 30.7 years for CHD and non-CHD respectively. In patients with CHD and AF, 2.9% of patients (n=28) developed IS during follow up (mean follow up 34 years, SD ± 11.2), compared 0.5% (n=3) in non-CHD controls with AF (mean follow up 37 years, SD ± 9.5 years). The unadjusted HR for IS in CHD patients with AF compared with non-CHD controls with AF was 4.61 (95% CI1.39–15.25). When adjusted for age, sex, hypertension and heart failure, the risk of IS was more than five times higher (HR 5.16, 95% CI 1.52–17.46) in CHD patients compared with non-CHD patients. The adjusted HR for developing IS in non-complex CHD with AF compared with matched controls was 4.56 (95% CI 1.00–20.79). For patients born 1970–1989 the HR of IS was 7.35 (95% CI 1.70–31.75).

Conclusion

In this nationwide, register-based cohort study, the absolute number of IS among younger CHD patients with AF was relatively low. However, the risk for developing IS was more than 5 times higher compared to non-CHD patients with AF; highlighting the need of stroke score models in younger population, particularly to CHD patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish government and city Councils

Long-term mortality from birth in individuals with and without isolated congenital aortic stenosis: a nationwide, register-based cohort study

Background

Congenital aortic valve stenosis (CAVS) accounts for almost 5% of congenital heart defects. Increased survival has been reported in patients with complex congenital heart defects over the last decade. However, data on the long-term outcomes of simple defects such as in isolated CAVS, are still limited.

Purpose

The present study aimed to investigate the risk of mortality in patients with isolated CAVS over the last half century in Sweden.

Methods

We used data from the Swedish National Patient and Cause of Death Register to identify patients with isolated CAVS born between 1970 and 2017. Each CAVS was matched with 10 controls without congenital heart disease from the Total Population Register, according to sex and birth year. The maximal follow-up time was from birth up to 47.5 years of age. We estimated mortality rates for cases and controls, and the 95% confidence interval (CI) of their ratio. Kaplan-Meier curves were used to estimate the survival for cases and controls under the follow-up.

Results

A total of 1,258 patients with isolated CAVS and 12,550 matched controls were included in the study. The median follow-up was 24.5 years (interquartile range (IQR):18.0) for cases and 25.5 years (IQR: 17.6) for controls respectively. The overall risk of mortality was more than three times higher for patients with isolated CAVS, compared with matched controls, hazard ratio (HR) 3.1 (95%, CI 2.1–4.5). Survival at 47.5 years of age was 94.1% for cases and 97.3% for controls. Within the first year of life, the mortality risk in patients with isolated CAVS was more than 19 times higher (95%, CI 8.8–43.6) than controls. By contrast, when diagnosed with isolated CAVS above the age of 10 years, the risk of mortality was 2.1 times higher (95%, CI 1.1–3.5) compared to controls.

Conclusions

The mortality in patients with isolated CAVS was more than three times higher compared with matched controls. The highest mortality was found in patients with a diagnosis of isolated CAVS diagnosed within the first year after birth, verifying the critical form of the disease. Furthermore, patients diagnosed with isolated CAVS later in life (hence clinically assumed as a mild form of valvulopathy) have a mortality risk twice as high as controls, highlighting the need for follow-up and lifetime management, even in the mild forms of valvulopathies.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish Government and county Councils (ALF)

Chronic kidney disease in patients with congenital heart disease – a nationwide, register-based cohort study

Aims

To investigate the risk of chronic kidney disease (CKD) in young patients with congenital heart disease (CHD) (age 0–47 years) compared with age- and sex-matched controls without CHD.

Methods and results

Using data from the Swedish National Patient Register and the Cause of Death Register, 71,936 patients with CHD (50.2% male) born between 1970 and 2017 were identified. Each patient with CHD was matched by sex and age to 10 controls without CHD (n = 714,457). Follow-up data were collected for patients with CHD and controls until 2017. During a median follow-up of 13.5 (5.8; 25.5) years, 379 (0.5%) patients with CHD and 679 (0.1%) controls developed CKD. The risk of CKD was 6.4 times higher in patients with CHD than controls [95% confidence interval (CI): 5.65–7.27] and was highest in patients with severe non-conotruncal defects [hazard ratio (HR): 11.31; 95% CI: 7.37–17.36]. Compared with matched controls, the absolute and relative risks of CKD were greater for CHD patients born between 1997 and 2017 (HR: 9.98; 95% CI: 8.05–13.37) (incidence 39.5 per 100 000 person-years). The risk of CKD remained significantly higher after adjusting for hypertension, acute kidney injury, and diabetes mellitus (HR: 4.37; 95% CI: 3.83–5.00).

Conclusion

Although the absolute risk of CKD in young patients with CHD is relatively low, patients with CHD are six times more likely to develop CKD than non-CHD controls up to the age of 47 years. Further data are needed to inform guidelines on the prevention and follow-up of CKD in CHD patients.

Impacts of climate warming on reindeer herding require new land-use strategies

Climate in the Arctic has warmed at a more rapid pace than the global average over the past few decades leading to weather, snow, and ice situations previously unencountered. Reindeer herding is one of the primary livelihoods for Indigenous peoples throughout the Arctic. To understand how the new climate state forces societal adaptation, including new management strategies and needs for preserved, interconnected, undisturbed grazing areas, we coupled changes in temperature, precipitation, and snow depth recorded by automatic weather stations to herder observations of reindeer behaviour in grazing areas of the Laevas Sámi reindeer herding community, northern Sweden. Results show that weather and snow conditions strongly determine grazing opportunities and therefore reindeer response. We conclude that together with the cumulative effects of increased pressures from alternative land use activities, the non-predictable environmental conditions that are uniquely part of the warming climate seriously challenge future reindeer herding in northern Sweden.

