Oncological and functional outcomes for transoral robotic surgery following previous radiation treatment for upper aerodigestive tract head and neck cancers. A French multicenter GETTEC group study

BACKGROUND

Transoral robotic surgery (TORS) opens new perspectives. We evaluated the outcomes for patients having undergone TORS after previous radiotherapy.

METHODS

A retrospective multicenter study (n = 138) in a previously irradiated area between 2009 and 2020. Survival was assessed with the Kaplan-Meier method. Prognostic factors were evaluated using a chi-squared test, Fisher's test, or Wilcoxon's test.

RESULTS

The median length of hospital stay was 12.5 days. Bleeding was the most frequent postoperative complication (15.2%, n = 22). Prophylactic vessel ligation did not significantly decrease bleeding. Complications were significantly lower for Tis, T1, and N0 tumors. 91.6% (n = 120) of the patients with a perioperative tracheotomy could be decannulated. Larynx was functional for 65.94% of the patients. The median length of follow-up was 26 months. The 5-year overall and relapse-free survival rates were respectively 59.9% and 43.4%.

CONCLUSION

Oncological and functional results confirmed the value of TORS as a treatment in previously irradiated area.

Peripheral blood immune cell profiling of acute corneal transplant rejection

Acute rejection (AR) of corneal transplants (CT) has a profound effect on subsequent graft survival but detailed immunological studies in human CT recipients are lacking. In this multi-site, cross-sectional study, clinical details and blood samples were collected from adults with clinically diagnosed AR of full-thickness (FT)-CT (n = 35) and posterior lamellar (PL)-CT (n = 21) along with Stable CT recipients (n = 177) and adults with non-transplanted corneal disease (n = 40). For those with AR, additional samples were collected 3 months later. Immune cell analysis was performed by whole-genome microarrays (whole blood) and high-dimensional multi-color flow cytometry (peripheral blood mononuclear cells). For both, no activation signature was identified within the B cell and T cell repertoire at the time of AR diagnosis. Nonetheless, in FT- but not PL-CT recipients, AR was associated with differences in B cell maturity and regulatory CD4⁺ T cell frequency compared to stable allografts. These data suggest that circulating B cell and T cell subpopulations may provide insights into the regulation of anti-donor immune response in human CT recipients with differing AR risk. Our results suggest that, in contrast to solid organ transplants, genetic or cellular assays of peripheral blood are unlikely to be clinically exploitable for prediction or diagnosis of AR.

Intracranial Aneurysm Classifier Using Phenotypic Factors: An International Pooled Analysis

Intracranial aneurysms (IAs) are usually asymptomatic with a low risk of rupture, but consequences of aneurysmal subarachnoid hemorrhage (aSAH) are severe. Identifying IAs at risk of rupture has important clinical and socio-economic consequences. The goal of this study was to assess the effect of patient and IA characteristics on the likelihood of IA being diagnosed incidentally versus ruptured. Patients were recruited at 21 international centers. Seven phenotypic patient characteristics and three IA characteristics were recorded. The analyzed cohort included 7992 patients. Multivariate analysis demonstrated that: (1) IA location is the strongest factor associated with IA rupture status at diagnosis; (2) Risk factor awareness (hypertension, smoking) increases the likelihood of being diagnosed with unruptured IA; (3) Patients with ruptured IAs in high-risk locations tend to be older, and their IAs are smaller; (4) Smokers with ruptured IAs tend to be younger, and their IAs are larger; (5) Female patients with ruptured IAs tend to be older, and their IAs are smaller; (6) IA size and age at rupture correlate. The assessment of associations regarding patient and IA characteristics with IA rupture allows us to refine IA disease models and provide data to develop risk instruments for clinicians to support personalized decision-making.

Burden of rare variants in arrhythmogenic cardiomyopathy with right dominant form associated genes provides new insights for molecular diagnosis and clinical management

Arrhythmogenic cardiomyopathy with right dominant form (ACR) is a rare heritable cardiac cardiomyopathy disorder associated with sudden cardiac death. Pathogenic variants in desmosomal genes have been causally related to ACR in 40% of cases. Other genes encoding non desmosomal proteins have been described in ACR but their contribution in this pathology is still debated. A panel of 71 genes associated with inherited cardiopathies was screened in an ACR population of 172 probands and 856 individuals from the general population. Pathogenic variants (PV) and variants of uncertain significance (VUS) have been identified in 36% and 18.6% of patients respectively. Among the cardiopathy associated genes, burden tests show a significant enrichment in PV and VUS only for desmosomal genes PKP2, DSP, DSC2 and DSG2. Importantly, VUS may account for 15% of ACR cases and should then be considered for molecular diagnosis. Among the other genes, no evidence of enrichment was detected, suggesting an extreme caution in the interpretation of these genetic variations without associated functional or segregation data. Genotype-phenotype correlation points to 1) a more severe and earlier onset of the disease in PV and VUS carriers, underlying the importance to carry out presymptomatic diagnosis in relatives and 2) to a more prevalent left ventricular dysfunction in DSP variant carriers. This article is protected by copyright. All rights reserved.

