Improving sudden cardiac death risk stratification in hypertrophic cardiomyopathy using established clinical variables and genetic information

BACKGROUND AND AIMS

The cardiac societies of Europe and the United States have established different risk models for preventing sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM). The aim of this study is to validate current SCD risk prediction methods in a German HCM cohort and to improve them by the addition of genotype information.

METHODS

HCM patients without prior SCD or equivalent arrhythmic events ≥ 18 years of age were enrolled in an expert cardiomyopathy center in Germany. The primary endpoint was defined as SCD/-equivalent within 5 years of baseline evaluation. 5-year SCD-risk estimates and recommendations for ICD implantations, as defined by the ESC and AHA/ACC guidelines, were analyzed. Multivariate cox proportional hazards analyses were integrated with genetic findings as additive SCD risk.

RESULTS

283 patients were included and followed for in median 5.77 years (2.92; 8.85). A disease-causing variant was found in 138 (49%) patients. 14 (5%) patients reached the SCD endpoint (5-year incidence 4.9%). Kaplan-Meier survival analysis shows significantly lower overall SCD event-free survival for patients with an identified disease-causing variant (p < 0.05). The ESC HCM Risk-SCD model showed an area-under-the-curve (AUC) of 0.74 (95% CI 0.68-0.79; p < 0.0001) with a sensitivity of 0.29 (95% CI 0.08-0.58) and specificity of 0.83 (95% CI 0.78-0.88) for a risk estimate ≥ 6%/5-years. By comparison, the AHA/ACC HCM SCD risk stratification model showed an AUC of 0.70 (95% CI 0.65-0.76; p = 0.003) with a sensitivity of 0.93 (95% CI, 0.66-0.998) and specificity of 0.28 (95% CI 0.23-0.34) at the respective cut-off. The modified SCD Risk Score with genetic information yielded an AUC of 0.76 (95% CI 0.71-0.81; p < 0.0001) with a sensitivity of 0.86 (95% CI 0.57-0.98) and specificity of 0.69 (95% CI 0.63-0.74). The number-needed-to-treat (NNT) to prevent 1 SCD event by prophylactic ICD-implantation is 13 for the ESC model, 28 for AHA/ACC and 9 for the modified Genotype-model.

CONCLUSION

This study confirms the performance of current risk models in clinical decision making. The integration of genetic findings into current SCD risk stratification methods seem feasible and can add in decision making, especially in borderline risk-groups. A subgroup of patients with high SCD risk remains unidentified by current risk scores.

Newly emerging type B insulin resistance (TBIR) during treatment with eculizumab for AQP4-IgG-positive neuromyelitis optica spectrum disorder (NMOSD): fatal outcome

BACKGROUND

Aquaporin-4 immunoglobulin G (AQP4-IgG) antibody-positive neuromyelitis optica spectrum disorders (NMOSD) are frequently associated with other autoimmune disorders, including systemic lupus erythematosus (SLE). Eculizumab (ECU) is a highly effective long-term treatment for NMOSD. However, ECU is known to increase significantly the risk of infection with encapsulated bacteria and sepsis. Recently, increased insulin resistance (IR) in patients with NMOSD has been suggested. Type B IR (TBIR) is a rare autoimmune condition often accompanying or preceding SLE. TBIR has not yet been reported in NMOSD.

OBJECTIVE

To report an ECU-treated patient with AQP4-IgG-positive NMOSD who developed fatal septic complications after the emergence of TBIR.

METHODS

Description of the clinical course over a period of 8 years.

RESULTS

A female patient was diagnosed with NMOSD at the age of 16 years. A variety of disease-modifying drugs failed to achieve sufficient disease control, resulting in severe tetraparesis. Treatment with ECU was started 6 years after NMOSD diagnosis and stabilized the disease. The patient developed TBIR 8 months after initiation of ECU therapy. Following high-dose intravenous methylprednisolone therapy for a clinical relapse and three further courses of ECU, the patient was admitted with severe pneumonia caused by the encapsulated bacterium Klebsiella pneumoniae and hypoglycemia. Despite multimodal therapy, the patient died from sepsis-related multiorgan failure 18 months after initiation of ECU.

CONCLUSIONS

TBIR should be considered as differential diagnosis in patients with NMOSD presenting with disturbed glucose metabolism, irrespective of the presence of SLE. More real-world data are needed on the risk/benefit ratio of ECU treatment in patients who have co-existing autoimmune comorbidities that may compromise immune function. Strategies to mitigate the risk of serious infection in patients treated with ECU are discussed.

Improving the sensitivity of myelin oligodendrocyte glycoprotein-antibody testing: exclusive or predominant MOG-IgG3 seropositivity-a potential diagnostic pitfall in patients with MOG-EM/MOGAD

BACKGROUND

Myelin oligodendrocyte glycoprotein antibody-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disease, MOGAD) is the most important differential diagnosis of both multiple sclerosis and neuromyelitis optica spectrum disorders. A recent proposal for new diagnostic criteria for MOG-EM/MOGAD explicitly recommends the use of immunoglobulin G subclass 1 (IgG1)- or IgG crystallizable fragment (Fc) region-specific assays and allows the use of heavy-and-light-chain-(H+L) specific assays for detecting MOG-IgG. By contrast, the utility of MOG-IgG3-specific testing has not been systematically evaluated.

OBJECTIVE

To assess whether the use of MOG-IgG3-specific testing can improve the sensitivity of MOG-IgG testing.

METHODS

Re-testing of 22 patients with a definite diagnosis of MOG-EM/MOGAD and clearly positive MOG-IgG status initially but negative or equivocal results in H+L- or Fc-specific routine assays later in the disease course (i.e. patients with spontaneous or treatment-driven seroreversion).

RESULTS

In accordance with previous studies that had used MOG-IgG1-specific assays, IgG subclass-specific testing yielded a higher sensitivity than testing by non-subclass-specific assays. Using subclass-specific secondary antibodies, 26/27 supposedly seroreverted samples were still clearly positive for MOG-IgG, with MOG-IgG1 being the most frequently detected subclass (25/27 [93%] samples). However, also MOG-IgG3 was detected in 14/27 (52%) samples (from 12/22 [55%] patients). Most strikingly, MOG-IgG3 was the predominant subclass in 8/27 (30%) samples (from 7/22 [32%] patients), with no unequivocal MOG-IgG1 signal in 2 and only a very weak concomitant MOG-IgG1 signal in the other six samples. By contrast, no significant MOG-IgG3 reactivity was seen in 60 control samples (from 42 healthy individuals and 18 patients with MS). Of note, MOG-IgG3 was also detected in the only patient in our cohort previously diagnosed with MOG-IgA+/IgG- MOG-EM/MOGAD, a recently described new disease subvariant. MOG-IgA and MOG-IgM were negative in all other patients tested.

CONCLUSIONS

In some patients with MOG-EM/MOGAD, MOG-IgG is either exclusively or predominantly MOG-IgG3. Thus, the use of IgG1-specific assays might only partly overcome the current limitations of MOG-IgG testing and-just like H+L- and Fcγ-specific testing-might overlook some genuinely seropositive patients. This would have potentially significant consequences for the management of patients with MOG-EM/MOGAD. Given that IgG3 chiefly detects proteins and is a strong activator of complement and other effector mechanisms, MOG-IgG3 may be involved in the immunopathogenesis of MOG-EM/MOGAD. Studies on the frequency and dynamics as well as the clinical and therapeutic significance of MOG-IgG3 seropositivity are warranted.

DNA-pools targeted-sequencing as a robust cost-effective method to detect rare variants: Application to dilated cardiomyopathy genetic diagnosis

Dilated cardiomyopathy (DCM) is a heart disease characterized by left ventricular dilatation and systolic dysfunction. In 30% of cases, pathogenic variants, essentially private to each patient, are identified in at least one of almost 50 reported genes. Thus, while costly, exons capture-based Next Generation Sequencing (NGS) of a targeted gene panel appears as the best strategy to genetically diagnose DCM. Here, we report a NGS strategy applied to pools of 8 DNAs from DCM patients and validate its robustness for rare variants detection at 4-fold reduced cost. Our pipeline uses Freebayes to detect variants with the expected 1/16 allele frequency. From the whole set of detected rare variants in 96 pools we set the variants quality parameters optimizing true positives calling. When compared to simplex DNA sequencing in a shared subset of 50 DNAs, 96% of SNVs/InsDel were accurately identified in pools. Extended to the 384 DNAs included in the study, we detected 100 variants (ACMG class 4 and 5), mostly in well-known morbid gene causing DCM such as TTN, MYH7, FLNC, and TNNT2. To conclude, we report an original pool-sequencing NGS method accurately detecting rare variants. This innovative approach is cost-effective for genetic diagnostic in rare diseases.

Comparative Dosimetry for Hippocampal-Avoidant Whole Brain Radiotherapy with Helical Tomotherapy and VMAT Planning Techniques

PURPOSE/OBJECTIVE(S)

The advent of hippocampal-avoidant whole brain radiotherapy (HA-WBRT) has allowed for substantial improvements in cognition without compromising the efficacy of palliative whole brain radiotherapy. Volumetric modulated arc therapy (VMAT), a form of rotational intensity-modulated radiation therapy (IMRT), allows for rapid treatment delivery and minimizes fractional treatment time. However, given the intrinsic complexity of HA-WBRT planning, standard VMAT techniques require significant departmental resources and often fail to achieve planning objectives. We hypothesize that treatment planning and delivery on a helical tomotherapy (HT) unit improves OAR dosimetry compared to standard VMAT techniques.

MATERIALS/METHODS

Patients with multiple brain metastases who received WBRT with palliative intent were included in this single institution dosimetric study. Treatment objectives and dose constraints for HA-WBRT from NRG CC001 were utilized. Three separate plans were generated for each patient including Dual-Arc Conventional VMAT (DAC), Split-Arc Partial-Field VMAT (SAPF), and HT for dosimetric comparison. VMAT plans were generated using 6-MV photon beams with a maximum dose rate of 600 MU/min with a 120-leaf MLC. DAC plans utilized 2 coplanar arcs each with jaw tracking. SAPF plans used four partial arcs, and the field size of each beam was reduced to allow the MLC to block the centrally located hippocampus without sacrificing the whole brain PTV coverage. HT plans with a dose rate of 1000MU/min and Helical Delivery mode used a 2.5cm dynamic Jaw setting. Mean differences in target volume coverage and OAR dosimetry between planning approaches were calculated. Two-tailed, paired Student's t-tests were employed to determine statistically significant differences between DAC, SAPF, and HT plans.

RESULTS

A total of 15 treatment plans were generated for five patients (5 DAC, 5 SAPF, and 5 HT plans). HT was seen to significantly reduce hippocampal D100% compared to both DAC (∆-114.16 cGy, p = 0.001) and SAPF (∆-125.76 cGy, p < 0.001). Moreover, HT hippocampal D0.03cc was significantly lower than DAC (∆-80.26 cGy p = 0.003) and SAPF (∆-174.40 cGy, p < 0.001). At the same time, PTV coverage as determined by D98% was significantly higher compared to both DAC (∆ +372.66 cGy, p = <0.001) and SAPF (∆ +304 cGy, p = <0.001).

CONCLUSION

Compared to both DAC and SAPF, HT planning for HA-WBRT provides significant improvements in target coverage and OAR sparing. Additional research is warranted to determine whether further reductions in dose to the hippocampi provide additional clinical benefit.

Robotic SBRT in Prostate Cancer Patients Younger Than 50 Years Old-Updated Results

PURPOSE/OBJECTIVE(S)

Stereotactic Body Radiation Therapy (SBRT) is a standard therapeutic option for men with prostate adenocarcinoma. The median age of prostate cancer in the US is 66 but patients as young as 35 have been reported. Many younger patients will have surgery rather than SBRT for localized prostate cancer but some will be treated with SBRT. There is a paucity of data on the outcomes of this younger subset. This study reports updated outcomes on patients younger than 50 treated with SBRT at a single institution and compares outcomes to older patients.