Mortality in patients with isolated congenital complete atrioventricular block in Sweden: a register-based, nationwide cohort study

Purpose

The congenital heart block is a rare but potentially serious heart conduction disease and associated with high mortality during the fetal or neonatal periods. Earlier reports are based on relatively small number of patients and there are limited data about long-term outcomes.

Methods

Data were collected from the Swedish Patient and Cause of Death register to identify all patients who were born and diagnosed with isolated congenital complete atrioventricular block (CCAVB) between 1970 and 2017. Each patient with isolated CCAVB was matched with 10 control individuals, by birth year and sex from the Total Population Register.

Results

Totally 506 patients with CCAVB and 5,050 controls included in the study (55.3% males). The incidence rate of mortality in patients with isolated CCAVB was 166 per 10.000 person-years. The overall risk of mortality in patients with isolated CCAVB was 45.4 times (95% confidence interval (CI) 32.7–62.9) higher compared to matched controls. In a subgroup investigation, the highest risk of mortality was found in patients with isolated CCAVB from birth until the age of 17 (hazard ratio 80.8, 95% CI 51.6–126.4), compared to matched controls without CCAVB.

Conclusion

In this nationwide cohort study, patients with isolated CCAVB was associated with more than 40-fold risk for overall mortality compared to age and sex matched controls. The greatest risk was found during childhood. Regularly follow-up in tertiary centers and the aware of high risk of complications may be the key to prevention.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): The Swedish Government, the Swedish Research Council

Prenylcysteine oxidase 1, an emerging player in atherosclerosis

The research into the pathophysiology of atherosclerosis has considerably increased our understanding of the disease complexity, but still many questions remain unanswered, both mechanistically and pharmacologically. Here, we provided evidence that the pro-oxidant enzyme Prenylcysteine Oxidase 1 (PCYOX1), in the human atherosclerotic lesions, is both synthesized locally and transported within the subintimal space by proatherogenic lipoproteins accumulating in the arterial wall during atherogenesis. Further, Pcyox1 deficiency in Apoe^-/- mice retards atheroprogression, is associated with decreased features of lesion vulnerability and lower levels of lipid peroxidation, reduces plasma lipid levels and inflammation. PCYOX1 silencing in vitro affects the cellular proteome by influencing multiple functions related to inflammation, oxidative stress, and platelet adhesion. Collectively, these findings identify the pro-oxidant enzyme PCYOX1 as an emerging player in atherogenesis and, therefore, understanding the biology and mechanisms of all functions of this unique enzyme is likely to provide additional therapeutic opportunities in addressing atherosclerosis.

Allele frequency spectrum of known ankylosing spondylitis associated variants in a Swedish population

Objective: The genetic predisposition to ankylosing spondylitis (AS) has been most widely studied in cohorts with European ancestry. However, within Europe, disease prevalence is higher in Sweden. Given this, we aimed to characterize known AS susceptibility variants in a homogeneous Swedish data set, assessing reproducibility and direction of effect.Method: The power to detect association within an existing Swedish targeted sequencing study (381 controls; 310 AS cases) was examined, and a set of published associations (n = 151) was intersected with available genotypes. Association to disease was calculated using logistic regression accounting for population structure, and HLA-B27 status was determined with direct polymerase chain reaction genotyping.Results: The cases were found to be 92.3% HLA-B27 positive, with the data set showing ≥ 80% predictive power to replicate associations, with odds ratios ≥ 1.6 over a range of allele frequencies (0.1-0.7). Thirty-four markers, representing 23 gene loci, were available for investigation. The replicated variants tagged MICA and IL23R loci (p < 1.47 × 10^-3), with variable direction of effect noted for gene loci IL1R1 and MST1.Conclusion: The Swedish data set successfully replicated both major histocompatibility complex (MHC) and non-MHC loci, and revealed a different replication pattern compared to discovery data sets. This was possibly due to population demographics, including HLA-B27 frequency and measured comorbidities.

Sex Hormones in Men with Abdominal Aortic Aneurysm

BACKGROUND

Abdominal aortic aneurysm (AAA) primarily affects elderly men. The impact of sex on aneurysm development has been associated with an effect of sex hormones, through mechanisms that are not fully understood. This study aimed to examine the association between levels of sex hormones and the occurrence of AAA in elderly men.

METHODS

A prospective case-control study was conducted including 452, 65-year old men participating in screening for AAA, 2013-2019; 230 men with AAA and 222 men with an aortic diameter<30mm (controls). Questionnaires and blood samples were collected and stored consecutively. Serum levels of total testosterone, estradiol, progesterone, luteinizing hormone and sex hormone binding globulin were analyzed by electrochemiluminescent immunoassays. Multivariable logistic regression analysis was used to assess the association of sex hormones with AAA.

RESULTS

The median aneurysm diameter was 33mm. Men with AAA had higher estradiol and progesterone levels than controls (93pmol/L vs. 84pmol/L, p=.003 and 0.41nmol/L vs. 0.17nmol/L, p<.001). Testosterone levels were lower in men with AAA than in controls (13nmol/L vs. 14nmol/L, p=.026). AAA was associated with detectable levels of progesterone(OR 6.69, 95%CI 3.86-11.47), smoking(OR 5.26, 95%CI 3.12-8.85), coronary heart disease(OR 4.06, 95%CI 1.92-8.58) and body mass index>25(OR 2.26, 95%CI 1.34-3.82).

CONCLUSION

The observed higher levels of estradiol and progesterone in men with AAA, suggest an impact of sex hormones on aneurysm development. The association between progesterone levels and aortic diameter, stress the importance of focusing on the potential effect of this unconsidered female sex hormone on aneurysm formation.