Familial Recurrence Patterns in Congenitally Corrected Transposition of the Great Arteries: An International Study

BACKGROUND

Congenitally corrected transposition of the great arteries (ccTGA) is a rare disease of unknown cause. We aimed to better understand familial recurrence patterns.

METHODS

An international, multicentre, retrospective cohort study was conducted in 29 tertiary hospitals in 6 countries between 1990 and 2018, entailing investigation of 1043 unrelated ccTGA probands.

RESULTS

Laterality defects and atrioventricular block at diagnosis were observed in 29.9% and 9.3%, respectively. ccTGA was associated with primary ciliary dyskinesia in 11 patients. Parental consanguinity was noted in 3.4% cases. A congenital heart defect was diagnosed in 81 relatives from 69 families, 58% of them being first-degree relatives, including 28 siblings. The most prevalent defects in relatives were dextro-transposition of the great arteries (28.4%), laterality defects (13.6%), and ccTGA (11.1%); 36 new familial clusters were described, including 8 pedigrees with concordant familial aggregation of ccTGA, 19 pedigrees with familial co-segregation of ccTGA and dextro-transposition of the great arteries, and 9 familial co-segregation of ccTGA and laterality defects. In one family co-segregation of ccTGA, dextro-transposition of the great arteries and heterotaxy syndrome in 3 distinct relatives was found. In another family, twins both displayed ccTGA and primary ciliary dyskinesia.

CONCLUSIONS

ccTGA is not always a sporadic congenital heart defect. Familial clusters as well as evidence of an association between ccTGA, dextro-transposition of the great arteries, laterality defects and in some cases primary ciliary dyskinesia, strongly suggest a common pathogenetic pathway involving laterality genes in the pathophysiology of ccTGA.

Evaluation of the Post-COVID-19 Functional Status (PCFS) Scale in a cohort of patients recovering from hypoxemic SARS-CoV-2 pneumonia

Introduction

COVID-19 sequelae are numerous and multisystemic, and how to evaluate those symptomatic patients is a timely issue. Klok et al proposed the Post-COVID-19 Functional Status (PCFS) Scale as an easy tool to evaluate limitations related to persistent symptoms. Our aim was to analyse PCFS Scale ability to detect functional limitations and its correlation with quality of life in a cohort of patients, 2–9 months after hospitalisation for COVID-19 hypoxemic pneumonia.

Methods

PCFS Scale was evaluated in 121 patients together with quality of life and dyspnoea questionnaires, pulmonary function tests and CT scans.

Results

We observed a high correlation with multiple questionnaires (Short Form-36, Hospital Anxiety and Depression Scale, modified Medical Research Council, end Borg Six-Minute Walk Test), making the PCFS Scale a quick and global tool to evaluate functional limitations related to various persistent symptoms following COVID-19 pneumonia.

Discussion

The PCFS Scale seems to be a suitable instrument to screen for patients who will require careful follow-up after COVID-19 hypoxemic pneumonia even in the absence of pulmonary sequelae.

Genome-wide association analyses identify new Brugada syndrome risk loci and highlight a new mechanism of sodium channel regulation in disease susceptibility

Brugada syndrome (BrS) is a cardiac arrhythmia disorder associated with sudden death in young adults. With the exception of SCN5A, encoding the cardiac sodium channel Na_V1.5, susceptibility genes remain largely unknown. Here we performed a genome-wide association meta-analysis comprising 2,820 unrelated cases with BrS and 10,001 controls, and identified 21 association signals at 12 loci (10 new). Single nucleotide polymorphism (SNP)-heritability estimates indicate a strong polygenic influence. Polygenic risk score analyses based on the 21 susceptibility variants demonstrate varying cumulative contribution of common risk alleles among different patient subgroups, as well as genetic associations with cardiac electrical traits and disorders in the general population. The predominance of cardiac transcription factor loci indicates that transcriptional regulation is a key feature of BrS pathogenesis. Furthermore, functional studies conducted on MAPRE2, encoding the microtubule plus-end binding protein EB2, point to microtubule-related trafficking effects on Na_V1.5 expression as a new underlying molecular mechanism. Taken together, these findings broaden our understanding of the genetic architecture of BrS and provide new insights into its molecular underpinnings.

Functional Decline in COVID-19 Older Survivors Compared to Other Pneumonia Patients, a Case Control Study

OBJECTIVES

Among patients over 75 years, little is known about functional decline due to COVID-19. The aim of this study was to explore this functional decline, compare to other infectious pneumonia.

DESIGN AND SETTING

This case-control study included all COVID-19 patients hospitalized from March to December 2020 in Acute Geriatric Ward in Nantes University Hospital matched 1/1 with patients with pneumonia hospitalized in geriatric department between March 2017 and March 2019 (controls) on sex, age. Functional decline was assessed at 3 month follow up as it is routinely done after hospitalization in geriatric ward. We performed multivariable analyses to compare clinical outcomes between patients with COVID-19 vs controls.

RESULTS

132 pairs were matched on age (mean: 87 y-o), and sex (61% of women). In multivariable logistic regression analysis, there were no statistical significant association between COVID-19 infection and functional decline (OR=0.89 p=0.72). A statistical significant association was found between functional decline and Charlson comorbidity index (OR=1.17, p=0.039); prior fall (OR=2.08, p=0.012); malnutrition (OR=1.97, p=0.018); length of hospital stay (OR=1.05, p=0.002) and preadmission ADL(OR=1.25, p=0.049).