MATERIALS/METHODS

Between April 2006 and December 2022, 6,130 patients with prostate cancer were treated with inhomogeneous-dosed SBRT using a robotic linear accelerator. Information was available for 4,143 patients. 3568 (86.12%) of patients were treated with a median dose of 3500cGY (3500-3625) delivered over 5 consecutive fractions prescribed to the 83-85% isodose line, and the remaining 575 (13.88%) other patients receiving a median dose of 4500cGY (4500-5400) to the pelvis in conventional fractionation followed by a 3 fraction SBRT boost of 2100 cGY (1950-2100) over 3 consecutive fractions. Androgen deprivation Therapy (ADT) was prescribed in 1,035 (24.98%) of these cases. The mean age was 67.4 years old. 48 patients were younger than 50 years old (mean age 46.6). 4,095 patients were 50 or older. Patients were divided into prognostic D'Amico risk groups with 43.75%, 50.00%, 6.25% of patients falling in the low, intermediate, and high-risk stratifications in the younger cohort and 23.88%, 57.05%, 19.07% in the older cohort respectively. Pretreatment PSA was 1.72 - 43.2 (median: 5.4) in the younger group and 0.3 - 661 (median: 6.5) in the older group. In the younger group, Gleason scores were 6 in 47.92%, 7 in 47.92%, and 8-10 in 4.16%. 44 younger patients were treated with SBRT alone. 4 patients also received supplemental external beam radiation (median dose 4500cGY) and 5 patients (10.42%) received Androgen Deprivation Therapy (ADT) as part of their treatment regimen. In the older group, Gleason scores were 6 in 29.84%, 7 in 54.14%, and 8-10 in 16.02%. 3522 were treated with SBRT alone. 573 patients also received supplemental external beam radiation (median dose 4500cGY) and 1030 patients (25.15%) received Androgen Deprivation Therapy (ADT) as part of their treatment.

RESULTS

At 75 months the 6-year biochemical relapse free survival was 95.83% in younger patients compared to 98.41% in older patients using the Phoenix definition of biochemical failure. The 6-year median post treatment PSA was 0.3 in younger patients and 0.2 in the older patients. There were no significant differences in the risk stratification between the 2 groups.

CONCLUSION

This represents the largest series evaluating outcomes in very young patients treated with definitive SBRT for prostate cancer. With updated 6-year follow up, SBRT remains an effective treatment for this younger subset of patients. Continued follow up will be required to see if these results remain durable.

More than time: travel time to the delivery ward and maternal outcomes - onset of labour, postpartum haemorrhage and obstetric anal sphincter injury

BACKGROUND

Closing delivery units increases travel time for some women. Whether increased travel time is associated with maternal outcomes is important for understanding the consequences of such closures. Previous studies are limited in measuring travel time and restricted to the outcome of caesarean section.

METHODS

Our population-based cohort includes data from the Swedish Pregnancy Register for women giving birth between 2014 and 2017 (N = 364,630). We estimated travel time from home to the delivery ward using coordinate pairs of actual addresses. The association between travel time and onset of labour was modelled using multinomial logistic regression, and logistic regression was used for the outcomes postpartum haemorrhage (PPH) and obstetric anal sphincter injury (OASIS).

FINDINGS

Over three-quarters of women had ≤30 min travel time (median 13.9 min). Women who travelled ≥60 min arrived to care sooner and laboured there longer. Women with further to travel had increased adjusted odds ratio (aOR) of having an elective caesarean section (31-59 min aOR 1.11; 95% confidence interval [CI] 1.07-1.16; ≥60 min aOR 1.25; 95% CI 1.16-1.36) than spontaneous onset of labour. Women (at full term with spontaneous onset) living ≥60 min away had reduced odds of having a PPH (aOR 0.84; 95% CI 0.76-0.94) or OASIS (aOR 0.79; 95% CI 0.66-0.94).

INTERPRETATION

Longer travel time increased the odds of elective caesarean section. Women with furthest to travel arrived sooner and spent more time in care; although they had a lower risk of PPH or OASIS, they also tended to be younger, have a higher body mass index and were Nordic born.

Rubella virus infection in endothelial cells reduces angiogenesis via interferon beta-induced CXCL10

Rubella virus (RuV) infection during pregnancy can lead to abortion, stillbirth, and embryonic defects, resulting in congenital rubella syndrome (CRS). It is estimated that there are still 100,000 cases of CRS per year in developing regions with a mortality rate of over 30%. The molecular pathomechanisms remain largely unexplored. Placental endothelial cells (EC) are frequently infected with RuV. RuV reduced the angiogenic and migratory capacity of primary human EC, as confirmed by treatment of EC with serum from RuV IgM-positive patients. Next generation sequencing analysis revealed the induction of antiviral interferon (IFN) type I and III and CXCL10. The RuV-induced transcriptional profile resembled the effects of IFN-β treatment. The RuV-mediated inhibition of angiogenesis was reversed by treatment with blocking and neutralizing antibodies targeting CXCL10 and the IFN-β receptor. The data identify an important role for antiviral IFN-mediated induction of CXCL10 in the control of EC function during RuV infection.

Deep phenotyping of two preclinical mouse models and a cohort of RBM20 mutation carriers reveals no sex-dependent disease severity in RBM20 cardiomyopathy

RBM20 cardiomyopathy is an arrhythmogenic form of dilated cardiomyopathy caused by mutations in the splicing factor RBM20. A recent study found a more severe phenotype in male patients with RBM20 cardiomyopathy patients than in female patients. Here, we aim to determine sex differences in an animal model of RBM20 cardiomyopathy and investigate potential underlying mechanisms. In addition, we aim to determine sex and gender differences in clinical parameters in a novel RBM20 cardiomyopathy patient cohort. We characterized an Rbm20 knockout (KO) mouse model, and show that splicing of key RBM20 targets, cardiac function, and arrhythmia susceptibility do not differ between sexes. Next, we performed deep phenotyping of these mice, and show that male and female Rbm20-KO mice possess transcriptomic and phosphoproteomic differences. Hypothesizing that these differences may influence the heart's ability to compensate for stress, we exposed Rbm20-KO mice to acute catecholaminergic stimulation and again found no functional differences. We also replicate the lack of functional differences in a mouse model with the Rbm20-R636Q mutation. Lastly, we present a patient cohort of 33 RBM20 cardiomyopathy patients and show that these patients do not possess sex and gender differences in disease severity. Current mouse models of RBM20 cardiomyopathy show more pronounced changes in gene expression and phosphorylation of cardiac proteins in male mice, but no sex differences in cardiac morphology and function. Moreover, other than reported before, male RBM20 cardiomyopathy patients do not present with worse cardiac function in a patient cohort from Germany and the Netherlands.NEW & NOTEWORTHY Optimal management of the cardiac disease is increasingly personalized, partly because of differences in outcomes between sexes. RBM20 cardiomyopathy has been described to be more severe in male patients, and this carries the risk that male patients are more scrutinized in the clinic than female patients. Our findings do not support this observation and suggest that treatment should not differ between male and female RBM20 cardiomyopathy patients, but instead should focus on the underlying disease mechanism.

Genotype Complements the Phenotype: Identification of the Pathogenicity of an LMNA Splice Variant by Nanopore Long-Read Sequencing in a Large DCM Family

Dilated cardiomyopathy (DCM) is a common cause of heart failure (HF) and is of familial origin in 20−40% of cases. Genetic testing by next-generation sequencing (NGS) has yielded a definite diagnosis in many cases; however, some remain elusive. In this study, we used a combination of NGS, human-induced pluripotent-stem-cell-derived cardiomyocytes (iPSC-CMs) and nanopore long-read sequencing to identify the causal variant in a multi-generational pedigree of DCM. A four-generation family with familial DCM was investigated. Next-generation sequencing (NGS) was performed on 22 family members. Skin biopsies from two affected family members were used to generate iPSCs, which were then differentiated into iPSC-CMs. Short-read RNA sequencing was used for the evaluation of the target gene expression, and long-read RNA nanopore sequencing was used to evaluate the relevance of the splice variants. The pedigree suggested a highly penetrant, autosomal dominant mode of inheritance. The phenotype of the family was suggestive of laminopathy, but previous genetic testing using both Sanger and panel sequencing only yielded conflicting evidence for LMNA p.R644C (rs142000963), which was not fully segregated. By re-sequencing four additional affected family members, further non-coding LMNA variants could be detected: rs149339264, rs199686967, rs201379016, and rs794728589. To explore the roles of these variants, iPSC-CMs were generated. RNA sequencing showed the LMNA expression levels to be significantly lower in the iPSC-CMs of the LMNA variant carriers. We demonstrated a dysregulated sarcomeric structure and altered calcium homeostasis in the iPSC-CMs of the LMNA variant carriers. Using targeted nanopore long-read sequencing, we revealed the biological significance of the variant c.356+1G>A, which generates a novel 5′ splice site in exon 1 of the cardiac isomer of LMNA, causing a nonsense mRNA product with almost complete RNA decay and haploinsufficiency. Using novel molecular analysis and nanopore technology, we demonstrated the pathogenesis of the rs794728589 (c.356+1G>A) splice variant in LMNA. This study highlights the importance of precise diagnostics in the clinical management and workup of cardiomyopathies.

Decrease of RNA editing in the failing heart leads to induction of circRNAs

Background and purpose

Adenosine-to-Inosine (A-to-I) RNA editing is a post-transcriptional modification process that affects the secondary structure of RNAs. Changes in RNA editing have been associated with human diseases. We therefore aimed to analyze editing in the healthy and failing human heart.

Methods and results

Transcriptome sequencing of human heart samples of heart failure (HF) patients (n=20) and controls (n=10) revealed A-to-I editing as the major type of editing (&gt;80%). In HF patients, RNA editing was reduced, which was primarily attributable to Alu elements in introns of protein-coding genes. We identified 166 upregulated circRNAs in HF, with the majority showing reduced RNA editing in their parental host gene (88.3%). CircRNA expression did not correlate with their corresponding host gene (R=0.07, P&lt;0.05), suggesting that an alternative splicing mechanism gives rise to the elevated circRNA levels in HF. The RNA editing enzyme ADAR2, which binds to RNA regions that are edited from adenosine to inosine, was decreased in failing human hearts (−68.2%). In vitro, reduction of ADAR2 increased circRNA levels suggesting a causal effect of reduced ADAR2 levels on increased circRNAs in the failing human heart. To gain mechanistic insight, we examined the formation of circRNAs on one exemplary candidate. AKAP13 was among the top edited mRNAs in the human heart and gave rise to a circular transcript, which was elevated in HF. ADAR2 reduced the formation of double-stranded structures in AKAP13 pre-mRNA, thereby reducing the stability of Alu elements and the circularization of the resulting circRNA. Overexpression of circAKAP13 impaired the sarcomere regularity of human induced pluripotent stem cell-derived cardiomyocytes (−31.0%).

Conclusion

Our study shows that ADAR2 mediates A-to-I RNA editing in the human heart. We describe an alternative splicing mechanism of circRNAs in the human heart. In the healthy human heart, A-to-I RNA editing represses the formation of dsRNA structures of Alu elements thereby favoring linear mRNA splicing. Our results contribute to a better mechanistic understanding into the human-specific regulation of circRNA formation and are relevant to diseases with reduced RNA editing and increased circRNA levels.

Funding Acknowledgement

Type of funding sources: None.

The long non-coding RNA Heat4 is dynamically regulated during cardiogenic shock

Background and purpose

Cardiogenic shock (CS) remains the leading cause of death in acute myocardial infarction (AMI), with high mortality rates of 40–50%. The long non-coding RNA (lncRNA) Heat4 is associated with the inflammatory response of non-classical monocytes. Previous experimental work shows that this mechanism may be important in heart failure (HF) and during regeneration after vascular injury. Here, we investigate the association of Heat4 with survival in patients with chronic HF and assessed its regulation in AMI and CS.

