Right ventricular remodeling and clinical outcomes following transcatheter tricuspid valve intervention.

AIMS: Characterize the impact of residual tricuspid regurgitation (TR) on right ventricle (RV) remodeling and clinical outcomes after transcatheter tricuspid valve intervention. METHODS: We performed a single-center retrospective analysis of transcatheter tricuspid valve repair (TTVr) or replacement (TTVR) patients. The primary outcomes were longitudinal tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), pulmonary artery systolic pressure (PASP), and RV dimensions (RVd). We used multivariable linear mixed models to evaluate association with replacement versus repair and degree of TR reduction with changes in these echo measures over time. Multivariable Cox regression was used to identify associations between changes in these echo measures and a composite clinical outcome of death, heart failure hospitalization, or re-do tricuspid valve intervention. RESULTS: We included a total of 61 patients; mean age was 77.5 ± 11.7 and 62% were female. TTVR was performed in 25 (41%) and TTVr in 36 (59%). Initially, 72% (n = 44) had ≤ severe TR and 28% (n = 17) had massive or torrential TR. The median number of follow up echos was 2: time to 1st follow-up was 50 days (interquartile range [IQR]: 20, 91) and last follow-up was 147 (IQR: 90, 327). Median TR reduction was 1 (IQR: 0, 2) versus 4 (IQR: 3, 6) grades in TTVr versus TTVR (p < 0.0001). In linear mixed modeling, TTVR was associated with decline in TAPSE and PASP, and TR reduction was associated with decreased RVd. In multivariable Cox regression, greater RVd was associated with the clinical outcome (hazard ratio: 9.27, 95% confidence interval: 1.23-69.88, p = 0.03). CONCLUSION: Greater TR reduction is achieved by TTVR versus TTVr, which is in turn associated with RV reverse remodeling. RV dimension in follow-up is associated with increased risk of a composite outcome of death, heart failure hospitalization, or re-do tricuspid valve intervention.

Tricuspid Valve Academic Research Consortium Definitions for Tricuspid Regurgitation and Trial Endpoints.

Interest in the pathophysiology, etiology, management, and outcomes of patients with tricuspid regurgitation (TR) has grown in the wake of multiple natural history studies showing progressively worse outcomes associated with increasing TR severity, even after adjusting for multiple comorbidities. Historically, isolated tricuspid valve surgery has been associated with high in-hospital mortality rates, leading to the development of transcatheter treatment options. The aim of this first Tricuspid Valve Academic Research Consortium document is to standardize definitions of disease etiology and severity, as well as endpoints for trials that aim to address the gaps in our knowledge related to identification and management of patients with TR. Standardizing endpoints for trials should provide consistency and enable meaningful comparisons between clinical trials. A second Tricuspid Valve Academic Research Consortium document will focus on further defining trial endpoints and will discuss trial design options.

Tricuspid Valve Academic Research Consortium Definitions for Tricuspid Regurgitation and Trial Endpoints.

Interest in the pathophysiology, etiology, management, and outcomes of patients with tricuspid regurgitation (TR) has grown in the wake of multiple natural history studies showing progressively worse outcomes associated with increasing TR severity, even after adjusting for multiple comorbidities. Historically, isolated tricuspid valve surgery has been associated with high in-hospital mortality rates, leading to the development of transcatheter treatment options. The aim of this first Tricuspid Valve Academic Research Consortium document is to standardize definitions of disease etiology and severity, as well as endpoints for trials that aim to address the gaps in our knowledge related to identification and management of patients with TR. Standardizing endpoints for trials should provide consistency and enable meaningful comparisons between clinical trials. A second Tricuspid Valve Academic Research Consortium document will focus on further defining trial endpoints and will discuss trial design options.

Tricuspid Valve Academic Research Consortium Definitions for Tricuspid Regurgitation and Trial Endpoints.

Interest in the pathophysiology, etiology, management, and outcomes of patients with tricuspid regurgitation (TR) has grown in the wake of multiple natural history studies showing progressively worse outcomes associated with increasing TR severity, even after adjusting for multiple comorbidities. Historically, isolated tricuspid valve surgery has been associated with high in-hospital mortality rates, leading to the development of transcatheter treatment options. The aim of this first Tricuspid Valve Academic Research Consortium document is to standardize definitions of disease etiology and severity, as well as endpoints for trials that aim to address the gaps in our knowledge related to identification and management of patients with TR. Standardizing endpoints for trials should provide consistency and enable meaningful comparisons between clinical trials. A second Tricuspid Valve Academic Research Consortium document will focus on further defining trial endpoints and will discuss trial design options.