CONCLUSION

COVID-19 does not seem to be responsible for a more frequent or severe functional decline than other infectious pneumonia in older and comorbid population after 3 month follow up. In this population, pneumonia is associated with functional decline in almost 1 in 2 cases. The individual preadmission frailty seems to be a more important predictor of functional decline, encouraging multidimensional care management for this population.

Functionally validated SCN5A variants allow interpretation of pathogenicity and prediction of lethal events in Brugada syndrome

AIMS

The prognostic value of genetic variants for predicting lethal arrhythmic events (LAEs) in Brugada syndrome (BrS) remains controversial. We investigated whether the functional curation of SCN5A variations improves prognostic predictability.

METHODS AND RESULTS

Using a heterologous expression system and whole-cell patch clamping, we functionally characterized 22 variants of unknown significance (VUSs) among 55 SCN5A mutations previously curated using in silico prediction algorithms in the Japanese BrS registry (n = 415). According to the loss-of-function (LOF) properties, SCN5A mutation carriers (n = 60) were divided into two groups: LOF-SCN5A mutations and non-LOF SCN5A variations. Functionally proven LOF-SCN5A mutation carriers (n = 45) showed significantly severer electrocardiographic conduction abnormalities and worse prognosis associated with earlier manifestations of LAEs (7.9%/year) than in silico algorithm-predicted SCN5A carriers (5.1%/year) or all BrS probands (2.5%/year). Notably, non-LOF SCN5A variation carriers (n = 15) exhibited no LAEs during the follow-up period. Multivariate analysis demonstrated that only LOF-SCN5A mutations and a history of aborted cardiac arrest were significant predictors of LAEs. Gene-based association studies using whole-exome sequencing data on another independent SCN5A mutation-negative BrS cohort (n = 288) showed no significant enrichment of rare variants in 16 985 genes including 22 non-SCN5A BrS-associated genes as compared with controls (n = 372). Furthermore, rare variations of non-SCN5A BrS-associated genes did not affect LAE-free survival curves.

CONCLUSION

In vitro functional validation is key to classifying the pathogenicity of SCN5A VUSs and for risk stratification of genetic predictors of LAEs. Functionally proven LOF-SCN5A mutations are genetic burdens of sudden death in BrS, but evidence for other BrS-associated genes is elusive.

Hyponatremia is associated with poor outcome in COVID-19

Aim

Our objective was to describe the impact of hyponatremia on the outcomes of COVID-19 patients [outcomes selected: intensive care unit (ICU) admission, mechanical ventilation or death].

Methods

Two groups of COVID-19 patients were retrospectively screened on the basis of plasma sodium level at admission: hyponatremic (sodium < 135 mM, n = 92) or normonatremic (sodium ≥ 135 mM, n = 198) patients. Pearson’s chi-² (qualitative variables) and Student’s T tests (quantitative variables) were used to compare the two groups. A multiple logistic regression model was used to explore the association between patients’ clinical data and outcomes.

Results

Hyponatremia was frequent but generally mild. There were more male patients in the hyponatremic group (p = 0.014). Pulmonary lesions on the first thoracic CT-scan performed during hospitalization were significantly more extensive in the hyponatremic group (p = 0.010). ICU admission, mechanical ventilation or death were significantly more frequent in hyponatremic compared to normonatremic patients (37 versus 14%; p < 0.001; 17 versus 6%; p = 0.003; 18 versus 9%, p = 0.042, respectively). Hyponatremia was an independent predictor of adverse outcomes (adjusted Odds-ratio: 2.77 [1.26–6.15, p = 0.011]).

Conclusions

Our study showed an independent relationship between hyponatremia at admission and transfer to ICU, use of mechanical ventilation or death in COVID-19 patients. Hyponatremia may reflect the severity of underlying pulmonary lesions. Our results support the use of sodium levels as a simple bedside screening tool for the early identification of SARS-CoV-2 infected patients at high risk of poor outcome.

The added value of contrast-enhanced cardiac magnetic resonance to predict positive genetic testing in clinically suspected Lamin A/C cardiomyopathy

Funding Acknowledgements

Type of funding sources: None.

Background

Lamin A/C cardiomyopathy (CM) is an inherited disease due to LMNA gene mutation with particular phenotype that associates conduction disorders, frequent atrial fibrillation and life-threatening ventricular arrhythmias, with normal or altered ventricular systolic function. Cardiac magnetic resonance (CMR) studies suggest frequent late gadolinium enhancement (LGE) involving septal mid-myocardium. 

Aims

To assess the added value of CMR to conventional clinical features of Lamin A/C CM for the prediction of a positive LMNA gene testing. 

Methods

We performed a retrospective monocentric study in all index patients referred for genetic testing for a clinical suspicion of Lamin A/C CM. Clinical, ECG and imaging data including CMR at time of genetic testing in patients with a positive test (LMNA+) and patients without (LMNA-) were compared. The diagnostic performances of relevant parameters for the prediction of a positive LMNA gene testing were analyzed in several logistic regression models. 

