Influence of sex on cardiovascular outcomes in RBM20 variant carriers

Background

Variants in the RBM20 gene cause dilated cardiomyopathy and may be associated with a poor prognosis.

Objectives

To determine disease penetrance, the risk of adverse events and the influence of sex on outcomes in RBM20 variant carriers.

Methods

Consecutive probands and relatives carrying pathogenic or likely pathogenic RBM20 variants were retrospectively recruited from 12 cardiomyopathy units. The primary endpoint was a composite of malignant ventricular arrhythmia (MVA) and end-stage heart failure (ESHF). MVA and ESHF endpoints were also analysed separately and males and females compared.

Results

Longitudinal follow-up data were available for 163 RBM20 variant carriers (82 male, median age 36.5 years, median follow-up 77.6 months). 10/163 had an MVA event at baseline. 30/153 without baseline MVA (19.6%) reached the primary endpoint with a trend towards worse outcomes in males (p=0.08). 16/153 (10.5%) had new MVA with no difference between males and females (p=0.92). 20/163 (12.2%) developed ESHF (17 males and 3 females; p<0.001).

By the end of follow-up, 114 patients (70%) had either left ventricular systolic dysfunction (LVSD) or had experienced MVA. 22 patients received a first diagnosis of LVSD during follow-up. Disease penetrance in individuals over 40 years of age was 78.5% by last evaluation.

Eleven patients that reached the MVA endpoint had a left ventricular ejection fraction (LVEF) available within 6 months of the event. Median [IQR] contemporary LVEF was 30% [23.75, 40%]. 5/11 patients had a contemporary LVEF >35%. 1/11 had a contemporary LVEF >45% (a female, 1st degree relative presenting with sustained ventricular tachycardia and an LVEF of 65%).

Conclusions

RBM20 variants are highly penetrant. The risk of MVA in male and female RBM20 variant carriers is similar but male sex is strongly associated with ESHF. MVA events occur in patients with LVEF >35%.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Clinical Research Training Fellowship

High prevalence of familial and genetic disease in children with cardiomyopathies: baseline paediatric data from the ESC EORP Cardiomyopathy and Myocarditis registry

Background

Previous studies on paediatric cardiomyopathies have provided useful information on their epidemiology and clinical presentation but have been limited by a lack of detailed data on genetic testing and aetiology.

Purpose

The purpose of this study was to examine the frequency of familial and genetic disease among children with cardiomyopathy enrolled in the European Society of Cardiology (ESC) Cardiomyopathy and Myocarditis EORP Long-Term Registry (CMY-LT).

Methods

633 individuals aged <18 years with hypertrophic cardiomyopathy [HCM; n=387 (61%)], dilated cardiomyopathy (DCM; n=205 (33%)], restrictive cardiomyopathy [RCM; n=28 (4%)] and arrhythmogenic right ventricular cardiomyopathy [ARVC; n=11 (2%)] were enrolled by 26 centres from 14 countries. Mean age at diagnosis was 5.2 (±5.4) years and there was a male predominance [n=372 (59%)] across all cardiomyopathy subtypes, with the exception of DCM in those diagnosed <10 years of age (p=0.005). 541 (87%) were probands compared to 83 (13%) first-degree relatives.

Results

Overall, 253 patients (47% of those reported) had familial disease; in those diagnosed between 10 and 18 years of age, familial disease was most frequent in HCM and least frequent in DCM [57 (55%) vs 12 (32%); p=0.046]. Genetic testing was performed in 414 (68%) patients. In those diagnosed <10 years, genetic testing was more frequently performed in HCM [128 (67%) vs 33 (37%) in DCM, 10 (56%) in RCM and 1 (50%) in ARVC; p=0.008]; in those aged 10–18, genetic testing was most frequent in ARVC [n=8 (89%)] followed by HCM [n=81 (69%)], RCM [n=1 (50%)] and DCM [n=22 (46%); p=0.007]. A causative mutation was reported in 250 patients (60%), with a higher yield in those aged 10–18 vs <10 years [77 (69%) vs 172 (57%), p=0.032]. In those <10 years, the prevalence of reported causative mutations was highest in HCM [128 (67%) vs 10 (56%) in RCM, 1 (50%) in ARVC and 33 (37%) in DCM; p<0.001]; in those 10–18 years, there was no significant difference in prevalence of reported causative variants between cardiomyopathy subtypes. Rare disease phenocopies were reported in 171 patients (27%): malformation syndromes [n=75 (12%)]; neuromuscular disorders [n=49 (8%)]; inborn errors of metabolism [n=20 (3%)]; mitochondrial [n=18 (3%)]; and chromosomal [n=15 (2%)]. Phenocopies were reported most frequently in patients <10 years [135 (30%) vs 35 (20%) in those aged 10–18 years; p=0.008], particularly in HCM in those <10 years [n=110 (41%); p<0.001 vs other subtypes] and DCM in those aged 10–18 years [n=18 (38%); p=0.03 vs other subtypes].

Conclusion

This study confirms the heterogeneous aetiology of childhood cardiomyopathies and demonstrate a higher prevalence of familial disease than previously reported in paediatric populations. Genetic testing is performed in a high proportion of patients, with a high yield of reported causative variants.

Funding Acknowledgement

Type of funding source: None

Long term outcomes in left ventricular non-compaction

Background

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

Objectives

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

Methods

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

Results

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

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

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

Conclusions

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

Funding Acknowledgement

Type of funding source: None

[Results of 125-iodine seed implant with preplanning system in 250 patients with prostate cancer]

INTRODUCTION

We review the experience with prostate carcinoma patients treated with permanent implants of 125-I seeds and the outcome eight years after the beginning of this technique.