KAT2 paralogs prevent dsRNA accumulation and interferon signaling to maintain intestinal stem cells.

Histone acetyltransferases KAT2A and KAT2B are paralogs highly expressed in the intestinal epithelium, but their functions are not well understood. In this study, double knockout of murine Kat2 genes in the intestinal epithelium was lethal, resulting in robust activation of interferon signaling and interferon-associated phenotypes including the loss of intestinal stem cells. Use of pharmacological agents and sterile organoid cultures indicated a cell-intrinsic double-stranded RNA trigger for interferon signaling. Acetyl-proteomics and dsRIP-seq were employed to interrogate the mechanism behind this response, which identified mitochondria-encoded double-stranded RNA as the source of intrinsic interferon signaling. Kat2a and Kat2b therefore play an essential role in regulating mitochondrial functions as well as maintaining intestinal health.

Therapy-induced APOBEC3A drives evolution of persistent cancer cells.

Acquired drug resistance to anticancer targeted therapies remains an unsolved clinical problem. Although many drivers of acquired drug resistance have been identified1-4, the underlying molecular mechanisms shaping tumour evolution during treatment are incompletely understood. Genomic profiling of patient tumours has implicated apolipoprotein B messenger RNA editing catalytic polypeptide-like (APOBEC) cytidine deaminases in tumour evolution; however, their role during therapy and the development of acquired drug resistance is undefined. Here we report that lung cancer targeted therapies commonly used in the clinic can induce cytidine deaminase APOBEC3A (A3A), leading to sustained mutagenesis in drug-tolerant cancer cells persisting during therapy. Therapy-induced A3A promotes the formation of double-strand DNA breaks, increasing genomic instability in drug-tolerant persisters. Deletion of A3A reduces APOBEC mutations and structural variations in persister cells and delays the development of drug resistance. APOBEC mutational signatures are enriched in tumours from patients with lung cancer who progressed after extended responses to targeted therapies. This study shows that induction of A3A in response to targeted therapies drives evolution of drug-tolerant persister cells, suggesting that suppression of A3A expression or activity may represent a potential therapeutic strategy in the prevention or delay of acquired resistance to lung cancer targeted therapy.

Effect of venoarterial extracorporeal membrane oxygenation initiation timing on tricuspid valve surgery outcomes.

Objectives: Tricuspid valve surgery is associated with high rates of shock and in-hospital mortality. Early initiation of venoarterial extracorporeal membrane oxygenation after surgery may provide right ventricular support and improve survival. We evaluated mortality in patients undergoing tricuspid valve surgery based on the timing of venoarterial extracorporeal membrane oxygenation. Methods: All consecutive adult patients undergoing isolated or combined surgical tricuspid valve repair or replacement from 2010 to 2022 requiring venoarterial extracorporeal membrane oxygenation use were stratified by initiation in the operating room (Early) versus outside of the operating room (Late). Variables associated with in-hospital mortality were explored using logistic regression. Results: There were 47 patients who required venoarterial extracorporeal membrane oxygenation: 31 Early and 16 Late. Mean age was 55.6 years (standard deviation, 16.8), 25 (54.3%) were in New York Heart Association class III/IV, 30 (60.8%) had left-sided valve disease, and 11 (23.4%) had undergone prior cardiac surgery. Median left ventricular ejection fraction was 60.0% (interquartile range, 45-65), right ventricular size was moderately to severely increased in 26 patients (60.5%), and right ventricular function was moderately to severely reduced in 24 patients (51.1%). Concomitant left-sided valve surgery was performed in 25 patients (53.2%). There were no differences in baseline characteristics or invasive measurements immediately before surgery between the Early and Late groups. Venoarterial extracorporeal membrane oxygenation was initiated 194 (23.0-840.0) minutes after cardiopulmonary bypass in the Late venoarterial extracorporeal membrane oxygenation group. In-hospital mortality was 35.5% (n = 11) in the Early group versus 68.8% (n = 11) in the Late group (P = .037). Late venoarterial extracorporeal membrane oxygenation was associated with in-hospital mortality (odds ratio, 4.00; 1.10-14.50; P = .035). Conclusions: Early postoperative initiation of venoarterial extracorporeal membrane oxygenation after tricuspid valve surgery in high-risk patients may be associated with improvement in postoperative hemodynamics and in-hospital mortality.

Evolutionary dynamics between transposable elements and their host genomes: mechanisms of suppression and escape.