Results

90 patients were included (55 LMNA+, 35 LMNA-).49% had significant left ventricular (LV) dilatation on echocardiography,57% had a LV ejection fraction (LVEF)&lt;50%, 46% had a significant left atrial dilatation, and 17% had right ventricular dysfunction. None of these parameters were different comparing LMNA+ and LMNA- patients. LMNA+ patients had significantly more frequent familial history of sudden cardiac death (SCD) or CM. There were no significant differences between LMNA+ and LMNA- patients in terms of conduction disorders, ventricular and supra-ventricular arrhythmias. The only significant difference on ECG was a more frequent abnormal R-wave progression in V1-V3 in LMNA+ patients (87.8% vs 39.4%, p &lt; 0.001). 55 patients had a CMR (28/55 LMNA+, 27/35 LMNA-). The main reason for not performing CMR was the presence of cardiac implantable electronic device. LMNA+ patients had significantly more LGE than LMNA- (20/28 (71%) vs 9/27 (33%), p = 0.011). The main differences in LGE features between the 2 groups were septal involvement (70% in LMNA+ vs 11% in LMNA-, p = 0.005) and mid-myocardium localization (95% vs 44%, p = 0.005). In a first logistic regression model without CMR data in all 90 patients, V1-V3 R-wave abnormalities, familial history of SCD and sinus node dysfunction were independent predictors of a positive LMNA gene testing (Sensitivity 89%, specificity 46%, accuracy 72%). A second model in the 55 patients who had a CMR showed better accuracy (85%), mainly driven by increased specificity (81%) with preserved sensitivity (89%). V1-V3 R-wave abnormalities, premature ventricular contractions, non-depressed LVEF and septal LGE predicted positive LMNA gene testing in this model (Septal LGE OR = 31, 95%CI 4-715; p = 0.005). 

Conclusion

CMR, particularly septal mid-myocardium LGE, carries good diagnostic accuracy to predict a positive LMNA gene testing in clinically suspected Lamin A/C CM with increased specificity when added to conventional red flags.

Abstract Figure. Logistic regression models performances

Location of intracranial aneurysms is the main factor associated with rupture in the ICAN population

BACKGROUND AND PURPOSE

The ever-growing availability of imaging led to increasing incidentally discovered unruptured intracranial aneurysms (UIAs). We leveraged machine-learning techniques and advanced statistical methods to provide new insights into rupture intracranial aneurysm (RIA) risks.

METHODS

We analysed the characteristics of 2505 patients with intracranial aneurysms (IA) discovered between 2016 and 2019. Baseline characteristics, familial history of IA, tobacco and alcohol consumption, pharmacological treatments before the IA diagnosis, cardiovascular risk factors and comorbidities, headaches, allergy and atopy, IA location, absolute IA size and adjusted size ratio (aSR) were analysed with a multivariable logistic regression (MLR) model. A random forest (RF) method globally assessed the risk factors and evaluated the predictive capacity of a multivariate model.

RESULTS

Among 994 patients with RIA (39.7%) and 1511 patients with UIA (60.3 %), the MLR showed that IA location appeared to be the most significant factor associated with RIA (OR, 95% CI: internal carotid artery, reference; middle cerebral artery, 2.72, 2.02-3.58; anterior cerebral artery, 4.99, 3.61-6.92; posterior circulation arteries, 6.05, 4.41-8.33). Size and aSR were not significant factors associated with RIA in the MLR model and antiplatelet-treatment intake patients were less likely to have RIA (OR: 0.74; 95% CI: 0.55-0.98). IA location, age, following by aSR were the best predictors of RIA using the RF model.

CONCLUSIONS

The location of IA is the most consistent parameter associated with RIA. The use of 'artificial intelligence' RF helps to re-evaluate the contribution and selection of each risk factor in the multivariate model.

The Caspase-1/IL-18 Axis of the Inflammasome in Tumor Cells: A Modulator of the Th1/Tc1 Response of Tumor-Infiltrating T Lymphocytes in Colorectal Cancer

In colorectal cancer (CRC), a high density of T lymphocytes represents a strong prognostic marker in subtypes of CRC. Optimized immunotherapy strategies to boost this T-cell response are still needed. A good candidate is the inflammasome pathway, an emerging player in cancer immunology that bridges innate and adaptive immunity. Its effector protein caspase-1 matures IL-18 that can promote a T-helper/cytotoxic (Th1/Tc1) response. It is still unknown whether tumor cells from CRC possess a functional caspase-1/IL-18 axis that could modulate the Th1/Tc1 response. We used two independent cohorts of CRC patients to assess IL-18 and caspase-1 expression by tumor cells in relation to the density of TILs and the microsatellite status of CRC. Functional and multiparametric approaches at the protein and mRNA levels were performed on an ex vivo CRC explant culture model. We show that, in the majority of CRCs, tumor cells display an activated and functional caspase-1/IL-18 axis that contributes to drive a Th1/Tc1 response elicited by TILs expressing IL-18Rα. Furthermore, unsupervised clustering identified three clusters of CRCs according to the caspase-1/IL-18/TIL density/interferon gamma (IFNγ) axis and microsatellite status. Together, our results strongly suggest that targeting the caspase-1/IL-18 axis can improve the anti-tumor immune response in subgroups of CRC.