Methods and results

Heat4 was elevated in the blood of HF patients compared to age-matched non-failing controls (+5.2-fold; HF: N=63; Controls: N=38; p&lt;0.05). Heat4 showed a positive correlation with systemic inflammation (hsCRP; r=0.41; p&lt;0.05) and was negatively associated with LVEF (r=−0.45; p&lt;0.001). Heat4 blood levels showed good discriminatory power for prevalence of HF (AUC = 0.734; p&lt;0.05) and mortality prediction after 4-year follow-up (AUC = 0.789; HF: Death N=32; Controls: Death N=0; p&lt;0.05). Furthermore, Heat4 was elevated in the blood of patients with AMI compared to controls (+1.85-fold; AMI: N=42; Controls: N=23; p&lt;0.05). Heat4 showed a very strong induction in patients suffering from CS (+284.5-fold; CS: N=4; Controls: N=5; p&lt;0.05). In agreement with an anti-inflammatory signaling, Heat4 showed a dynamic regulation in patients with CS with a 284.5-fold increase during acute shock and a decrease 24 hours after revascularization (−82.3% compared to day of revascularization). This regulation was validated in an independent second cohort.

Conclusion

The lncRNA Heat4 is upregulated in the blood of patients with chronic heart failure, acute myocardial infarction and cardiogenic shock. In CS, Heat4 is dynamically regulated. These data set the stage to further assess Heat4 blood levels as a strategy for risk stratification and potential treatment target in HF.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Projektfoerderung im Bereich der Herzmedizin, Leipzig

The long non-coding RNA Heat4 is elevated in heart failure patients and mediates anti-inflammatory functions thereby promoting vascular regeneration

Background and purpose

Activation of the immune system correlates with the severity and the prognosis of patients with heart failure (HF). Here, we aim to identify and characterize long non-coding RNAs (lncRNAs) as a potential mechanistic link between the activation of the immune system and the pathophysiology of HF.

Methods and results

Using next-generation sequencing we found a yet uncharacterized lncRNA to be significantly upregulated in peripheral blood mononuclear cells of ischemic cardiomyopathy patients compared to controls, which we named Heat4 – Heart-disease associated transcript 4 (N=4; 2.05-fold increase; p&lt;0.05). In the blood, monocytes show the highest expression of Heat4 and here in particular the non-classical monocytes compared to classical monocytes (N=4; 3.37-fold; p&lt;0.05). Matching the known anti-inflammatory properties of this monocyte subpopulation we found that overexpression of Heat4 in monocytes resulted in decreased levels of inflammation (TNFα: −38.6%; p&lt;0.05). Accordingly, a knockdown of Heat4 increased levels of inflammatory cytokine expression (TNFα: +4.14-fold; p&lt;0.05). Non-classical monocytes are known to maintain vascular homeostasis by patrolling the endothelium in search of injury. Indeed, overexpression of Heat4 in human monocytes increased vascular regeneration after injury of the carotid artery in NOD-SCID mice (N=6; +1.85-fold compared to injection of control monocytes; p&lt;0.05). We found Heat4 enriched in the cytoplasm of monocytes compared to the nuclear fraction. Using biotin-labelled RNA probes containing 2$'$O-Me-RNA oligonucleotides we performed RNA antisense affinity selection and subsequent mass spectrometry to identify proteins interacting with Heat4. We found two proteins, namely IP1 and IP2, enriched in the Heat4 fraction (+1.20 and +1.45-fold, respectively compared to the control probe). Knockdown of IP1 resulted in reduced induction of inflammatory gene expression (IL-6: −49.2%; p&lt;0.05) after stimulation of monocytes with TNFα. Mechanistically, overexpression of Heat4 resulted in reduced extracellular levels of the IP1/IP2 heterodimer (IP1/IP2: −23.6%; p&lt;0.05) as determined by ELISA.

Conclusion

The lncRNA Heat4 is elevated in the blood of patients with HF. Heat4 limits the extent of the inflammatory response of non-classical monocytes and leads to a faster regeneration after vascular injury. Heat4 is located in the cytoplasm of monocytes interacting with the pro-inflammatory proteins IP1/IP2 and repealing their extracellular release. Modulating Heat4 levels may represent a novel strategy for treatment of cardiovascular diseases with impaired vascular functions.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Projektfoerderung im Bereich der Herzmedizin, Leipzig

MOG encephalomyelitis after vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2): case report and comprehensive review of the literature

BACKGROUND

In around 20% of cases, myelin oligodendrocyte glycoprotein (MOG) immunoglobulin (IgG)-associated encephalomyelitis (MOG-EM; also termed MOG antibody-associated disease, MOGAD) first occurs in a postinfectious or postvaccinal setting.

OBJECTIVE

To report a case of MOG-EM with onset after vaccination with the Pfizer BioNTech COVID-19 mRNA vaccine BNT162b2 (Comirnaty®) and to provide a comprehensive review of the epidemiological, clinical, radiological, electrophysiological and laboratory features as well as treatment outcomes of all published patients with SARS-CoV-2 vaccination-associated new-onset MOG-EM.

METHODS

Case report and review of the literature.

RESULTS

In our patient, MOG-IgG-positive (serum 1:1000, mainly IgG1 and IgG2; CSF 1:2; MOG-specific antibody index < 4) unilateral optic neuritis (ON) occurred 10 days after booster vaccination with BNT162b2, which had been preceded by two immunizations with the vector-based Oxford AstraZeneca vaccine ChAdOx1-S/ChAdOx1-nCoV-19 (AZD1222). High-dose steroid treatment with oral tapering resulted in complete recovery. Overall, 20 cases of SARS-CoV2 vaccination-associated MOG-EM were analysed (median age at onset 43.5 years, range 28-68; female to male ratio = 1:1.2). All cases occurred in adults and almost all after immunization with ChAdOx1-S/ChAdOx1 nCoV-19 (median interval 13 days, range 7-32), mostly after the first dose. In 70% of patients, more than one CNS region (spinal cord, brainstem, supratentorial brain, optic nerve) was affected at onset, in contrast to a much lower rate in conventional MOG-EM in adults, in which isolated ON is predominant at onset and ADEM-like phenotypes are rare. The cerebrospinal fluid white cell count (WCC) exceeded 100 cells/μl in 5/14 (36%) patients with available data (median peak WCC 58 cells/μl in those with pleocytosis; range 6-720). Severe disease with tetraparesis, paraplegia, functional blindness, brainstem involvement and/or bladder/bowel dysfunction and a high lesion load was common, and treatment escalation with plasma exchange (N = 9) and/or prolonged IVMP therapy was required in 50% of cases. Complete or partial recovery was achieved in the majority of patients, but residual symptoms were significant in some. MOG-IgG remained detectable in 7/7 cases after 3 or 6 months.

CONCLUSIONS

MOG-EM with postvaccinal onset was mostly observed after vaccination with ChAdOx1-S/ChAdOx1 nCoV-19. Attack severity was often high at onset. Escalation of immunotherapy was frequently required. MOG-IgG persisted in the long term.

Abstract P2044: The Cardioprotective Egr-1 And Maladaptive Sp-1 Zinc Finger Transcription Factor Reciprocally Regulates Expression Of The Cardiomyocyte Performance Enhancing Protein S100a1

Background and Hypothesis: Expression of the cardiomyocyte (CM) protein S100A1, which improves contractile performance of the heart, sharply increases during postnatal myocardial maturation but declines rapidly in failing hearts. We therefore hypothesized that CMs are wired with transcriptional factors (TFs) that positively and negatively regulate S100A1’s gene locus activity. Understanding these reciprocal circuits may be relevant for advanced therapeutic modulation of S100A1’s abundance in diseased hearts.

Methods and Results: H9C2 rat cardiomyoblasts, an animal-free in vitro tool, displayed a strong concordant rise in S100A1 mRNA and protein levels (8.1+/-1.1 vs. cont.; n=9, p<0.05) amongst other CM markers (i.e., SERCA2a) over a 5-day CM differentiation protocol. Overall TF activity during this process was computationally inferred from TF binding site (TFBS) assessments in promoters of all actively regulated transcripts provided by a time-resolved (undifferentiated, day 0, 2 and 5) transcriptome analysis. From these TFs, EGR1 and SP1 amongst eight others were chosen due to their abundance both in differentiated H9C2-CMs and adult rat hearts and TFBS in the -1000 to +500 bp rat S100A1 gene promoter region due to a 5’ RACE-PCR based transcription start site identification in our model. To capture the relevant TFs from this group, we next co-incubated nuclear extracts from H9C2-CMs with biotinylated fragments of the aforementioned S100A1 promoter region coupled to streptavidin beads. S100A1 promoter-bound TFs were identified by mass spectrometry and only factors with a >2-fold enrichment over control were selected delivering EGR1 and SP1 as top hits. Subsequent siRNA-mediated silencing of both TFs yielded an EGR1 and SP1 knock-down dose-dependent inhibition (80%; p<0.05 vs. contr., n=9) and amplification (126%; p<0.05 vs. contr., n=9) of the rise both in S100A1 mRNA and protein levels in the H9C2-CM model that validated our comp./exp. pipeline and biological relevance of our TF hits, respectively.

Conclusion: Our study identified the known cardioprotective EGR1 and maladaptive SP1 as novel positive and negative TF regulators of CM S100A1 expression and targets for therapeutic S100A1 gene locus modulation i.e., by SP1 TFBS gene-editing.

Reduction of A-to-I RNA editing in the failing human heart regulates formation of circular RNAs

Alterations of RNA editing that affect the secondary structure of RNAs can cause human diseases. We therefore studied RNA editing in failing human hearts. Transcriptome sequencing showed that adenosine-to-inosine (A-to-I) RNA editing was responsible for 80% of the editing events in the myocardium. Failing human hearts were characterized by reduced RNA editing. This was primarily attributable to Alu elements in introns of protein-coding genes. In the failing left ventricle, 166 circRNAs were upregulated and 7 circRNAs were downregulated compared to non-failing controls. Most of the upregulated circRNAs were associated with reduced RNA editing in the host gene. ADAR2, which binds to RNA regions that are edited from A-to-I, was decreased in failing human hearts. In vitro, reduction of ADAR2 increased circRNA levels suggesting a causal effect of reduced ADAR2 levels on increased circRNAs in the failing human heart. To gain mechanistic insight, one of the identified upregulated circRNAs with a high reduction of editing in heart failure, AKAP13, was further characterized. ADAR2 reduced the formation of double-stranded structures in AKAP13 pre-mRNA, thereby reducing the stability of Alu elements and the circularization of the resulting circRNA. Overexpression of circAKAP13 impaired the sarcomere regularity of human induced pluripotent stem cell-derived cardiomyocytes. These data show that ADAR2 mediates A-to-I RNA editing in the human heart. A-to-I RNA editing represses the formation of dsRNA structures of Alu elements favoring canonical linear mRNA splicing and inhibiting the formation of circRNAs. The findings are relevant to diseases with reduced RNA editing and increased circRNA levels and provide insights into the human-specific regulation of circRNA formation.

Novel Nongenetic Murine Model of Hyperglycemia and Hyperlipidemia-Associated Aggravated Atherosclerosis

Objective

Atherosclerosis, the main pathology underlying cardiovascular diseases is accelerated in diabetic patients. Genetic mouse models require breeding efforts which are time-consuming and costly. Our aim was to establish a new nongenetic model of inducible metabolic risk factors that mimics hyperlipidemia, hyperglycemia, or both and allows the detection of phenotypic differences dependent on the metabolic stressor(s).