Autoantibodies associated with primary biliary cholangitis are common among patients with systemic lupus erythematosus even in the absence of elevated liver enzymes

Knowledge of concomitant autoimmune liver diseases (AILD) is more detailed in primary Sjögren's syndrome (pSS) compared to systemic lupus erythematosus (SLE). Herein, the prevalence of autoantibodies associated with autoimmune hepatitis (AIH) and primary biliary cholangitis (PBC) was investigated in stored sera from patients with SLE (n = 280) and pSS (n = 114). Antibodies against mitochondria (AMA), liver-kidney microsomal (LKM) antigen, smooth muscle (SMA) and anti-nuclear antibodies (ANA) were analysed with immunofluorescence microscopy. In addition, AILD-associated autoantibodies were tested with immunoblot. Prior to sampling, eight SLE (2·9%) and three pSS (2·6%) cases were diagnosed with AILD. Among SLE-cases without known AILD (n = 272), 26 (9·6%) had PBC-associated autoantibodies, 15 (5·5%) AIH-associated autoantibodies (excluding ANA) and one serological overlap. Most subjects with PBC-associated autoantibodies had liver enzymes within reference limits (22 of 27, 81%) or mild laboratory cholestasis (two of 27, 7·4%), while one fulfilled the diagnostic PBC-criteria. AMA-M2 detected by immunoblot was the most common PBC-associated autoantibody in SLE (20 of 272, 7·4%). The prevalence of SMA (4·4%) was comparable with a healthy reference population, but associated with elevated liver enzymes in four of 12 (25%), none meeting AIH-criteria. The patient with combined AIH/PBC-serology had liver enzymes within reference limits. Among pSS cases without known AILD (n = 111), nine (8·1%) had PBC-associated, 12 (10·8%) AIH-associated autoantibodies and two overlapped. PBC-associated autoantibodies were found as frequently in SLE as in pSS but were, with few exceptions, not associated with laboratory signs of liver disease. Overall, AILD-associated autoantibodies were predominantly detected by immunoblot and no significant difference in liver enzymes was found between AILD autoantibody-negative and -positive patients.

Risk of myocardial infarction in middle aged and older patients with coarctation of the aorta

Introduction

Previous case-control studies have compared the risk of coronary artery disease/myocardial infarction (MI) in patients with coarctation of the aorta (CoA) with other congenital heart disease diagnoses, however, these studies have only included younger patients in their 20s and 30s, not older patients. As the atherosclerotic burden is increasing with increasing age, it is important to study the risk of MI in older patients (from early middle age and older) with CoA.

Purpose

The aim of our study was to investigate the risk of MI in older patients (≥40 years) with CoA, and to compare this risk with the risk in patients of the same age with ventricular septal defects (VSD), the most common congenital heart condition.

Methods

We used data from the Swedish National Patient Registry (NPR) to identify all patients alive at 40 years of age with a diagnosis of CoA or VSD, born during the period 1930–1970. The follow-up through the NPR and the Cause-specific Death Registry started in January 1970 and went on until December 2017.

Results

Altogether 1204 patients with CoA and 2079 patients with VSD were identified in the registers, and in total, 97 (8.1%) patients with CoA and 162 (7.8%) patients with VSD developed an MI during follow up. Mean follow up time was 20.6±10.3 years in CoA patients and 21.3±10.9 in the VSD group. The risk of MI was similar in CoA compared with VSD patients (HR 1.1, 95% confidence interval 0.9–1.5, p=0.3) Median age at MI was similar in CoA patients and in VSD patients; in CoA 59.8 years (range 40.1–87.5), in VSD 61.2 (range 40.2–87.5), p=0.3. Hypertension (diagnosed before MI or within a year after MI) was more common in CoA patients with an MI (58.8%) compared with VSD patients (37.7%), however, prevalence of diabetes mellitus and hyperlipidemia was similar in both patient groups (18.6% and 21.6% in CoA respectively, compared to 17.9% and 22.8% in VSD group). After adjustment for hypertension, diabetes mellitus and hyperlipidemia, the risk of MI remained similar in patients with CoA and VSD (hazard ratio 1.1, 95% confidence interval 0.8–1.4, p=0.5).

Conclusion

In this large nationwide study, we found that in older patients with CoA (median age at MI 60 years, range 40–88 years) the risk of MI was not increased and similar to that of patients with VSD with similar age at MI. Adjustment for hypertension, diabetes mellitus and hyperlipidemia did not modify this finding which suggests that patients with CoA do not have an increased risk of MI, compared to patients with VSD.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was funded by the Swedish state under an agreement between the Swedish government and county councils, the ALF agreement (Grant number: 236611) and the Swedish Heart-Lung Foundation (Grant Number: 20090724).

Transcatheter interventions of coarctation of the aorta (CoA): a multinational population-based registry – procedural complications

Background

Patients with a native or re CoA with an invasively meassured peak to peak gardient &gt;20 mmHg have a guideline indication for intervention. The decision regarding transcatheter versus surgical intervention depends on a variety of factors including location and complexity of CoA, patient/parent preference and availability of a team capable to perform the intevention with a low rate of complications. The aim of the present analysis was to describe factors associated with risk for procedural complications during transcatheter interventions in CoA. Separate anlysis was done for complications at intervention site and at access site.

Methods

All consecutive patients undergoing catheter interventions for CoA from 1st of January 2000 to 31st of December 2016 were identified by each of the particpating nine centers. The nine centers perform all catheter interventions for CoA for a complete population coverage of 25 millions inhabitants. A common protocol was filled out from medical records. Exclusion criteria were weight less than 20 kg at the time of intervention or Norwood surgery for hypoplastic left heart surgery. Complications at the intervention site included aneurysm formation, dissection of the aorta, extravasation of the aorta or neurological impairment. Complications at the access site was defined as any complication that prolonged the hospital stay.