Prediction of Unruptured Intracranial Aneurysm Evolution: The UCAN Project

BACKGROUND

Management of small (<7 mm) unruptured intracranial aneurysms (UIA) remains controversial. Retrospective studies have suggested that post gadolinium arterial wall enhancement (AWE) of UIA on magnetic resonance imaging (MRI) may reflect aneurysm wall instability, and hence may highlight a higher risk of UIA growth. This trial aims at exploring wall imaging findings of UIAs with consecutive follow-up to substantiate these assumptions.

OBJECTIVE

To develop diagnostic and predictive tools for the risk of IA evolution. Our aim is to demonstrate in clinical practice the predictive value of AWE for UIA growth. The growth will be determined by any modification of the UIA measurement. UIA growth and the UIA wall enhancement will be assessed in consensus by 2 expert neuroradiologists.

METHODS

The French prospective UCAN project is a noninterventional international wide and multicentric cohort. UIA of bifurcation between 3 and 7 mm for whom a clinical and imaging follow-up without occlusion treatment was scheduled by local multidisciplinary staff will be included. Extensive clinical, biological, and imaging data will be recorded during a 3-yr follow-up.

EXPECTED OUTCOMES

Discovering to improve the efficiency of UIA follow-up by identifying additional clinical, imaging, biological, and anatomic risk factors of UIA growth.

DISCUSSION

A prospective nationwide recruitment allows for the inclusion of a large cohort of patients with UIA. It will combine clinical phenotyping and specific imaging with AWE screening. It will enable to exploit metadata and to explore some pathophysiological pathways by crossing clinical, genetic, biological, and imaging information.

Association of Preoperative Geriatric Assessment With Length of Stay After Combined Cardiac Surgery

BACKGROUND

For older patients undergoing cardiac surgery, geriatric factors are known to increase postoperative complications and prolong length of stay (LOS). Comprehensive geriatric assessment (CGA) is an evidence-based method for geriatric evaluation to develop an individualized-care plan to optimize physical, functional, and social issues. This study analyzed the association between preoperative CGA and hospital LOS after combined cardiac surgery.

METHODS

This retrospective monocentric study included all patients aged 75 years and greater who underwent combined cardiac surgery between 2014 and 2017. Hospital LOS, intensive care unit LOS, and postoperative complications were compared between patients with or without preoperative CGA before and after propensity-score matching.

RESULTS

Mean age of the 407 patients was 79.6 years; 114 underwent a preoperative CGA (28%). For 305 patients (74.9%), coronary artery bypass was associated with aortic valve replacement. After propensity-score matching, a significant difference was found between the 2 groups (preoperative CGA versus none) for in-hospital LOS (12 versus 13 days; P = .04) and intensive care unit LOS (3 versus 4 days; P = .01). In multivariable analysis, a significant association remained between hospital LOS and CGA (P = .02), renal function (P = .02), mitral replacement (P = .001), and complications (P = .001).

CONCLUSIONS

Our results favor the use of systematic preoperative CGA. These encouraging results need to be validated by prospective studies that assess the impact of individualized-care plan established after CGA on postoperative outcomes. With an aging population, efforts are required to determine how to implement preoperative individualized-care plans to improve postoperative outcomes for vulnerable patients undergoing cardiac surgery.

Heritability of aortic valve stenosis and evidence of bicuspid enrichment in families with tricuspid aortic valve stenosis

Background

Calcific aortic valve stenosis (CAVS) is the most common valvular heart disease. Although a familial component has been described, the heritability remains unknown. This study aimed to determine the heritability of CAVS and to compare the prevalence of bicuspid aortic valve (BAV) relatives among families with tricuspid and bicuspid aortic valve phenotype and to a control cohort.

Methods

Probands were recruited following aortic valve replacement in three French university hospitals. All relatives who agreed to participate were enrolled in the study. Families were defined as tricuspid aortic valve (TAV) or BAV families based on the aortic valve phenotype observed in the proband. As control group, we used probands diagnosed with mitral valve prolapse and their families. All recruited probands and relatives underwent comprehensive transthoracic echocardiography to determine aortic valve morphology and CAVS status. Additive genetic heritability was performed with SOLAR genetic statistics package. Prevalence of BAV relatives in each sub-group and Prevalence Ratio were calculated.

Results

Within the 2371 relatives coming from 138 CAVS families, the heritability of CAVS was significant (h2=0.49, p&lt;0.001). Furthermore, TAV stenosis heritability was only significant in TAV families (h2=0.20, p=0.013). The prevalence of BAV was significantly higher in TAV families and BAV families than control families (5.96 [95% CI: 4.2–8.3%], [n=32 of 537] vs. 2.49 [95% CI: 1.3–4.7%], [n=9 of 361]; PR 2.64 [95% CI: 1.41–5.91]; p=0.005 and 10.20 [95% CI: 7.0–14.5%], [n=26 of 255] vs. 2.49 [95% CI: 1.3–4.7%], [n=9 of 361]; PR 4.63 [95% CI: 2.35–13.44]; p&lt;0.001; respectively).