Methods and Results

Wild-type mice were injected with gain-of-function PCSK9^D377Y (proprotein convertase subtilisin/kexin type 9) mutant adeno-associated viral particles (AAV) and streptozotocin and fed either a high-fat diet (HFD) for 12 or 20 weeks or a high-cholesterol/high-fat diet (Paigen diet, PD) for 8 weeks. To evaluate atherosclerosis, two different vascular sites (aortic sinus and the truncus of the brachiocephalic artery) were examined in the mice. Combined hyperlipidemic and hyperglycemic (HGHCi) mice fed a HFD or PD displayed characteristic features of aggravated atherosclerosis when compared to hyperlipidemia (HCi HFD or PD) mice alone. Atherosclerotic plaques of HGHCi HFD animals were larger, showed a less stable phenotype (measured by the increased necrotic core area, reduced fibrous cap thickness, and less α-SMA-positive area) and had more inflammation (increased plasma IL-1β level, aortic pro-inflammatory gene expression, and MOMA-2-positive cells in the BCA) after 20 weeks of HFD. Differences between the HGHCi and HCi HFD models were confirmed using RNA-seq analysis of aortic tissue, revealing that significantly more genes were dysregulated in mice with combined hyperlipidemia and hyperglycemia than in the hyperlipidemia-only group. The HGHCi-associated genes were related to pathways regulating inflammation (increased Cd68, iNos, and Tnfa expression) and extracellular matrix degradation (Adamts4 and Mmp14). When comparing HFD with PD, the PD aggravated atherosclerosis to a greater extent in mice and showed plaque formation after 8 weeks. Hyperlipidemic and hyperglycemic mice fed a PD (HGHCi PD) showed less collagen (Sirius red) and increased inflammation (CD68-positive cells) within aortic plaques than hyperlipidemic mice (HCi PD). HGHCi-PD mice represent a directly inducible hyperglycemic atherosclerosis model compared with HFD-fed mice, in which atherosclerosis is severe by 8 weeks.

Conclusion

We established a nongenetically inducible mouse model allowing comparative analyses of atherosclerosis in HCi and HGHCi conditions and its modification by diet, allowing analyses of multiple metabolic hits in mice.

Doxorubicin induces cardiotoxicity in a pluripotent stem cell model of aggressive B cell lymphoma cancer patients

Cancer therapies with anthracyclines have been shown to induce cardiovascular complications. The aims of this study were to establish an in vitro induced pluripotent stem cell model (iPSC) of anthracycline-induced cardiotoxicity (ACT) from patients with an aggressive form of B-cell lymphoma and to examine whether doxorubicin (DOX)-treated ACT-iPSC cardiomyocytes (CM) can recapitulate the clinical features exhibited by patients, and thus help uncover a DOX-dependent pathomechanism. ACT-iPSC CM generated from individuals with CD20⁺ B-cell lymphoma who had received high doses of DOX and suffered cardiac dysfunction were studied and compared to control-iPSC CM from cancer survivors without cardiac symptoms. In cellular studies, ACT-iPSC CM were persistently more susceptible to DOX toxicity including augmented disorganized myofilament structure, changed mitochondrial shape, and increased apoptotic events. Consistently, ACT-iPSC CM and cardiac fibroblasts isolated from fibrotic human ACT myocardium exhibited higher DOX-dependent reactive oxygen species. In functional studies, Ca²⁺ transient amplitude of ACT-iPSC CM was reduced compared to control cells, and diastolic sarcoplasmic reticulum Ca²⁺ leak was DOX-dependently increased. This could be explained by overactive CaMKIIδ in ACT CM. Together with DOX-dependent augmented proarrhythmic cellular triggers and prolonged action potentials in ACT CM, this suggests a cellular link to arrhythmogenic events and contractile dysfunction especially found in ACT engineered human myocardium. CamKIIδ inhibition prevented proarrhythmic triggers in ACT. In contrast, control CM upregulated SERCA2a expression in a DOX-dependent manner, possibly to avoid heart failure conditions. In conclusion, we developed the first human patient-specific stem cell model of DOX-induced cardiac dysfunction from patients with B-cell lymphoma. Our results suggest that DOX-induced stress resulted in arrhythmogenic events associated with contractile dysfunction and finally in heart failure after persistent stress activation in ACT patients.

Missense Variant E1295K of Sodium Channel SCN5A Associated With Recurrent Ventricular Fibrillation and Myocardial Inflammation

SCN5A was considered an exclusively cardiac expressed ion channel but discovered to also act as a novel innate immune sensor. We report on a young SCN5A variant carrier with recurrent ventricular fibrillation and massive myocardial inflammation whose peculiar clinical course is highly suggestive of such a dual role of SCN5A. (Level of Difficulty: Advanced.)

The effect of Covid-19 mRNA vaccine on serum anti-Müllerian hormone levels

STUDY QUESTION

Does the administration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine have an association with ovarian reserve as expressed by circulating anti-Müllerian hormone (AMH) levels?

SUMMARY ANSWER

Ovarian reserve as assessed by serum AMH levels is not altered at 3 months following mRNA SARS-CoV-2 vaccination.

WHAT IS KNOWN ALREADY

A possible impact of SARS-CoV-2 infection or vaccination through an interaction between the oocyte and the somatic cells could not be ruled out, however, data are limited.

STUDY DESIGN, SIZE, DURATION

This is a prospective study conducted at a university affiliated tertiary medical center between February and March 2021.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Study population included reproductive aged women (18-42 years) that were vaccinated by two Pfizer-BioNTech Covid-19 vaccines (21 days apart). Women with ovarian failure, under fertility treatments, during pregnancy, previous Covid-19 infection or vaccinated were excluded from the study. Blood samples were collected for AMH levels before the first mRNA vaccine administration. Additional blood samples after 3 months were collected for AMH and anti-Covid-19 antibody levels. Primary outcome was defined as the absolute and percentage change in AMH levels.

MAIN RESULTS AND THE ROLE OF CHANCE

The study group consisted of 129 women who received two mRNA vaccinations. Mean AMH levels were 5.3 (±SD 4.29) µg/l and 5.3 (±SD 4.50) µg/l at baseline and after 3 months, respectively (P = 0.11). To account for possible age-specific changes of AMH, sub-analyses were performed for three age groups: <30, 30-35 and >35 years. AMH levels were significantly lower for women older than 35 years at all times (P = 0.001 for pre and post vaccination AMH levels versus younger women). However, no significant differences for the changes in AMH levels before and after vaccinations (Delta AMH) were observed for the three age groups (P = 0.46). Additionally, after controlling for age, no association was found between the degree of immunity response and AMH levels.

LIMITATIONS, REASONS FOR CAUTION

Although it was prospectively designed, for ethical reasons we could not assign a priori a randomized unvaccinated control group. This study examined plasma AMH levels at 3 months after the first vaccination. It could be argued that possible deleterious ovarian and AMH changes caused by the SARS-CoV-2 mRNA vaccinations might take effect only at a later time. Only longer-term studies will be able to examine this issue.

WIDER IMPLICATIONS OF THE FINDINGS

The results of the study provide reassurance for women hesitant to complete vaccination against Covid 19 due to concerns regarding its effect on future fertility. This information could be of significant value to physicians and patients alike.

STUDY FUNDING/COMPETING INTEREST(S)

The study was supported by Sheba Medical Center institutional sources. All authors have nothing to disclose.

TRIAL REGISTRATION NUMBER

The study protocol was approved by the 'Sheba Medical Center' Ethical Committee Review Board (ID 8121-21-SMC) on 8 February 2021 and was registered at the National Institutes of Health (NCT04748172).

Recombinant follicular stimulating hormone plus recombinant luteinizing hormone versus human menopausal gonadotropins- does the source of LH bioactivity affect ovarian stimulation outcome?

OBJECTIVE

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) activate distinct intracellular signaling cascades. However, due to their similar structure and common receptor, they are used interchangeably during ovarian stimulation (OS). This study aims to assess if the source of LH used during OS affects IVF outcome.

PATIENTS AND METHODS

This was a cross sectional study of patients who underwent two consecutive IVF cycles, one included recombinant follicular stimulating hormone (FSH) plus recombinant LH [rFSH+rLH, (Pergoveris)] and the other included urinary hCG [highly purified hMG (HP-hMG), (Menopur)]. The OS protocol, except of the LH preparation, was identical in the two IVF cycles.

RESULTS

The rate of mature oocytes was not different between the treatment cycles (0.9 in the rFSH+rLH vs 0.8 in the HP-hMG, p = 0.07). Nonetheless, the mean number of mature oocytes retrieved in the rFSH+rLH treatment cycles was higher compared to the HP-hMG treatment cycles (10 ± 5.8 vs 8.3 ± 4.6, respectively, P = 0.01). Likewise, the mean number of fertilized oocytes was higher in the rFSH+rLH cycles compared with the HP-hMG cycles (8.5 ± 5.9 vs 6.4 ± 3.6, respectively, p = 0.05). There was no difference between the treatment cycles regarding the number of top-quality embryos, the ratio of top-quality embryos per number of oocytes retrieved or fertilized oocytes or the pregnancy rate.

CONCLUSION

The differences in treatment outcome, derived by different LH preparations reflect the distinct physiological role of these molecules. Our findings may assist in tailoring a specific gonadotropin regimen when assembling an OS protocol.

Identification of SCN5a p.C335R Variant in a Large Family with Dilated Cardiomyopathy and Conduction Disease

Introduction: Familial dilated cardiomyopathy (DCM) is clinically variable and has been associated with mutations in more than 50 genes. Rapid improvements in DNA sequencing have led to the identification of diverse rare variants with unknown significance (VUS), which underlines the importance of functional analyses. In this study, by investigating human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), we evaluated the pathogenicity of the p.C335R sodium voltage-gated channel alpha subunit 5 (SCN5a) variant in a large family with familial DCM and conduction disease. Methods: A four-generation family with autosomal dominant familial DCM was investigated. Next-generation sequencing (NGS) was performed in all 16 family members. Clinical deep phenotyping, including endomyocardial biopsy, was performed. Skin biopsies from two patients and one healthy family member were used to generate human-induced pluripotent stem cells (iPSCs), which were then differentiated into cardiomyocytes. Patch-clamp analysis with Xenopus oocytes and iPSC-CMs were performed. Results: A SCN5a variant (c.1003T>C; p.C335R) could be detected in all family members with DCM or conduction disease. A novel truncating TTN variant (p.Ser24998LysfsTer28) could also be identified in two family members with DCM. Family members with the SCN5a variant (p.C335R) showed significantly longer PQ and QRS intervals and lower left ventricular ejection fractions (LV-EF). All four patients who received CRT-D were non-responders. Electrophysiological analysis with Xenopus oocytes showed a loss of function in SCN5a p.C335R. Na⁺ channel currents were also reduced in iPSC-CMs from DCM patients. Furthermore, iPSC-CM with compound heterozygosity (SCN5a p.C335R and TTNtv) showed significant dysregulation of sarcomere structures, which may be contributed to the severity of the disease and earlier onset of DCM. Conclusion: The SCN5a p.C335R variant is causing a loss of function of peak INa in patients with DCM and cardiac conduction disease. The co-existence of genetic variants in channels and structural genes (e.g., SCN5a p.C335R and TTNtv) increases the severity of the DCM phenotype.

Controlling my genome with my smartphone: first clinical experiences of the PROMISE system

Background

The development of Precision Medicine strategies requires high-dimensional phenotypic and genomic data, both of which are highly privacy-sensitive data types. Conventional data management systems lack the capabilities to sufficiently handle the expected large quantities of such sensitive data in a secure manner. PROMISE is a genetic data management concept that implements a highly secure platform for data exchange while preserving patient interests, privacy, and autonomy.

Methods

The concept of PROMISE to democratize genetic data was developed by an interdisciplinary team. It integrates a sophisticated cryptographic concept that allows only the patient to grant selective access to defined parts of his genetic information with single DNA base-pair resolution cryptography. The PROMISE system was developed for research purposes to evaluate the concept in a pilot study with nineteen cardiomyopathy patients undergoing genotyping, questionnaires, and longitudinal follow-up.

Results

The safety of genetic data was very important to 79%, and patients generally regarded the data as highly sensitive. More than half the patients reported that their attitude towards the handling of genetic data has changed after using the PROMISE app for 4 months (median). The patients reported higher confidence in data security and willingness to share their data with commercial third parties, including pharmaceutical companies (increase from 5 to 32%).