Results

590 interventions were performed on 520 patients: two interventions n=76, three: n=11, four n=2 and one patient underwent five interventions. There was no mortality in relation to the procedure or during the hospitalisation. The age span of the patients was wide; 4–79 years old (median= 23). 51% had a native CoA, 42% post surgery re-CoA, 22% had had a previous catheter intervention. In 160 (27%) of the interventions balloon dilatation only was performed. Overall, procedural succes was 87%, n=513, 44 procedures (8%) were partially successful and 9 procedures (2%) were not successful. 512 (87%) had one day in hospital stay and 17 patients (6%) had a hospital stay longer than 3 days. In 11 procedures (1.9%) at least one complication occurred at the intervention site; (6 aneurysm formation, 3 neurological impairment, 3 dissection of aorta, 2 extra vasation of aorta), nine of them without prolonged hospital stay. In 25 procedures (4.2%) at least one complications at the access site was observed. Access site complications were associated with older age (mean 38 years (10–79))

Conclusions

In a large, multicenter registry with complete follow-up, complications at the intervention site occurred in 1.9% and at the access site in 4.2% of interventions. Transcatheter intervention of CoA can be performed with low risk of complications.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): ALF-LUA, Gothenburg Heart and Lung Foundation

Risk of ischemic stroke in adult patients with congenital heart disease

Introduction

With an increasing proportion of adults with congenital heart disease (CHD) surviving into middle age and beyond, CHD patients will be at increased risk of acquired cardiovascular conditions, such as ischemic stroke. Compared to controls, patients with CHD have a higher prevalence of arrhythmias, persistent shunts enabling paradoxical embolization, heart failure, mechanical valves as well as potentially hypercoagulable states, all of which can further increase the risk of stroke.

Purpose

The aim of our study was to investigate the risk of developing ischemic stroke in adults with CHD in Sweden compared to controls from the general population.

Methods

We used data from the Swedish National Patient and Cause of Death registries to identify all CHD patients ≥18 years of age, born during the period 1930–1998, with a first time diagnosis of ischemic stroke. Follow-up started in January 1970 and went on until December 2017. Approximately ten controls matched for age and sex were randomly selected from the general population for each patient with CHD. CHD diagnoses were classified into six lesion groups according to a previously published hierarchical classification system.

Results

In total, 43,110 patients with CHD and 474,267 controls were included in the study (51.4% men) and mean follow up time was 25.4±18.4 years. Patients with CHD had a 6 times higher risk of developing an ischemic stroke compared with controls (hazard ratio 6.0, 95% confidence interval 5.8–6.2, p≤0.001), with altogether 8.8% (n=3785) of CHD patients developing ischemic stroke compared with 1.6% (n=7516) of controls. Ischemic stroke was more common in all CHD lesion groups; however, patients with atrial septal defects/patent foramen ovale had the highest incidence rate of ischemic stroke with an incidence rate of 76.1 events/10,000 patient years compared with 8.7 in controls. Patients with CHD and ischemic stroke had markedly less hypertension, diabetes mellitus and hypercholesterolemia, compared with controls (7.1%, 2.0%, 2.9% respectively in CHD patients, compared with 19.6%, 6.6%, 5.3%, in controls, p≤0.001 for all). In addition, atrial fibrillation and heart failure were only slightly more common in CHD patients with ischemic stroke compared to controls (atrial fibrillation: 12.0% in CHD vs 10.4% in controls, p=0.01; heart failure: 8.7% in CHD vs 7.3% in controls, p=0.009).

Conclusion

In this large nationwide study, we found that the risk of ischemic stroke in adult patients with CHD was six times higher than in controls, despite a lower prevalence of common risk factors for stroke such as hypertension, diabetes mellitus and hypercholesterolemia. In addition, atrial fibrillation and heart failure were only slightly more common in CHD patients compared with controls. This implies that the etiology of ischemic stroke might be different in CHD patients compared with controls.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was funded by the Swedish state under an agreement between the Swedish government and county councils, the ALF agreement (Grant number: 236611) and the Swedish Heart-Lung Foundation (Grant Number: 20090724).

Transcatheter intervention of coarctation of the aorta (CoA): a multinational population-based registry – effect on hypertension

Background

CoA is associated with hypertension caused by reduced wind kessel function in the aortic arch, general hypoplasia of the arch and/or essential hypertension. In patients with a native or recurrent/rest CoA, a gradient &gt;20 mmHg by non-invasive meassurement if associated with hypertension is an ESCguideline indication for intervention. We studied the persistence and presence of hypertension after transcatheter intervention of a CoA

Methods

All consecutive patients undergoing catheter interventions for CoA from 1st of January 2000 to 31st of December 2016 were identified by each of the particpating nine centers. The nine centers perform all catheter interventions for CoA for a complete population coverage of 25 millions inhabitants. A common protocoll was filled out from medical records. Hypertension was defined as a pre-intervention blood pressure above 140/80 or pharmacological treatment of hypertension. Exclusion criteria were weight less than 20 kg at the time of intervention or Norwood surgery

Results

590 interventions were performed on 520 patients: two interventions n=76, three: n=11, four n=2 and one patient underwent five interventions. Before intervention, 437 (74%) of the patients were hypertensive and 285 were on pharmacologocal treatment; 134 (48%) were treated with one drug, 79 patients (28%) with two drugs, 41 patients (15%) with three drugs and 14 (5%) with four drugs. After the intervention during follow up hypertension was present in 294 patients (50%, p&lt;0.001 vs pre) of whom 270 (46%) were on pharmacological treatment; with one drug, n=128 (48%), two drugs n=93 (34%), three drugs n=34 (13%) or 4 drugs n=7 (3%).