Conclusions

The heritability of aortic valve stenosis in this population confirms the genetic effect in determining aortic stenosis for all aortic valve phenotype and for tricuspid aortic valve. The bicuspid enrichment in TAV families suggests common genetic predisposition of aortic valve stenosis in some families. Taking all together, these findings encourage echocardiography screening of relatives of affected individuals.

Funding Acknowledgement

Type of funding source: None

The added value of contrast-enhanced cardiac magnetic resonance to predict positive genetic testing in clinically suspected Lamin A/C cardiomyopathy

Background

Lamin A/C cardiomyopathy (CM) is an inherited disease due to LMNA gene mutation with particular phenotype that associates conduction disorders, frequent atrial fibrillation and life-threatening ventricular arrhythmias, with normal or altered ventricular systolic function. Cardiac magnetic resonance (CMR) studies suggest frequent late gadolinium enhancement (LGE) involving septal mid-myocardium.

Aims

To assess the added value of CMR to conventional clinical features of Lamin A/C CM for the prediction of a positive LMNA gene testing.

Methods

We performed a retrospective monocentric study in all index patients referred for genetic testing for a clinical suspicion of Lamin A/C CM. Clinical, ECG and imaging data including CMR at time of genetic testing in patients with a positive test (LMNA+) and patients without (LMNA-) were compared. The diagnostic performances of relevant parameters for the prediction of a positive LMNA gene testing were analyzed in several logistic regression models.

Results

90 patients were included (55 LMNA+, 35 LMNA-).49% had significant left ventricular (LV) dilatation on echocardiography,57% had a LV ejection fraction (LVEF)&lt;50%, 46% had a significant left atrial dilatation, and 17% had right ventricular dysfunction. None of these parameters were different comparing LMNA+ and LMNA- patients. LMNA+ patients had significantly more frequent familial history of sudden cardiac death (SCD) or CM. There were no significant differences between LMNA+ and LMNA- patients in terms of conduction disorders, ventricular and supra-ventricular arrhythmias. The only significant difference on ECG was a more frequent abnormal R-wave progression in V1-V3 in LMNA+ patients (87.8% vs 39.4%, p&lt;0.001). 55 patients had a CMR (28/55 LMNA+, 27/35 LMNA-). The main reason for not performing CMR was the presence of cardiac implantable electronic device. LMNA+ patients had significantly more LGE than LMNA- (20/28 (71%) vs 9/27 (33%), p=0.011). The main differences in LGE features between the 2 groups were septal involvement (70% in LMNA+ vs 11% in LMNA-, p=0.005) and mid-myocardium localization (95% vs 44%, p=0.005). In a first logistic regression model without CMR data in all 90 patients, V1-V3 R-wave abnormalities, familial history of SCD and sinus node dysfunction were independent predictors of a positive LMNA gene testing (Sensitivity 89%, specificity 46%, accuracy 72%). A second model in the 55 patients who had a CMR showed better accuracy (85%), mainly driven by increased specificity (81%) with preserved sensitivity (89%). V1-V3 R-wave abnormalities, premature ventricular contractions, non-depressed LVEF and septal LGE predicted positive LMNA gene testing in this model (Septal LGE OR=31, 95% CI 4–715; p=0.005).

Conclusion

CMR, particularly septal mid-myocardium LGE, carries good diagnostic accuracy to predict a positive LMNA gene testing in clinically suspected Lamin A/C CM with increased specificity when added to conventional red flags.

Funding Acknowledgement

Type of funding source: None

RRAD mutation causes electrical and cytoskeletal defects in cardiomyocytes derived from a familial case of Brugada syndrome

AIMS

The Brugada syndrome (BrS) is an inherited cardiac disorder predisposing to ventricular arrhythmias. Despite considerable efforts, its genetic basis and cellular mechanisms remain largely unknown. The objective of this study was to identify a new susceptibility gene for BrS through familial investigation.

METHODS AND RESULTS

Whole-exome sequencing performed in a three-generation pedigree with five affected members allowed the identification of one rare non-synonymous substitution (p.R211H) in RRAD, the gene encoding the RAD GTPase, carried by all affected members of the family. Three additional rare missense variants were found in 3/186 unrelated index cases. We detected higher levels of RRAD transcripts in subepicardium than in subendocardium in human heart, and in the right ventricle outflow tract compared to the other cardiac compartments in mice. The p.R211H variant was then subjected to electrophysiological and structural investigations in human cardiomyocytes derived from induced pluripotent stem cells (iPSC-CMs). Cardiomyocytes derived from induced pluripotent stem cells from two affected family members exhibited reduced action potential upstroke velocity, prolonged action potentials and increased incidence of early afterdepolarizations, with decreased Na+ peak current amplitude and increased Na+ persistent current amplitude, as well as abnormal distribution of actin and less focal adhesions, compared with intra-familial control iPSC-CMs Insertion of p.R211H-RRAD variant in control iPSCs by genome editing confirmed these results. In addition, iPSC-CMs from affected patients exhibited a decreased L-type Ca2+ current amplitude.