Conclusion

PROMISE democratizes genomic data by a transparent, secure, and patient-centric approach. This clinical pilot study evaluating a genetic data infrastructure is unique and shows that patient’s acceptance of data sharing can be increased by patient-centric decision-making.

Graphic abstract

The long non-coding RNA Heat4 is upregulated in heart failure and decreases the immune response of non-classical monocytes

Background and purpose

Activation of the immune system correlates with the severity and the prognosis of patients with heart failure (HF). This study aims to identify and characterize long non-coding RNAs (lncRNAs) as a potential mechanistic link between the pathophysiology of HF and the activation of the immune system.

Methods and results

Next-generation sequencing (NGS) studies identified a 2.05-fold increase of the lncRNA Heat4 in the blood of patients with HF compared to controls, which was validated in a larger cohort (HF: N=63; Controls: N=38; p&lt;0.05). Interestingly, the lncRNA Heat4 is encoded in the well-known immune receptor locus CD300, together with 8 CD300-receptors which are associated with activation of the immune system. To determine the cellular origin of Heat4 in blood, we performed MACS and identified Heat4 to be enriched in non-classical monocytes compared to classical monocytes (3.37-fold, p&lt;0.05). The expression of Heat4 in non-classical monocytes was further validated by single-cell RNA sequencing. Overexpression of Heat4 in monocytes decreased levels of pro-inflammatory cytokines such as TNFα (38.6% reduction, p&lt;0.05). Conversely, the knockdown of Heat4 resulted in elevated levels of pro-inflammatory cytokines, including IL6 (10.83-fold, p&lt;0.05) and TNFα (4.14-fold, p&lt;0.05). In a larger cohort including patients with HF, Heat4 was able to determine the prevalence of heart failure by AUC=0.734 (p&lt;0.05). Moreover, in a 4-year follow-up of the same cohort, Heat4 predicted mortality by AUC=0.789 (HF: N=63, Dead=32; Controls: N=38, Dead=0; p&lt;0.05).

Conclusion

The long non-coding RNA Heat4 is elevated in the blood of HF patients. Mechanistically, Heat4 limits the extent of the inflammatory response of non-classical monocytes. Therefore, Heat4 may provide a regulatory link between inflammation and HF.

Funding Acknowledgement

Type of funding sources: None.

Reduced RNA editing in the failing human heart mediates alternative circular RNA splicing

Background and purpose

Post-transcriptional RNA editing is an important mechanism in the development of human diseases. RNA editing can affect RNA stability and alternative splicing. The aim of our study was to characterize RNA editing and its impact on alternative RNA splicing in the healthy and failing human heart.

Methods and results

Human heart samples of heart failure (HF) patients (n=20) and controls (n=10) were analyzed using RNA sequencing with subsequent analysis of RNA editing. We identified adenosine-to-inosine (A-to-I) editing as the major form of RNA editing in human hearts, being reduced in HF patients. Consistently, we found the editing enzyme ADAR2 reduced in HF patients. A-to-I RNA editing predominantly occurred in intronic regions of protein-coding genes, specifically in repetitive, primate-specific Alu elements which can affect RNA splicing. Indeed, we found 173 circular RNAs (circRNAs) regulated by alternative mRNA splicing in the failing heart.

Loss of ADAR2 led to reduced RNA editing concomitant with an increase of circRNA, while overexpression reduced circRNA expression and enhanced RNA editing.

Conclusion

A-to-I editing is the major type of RNA editing in the human heart, being reduced in HF. We demonstrate a primate-specific alternative RNA splicing mechanism mediated by RNA editing in human hearts. The findings may be relevant to diseases with reduced RNA editing such as cancer, neurological and cardiac diseases.

Funding Acknowledgement

Type of funding sources: None.

P–355 Cancer diagnosis among patients with recurrent pregnancy loss: a cohort study

Study question

Is unexplained recurrent pregnancy loss (RPL) related to long term cancer morbidity?

Summary answer

Recurrent unexplained pregnancy loss patients showed lower cancer morbidity. This trend was significant in the secondary aborters and in a sub-analysis for gynecological cancers.

What is known already

The association between infertility and cancer was studied, but has scarcely been studied in RPL; One study reported a higher incidence of breast and uterine cancers, while another found no association. Immune dysfunction is a possible cause of ‘unexplained RPL’; RPL patients have an increased number of toxic natural killer cells (NKs) in both peripheral blood and decidua. The immune system is also involved in the recognition of cancer cells, potentially leading to effective killing. It is possible that the NK populations in RPL are capable of a better response towards cancer cells in the uterine environment and related organs.

Study design, size, duration

A retrospective cohort study comparing RPL patients and patients with normal deliveries presenting between 1990 –2010 and followed up until 2018.

Participants/materials, setting, methods

The RPL (exposed) group consisted of patients with 3 or more losses between 5–24 weeks. The comparison (unexposed) group included women who gave birth, and were not listed in the registry of RPL patients. Matching was based on maternal age and year of delivery, which was matched to the date of admission to the RPL clinic. Patients’ data were cross-linked to the national cancer registry. Kaplan-Meier survival curves were used to compare cancer incidence.

Main results and the role of chance

The RPL group comprised of 937 RPL patients, compared to 4685 patients with a live birth. The mean follow up time was 16.3 ±5.3 years for RPL cases and 15.9 ± 4.9 for the comparison group. Groups were compared in terms of lifetime risk, post-admission risk and according to cancer type. In a Univariate analysis, the life time risk for cancer was 5.3% (49/937) among RPL patients and 6.8% (317/4685) in the comparison group (p = 0.08). Survival analysis showed the same trend - a lower cancer morbidity in RPL patients (p = 0.06). The low cancer morbidity was more prominent, reaching statistical significance in secondary RPL patients (p = 0.05) , but not in primary RPL (p = 0.4). Breast cancer was the most common tumor, but was neither more nor less common in RPL than in the comparison group. Gynecological cancers, however, were significantly less common in RPL patients: 0.3% (3/937) compared to 1.3% (60/4685) in the comparison group (p = 0.01). After adjustment for maternal age the odds ratio for gynecological cancer was 0.247 (p = 0.018, 95% CI 0.077–0.791) and significantly represented in the survival analysis (p = 0.01).

Limitations, reasons for caution

There was no access to BMI and smoking status. Patients were followed for a mean period of 16 years; cancer may present later than 16 years.

Wider implications of the findings: Unexplained RPL is assumed to have an immunological basis. Our study may provide an indirect support for hyper-responsive immunological mechanisms in RPL patients. Further research is needed to deepen our understanding of the underlying mechanisms and possibly to facilitate treatment options.

Trial registration number

Not applicable

Extracellular NLRP3 inflammasome particles are internalized by human coronary artery smooth muscle cells and induce pro-atherogenic effects

Inflammation driven by intracellular activation of the NLRP3 inflammasome is involved in the pathogenesis of a variety of diseases including vascular pathologies. Inflammasome specks are released into the extracellular compartment from disrupting pyroptotic cells. The potential uptake and function of extracellular NLRP3 inflammasomes in human coronary artery smooth muscle cells (HCASMC) are unknown. Fluorescently labeled NLRP3 inflammasome particles were isolated from a mutant NLRP3-YFP cell line and used to treat primary HCASMC for 4 and 24 h. Fluorescent and expressional analyses showed that extracellular NLRP3-YFP particles are internalized into HCASMC, where they remain active and stimulate intracellular caspase-1 (1.9-fold) and IL-1β (1.5-fold) activation without inducing pyroptotic cell death. Transcriptomic analysis revealed increased expression level of pro-inflammatory adhesion molecules (ICAM1, CADM1), NLRP3 and genes involved in cytoskleleton organization. The NLRP3-YFP particle-induced gene expression was not dependent on NLRP3 and caspase-1 activation. Instead, the effects were partly abrogated by blocking NFκB activation. Genes, upregulated by extracellular NLRP3 were validated in human carotid artery atheromatous plaques. Extracellular NLRP3-YFP inflammasome particles promoted the secretion of pro-atherogenic and inflammatory cytokines such as CCL2/MCP1, CXCL1 and IL-17E, and increased HCASMC migration (1.8-fold) and extracellular matrix production, such as fibronectin (5.8-fold) which was dependent on NFκB and NLRP3 activation. Extracellular NLRP3 inflammasome particles are internalized into human coronary artery smooth muscle cells where they induce pro-inflammatory and pro-atherogenic effects representing a novel mechanism of cell-cell communication and perpetuation of inflammation in atherosclerosis. Therefore, extracellular NLRP3 inflammasomes may be useful to improve the diagnosis of inflammatory diseases and the development of novel anti-inflammatory therapeutic strategies.

SLM2 Is A Novel Cardiac Splicing Factor Involved in Heart Failure due to Dilated Cardiomyopathy

Alternative mRNA splicing is a fundamental process to increase the versatility of the genome. In humans, cardiac mRNA splicing is involved in the pathophysiology of heart failure. Mutations in the splicing factor RNA binding motif protein 20 (RBM20) cause severe forms of cardiomyopathy. To identify novel cardiomyopathy-associated splicing factors, RNA-seq and tissue-enrichment analyses were performed, which identified up-regulated expression of Sam68-Like mammalian protein 2 (SLM2) in the left ventricle of dilated cardiomyopathy (DCM) patients. In the human heart, SLM2 binds to important transcripts of sarcomere constituents, such as those encoding myosin light chain 2 (MYL2), troponin I3 (TNNI3), troponin T2 (TNNT2), tropomyosin 1/2 (TPM1/2), and titin (TTN). Mechanistically, SLM2 mediates intron retention, prevents exon exclusion, and thereby mediates alternative splicing of the mRNA regions encoding the variable proline-, glutamate-, valine-, and lysine-rich (PEVK) domain and another part of the I-band region of titin. In summary, SLM2 is a novel cardiac splicing regulator with essential functions for maintaining cardiomyocyte integrity by binding to and processing the mRNAs of essential cardiac constituents such as titin.

A novel risk model for predicting potentially life-threatening arrhythmias in non-ischemic dilated cardiomyopathy (DCM-SVA risk)

BACKGROUND

Non-ischemic dilated cardiomyopathy (DCM) can be complicated by sustained ventricular arrhythmias (SVA) and sudden cardiac death (SCD). By now, left-ventricular ejection fraction (LV-EF) is the main guideline criterion for primary prophylactic ICD implantation, potentially leading either to overtreatment or failed detection of patients at risk without severely impaired LV-EF. The aim of the European multi-center study DETECTIN-HF was to establish a clinical risk calculator for individualized risk stratification of DCM patients.

METHODS

1393 patients (68% male, mean age 50.7 ± 14.3y) from four European countries were included. The outcome was occurrence of first potentially life-threatening ventricular arrhythmia. The model was developed using Cox proportional hazards, and internally validated using cross validation. The model included seven independent and easily accessible clinical parameters sex, history of non-sustained ventricular tachycardia, history of syncope, family history of cardiomyopathy, QRS duration, LV-EF, and history of atrial fibrillation. The model was also expanded to account for presence of LGE as the eight8h parameter for cases with available cMRI and scar information.

RESULTS

During a mean follow-up period of 57.0 months, 193 (13.8%) patients experienced an arrhythmic event. The calibration slope of the developed model was 00.97 (95% CI 0.90-1.03) and the C-index was 0.72 (95% CI 0.71-0.73). Compared to current guidelines, the model was able to protect the same number of patients (5-year risk ≥8.5%) with 15% fewer ICD implantations.

CONCLUSIONS

This DCM-SVA risk model could improve decision making in primary prevention of SCD in non-ischemic DCM using easily accessible clinical information and will likely reduce overtreatment.

LDL cholesterol level as a risk factor for retinopathy and nephropathy in children and adults with type 1 diabetes mellitus: A nationwide cohort study

BACKGROUND

Microvascular complications are common in people with diabetes, where poor glycaemic control is the major contributor. The aim of this study was to explore the association between elevated LDL cholesterol levels and the risk of retinopathy or nephropathy in young individuals with type 1 diabetes.