Conclusions

Catheter intervention of CoA reduced the presence of hypertension significantly from 74% down to 50% but many patients will remain hypertensive and in need for treatment. Life time follow up also after transcatheter CoA intervention seems warranted.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): ALF-LUA, Heart and Lung Foundation

New candidate genes for ST-elevation myocardial infarction

BACKGROUND

Despite extensive research in atherosclerosis, the mechanisms of coronary atherothrombosis in ST-elevation myocardial infarction (STEMI) patients are undetermined.

OBJECTIVES

Our aim was to find candidate genes involved in STEMI by analysing leucocyte gene expression in STEMI patients, without the influence of secondary inflammation from innate immunity, which was assumed to be a consequence rather than the cause of coronary atherothrombosis.

METHODS

Fifty-one patients were included at coronary angiography because of STEMI. Arterial blood was sampled in the acute phase (P1), at 24-48 h (P2) and at 3 months (P3). Leucocyte RNA was isolated and gene expression analysis was performed by Affymetrix Human Transcriptome Array 2.0. By omission of up- or downregulated genes at P2, secondary changes from innate immunity were excluded. Genes differentially expressed in P1 when compared to the convalescent sample in P3 were determined as genes involved in STEMI.

RESULTS

Three genes were upregulated at P1 compared to P3; ABCG1 (P = 5.81 × 10^-5 ), RAB20 (P = 3.69 × 10^-5 ) and TMEM2 (P = 7.75 × 10^-6 ) whilst four were downregulated; ACVR1 (P = 9.01 × 10^-5 ), NFATC2IP (P = 8.86 × 10^-5 ), SUN1 (P = 3.87 × 10^-5 ) and TTC9C (P = 7.18 × 10^-6 ). These genes were also highly expressed in carotid atherosclerotic plaques.

CONCLUSIONS

We found seven genes involved in STEMI. The study is unique regarding the blood sampling in the acute phase and omission of secondary expressed genes from innate immunity. However, the results need to be replicated by future studies.

Subclinical atherosclerosis and its progression are modulated by PLIN2 through a feed-forward loop between LXR and autophagy

BACKGROUND

Hyperlipidaemia is a major risk factor for cardiovascular disease, and atherosclerosis is the underlying cause of both myocardial infarction and stroke. We have previously shown that the Pro251 variant of perilipin-2 reduces plasma triglycerides and may therefore be beneficial to reduce atherosclerosis development.

OBJECTIVE

We sought to delineate putative beneficial effects of the Pro251 variant of perlipin-2 on subclinical atherosclerosis and the mechanism by which it acts.

METHODS

A pan-European cohort of high-risk individuals where carotid intima-media thickness has been assessed was adopted. Human primary monocyte-derived macrophages were prepared from whole blood from individuals recruited by perilipin-2 genotype or from buffy coats from the Karolinska University hospital blood central.

RESULTS

The Pro251 variant of perilipin-2 is associated with decreased intima-media thickness at baseline and over 30 months of follow-up. Using human primary monocyte-derived macrophages from carriers of the beneficial Pro251 variant, we show that this variant increases autophagy activity, cholesterol efflux and a controlled inflammatory response. Through extensive mechanistic studies, we demonstrate that increase in autophagy activity is accompanied with an increase in liver-X-receptor (LXR) activity and that LXR and autophagy reciprocally activate each other in a feed-forward loop, regulated by CYP27A1 and 27OH-cholesterol.

CONCLUSIONS

For the first time, we show that perilipin-2 affects susceptibility to human atherosclerosis through activation of autophagy and stimulation of cholesterol efflux. We demonstrate that perilipin-2 modulates levels of the LXR ligand 27OH-cholesterol and initiates a feed-forward loop where LXR and autophagy reciprocally activate each other; the mechanism by which perilipin-2 exerts its beneficial effects on subclinical atherosclerosis.

P1217Zirconium-89 labelled probe for molecular imaging of inflammation in experimental atherosclerosis

Background

Early detection of inflamed atherosclerotic lesions by molecular imaging might improve risk assessment beyond that of vascular stenosis and plaque morphology imaging, and improve the clinical management of high-risk patients.

Purpose

To target the key features of unstable atherosclerotic lesions, we studied the feasibility of our radiotracer, based on modified human serum albumin (HSA), to identify inflamed atherosclerotic lesions by in vivo molecular imaging.

Methods

We applied a maleylated HSA (Mal-HSA) probe, recognised by scavenger receptors on macrophages, in an experimental in vivo imaging study of atherosclerosis. Mal-HSA was coupled with a positron-emittingmetal ion, Zirconium-89 (89Zr). The targeting potential of this probe was evaluated and compared with unspecific 89Zr-HSA and 18F-FDG in a mouse model of atherosclerosis (Apoe−/−, n=22) and compared with wild-type (WT) mice (C57BL/6, n=21) as controls. Radiotracer accumulation in the aortic arch was analysed in vivo by the fusion of positron emission tomography–magnetic resonance imaging (PET-MRI), radiotracer bio-distribution was measured ex vivo by gamma counter, and plaque uptake was evaluated by phosphor imaging (PI) autoradiography (ARG).

Results

PET-MRI, gamma counter measurements, and PI-ARG showed the accumulation of 89Zr-Mal-HSA in the atherosclerotic lesions of Apoe−/− mice. The maximum standardised uptake value (SUVmax) for 89Zr-Mal-HSA at 16 and 20 weeks were 26% and 20% higher (P<0.05) in Apoe−/− mice than control WT mice, whereas no difference in SUVmax was found for 18F-FDG in the same animals. 89Zr-Mal-HSA uptake in the aorta as evaluated by gamma counter 48 h post-injection was 32% higher (P<0.01) for Apoe−/− mice compared to WT mice, and the aorta-to-blood ratio was 10-fold higher (P<0.001) for 89Zr-Mal-HSA compared with unspecific 89Zr-HSA. HSA probes were mainly distributed to the liver, spleen, kidneys, bone and lymph nodes. The PI-ARG results corroborated the PET and gamma counter measurements, showing higher accumulation of 89Zr-Mal-HSA in the aortas of Apoe−/− mice compared to WT mice; 9.4±1.4 vs 0.8±0.3% (P<0.001).