CONCLUSION

This study identified a potential new BrS-susceptibility gene, RRAD. Cardiomyocytes derived from induced pluripotent stem cells expressing RRAD variant recapitulated single-cell electrophysiological features of BrS, including altered Na+ current, as well as cytoskeleton disturbances.

Genetic Association Analyses Highlight IL6, ALPL, and NAV1 As 3 New Susceptibility Genes Underlying Calcific Aortic Valve Stenosis

BACKGROUND

Calcific aortic valve stenosis (CAVS) is a frequent and life-threatening cardiovascular disease for which there is currently no medical treatment available. To date, only 2 genes, LPA and PALMD, have been identified as causal for CAVS. We aimed to identify additional susceptibility genes for CAVS.

METHODS

A GWAS (genome-wide association study) meta-analysis of 4 cohorts, totaling 5115 cases and 354 072 controls of European descent, was performed. A TWAS (transcriptome-wide association study) was completed to integrate transcriptomic data from 233 human aortic valves. A series of post-GWAS analyses were performed, including fine-mapping, colocalization, phenome-wide association studies, pathway, and tissue enrichment as well as genetic correlation with cardiovascular traits.

RESULTS

In the GWAS meta-analysis, 4 loci achieved genome-wide significance, including 2 new loci: IL6 (interleukin 6) on 7p15.3 and ALPL (alkaline phosphatase) on 1p36.12. A TWAS integrating gene expression from 233 human aortic valves identified NAV1 (neuron navigator 1) on 1q32.1 as a new candidate causal gene. The CAVS risk alleles were associated with higher mRNA expression of NAV1 in valve tissues. Fine-mapping identified rs1800795 as the most likely causal variant in the IL6 locus. The signal identified colocalizes with the expression of the IL6 RNA antisense in various tissues. Phenome-wide association analyses in the UK Biobank showed colocalized associations between the risk allele at the IL6 lead variant and higher eosinophil count, pulse pressure, systolic blood pressure, and carotid artery procedures, implicating modulation of the IL6 pathways. The risk allele at the NAV1 lead variant colocalized with higher pulse pressure and higher prevalence of carotid artery stenosis. Association results at the genome-wide scale indicated genetic correlation between CAVS, coronary artery disease, and cardiovascular risk factors.

CONCLUSIONS

Our study implicates 3 new genetic loci in CAVS pathogenesis, which constitute novel targets for the development of therapeutic agents.

New insights into mitral valve dystrophy: a Filamin-A genotype-phenotype and outcome study

Aims

Filamin-A (FLNA) was identified as the first gene of non-syndromic mitral valve dystrophy (FLNA-MVD). We aimed to assess the phenotype of FLNA-MVD and its impact on prognosis.

Methods and results

We investigated the disease in 246 subjects (72 mutated) from four FLNA-MVD families harbouring three different FLNA mutations. Phenotype was characterized by a comprehensive echocardiography focusing on mitral valve apparatus in comparison with control relatives. In this X-linked disease valves lesions were severe in men and moderate in women. Most men had classical features of mitral valve prolapse (MVP), but without chordal rupture. By contrast to regular MVP, mitral leaflet motion was clearly restricted in diastole and papillary muscles position was closer to mitral annulus. Valvular abnormalities were similar in the four families, in adults and young patients from early childhood suggestive of a developmental disease. In addition, mitral valve lesions worsened over time as encountered in degenerative conditions. Polyvalvular involvement was frequent in males and non-diagnostic forms frequent in females. Overall survival was moderately impaired in men (P = 0.011). Cardiac surgery rate (mainly valvular) was increased (33.3 ± 9.8 vs. 5.0 ± 4.9%, P < 0.0001; hazard ratio 10.5 [95% confidence interval: 2.9-37.9]) owing mainly to a lifetime increased risk in men (76.8 ± 14.1 vs. 9.1 ± 8.7%, P < 0.0001).

Conclusion

FLNA-MVD is a developmental and degenerative disease with complex phenotypic expression which can influence patient management. FLNA-MVD has unique features with both MVP and paradoxical restricted motion in diastole, sub-valvular mitral apparatus impairment and polyvalvular lesions in males. FLNA-MVD conveys a substantial lifetime risk of valve surgery in men.

Rare Coding Variants in ANGPTL6 Are Associated with Familial Forms of Intracranial Aneurysm

Intracranial aneurysms (IAs) are acquired cerebrovascular abnormalities characterized by localized dilation and wall thinning in intracranial arteries, possibly leading to subarachnoid hemorrhage and severe outcome in case of rupture. Here, we identified one rare nonsense variant (c.1378A>T) in the last exon of ANGPTL6 (Angiopoietin-Like 6)-which encodes a circulating pro-angiogenic factor mainly secreted from the liver-shared by the four tested affected members of a large pedigree with multiple IA-affected case subjects. We showed a 50% reduction of ANGPTL6 serum concentration in individuals heterozygous for the c.1378A>T allele (p.Lys460Ter) compared to relatives homozygous for the normal allele, probably due to the non-secretion of the truncated protein produced by the c.1378A>T transcripts. Sequencing ANGPTL6 in a series of 94 additional index case subjects with familial IA identified three other rare coding variants in five case subjects. Overall, we detected a significant enrichment (p = 0.023) in rare coding variants within this gene among the 95 index case subjects with familial IA, compared to a reference population of 404 individuals with French ancestry. Among the 6 recruited families, 12 out of 13 (92%) individuals carrying IA also carry such variants in ANGPTL6, versus 15 out of 41 (37%) unaffected ones. We observed a higher rate of individuals with a history of high blood pressure among affected versus healthy individuals carrying ANGPTL6 variants, suggesting that ANGPTL6 could trigger cerebrovascular lesions when combined with other risk factors such as hypertension. Altogether, our results indicate that rare coding variants in ANGPTL6 are causally related to familial forms of IA.