METHODS

This was a nationwide observational population-based cohort study, including all children and adults with a duration of type 1 diabetes of ≤ 10 years, identified in the Swedish National Diabetes Register between 1998 and 2017. We calculated the crude incidence rates with 95% confidence intervals (CIs) and used multivariable Cox regression to estimate crude and adjusted hazard ratios (HRs) of retinopathy or nephropathy in four LDL cholesterol categories: <2.6 (Reference), 2.6-3.4, 3.4-4.1 and > 4.1 mmol L^-1 .

RESULTS

In total, 11 024/12 350 (retinopathy/nephropathy, both cohorts, respectively) children and adults (median age 21 years, female 42%) were followed up to 28 years from diagnosis until end of study. Median duration of diabetes when entering the study was 6 and 7 years in the retinopathy and nephropathy cohort, respectively. Median LDL cholesterol was 2.4 mmol L^-1 , and median HbA1c level was 61 mmol mol^-1 (7.7 %). After multivariable adjustment, the HRs (95% CI) for retinopathy in individuals with LDL cholesterol levels of 2.6-3.4, 3.4-4.1 or > 4.1 mmol L^-1 were as follows: 1.13 (1.03-1.23), 1.16 (1.02-1.32) and 1.18 (0.99-1.41), compared with the reference. The corresponding numbers for nephropathy were as follows: 1.15 (0.96-1.32), 1.30 (1.03-1.65) and 1.41 (1.06-1.89).

CONCLUSIONS

Young individuals with type 1 diabetes exposed to high LDL cholesterol levels have an increased risk of retinopathy and nephropathy independent of glycaemia and other identified risk factors for vascular complications.

Genome-wide association analysis in dilated cardiomyopathy reveals two new players in systolic heart failure on chromosomes 3p25.1 and 22q11.23

AIMS

Our objective was to better understand the genetic bases of dilated cardiomyopathy (DCM), a leading cause of systolic heart failure.

METHODS AND RESULTS

We conducted the largest genome-wide association study performed so far in DCM, with 2719 cases and 4440 controls in the discovery population. We identified and replicated two new DCM-associated loci on chromosome 3p25.1 [lead single-nucleotide polymorphism (SNP) rs62232870, P = 8.7 × 10-11 and 7.7 × 10-4 in the discovery and replication steps, respectively] and chromosome 22q11.23 (lead SNP rs7284877, P = 3.3 × 10-8 and 1.4 × 10-3 in the discovery and replication steps, respectively), while confirming two previously identified DCM loci on chromosomes 10 and 1, BAG3 and HSPB7. A genetic risk score constructed from the number of risk alleles at these four DCM loci revealed a 3-fold increased risk of DCM for individuals with 8 risk alleles compared to individuals with 5 risk alleles (median of the referral population). In silico annotation and functional 4C-sequencing analyses on iPSC-derived cardiomyocytes identify SLC6A6 as the most likely DCM gene at the 3p25.1 locus. This gene encodes a taurine transporter whose involvement in myocardial dysfunction and DCM is supported by numerous observations in humans and animals. At the 22q11.23 locus, in silico and data mining annotations, and to a lesser extent functional analysis, strongly suggest SMARCB1 as the candidate culprit gene.

CONCLUSION

This study provides a better understanding of the genetic architecture of DCM and sheds light on novel biological pathways underlying heart failure.

Association between travel time to delivery unit and unplanned out-of-hospital birth, infant morbidity and mortality: A population-based cohort study

INTRODUCTION

Over the last decade, a number of delivery units have been closed in Sweden, justified by both economic incentives and patient safety issues. However, concentrating births to larger delivery units naturally increases travel time for some parturient women, which may lead to unintended negative consequences. We aimed to investigate the association between travel time to delivery unit and unplanned out-of-hospital birth, and subsequent infant morbidity and mortality.

MATERIAL AND METHODS

We performed a population-based cohort study including 365 604 women in the Swedish Pregnancy Register, giving birth between 2014 and 2017. Modified Poisson regression was used to investigate the association between travel time from home address to actual delivery unit, based on geographic information system analysis, and risk of an unplanned out-of-hospital birth. Analyses were stratified by parity and urban/rural residence. Lastly, the associations between an unplanned out-of-hospital birth and severe infant morbidity, stillbirth, peripartum, perinatal and neonatal mortality were investigated.

RESULTS

Of those with an unplanned out-of-hospital birth (n = 2159), 65% had a travel time up to 30 minutes. A travel time between 31 and 60 minutes was associated with a doubled risk of unplanned out-of-hospital birth (adjusted risk ratio [RR] 1.96, 95% confidence interval [CI] 1.74-2.22) and women with a travel time of more than 1 hour had an adjusted RR of 3.19 (95% CI 2.64-3.86), compared with those with a travel time of <30 minutes. No difference in results was seen when stratified for parity and urban/rural residence. No association was found between unplanned out-of-hospital birth and severe infant morbidity. Significant associations were found in crude analyses for stillbirth (RR 1.85, 95% CI 1.09-3.13), peripartum (RR 1.93, 95% CI 1.18-3.16), perinatal (RR 2.03, 95% CI 1.28-3.23) and neonatal mortality (RR 3.08, 95% CI 1.27-7.46), although neonatal mortality was very rare (2.3/1000 out-of-hospital births). Similar effect estimates were found in the adjusted analyses, though no longer significant.

CONCLUSIONS

Although the majority of unplanned out-of-hospital births occurred in the group of women with a travel time of 0-30 minutes, increasing travel time to a delivery unit is associated with unplanned out-of-hospital birth, which may increase the risk of mortality.

GnRH agonist and hCG (dual trigger) versus hCG trigger for final follicular maturation: a double-blinded, randomized controlled study

STUDY QUESTION

Does co-administration of GnRH agonist and Human chorionic gonadotropin (hCG; dual trigger) in IVF cycles improve the number of mature oocytes and pregnancy outcome compared to hCG alone?

SUMMARY ANSWER

Using the dual trigger for final follicular maturation increases the number of oocytes, mature oocytes and number of blastocysts (total and top-quality) compared to triggering with hCG alone.

WHAT IS KNOWN ALREADY

hCG is used at the end of controlled ovarian hyperstimulation as a surrogate LH surge to induce final oocyte maturation. Recently, based on retrospective studies, the co-administration of GnRH agonist and hCG for final oocyte maturation (dual trigger) has been suggested to improve IVF outcome and pregnancy rates.

STUDY DESIGN, SIZE, DURATION

A single center, randomized controlled, double-blinded clinical trial between May 2016 and June 2018 analyzed by intention to treat (ITT).

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

One hundred and fifty-five normal responder patients were randomized either to receive hCG or dual trigger for final oocyte maturation. Data on patients age, BMI, AMH, number of oocytes retrieved, number of metaphase 2 (MII) oocytes, zygotes and blastocysts, clinical pregnancy rate and live birth rate were assessed and compared between the dual trigger group and the hCG group. We performed a planned interim analysis after the recruitment of 50% of the patients. Based on the totality of outcomes at the interim analysis we decided to discontinue further recruitment.

MAIN RESULTS AND THE ROLE OF CHANCE

One hundred and fifty-five patients were included in the study. The age (36 years versus 35.3 years P = NS), BMI (24 kg/m2 versus 23.7 kg/m2) and the AMH (20.1 pmol/l versus 22.4 pmol/l) were comparable between the two groups. Based on ITT analysis, the number of eggs retrieved (11.1 versus 13.4, P = 0.002), the MII oocytes (8.6 versus 10.3, P = 0.009), total number of blastocysts (2.9 versus 3.9, P = 0.01) and top-quality blastocysts transferred (44.7% versus 64.9%; P = 0.003) were significantly higher in the dual trigger group compared to the hCG group. The clinical pregnancy rate (24.3% versus 46.1%, OR 2.65 (1.43-1.93), P = 0.009) and the live birth rate per transfer (22% versus 36.2%, OR= 1.98 (1.05-3.75), P = 0.03) were significantly higher in the dual trigger group compared to the hCG group.

LIMITATIONS, REASONS FOR CAUTION

None.

WIDER IMPLICATIONS OF THE FINDINGS

The enhanced response observed with the dual trigger might lead to better IVF outcomes were it used more widely.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by TRIO Fertility. There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier: NCT02703584.

DATE OF TRIAL REGISTRATION

March 2016.

DATE OF FIRST PATIENT'S ENROLLMENT

May 2016.

Parvovirus B19 and mumps virus antibodies are major constituents of the intrathecal immune response in European patients with MS and increase the diagnostic sensitivity and discriminatory power of the MRZ reaction

Background

A positive MRZ reaction, as defined by intrathecal IgG production against at least two of its constituents, measles virus (M), rubella virus (R) and varicella zoster virus (Z), is detectable in ~ 63% of patients with multiple sclerosis (MS) and is currently considered the laboratory marker with the highest specificity and positive likelihood ratio for MS. However, M, R and Z are only the most well-established constituents of a broader intrathecal humoral immune response in MS.

Objective

To identify additional anti-microbial antibodies inclusion of which in the classical MRZ panel may result in increased sensitivity without compromising the marker’s high specificity for MS.

Methods

We determined the antibody indices (AIs) for 11 viral and bacterial agents (M, R, Z, herpes simplex virus, Epstein–Barr virus, mumps virus, cytomegalovirus, parvovirus B19, Bordetella pertussis, Corynebacterium diphtheriae, and Clostridium tetani) in paired cerebrospinal fluid and serum samples from patients with MS and disease controls.

Results

A positive ‘classical’ MRZ reaction was found in 17/26 (65.4%) MS patients. The five most frequently positive AIs among patients with MS were M (76.9%), Z (61.5%), R (57.7%), parvovirus B19 (42.3%), and mumps (28%). Addition of parvovirus B19 and mumps virus to the MRZ panel resulted in an increase in sensitivity in the MS group from 65.4% to 73.1%, with 22% of the initially MRZ-negative patients exhibiting a de novo-positive response. The extended MRZ panel (‘MRZplus’) distinguished sharply between MS (≥ 3 AIs in 90% of all positives) and controls (varying diagnoses, from migraine to vasculitis; 0-1 AIs; p < 0.000001). The highest median AI in the MS group was found for parvovirus B19 (3.97), followed by measles virus (2.79).

Conclusion

Inclusion of parvovirus B19 and mumps virus in the test panel resulted in an increase in the sensitivity and discriminatory power of MRZ. Our results provide a strong rational for prospective studies investigating the role of extended MRZ panels in the differential diagnosis of MS.

Energy Metabolites as Biomarkers in Ischemic and Dilated Cardiomyopathy

With more than 25 million people affected, heart failure (HF) is a global threat. As energy production pathways are known to play a pivotal role in HF, we sought here to identify key metabolic changes in ischemic- and non-ischemic HF by using a multi-OMICS approach. Serum metabolites and mRNAseq and epigenetic DNA methylation profiles were analyzed from blood and left ventricular heart biopsy specimens of the same individuals. In total we collected serum from n = 82 patients with Dilated Cardiomyopathy (DCM) and n = 51 controls in the screening stage. We identified several metabolites involved in glycolysis and citric acid cycle to be elevated up to 5.7-fold in DCM (p = 1.7 × 10⁻⁶). Interestingly, cardiac mRNA and epigenetic changes of genes encoding rate-limiting enzymes of these pathways could also be found and validated in our second stage of metabolite assessment in n = 52 DCM, n = 39 ischemic HF and n = 57 controls. In conclusion, we identified a new set of metabolomic biomarkers for HF. We were able to identify underlying biological cascades that potentially represent suitable intervention targets.

Necrotizing enterocolitis and its association with the neonatal abstinence syndrome

OBJECTIVE:

The purpose of this study was to describe an identified association between necrotizing enterocolitis (NEC) and prenatal opioid exposure with neonatal abstinence syndrome (NAS) in late preterm and full-term neonates.