Transposable elements (TEs) are ubiquitous among eukaryotic species. Their evolutionary persistence is likely due to a combination of tolerogenic, evasive/antagonistic, and cooperative interactions with their host genomes. Here, we focus on metazoan species and review recent advances related to the harmful effects of TE insertions, including how epigenetic effects and TE-derived RNAs can damage host cells. We discuss new findings related to host pathways that silence TEs, such as the piRNA pathway and the APOBEC3 and Kruppel-associated box zinc finger gene families. Finally, we summarize novel strategies used by TEs to evade host silencing, including the Y chromosome as a permissive niche for TE mobilization and TE counterdefense strategies to block host silencing factors.

Baseline Characteristics and Clinical Outcomes of a Tricuspid Regurgitation Referral Population.

Adverse outcomes in tricuspid regurgitation (TR) have been associated with advanced regurgitation severity and right-sided cardiac remodeling, and late referrals for tricuspid valve surgery in TR have been associated with increase in postoperative mortality. The purpose of this study was to evaluate baseline characteristics, clinical outcomes, and procedural utilization of a TR referral population. We analyzed patients with a diagnosis of TR referred to a large TR referral center between 2016 and 2020. We evaluated baseline characteristics stratified by TR severity and analyzed time-to-event outcomes for a composite of overall mortality or heart-failure hospitalization. In total, 408 patients were referred with a diagnosis of TR: the median age of the cohort was 79 years (interquartile range 70 to 84), and 56% were female. In patients evaluated on a 5-grade scale, 10.2% had ≤moderate TR; 30.7% had severe TR; 11.4% had massive TR, and 47.7% had torrential TR. Increasing TR severity was associated with right-sided cardiac remodeling and altered right ventricular hemodynamics. In multivariable Cox regression analysis, New York Heart Association class symptoms, history of heart failure hospitalization, and right atrial pressure were associated with the composite outcome. One-third of patients referred underwent transcatheter tricuspid valve intervention (19%) or surgery (14%); patients who underwent transcatheter tricuspid valve intervention had greater preoperative risk than that of patients who underwent surgery. In conclusion, in patients referred for evaluation of TR, there were high rates of massive and torrential regurgitation and advanced right ventricle remodeling. Symptoms and right atrial pressure are associated with clinical outcomes in follow-up. There were significant differences in baseline procedural risk and eventual therapeutic modality.

Mode and Tempo of 3D Genome Evolution in Drosophila.

Topologically associating domains (TADs) are thought to play an important role in preventing gene misexpression by spatially constraining enhancer-promoter contacts. The deleterious nature of gene misexpression implies that TADs should, therefore, be conserved among related species. Several early studies comparing chromosome conformation between species reported high levels of TAD conservation; however, more recent studies have questioned these results. Furthermore, recent work suggests that TAD reorganization is not associated with extensive changes in gene expression. Here, we investigate the evolutionary conservation of TADs among 11 species of Drosophila. We use Hi-C data to identify TADs in each species and employ a comparative phylogenetic approach to derive empirical estimates of the rate of TAD evolution. Surprisingly, we find that TADs evolve rapidly. However, we also find that the rate of evolution depends on the chromatin state of the TAD, with TADs enriched for developmentally regulated chromatin evolving significantly slower than TADs enriched for broadly expressed, active chromatin. We also find that, after controlling for differences in chromatin state, highly conserved TADs do not exhibit higher levels of gene expression constraint. These results suggest that, in general, most TADs evolve rapidly and their divergence is not associated with widespread changes in gene expression. However, higher levels of evolutionary conservation and gene expression constraints in TADs enriched for developmentally regulated chromatin suggest that these TAD subtypes may be more important for regulating gene expression, likely due to the larger number of long-distance enhancer-promoter contacts associated with developmental genes.

Incidence and predictors of cardiogenic shock following surgical or transcatheter tricuspid valve intervention.