Conclusions

The modified HSA-based radiotracer showed in vivo targeting of inflamed atherosclerotic lesions of mouse aorta, which could also be verified ex vivo. 89Zr-Mal-HSA seems to be a promising diagnostic tool for the identification of vascular inflammation. Further methodological studies are needed to verify its applicability for detecting rupture-prone plaques.

Acknowledgement/Funding

Swedish Research Council (22036); the Swedish HLF (20150423, 20170669); ALF (20150517, 447561, 726481); Söderberg Foundations, VINNOVA and KI

Concomitant Ro/SSA and La/SSB antibodies are biomarkers for the risk of venous thromboembolism and cerebral infarction in primary Sjögren's syndrome

BACKGROUND

To assess the risk of incident cardiovascular disease in patients with primary Sjögren's syndrome, overall and stratified by Ro/SSA and La/SSB autoantibody status.

METHODS

A cohort of patients with primary Sjögren's syndrome in Sweden (n = 960) and matched controls from the general population (n = 9035) were included, and data extracted from the National Patient Register to identify events of myocardial infarction, cerebral infarction and venous thromboembolism. Hazard ratios were estimated using cox proportional hazard regressions.

RESULTS

During a median follow-up of 9.5 years, the overall hazard ratio (HR) was 1.6 (95% CI 1.2-2.1) for myocardial infarction, 1.2 (95% CI 0.9-1.7) for cerebral infarction and 2.1 (95% CI 1.6-2.9) for venous thromboembolism. Patients positive for both Ro/SSA and La/SSB autoantibodies had a substantially higher risk of cerebral infarction (HR 1.7, 95% CI 1.0-2.9) and venous thromboembolism (HR 3.1, 95% CI 1.9-4.8) than the general population. These risks were not significantly increased in Ro/SSA- and La/SSB-negative patients. Among autoantibody-positive patients, the highest HR of cerebral infarction was seen after ≥10 years disease duration (HR 2.8, 95% CI 1.4-5.4), while the HR for venous thromboembolism was highest 0-5 years after disease diagnosis (HR 4.7, 95% CI 2.3-9.3) and remained high throughout disease duration.

CONCLUSIONS

Primary Sjögren's syndrome is associated with a markedly increased risk of cardiovascular disease and the presence of Ro/SSA and La/SSB autoantibodies identify the subgroup of patients carrying the highest risk. These findings suggest that monitoring and prevention of cardiovascular disease in this patient group should be considered.

P6599Upregulation of protein and gene expression of arginase-1 in patients with ST elevation myocardial infarction

Background

The mechanisms underlying rupture of a coronary atherosclerotic plaque and development of myocardial ischemia-reperfusion injury in ST-elevation myocardial infarction (STEMI) remain unknown. Increased arginase-1 activity leads to reduced nitric oxide production and increased formation of reactive oxygen species due to uncoupling of the endothelial nitric oxide synthase (eNOS). These events lead to endothelial dysfunction, plaque instability and increased susceptibility to ischemia-reperfusion injury in acute myocardial infarction. Experimental studies have shown that arginase-1 expression and activity are increased in atherosclerosis and during myocardial ischemia-reperfusion. Accordingly, inhibition of arginase-1 reduces atherosclerotic lesion development and limits the extent of infarct size during ischemia-reperfusion via an eNOS-dependent mechanism. Furthermore, arginase-1 inhibition improves endothelial function in patients with coronary artery disease but the potential role of arginase-1 in patients with STEMI is poorly understood.

Purpose

The purpose of the current study was to test the hypothesis that arginase-1 is upregulated and correlate to infarct size in STEMI patients.

Methods and results

Two independent cohorts of STEMI patients were included. In cohort 1, plasma and buffy coat leukocytes were collected from 53 STEMI patients at the time of arterial puncture for percutaneous coronary intervention, at 24–48 hours post STEMI and at 3 months post STEMI. Gene expression in leukocytes was determined in 51 patients with Affymetrix Human Transcriptome Array 2.0. In cohort 2, plasma was collected from 82 STEMI patients at admission and at 6 months for determination of plasma arginase-1. These patients underwent cardiac magnetic resonance imaging performed at day 4–7 and at 6 months post STEMI. Plasma arginase-1 levels were quantified with ELISA. Control blood samples were collected from 56 healthy age matched subjects. In cohort 1, ARG1 gene expression was four-fold higher in STEMI patients at admission compared to controls (Figure A). This expression returned to control levels within 3 months. Plasma arginase-1 levels were two times higher in STEMI patients at admission compared to controls, and remained elevated at 24–48 hours and at 3 months post STEMI (Figure B). The increase in plasma arginase-1 in STEMI patients was confirmed in cohort 2 (Figure C). Arginase-1 levels did not correlate with infarct size.

Conclusions

STEMI patients demonstrate increased gene expression and plasma levels of arginase-1 in the acute setting. In contrast to gene expression plasma arginase-1 levels remain significantly elevated over time. The markedly increased expression of arginase-1 already at admission may suggest a mechanistic role of arginase-1 in the development of STEMI. Further studies are needed to elucidate whether increased expression, induction and activity of arginase-1 are contributing factors for the development of STEMI.

P728Subclinical atherosclerosis and its progression are modulated by perilipin-2 through a feed-forward loop between LXR and autophagy

Background

Hyperlipidemia is a major risk factor for cardiovascular disease and atherosclerosis is the underlying cause of both myocardial infarction and stroke. We have previously shown that the Pro251 variant of perilipin-2 reduces plasma triglycerides and may therefore be beneficial for atherosclerosis development.