STUDY DESIGN:

In this single-center retrospective cohort study, we analyzed inborn neonates with the diagnosis of NEC discharged from 2012 through 2017. We compared infants with NEC > 35 weeks’ gestation to those with NEC<35 weeks’ gestation. We compared gestational age, birth weight, age of onset of symptoms, and incidence of prenatal drug exposure between groups. Significance was determined using Mann-Whitney and Fisher’s exact tests.

RESULTS:

Over the study period, 23 infants were identified with NEC, 9 (39%) were babies > 35 weeks at birth and 14 (61%) < 35 weeks. Those > 35 weeks had a higher birth weight, earlier onset of symptoms, and a higher percentage of prenatal exposure to opioids compared to those < 35 weeks’ gestation. We further described seven infants with late gestational age onset NEC associated with prenatal opioid exposure.

CONCLUSIONS:

In this cohort of infants with NEC discharged over a 6 year period we found a higher than expected percentage of infants born at a later gestational age. We speculate that prenatal opioid exposure might be a risk factor for NEC in neonates born at > 35 weeks.

Optimal timing of fetal reduction from twins to singleton: earlier the better or later the better?

OBJECTIVES

To determine the rate of pregnancy complications and adverse obstetric and neonatal outcomes of twin pregnancies that were reduced to singleton at an early compared with a later gestational age.

METHODS

This was a historical cohort study of dichorionic diamniotic twin pregnancies that underwent fetal reduction to singletons in a single tertiary referral center between January 2005 and February 2017. The study population was divided into two groups according to gestational age at fetal reduction: those performed at 11-14 weeks' gestation, mainly at the patient's request or as a result of a complicated medical or obstetric history; and selective reductions performed at 15-23 weeks for structural or genetic anomalies. The main outcome measures compared between pregnancies that underwent early reduction and those that underwent late reduction included rates of pregnancy complications, pregnancy loss, preterm delivery and adverse neonatal outcome.

RESULTS

In total, 248 dichorionic diamniotic twin pregnancies were included, of which 172 underwent early reduction and 76 underwent late reduction. Although gestational age at delivery was not significantly different between the late- and early-reduction groups (38 weeks, (interquartile range (IQR), 36-40 weeks) vs 39 weeks (IQR, 38-40 weeks); P = 0.2), the rates of preterm delivery < 37 weeks (28.0% vs 14.0%; P = 0.01), < 34 weeks (12.0% vs 1.8%; P = 0.002) and < 32 weeks (8.0% vs 1.8%; P = 0.026) were significantly higher in pregnancies that underwent late reduction. Regression analysis revealed that late reduction of twins was an independent risk factor for preterm delivery, after adjustment for maternal age, parity, body mass index and the location of the reduced sac. Rates of early complications linked to the reduction procedure itself, such as infection, vaginal bleeding and leakage of fluids, were comparable between the groups (7.0% for early reduction vs 9.2% for late reduction; P = 0.53). There was no significant difference in the rate of pregnancy loss before 24 weeks (0.6% for early reduction vs 1.3% for late reduction; P = 0.52), and no cases of intrauterine fetal death at or after 24 weeks were documented. There was no significant difference in the prevalence of gestational diabetes mellitus, hypertensive disorders of pregnancy, preterm prelabor rupture of membranes or small-for-gestational age. The rates of respiratory distress syndrome (6.7% vs 0%; P = 0.002), need for mechanical ventilation (6.7% vs 0.6%; P = 0.01) and composite neonatal morbidity (defined as one or more of respiratory distress syndrome, sepsis, necrotizing enterocolitis, intraventricular hemorrhage, need for respiratory support or neonatal death) (10.7% vs 2.9%; P = 0.025) were higher in the late- than in the early-reduction group. Other neonatal outcomes were comparable between the groups.

CONCLUSIONS

Compared with late first-trimester reduction of twins, second-trimester reduction is associated with an increased rate of prematurity and adverse neonatal outcome, without increasing the rate of procedure-related complications. Technological advances in sonographic diagnosis and more frequent use of chorionic villus sampling have enabled earlier detection of fetal anatomic and chromosomal abnormalities. Therefore, efforts should be made to complete early fetal assessment to allow reduction during the first trimester. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Degeneration alters the biomechanical properties and structural composition of lateral human menisci

OBJECTIVE

Because the literature relating to the influence of degeneration on the viscoelasticity and tissue composition of human lateral menisci remains contradictory or completely lacking, the aim of this study was to fill these gaps by comprehensively characterising the biomechanical properties of menisci with regard to the degree of degeneration.

DESIGN

Meniscal tissue from 24 patients undergoing a total knee replacement was collected and the degeneration of each region classified according to Pauli et al. For biomechanical characterisation, compression and tensile tests were performed. Additionally, the water content was determined and infrared (IR) spectroscopy was applied to detect changes in the structural composition, particularly of the proteoglycan and collagen content.

RESULTS

With an increasing degree of degeneration, a significant decrease of the equilibrium modulus was detected, while simultaneously the water content and the hydraulic permeability significantly increased. However, the tensile modulus displayed a tendency to decrease with increasing degeneration, which might be due to the significantly decreasing amount of collagen content identified by the IR measurements.

CONCLUSION

The findings of the current study may contribute to the understanding of meniscus degeneration, showing that degenerative processes appear to mainly worsen viscoelastic properties of the inner circumference by disrupting the collagen integrity.

Dual Functional States of R406W-Desmin Assembly Complexes Cause Cardiomyopathy With Severe Intercalated Disc Derangement in Humans and in Knock-In Mice

BACKGROUND

Mutations in the human desmin gene cause myopathies and cardiomyopathies. This study aimed to elucidate molecular mechanisms initiated by the heterozygous R406W-desmin mutation in the development of a severe and early-onset cardiac phenotype.

METHODS

We report an adolescent patient who underwent cardiac transplantation as a result of restrictive cardiomyopathy caused by a heterozygous R406W-desmin mutation. Sections of the explanted heart were analyzed with antibodies specific to 406W-desmin and to intercalated disc proteins. Effects of the R406W mutation on the molecular properties of desmin were addressed by cell transfection and in vitro assembly experiments. To prove the genuine deleterious effect of the mutation on heart tissue, we further generated and analyzed R405W-desmin knock-in mice harboring the orthologous form of the human R406W-desmin.

RESULTS

Microscopic analysis of the explanted heart revealed desmin aggregates and the absence of desmin filaments at intercalated discs. Structural changes within intercalated discs were revealed by the abnormal organization of desmoplakin, plectin, N-cadherin, and connexin-43. Next-generation sequencing confirmed the DES variant c.1216C>T (p.R406W) as the sole disease-causing mutation. Cell transfection studies disclosed a dual behavior of R406W-desmin with both its integration into the endogenous intermediate filament system and segregation into protein aggregates. In vitro, R406W-desmin formed unusually thick filaments that organized into complex filament aggregates and fibrillar sheets. In contrast, assembly of equimolar mixtures of mutant and wild-type desmin generated chimeric filaments of seemingly normal morphology but with occasional prominent irregularities. Heterozygous and homozygous R405W-desmin knock-in mice develop both a myopathy and a cardiomyopathy. In particular, the main histopathologic results from the patient are recapitulated in the hearts from R405W-desmin knock-in mice of both genotypes. Moreover, whereas heterozygous knock-in mice have a normal life span, homozygous animals die at 3 months of age because of a smooth muscle-related gastrointestinal phenotype.

CONCLUSIONS

We demonstrate that R406W-desmin provokes its severe cardiotoxic potential by a novel pathomechanism, where the concurrent dual functional states of mutant desmin assembly complexes underlie the uncoupling of desmin filaments from intercalated discs and their structural disorganization.

Clinical and Genetic Investigations of 109 Index Patients With Dilated Cardiomyopathy and 445 of Their Relatives

BACKGROUND

It was the aim to investigate the frequency and genetic basis of dilated cardiomyopathy (DCM) among relatives of index patients with unexplained heart failure at a tertiary referral center.

METHODS

Clinical investigations were performed in 109 DCM index patients and 445 of their relatives. All index patients underwent genetic investigations of 76 disease-associated DCM genes. A family history of DCM occurred in 11% (n=12) while clinical investigations identified familial DCM in a total of 32% (n=35). One-fifth of all relatives (n=95) had DCM of whom 60% (n=57) had symptoms of heart failure at diagnosis, whereas 40% (n=38) were asymptomatic. Symptomatic relatives had a shorter event-free survival than asymptomatic DCM relatives (P<0.001).

RESULTS

Genetic investigations identified 43 pathogenic (n=27) or likely pathogenic (n=16) variants according to the American College of Medical Genetics and Genomics and the Association for Molecular Pathology criteria. Forty-four percent (n=48/109) of index patients carried a pathogenic/likely pathogenic variant of whom 36% (n=27/74) had sporadic DCM, whereas 60% (21/35) were familial cases. Thirteen of the pathogenic/likely pathogenic variants were also present in ≥7 affected individuals and thereby considered to be of sufficient high confidence for use in predictive genetic testing.

CONCLUSIONS

A family history of DCM identified only 34% (n=12/35) of hereditary DCM, whereas systematic clinical screening identified the remaining 66% (n=23) of DCM families. This emphasized the importance of clinical investigations to identify familial DCM. The high number of pathogenic/likely pathogenic variants identified in familial DCM provides a firm basis for offering genetic investigations in affected families. This should also be considered in sporadic cases since adequate family evaluation may not always be possible and the results of the genetic investigations may carry prognostic information with an impact on individual management.

Long noncoding RNA NEAT1 modulates immune cell functions and is suppressed in early onset myocardial infarction patients

AIMS

Inflammation is a key driver of atherosclerosis and myocardial infarction (MI), and beyond proteins and microRNAs (miRs), long noncoding RNAs (lncRNAs) have been implicated in inflammation control. To obtain further information on the possible role of lncRNAs in the context of atherosclerosis, we obtained comprehensive transcriptome maps of circulating immune cells (peripheral blood mononuclear cells, PBMCs) of early onset MI patients. One lncRNA significantly suppressed in post-MI patients was further investigated in a murine knockout model.

METHODS AND RESULTS

Individual RNA-sequencing (RNA-seq) was conducted on PBMCs from 28 post-MI patients with a history of MI at age ≤50 years and stable disease ≥3 months before study participation, and from 31 healthy individuals without manifest cardiovascular disease or family history of MI as controls. RNA-seq revealed deregulated protein-coding transcripts and lncRNAs in post-MI PBMCs, among which nuclear enriched abundant transcript (NEAT1) was the most highly expressed lncRNA, and the only one significantly suppressed in patients. Multivariate statistical analysis of validation cohorts of 106 post-MI patients and 85 controls indicated that the PBMC NEAT1 levels were influenced (P = 0.001) by post-MI status independent of statin intake, left ventricular ejection fraction, low-density lipoprotein or high-density lipoprotein cholesterol, or age. We investigated NEAT1-/- mice as a model of NEAT1 deficiency to evaluate if NEAT1 depletion may directly and causally alter immune regulation. RNA-seq of NEAT1-/- splenocytes identified disturbed expression and regulation of chemokines/receptors, innate immunity genes, tumour necrosis factor (TNF) and caspases, and increased production of reactive oxygen species (ROS) under baseline conditions. NEAT1-/- spleen displayed anomalous Treg and TH cell differentiation. NEAT1-/- bone marrow-derived macrophages (BMDMs) displayed altered transcriptomes with disturbed chemokine/chemokine receptor expression, increased baseline phagocytosis (P < 0.0001), and attenuated proliferation (P = 0.0013). NEAT1-/- BMDMs responded to LPS with increased (P < 0.0001) ROS production and disturbed phagocytic activity (P = 0.0318). Monocyte-macrophage differentiation was deregulated in NEAT1-/- bone marrow and blood. NEAT1-/- mice displayed aortic wall CD68+ cell infiltration, and there was evidence of myocardial inflammation which could lead to severe and potentially life-threatening structural damage in some of these animals.