OBJECTIVE: The objective of this study was to evaluate the incidence of and risk factors associated with cardiogenic shock (CS) following surgery versus transcatheter tricuspid valve intervention (TTVI) for tricuspid regurgitation (TR). BACKGROUND: Surgical therapy for TR is associated with high rates of CS. Postprocedural shock has not been studied following TTVI. METHODS: We performed a single-center retrospective analysis of isolated tricuspid valve (TV) surgery or TTVI for TR. The primary outcome was postprocedural class D or E CS according to Society for Cardiovascular Angiography and Interventions (SCAI) CS classification scheme, and secondary outcome was in-hospital mortality. Multivariable logistic regression modeling was performed for primary and secondary outcomes. Support vector machine analysis was performed for sensitivity analysis. RESULTS: From 2008 to 2020, a total of 122 patients underwent isolated TV surgery (n = 58, 14 TV repair, and 44 TV replacement) or TTVI (n = 64, 36 TV repair, and 28 TV replacement). Surgical patients were significantly younger than TTVI patients (67.5 vs. 80 years, p < 0.0001). Multivariable modeling revealed an association between the primary outcome and surgery (odds ratio [OR]: 8.75, 95% confidence interval [CI]: 2.83, 27.03, p = 0.0002), as well as baseline central venous pressure (CVP, OR: 1.12, 95% CI: 1.02, 1.22, p = 0.016). Additionally, class DE CS was independently associated with in-hospital mortality (OR: 5.21, 1.35, 20.09, p = 0.016). CVP and surgery were found to have highest importance indices in support vector machine analysis. CONCLUSION: In patients undergoing TV intervention for TR, surgery versus TTVI and elevated CVP are associated with advanced postprocedural CS. Patients developing advanced CS are at increased risk of in-hospital mortality.

A transposon expression burst accompanies the activation of Y-chromosome fertility genes during Drosophila spermatogenesis.

Transposable elements (TEs) must replicate in germline cells to pass novel insertions to offspring. In Drosophila melanogaster ovaries, TEs can exploit specific developmental windows of opportunity to evade host silencing and increase their copy numbers. However, TE activity and host silencing in the distinct cell types of Drosophila testis are not well understood. Here, we reanalyze publicly available single-cell RNA-seq datasets to quantify TE expression in the distinct cell types of the Drosophila testis. We develop a method for identification of TE and host gene expression modules and find that a distinct population of early spermatocytes expresses a large number of TEs at much higher levels than other germline and somatic components of the testes. This burst of TE expression coincides with the activation of Y chromosome fertility factors and spermatocyte-specific transcriptional regulators, as well as downregulation of many components of the piRNA pathway. The TEs expressed by this cell population are specifically enriched on the Y chromosome and depleted on the X chromosome, relative to other active TEs. These data suggest that some TEs may achieve high insertional activity in males by exploiting a window of opportunity for mobilization created by the activation of spermatocyte-specific and Y chromosome-specific transcriptional programs.

Selective targeting of MYC mRNA by stabilized antisense oligonucleotides.

MYC is a prolific proto-oncogene driving the malignant behaviors of numerous common cancers, yet potent and selective cell-permeable inhibitors of MYC remain elusive. In order to ultimately realize the goal of therapeutic MYC inhibition in cancer, we have initiated discovery chemistry efforts aimed at inhibiting MYC translation. Here we describe a series of conformationally stabilized synthetic antisense oligonucleotides designed to target MYC mRNA (MYCASOs). To support bioactivity, we designed and synthesized this focused library of MYCASOs incorporating locked nucleic acid (LNA) bases at the 5'- and 3'-ends, a phosphorothioate backbone, and internal DNA bases. Treatment of MYC-expressing cancer cells with MYCASOs leads to a potent decrease in MYC mRNA and protein levels. Cleaved MYC mRNA in MYCASO-treated cells is detected with a sensitive 5' Rapid Amplification of cDNA Ends (RACE) assay. MYCASO treatment of cancer cell lines leads to significant inhibition of cellular proliferation while specifically perturbing MYC-driven gene expression signatures. In a MYC-induced model of hepatocellular carcinoma, MYCASO treatment decreases MYC protein levels within tumors, decreases tumor burden, and improves overall survival. MYCASOs represent a new chemical tool for in vitro and in vivo modulation of MYC activity, and promising therapeutic agents for MYC-addicted tumors.

Association between antecedent statin use and decreased mortality in hospitalized patients with COVID-19.

The coronavirus disease 2019 (COVID-19) can result in a hyperinflammatory state, leading to acute respiratory distress syndrome (ARDS), myocardial injury, and thrombotic complications, among other sequelae. Statins, which are known to have anti-inflammatory and antithrombotic properties, have been studied in the setting of other viral infections, but their benefit has not been assessed in COVID-19. This is a retrospective analysis of patients admitted with COVID-19 from February 1st through May 12th, 2020 with study period ending on June 11th, 2020. Antecedent statin use was assessed using medication information available in the electronic medical record. We constructed a multivariable logistic regression model to predict the propensity of receiving statins, adjusting for baseline sociodemographic and clinical characteristics, and outpatient medications. The primary endpoint includes in-hospital mortality within 30 days. A total of 2626 patients were admitted during the study period, of whom 951 (36.2%) were antecedent statin users. Among 1296 patients (648 statin users, 648 non-statin users) identified with 1:1 propensity-score matching, statin use is significantly associated with lower odds of the primary endpoint in the propensity-matched cohort (OR 0.47, 95% CI 0.36-0.62, p < 0.001). We conclude that antecedent statin use in patients hospitalized with COVID-19 is associated with lower inpatient mortality.