Purpose

We sought to delineate putative beneficial effects of the Pro251 variant of perlipin-2 on subclinical atherosclerosis and the mechanism by which it acts.

Methods

A pan-European cohort of high-risk individuals where carotid intima-media thickness has been assessed was adopted. Human primary monocyte-derived macrophages were prepared from whole blood from individuals recruited by perilipin-2 genotype, or from buffy coats from the our University hospital blood central.

Results

The Pro251 variant of perilipin-2 is associated with decreased intima-media thickness at baseline and 30 months follow-up. Using human primary monocyte-derived macrophages from carriers of the beneficial Pro251 variant we show that this variant increases autophagy activity, cholesterol efflux, and a controlled inflammatory response. Through extensive mechanistic studies we demonstrate that increase in autophagy activity is accompanied with an increase in LXR activity and that LXR and autophagy reciprocally activate each other in a feed-forward loop, regulated by CYP27A1 and 27OH-cholesterol.

Conclusions

For the first time, we show that perilipin-2 affects susceptibility to human atherosclerosis through activation of autophagy and stimulation of cholesterol efflux. We demonstrate that perilipin-2 modulates levels of the LXR ligand 27OH-cholesterol and initiates a feed-forward loop where LXR and autophagy reciprocally activate each other; the mechanism by which perilipin-2 exerts its beneficial effects on subclinical atherosclerosis.

Acknowledgement/Funding

The Swedish Research Council, Swedish Heart-Lung Foundation, Marianne and Marcus Wallenberg's Foundation, Swedish Medical Society

Infections increase the risk of developing Sjögren's syndrome

OBJECTIVE

Environmental factors have been suggested in the pathogenesis of rheumatic diseases. We here investigated whether infections increase the risk of developing primary Sjögren's syndrome (pSS).

METHODS

Patients with pSS in Sweden (n = 945) and matched controls from the general population (n = 9048) were included, and data extracted from the National Patient Register to identify infections occurring before pSS diagnosis during a mean observational time of 16.0 years. Data were analysed using conditional logistic regression models. Sensitivity analyses were performed by varying exposure definition and adjusting for previous health care consumption.

RESULTS

A history of infection associated with an increased risk of pSS (OR 1.9, 95% CI 1.6-2.3). Infections were more prominently associated with the development of SSA/SSB autoantibody-positive pSS (OR 2.7, 95% CI 2.0-3.5). When stratifying the analysis by organ system infected, respiratory infections increased the risk of developing pSS, both in patients with (OR 2.9, 95% CI 1.8-4.7) and without autoantibodies (OR 2.1, 95% CI 1.1-3.8), whilst skin and urogenital infections only significantly associated with the development of autoantibody-positive pSS (OR 3.2, 95% CI 1.8-5.5 and OR 2.7, 95% CI 1.7-4.2). Furthermore, a dose-response relationship was observed for infections and a risk to develop pSS with Ro/SSA and La/SSB antibodies. Gastrointestinal infections were not significantly associated with a risk of pSS.

CONCLUSIONS

Infections increase the risk of developing pSS, most prominently SSA/SSB autoantibody-positive disease, suggesting that microbial triggers of immunity may partake in the pathogenetic process of pSS.

HDAC inhibition in glioblastoma monitored by hyperpolarized 13 C MRSI

Vorinostat is a histone deacetylase (HDAC) inhibitor that inhibits cell proliferation and induces apoptosis in solid tumors, and is in clinical trials for the treatment of glioblastoma (GBM). The goal of this study was to assess whether hyperpolarized ¹³ C MRS and magnetic resonance spectroscopic imaging (MRSI) can detect HDAC inhibition in GBM models. First, we confirmed HDAC inhibition in U87 GBM cells and evaluated real-time dynamic metabolic changes using a bioreactor system with live vorinostat-treated or control cells. We found a significant 40% decrease in the ¹³ C MRS-detectable ratio of hyperpolarized [1-¹³ C]lactate to hyperpolarized [1-¹³ C]pyruvate, [1-¹³ C]Lac/Pyr, and a 37% decrease in the pseudo-rate constant, k_PL , for hyperpolarized [1-¹³ C]lactate production, in vorinostat-treated cells compared with controls. To understand the underlying mechanism for this finding, we assessed the expression and activity of lactate dehydrogenase (LDH) (which catalyzes the pyruvate to lactate conversion), its associated cofactor nicotinamide adenine dinucleotide, the expression of monocarboxylate transporters (MCTs) MCT1 and MCT4 (which shuttle pyruvate and lactate in and out of the cell) and intracellular lactate levels. We found that the most likely explanation for our finding that hyperpolarized lactate is reduced in treated cells is a 30% reduction in intracellular lactate levels that occurs as a result of increased expression of both MCT1 and MCT4 in vorinostat-treated cells. In vivo ¹³ C MRSI studies of orthotopic tumors in mice also showed a significant 52% decrease in hyperpolarized [1-¹³ C]Lac/Pyr when comparing vorinostat-treated U87 GBM tumors with controls, and, as in the cell studies, this metabolic finding was associated with increased MCT1 and MCT4 expression in HDAC-inhibited tumors. Thus, the ¹³ C MRSI-detectable decrease in hyperpolarized [1-¹³ C]lactate production could serve as a biomarker of response to HDAC inhibitors.

The mir-200 family regulates key pathogenic events in ascending aortas of individuals with bicuspid aortic valves

BACKGROUND

An individual with a bicuspid aortic valve (BAV) runs a substantially higher risk of developing aneurysm in the ascending aorta compared to the normal population with tricuspid aortic valves (TAV). Aneurysm formation in patients with BAV and TAV is known to be distinct at the molecular level but the underlying mechanisms are undefined. Here, we investigated the still incompletely described role of microRNAs (miRNAs), important post-transcriptional regulators of gene expression, in such aortic disease of patients with BAV as compared with TAV.