CONCLUSION

The study indicates distinctive alterations of lncRNA expression in post-MI patient PBMCs. Regarding the monocyte-enriched NEAT1 suppressed in post-MI patients, the data from NEAT1-/- mice identify NEAT1 as a novel lncRNA-type immunoregulator affecting monocyte-macrophage functions and T cell differentiation. NEAT1 is part of a molecular circuit also involving several chemokines and interleukins persistently deregulated post-MI. Individual profiling of this circuit may contribute to identify high-risk patients likely to benefit from immunomodulatory therapies. It also appears reasonable to look for new therapeutic targets within this circuit.

Epigenetic Regulation of Alternative mRNA Splicing in Dilated Cardiomyopathy

In recent years, the genetic architecture of dilated cardiomyopathy (DCM) has been more thoroughly elucidated. However, there is still insufficient knowledge on the modifiers and regulatory principles that lead to the failure of myocardial function. The current study investigates the association of epigenome-wide DNA methylation and alternative splicing, both of which are important regulatory principles in DCM. We analyzed screening and replication cohorts of cases and controls and identified distinct transcriptomic patterns in the myocardium that differ significantly, and we identified a strong association of intronic DNA methylation and flanking exons usage (p < 2 × 10^-16). By combining differential exon usage (DEU) and differential methylation regions (DMR), we found a significant change of regulation in important sarcomeric and other DCM-associated pathways. Interestingly, inverse regulation of Titin antisense non-coding RNA transcript splicing and DNA methylation of a locus reciprocal to TTN substantiate these findings and indicate an additional role for non-protein-coding transcripts. In summary, this study highlights for the first time the close interrelationship between genetic imprinting by DNA methylation and the transport of this epigenetic information towards the dynamic mRNA splicing landscape. This expands our knowledge of the genome-environment interaction in DCM besides simple gene expression regulation.

Familial Recurrent Myocarditis Triggered by Exercise in Patients With a Truncating Variant of the Desmoplakin Gene

Background

Variants of the desmosomal protein desmoplakin are associated with arrhythmogenic cardiomyopathy, an important cause of ventricular arrhythmias in children and young adults. Disease penetrance of desmoplakin variants is incomplete and variant carriers may display noncardiac, dermatologic phenotypes. We describe a novel cardiac phenotype associated with a truncating desmoplakin variant, likely causing mechanical instability of myocardial desmosomes.

Methods and Results

In 2 young brothers with recurrent myocarditis triggered by physical exercise, screening of 218 cardiomyopathy‐related genes identified the heterozygous truncating variant p.Arg1458Ter in desmoplakin. Screening for infections yielded no evidence of viral or nonviral infections. Myosin and troponin I autoantibodies were detected at high titers. Immunohistology failed to detect any residual DSP protein in endomyocardial biopsies, and none of the histologic criteria of arrhythmogenic cardiomyopathy were fulfilled. Cardiac magnetic resonance imaging revealed no features associated with right ventricular arrhythmogenic cardiomyopathy, but multifocal subepicardial late gadolinium enhancement was present in the left ventricles of both brothers. Screening of adult cardiomyopathy cohorts for truncating variants identified the rare genetic variants p.Gln307Ter, p.Tyr1391Ter, and p.Tyr1512Ter, suggesting that over subsequent decades critical genetic/exogenous modifiers drive pathogenesis from desmoplakin truncations toward different end points.

Conclusions

The described novel phenotype of familial recurrent myocarditis associated with a desmoplakin truncation in adolescents likely represents a serendipitously revealed subtype of arrhythmogenic cardiomyopathy. It may be caused by a distinctive adverse effect of the variant desmoplakin upon the mechanical stability of myocardial desmosomes. Variant screening is advisable to allow early detection of patients with similar phenotypes.

Immune system-mediated atherosclerosis caused by deficiency of long non-coding RNA MALAT1 in ApoE-/-mice

Aims

The immune system is considered a key driver of atherosclerosis, and beyond proteins and microRNAs (miRs), long non-coding RNAs (lncRNAs) are implicated in immune control. We previously described that lncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is involved in cardiac innate immunity in a myocarditis model. Here, we investigated the impact of MALAT1 deficiency upon atherosclerosis development.

Methods and results

Heterozygous MALAT1-deficient ApoE-/- mice displayed massive immune system dysregulation and atherosclerosis within 2 months even when kept on normal diet. Aortic plaque area (P < 0.05) and aortic root plaque size (P < 0.001) were increased in MALAT1-deficient vs. MALAT1-wildtype ApoE-/- mice. Serum levels of interferon-γ (IFN-γ), tumour necrosis factor (TNF), and interleukin 6 (IL6) were elevated (P < 0.001) in MALAT1-deficient animals. MALAT1-deficient bone marrow-derived macrophages showed enhanced expression of TNF (P = 0.001) and inducible NO synthase (NOS2) (P = 0.002), suppressed MMP9 (P < 0.001), and impaired phagocytic activity (P < 0.001) upon lipopolysaccharide stimulation. RNA-sequencing revealed grossly altered transcriptomes of MALAT1-deficient splenocytes already at baseline, with massive induction of IFN- γ, TNF, NOS2, and granzyme B; CC and CXC chemokines and CCR8; and innate immunity genes interferon-induced protein with tetratricopeptide repeats (IFIT)1/3, interferon-induced transmembrane protein (IFITM)1/3, ISG15. Multiple miRs were up to 45-fold upregulated. Further, selective ablation of the cytosolic part of the MALAT1 system only, the enzymatically MALAT1-derived mascRNA, resulted in massive induction of TNF (P = 0.004) and IL6 (P = 0.028) in macrophages. Northern analysis of post-myocardial infarction patient vs. control peripheral blood mononuclear cells showed reduced (P = 0.005) mascRNA in the patients. CHART-enriched RNA-sequencing reads at the genomic loci of MALAT1 and neighbouring nuclear enriched abundant transcript (NEAT1) documented direct interaction between these lncRNA transcripts.

Conclusion

The data suggest a molecular circuit involving the MALAT1-mascRNA system, interactions between MALAT1 and NEAT1, and key immune effector molecules, cumulatively impacting upon the development of atherosclerosis. It appears reasonable to look for therapeutic targets in this circuit and to screen for anomalies in the NEAT1-MALAT1 region in humans, too, as possible novel disease risk factors.

FMRpolyG accumulates in FMR1 premutation granulosa cells

Background

Fragile X premutation (Amplification of CGG number 55–200) is associated with increased risk for fragile X-Associated Premature Ovarian Insufficiency (FXPOI) in females and fragile X-associated tremor/ataxia syndrome (FXTAS) predominantly in males. Recently, it has been shown that CGG repeats trigger repeat associated non-AUG initiated translation (RAN) of a cryptic polyglycine-containing protein, FMRpolyG. This protein accumulates in ubiquitin-positive inclusions in neuronal brain cells of FXTAS patients and may lead to protein-mediated neurodegeneration. FMRpolyG inclusions were also found in ovary stromal cells of a FXPOI patient. The role of FMRpolyG expression has not been thoroughly examined in folliculogenesis related cells. The main goal of this study is to evaluate whether FMRpolyG accumulates in mural granulosa cells of FMR1 premutation carriers. Following FMRpolyG detection, we aim to examine premutation transfected COV434 as a suitable model used to identify RAN translation functions in FXPOI pathogenesis.

Results

FMRpolyG and ubiquitin immunostained mural granulosa cells from six FMR1 premutation carriers demonstrated FMRpolyG aggregates. However, co-localization of FMRpolyG and ubiquitin appeared to vary within the FMR1 premutation carriers’ group as three exhibited partial ubiquitin and FMRpolyG double staining and three premutation carriers demonstrated FMRpolyG single staining. None of the granulosa cells from the five control women expressed FMRpolyG. Additionally, human ovarian granulosa tumor, COV434, were transfected with two plasmids; both expressing 99CGG repeats but only one enables FMRpolyG expression. Like in granulosa cells from FMR1 premutation carriers, FMRpolyG aggregates were found only in COV434 transfected with expended CGG repeats and the ability to express FMRpolyG.

Conclusions

Corresponding with previous studies in FXTAS, we demonstrated accumulation of FMRpolyG in mural granulosa cells of FMR1 premutation carriers. We also suggest that following further investigation, the premutation transfected COV434 might be an appropriate model for RAN translation studies. Detecting FMRpolyG accumulation in folliculogenesis related cells supports previous observations and imply a possible common protein-mediated toxic mechanism for both FXPOI and FXTAS.

The chameleon of cardiology: cardiac sarcoidosis before and after heart transplantation

Cardiac sarcoidosis is a chronic inflammatory disease with a large spectrum of symptoms that can mimic diseases such as dilated, hypertrophic, or arrhythmogenic cardiomyopathies. It can be asymptomatic but can also present with ventricular arrhythmias, conduction disease, and heart failure (HF) or even sudden cardiac death (SCD). We present here the case of a patient transplanted due to end‐stage arrhythmogenic right ventricular cardiomyopathy (ARVC), fulfilling the task force criteria. A few years after successful heart transplantation (HTX), the patient developed similar symptoms and morphofunctional changes of the heart, which led to critical re‐evaluation of his primary diagnosis.

P3688Familial recurrent autoimmune myocarditis associated with a truncating nonsense mutation of the desmoplakin gene

Background

Arrhythmogenic cardiomyopathy (AC) is an important cause of ventricular arrhythmias in children and young adults. AC is associated with mutation of desmosomal proteins, however, cardiac disease penetrance is incomplete and the clinical course varies widely without recognizable exogenous or epi/genetic co-factors. Importantly, DSP mutation carriers may also display entirely non-cardiac e.g. dermatological phenotypes.

Methods and results

In two brothers with recurrent fulminant myocarditis, mutation screening of 218 cardiomyopathy-related genes identified a truncating mutation Arg1458* of desmoplakin (DSP). DSP immunhistology unexpectedly revealed complete loss (“knockout”) of DSP protein in endomyocardial biopsies (EMBs), but none of the histological anomalies of AC. Criteria for histological diagnosis of myocarditis were not either fulfilled, and cardiac MRI revealed no features associated with AC. Screening for infections was negative, there was no substance abuse, medication or vaccination. Possible disease triggers were competitive sport events. Myosin and troponin I autoantibodies were detected at titers up to 1:320.

We used allele-specific RT-PCR to distinguish if the patients' allele classified as “normal” was actually defective due to promotor mutation or epigenetic silencing. RT-PCRs were done on EMBs and peripheral blood mononuclear cells (PBMCs). In a cohort of dilated cardiomyopathy (DCM) patients we were able to detect DSP transcripts in both, PBMC and left-ventricular heart tissue. RNA sequencing of human PBMC subpopulations suggested that DSP transcription may be restricted to certain immune cell subtypes. RT-PCRs revealed that both Arg1458* carriers have a functional second DSP allele, indicating that their “DSP knockout” occurs at the protein level and may be due to protein instability and degradation within desmosomes.

We screened additional existing cohorts for such variants and identified stopgain variant Gln307Ter in a 37-yrs-old woman with ARVC. This patient's sister died from heart failure at the age of 39. In a 59-yrs-old female LVNC patient, stopgain variant Y1391X was identified. Here, family history was unclear, her brother probably died from coronary artery disease. In a 71-yrs-old female DCM patient with no family history, stopgain variant Tyr1512Ter was identified.

Conclusions

The described patients with DSP truncations strongly suggest the existence of additional genetic or exogenous modifiers driving pathogenesis either way. DSP defects may cause recurrent myocarditis, and mutation screening is advisable to enable early detection of high-risk patients with similar phenotypes. Our finding of complete myocardial DSP protein loss emphasizes that DNA sequencing may miss critical molecular disturbances. It is indispensable to also analyze transcriptome and protein level in the tissue actually affected in a patient in order to recognize his/her individual pathogenesis.