MATERIAL AND METHODS

From 2002 to 2007 we have performed 250 implants with LDR brachytherapy with RapidStrand(®) and preplanning system. Mean age was 68 (49-78). Mean PSA was 7.32 (2.31 - 14.6). T1-T2a was the stage in 98%, and Gleason ≤ 6 in 96%. Low risk cases were 81% and intermediate risk 19% (ten of them received 46 Gy EBRT). Hormonal treatment was used in 42%.

RESULTS

With a mean follow-up of 48 months, 14 patients (5.7%) showed biochemical failure (BF). Eleven patients (4.5%) with theoretical BF were observed and PSA decreased without treatment. Actuarial PSA relapse-free survival at 5 years was 91%, (92% low risk, 86% intermediate cases), and 92% vs 81% with PSA <10 vs >10 (p<0.05). Rectum complications were G2 in 0.6%. A urinary catheter was necessary in 6.5%. Sexual function was conserved in 60%. Mean V100 was 89% and D90 143 Gy.

CONCLUSION

The outcome of patients with low risk prostate carcinoma treated with I-125 seed is very good with very low complications rate. Cases with PSA bounces should be controlled before starting a salvage treatment.

Radiation transmission data for radionuclides and materials relevant to brachytherapy facility shielding

To address the limited availability of radiation shielding data for brachytherapy as well as some disparity in existing data, Monte Carlo simulation was used to generate radiation transmission data for 60Co, 137CS, 198Au, 192Ir 169Yb, 170Tm, 131Cs, 125I, and 103pd photons through concrete, stainless steel, lead, as well as lead glass and baryte concrete. Results accounting for the oblique incidence of radiation to the barrier, spectral variation with barrier thickness, and broad beam conditions in a realistic geometry are compared to corresponding data in the literature in terms of the half value layer (HVL) and tenth value layer (TVL) indices. It is also shown that radiation shielding calculations using HVL or TVL values could overestimate or underestimate the barrier thickness required to achieve a certain reduction in radiation transmission. This questions the use of HVL or TVL indices instead of the actual transmission data. Therefore, a three-parameter model is fitted to results of this work to facilitate accurate and simple radiation shielding calculations.

Design and evaluation of a HDR skin applicator with flattening filter

The purposes of this study are: (i) to design field flattening filters for the Leipzig applicators of 2 and 3 cm of inner diameter with the source traveling parallel to the applicator contact surface, which are accessories of the microSelectron-HDR afterloader (Nucletron, Veenendaal, The Netherlands). These filters, made of tungsten, aim to flatten the heterogeneous dose distribution obtained with the Leipzig applicators. (ii) To estimate the dose rate distributions for these Leipzig+filter applicators by means of the Monte Carlo (MC) method. (iii) To experimentally verify these distributions for prototypes of these new applicators, and (iv) to obtain the correspondence factors to measure the output of the applicators by the user using an insert into a well chamber. The MC GEANT4 code has been used to design the filters and to obtain the dose rate distributions in liquid water for the two Leipzig+filter applicators. In order to validate this specific application and to guarantee that realistic source-applicator geometry has been considered, an experimental verification procedure was implemented in this study, in accordance with the updated recommendations of the American Association of Physicists in Medicine Task Group No. 43 U1 Report. Thermoluminescent dosimeters, radiochromic film, and a pin-point ionization chamber in a plastic [polymethylmethacrylate (PMMA)] phantom were used to verify the MC results for the two applicators of a microSelectron-HDR afterloader with the mHDR-v2 source. To verify the output of the Leipzig +filter applicators, correspondence factors were deduced for the well chambers HDR100-plus (Standard Imaging, Inc., Middleton, WI) and TM33004 (PTW, Freiburg, Germany) using a specific insert for both applicators. The doses measured in the PMMA phantom agree within experimental uncertainties with the dose obtained by the MC calculations. Percentage depth dose and off-axis profiles were obtained normalized at a depth of 3 mm along the central applicator axis in a cylindrical 20 x 20 cm water phantom. A table of output factors, normalized to 1 U of source air kerma strength at this depth, is presented. Correspondence factors were obtained for the two well chambers considered. The matrix data obtained in the MC simulation with a grid separation of 0.5 mm has been used to build a data set in a convenient format to model these distributions for routine use with a brachytherapy treatment planning system.

Development of a citrus genome-wide EST collection and cDNA microarray as resources for genomic studies

A functional genomics project has been initiated to approach the molecular characterization of the main biological and agronomical traits of citrus. As a key part of this project, a citrus EST collection has been generated from 25 cDNA libraries covering different tissues, developmental stages and stress conditions. The collection includes a total of 22,635 high-quality ESTs, grouped in 11,836 putative unigenes, which represent at least one third of the estimated number of genes in the citrus genome. Functional annotation of unigenes which have Arabidopsis orthologues (68% of all unigenes) revealed gene representation in every major functional category, suggesting that a genome-wide EST collection was obtained. A Citrus clementina Hort. ex Tan. cv. Clemenules genomic library, that will contribute to further characterization of relevant genes, has also been constructed. To initiate the analysis of citrus transcriptome, we have developed a cDNA microarray containing 12,672 probes corresponding to 6875 putative unigenes of the collection. Technical characterization of the microarray showed high intra- and inter-array reproducibility, as well as a good range of sensitivity. We have also validated gene expression data achieved with this microarray through an independent technique such as RNA gel blot analysis.