DoEstRare: A statistical test to identify local enrichments in rare genomic variants associated with disease

Next-generation sequencing technologies made it possible to assay the effect of rare variants on complex diseases. As an extension of the "common disease-common variant" paradigm, rare variant studies are necessary to get a more complete insight into the genetic architecture of human traits. Association studies of these rare variations show new challenges in terms of statistical analysis. Due to their low frequency, rare variants must be tested by groups. This approach is then hindered by the fact that an unknown proportion of the variants could be neutral. The risk level of a rare variation may be determined by its impact but also by its position in the protein sequence. More generally, the molecular mechanisms underlying the disease architecture may involve specific protein domains or inter-genic regulatory regions. While a large variety of methods are optimizing functionality weights for each single marker, few evaluate variant position differences between cases and controls. Here, we propose a test called DoEstRare, which aims to simultaneously detect clusters of disease risk variants and global allele frequency differences in genomic regions. This test estimates, for cases and controls, variant position densities in the genetic region by a kernel method, weighted by a function of allele frequencies. We compared DoEstRare with previously published strategies through simulation studies as well as re-analysis of real datasets. Based on simulation under various scenarios, DoEstRare was the sole to consistently show highest performance, in terms of type I error and power both when variants were clustered or not. DoEstRare was also applied to Brugada syndrome and early-onset Alzheimer's disease data and provided complementary results to other existing tests. DoEstRare, by integrating variant position information, gives new opportunities to explain disease susceptibility. DoEstRare is implemented in a user-friendly R package.

Testing the burden of rare variation in arrhythmia-susceptibility genes provides new insights into molecular diagnosis for Brugada syndrome

The Brugada syndrome (BrS) is a rare heritable cardiac arrhythmia disorder associated with ventricular fibrillation and sudden cardiac death. Mutations in the SCN5A gene have been causally related to BrS in 20-30% of cases. Twenty other genes have been described as involved in BrS, but their overall contribution to disease prevalence is still unclear. This study aims to estimate the burden of rare coding variation in arrhythmia-susceptibility genes among a large group of patients with BrS. We have developed a custom kit to capture and sequence the coding regions of 45 previously reported arrhythmia-susceptibility genes and applied this kit to 167 index cases presenting with a Brugada pattern on the electrocardiogram as well as 167 individuals aged over 65-year old and showing no history of cardiac arrhythmia. By applying burden tests, a significant enrichment in rare coding variation (with a minor allele frequency below 0.1%) was observed only for SCN5A, with rare coding variants carried by 20.4% of cases with BrS versus 2.4% of control individuals (P = 1.4 × 10(-7)). No significant enrichment was observed for any other arrhythmia-susceptibility gene, including SCN10A and CACNA1C. These results indicate that, except for SCN5A, rare coding variation in previously reported arrhythmia-susceptibility genes do not contribute significantly to the occurrence of BrS in a population with European ancestry. Extreme caution should thus be taken when interpreting genetic variation in molecular diagnostic setting, since rare coding variants were observed in a similar extent among cases versus controls, for most previously reported BrS-susceptibility genes.

The effects of the macro-environment on treatment retention for problem cocaine users

BACKGROUND

Client dropout is commonly used as an indicator of quality and effectiveness of drug treatment. Following increasing cocaine use in recent years, research has attempted to identify predictors of retention in treatment for cocaine users but there is no consensus about how individual characteristics and system variables (referral source, treatment setting), what we term here as the "macro-environment" - effect risk of dropout. This study sought to identify macro-environmental factors and examine the way these impact upon treatment retention.

METHODS

A retrospective longitudinal study of an admission cohort among drug services in Vasta Romagna in Emilia Romagna Region, Italy (up to 8 years of treatment or until discharge) was conducted to determine the effect of macro-environmental variables on retention among first time admitted cocaine-dependent clients in different treatment settings. The sample consisted of 1178 clients meeting DSM-IV-R criteria for cocaine dependence.

RESULTS

The joint effect of individual and system factors had a significant impact on dropout rates. In particular, lower rates of dropout were observed for those treated in prison and those who had a stable home, HR: 0.09 (0.02-0.48), or lived in rehabilitation units, HR: 0.36 (0.15-0.88), and among clients referred by the local authority and those living with parents, HR: 0.60 (0.38-0.95).

CONCLUSION

The combined effect of individual and system factors on retention in treatment sets a critical background necessary to assess any impact of organizational dynamics and delineate the trajectory for future interventions.