METHODS AND RESULTS

Using a system biology approach, based on data obtained from proteomic analysis of non-dilated aortas from BAV and TAV patients, we constructed a gene-interaction network of regulatory microRNAs associated with the observed differential protein signature. The miR-200 family was the highest ranked miRNA, hence potentially having the strongest effect on the signalling network associated with BAV. Further, qRT-PCR and ChIP analyses showed lower expression of miR-200c, higher expression of miR-200 target genes, ZEB1/ZEB2 transcription factors, and higher chromatin occupancy of the miR-200c promoter by ZEB1/ZEB2 in BAV patients, indicating a miR-200c/ZEBs negative feedback loop and induction of endothelial/epithelial mesenchymal transition (EndMT/EMT).

CONCLUSION

We propose that a miR-200-dependent process of EndMT/EMT is a plausible biological mechanism rendering the BAV ascending aorta more prone to aneurysm development. Although initially supported by a miR-200c/ZEB feedback loop, this process is most probably advanced by cooperation of other miRNAs.

Integrative studies implicate matrix metalloproteinase-12 as a culprit gene for large-artery atherosclerotic stroke

BACKGROUND

Ischaemic stroke and coronary heart disease are important contributors to the global disease burden and share atherosclerosis as the main underlying cause. Recent evidence from a genome-wide association study (GWAS) suggested that single nucleotide polymorphisms (SNP) near the MMP12 gene at chromosome 11q22.3 were associated with large-vessel ischaemic stroke. Here, we evaluated and extended these results by examining the relationship between MMP12 and atherosclerosis in clinical and experimental studies.

METHODS AND RESULTS

Plasma concentrations of MMP12 were measured at baseline in 3394 subjects with high-risk for cardiovascular disease (CVD) using the Olink ProSeek CVD I array. The plasma MMP12 concentration showed association with incident cardiovascular and cerebrovascular events (130 and 67 events, respectively, over 36 months) and carotid intima-media thickness progression (P = 3.6 × 10^-5 ). A GWAS of plasma MMP12 concentrations revealed that SNPs rs499459, rs613084 and rs1892971 at chr11q22.3 were independently associated with plasma MMP12 (P < 5 × 10^-8 ). The lead SNPs showed associations with mRNA levels of MMP12 and adjacent MMPs in atherosclerotic plaques. MMP12 transcriptomic and proteomic levels were strongly significantly increased in carotid plaques compared with control arterial tissue and in plaques from symptomatic versus asymptomatic patients. By combining immunohistochemistry and proximity ligation assay, we demonstrated that MMP12 localizes to CD68 + macrophages and interacts with elastin in plaques. MMP12 silencing in human THP-1-derived macrophages resulted in reduced macrophage migration.

CONCLUSIONS

Our study supports the notion that MMP12 is implicated in large-artery atherosclerotic stroke, functionally by enhancing elastin degradation and macrophage invasion in plaques.

Successful treatment of refractory systemic lupus erythematosus using proteasome inhibitor bortezomib followed by belimumab: description of two cases

Although the putative therapeutic options for patients with systemic lupus erythematosus (SLE) are steadily increasing, refractory disease is indeed a major challenge to many clinicians and patients. The proteasome inhibitor bortezomib – approved for the treatment of multiple myeloma since the beginning of this century – was recently reported successful in twelve cases of refractory SLE by German colleagues. Herein, we describe two Swedish SLE cases with refractory renal and pulmonary manifestations that were rescued by bortezomib as induction of remission followed by monthly doses of belimumab. The patients were carefully monitored with regard to disease activity and renal function. Anti-dsDNA and anti-C1q antibodies, complement proteins and lymphocyte subsets were analysed in consecutive samples. In December 2016, the patients had been in clinical remission post bortezomib administration for a period of 28 and 22 months, respectively. Potential benefits of using belimumab as maintenance therapy to prevent regeneration of autoreactive B cell clones are discussed.

GLUT3 upregulation promotes metabolic reprogramming associated with antiangiogenic therapy resistance

Clinical trials revealed limited response duration of glioblastomas to VEGF-neutralizing antibody bevacizumab. Thriving in the devascularized microenvironment occurring after antiangiogenic therapy requires tumor cell adaptation to decreased glucose, with 50% less glucose identified in bevacizumab-treated xenografts. Compared with bevacizumab-responsive xenograft cells, resistant cells exhibited increased glucose uptake, glycolysis, ¹³C NMR pyruvate to lactate conversion, and survival in low glucose. Glucose transporter 3 (GLUT3) was upregulated in bevacizumab-resistant versus sensitive xenografts and patient specimens in a HIF-1α-dependent manner. Resistant versus sensitive cell mitochondria in oxidative phosphorylation-selective conditions produced less ATP. Despite unchanged mitochondrial numbers, normoxic resistant cells had lower mitochondrial membrane potential than sensitive cells, confirming poorer mitochondrial health, but avoided the mitochondrial dysfunction of hypoxic sensitive cells. Thin-layer chromatography revealed increased triglycerides in bevacizumab-resistant versus sensitive xenografts, a change driven by mitochondrial stress. A glycogen synthase kinase-3β inhibitor suppressing GLUT3 transcription caused greater cell death in bevacizumab-resistant than -responsive cells. Overexpressing GLUT3 in tumor cells recapitulated bevacizumab-resistant cell features: survival and proliferation in low glucose, increased glycolysis, impaired oxidative phosphorylation, and rapid in vivo proliferation only slowed by bevacizumab to that of untreated bevacizumab-responsive tumors. Targeting GLUT3 or the increased glycolysis reliance in resistant tumors could unlock the potential of antiangiogenic treatments.