A Tumor Suppressor Enhancer of PTEN in T-cell development and leukemia.

Long-range oncogenic enhancers play an important role in cancer. Yet, whether similar regulation of tumor suppressor genes is relevant remains unclear. Loss of expression of PTEN is associated with the pathogenesis of various cancers, including T-cell leukemia (T-ALL). Here, we identify a highly conserved distal enhancer (PE) that interacts with the PTEN promoter in multiple hematopoietic populations, including T-cells, and acts as a hub of relevant transcription factors in T-ALL. Consistently, loss of PE leads to reduced PTEN levels in T-ALL cells. Moreover, PE-null mice show reduced Pten levels in thymocytes and accelerated development of NOTCH1-induced T-ALL. Furthermore, secondary loss of PE in established leukemias leads to accelerated progression and a gene expression signature driven by Pten loss. Finally, we uncovered recurrent deletions encompassing PE in T-ALL, which are associated with decreased PTEN levels. Altogether, our results identify PE as the first long-range tumor suppressor enhancer directly implicated in cancer.

Admission Cardiac Diagnostic Testing with Electrocardiography and Troponin Measurement Prognosticates Increased 30-Day Mortality in COVID-19.

Background Cardiovascular involvement in coronavirus disease 2019 (COVID-19) is common and leads to worsened mortality. Diagnostic cardiovascular studies may be helpful for resource appropriation and identifying patients at increased risk for death. Methods and Results We analyzed 887 patients (aged 64±17 years) admitted with COVID-19 from March 1 to April 3, 2020 in New York City with 12 lead electrocardiography within 2 days of diagnosis. Demographics, comorbidities, and laboratory testing, including high sensitivity cardiac troponin T (hs-cTnT), were abstracted. At 30 days follow-up, 556 patients (63%) were living without requiring mechanical ventilation, 123 (14%) were living and required mechanical ventilation, and 203 (23%) had expired. Electrocardiography findings included atrial fibrillation or atrial flutter (AF/AFL) in 46 (5%) and ST-T wave changes in 306 (38%). 27 (59%) patients with AF/AFL expired as compared to 181 (21%) of 841 with other non-life-threatening rhythms (P<0.001). Multivariable analysis incorporating age, comorbidities, AF/AFL, QRS abnormalities, and ST-T wave changes, and initial hs-cTnT ≥20 ng/L showed that increased age (HR 1.04/year), elevated hs-cTnT (HR 4.57), AF/AFL (HR 2.07), and a history of coronary artery disease (HR 1.56) and active cancer (HR 1.87) were associated with increased mortality. Conclusions Myocardial injury with hs-cTnT ≥20 ng/L, in addition to cardiac conduction perturbations, especially AF/AFL, upon hospital admission for COVID-19 infection is associated with markedly increased risk for mortality than either diagnostic abnormality alone.

The Prognostic Value of Electrocardiogram at Presentation to Emergency Department in Patients With COVID-19.

OBJECTIVE: To study whether combining vital signs and electrocardiogram (ECG) analysis can improve early prognostication. METHODS: This study analyzed 1258 adults with coronavirus disease 2019 who were seen at three hospitals in New York in March and April 2020. Electrocardiograms at presentation to the emergency department were systematically read by electrophysiologists. The primary outcome was a composite of mechanical ventilation or death 48 hours from diagnosis. The prognostic value of ECG abnormalities was assessed in a model adjusted for demographics, comorbidities, and vital signs. RESULTS: At 48 hours, 73 of 1258 patients (5.8%) had died and 174 of 1258 (13.8%) were alive but receiving mechanical ventilation with 277 of 1258 (22.0%) patients dying by 30 days. Early development of respiratory failure was common, with 53% of all intubations occurring within 48 hours of presentation. In a multivariable logistic regression, atrial fibrillation/flutter (odds ratio [OR], 2.5; 95% CI, 1.1 to 6.2), right ventricular strain (OR, 2.7; 95% CI, 1.3 to 6.1), and ST segment abnormalities (OR, 2.4; 95% CI, 1.5 to 3.8) were associated with death or mechanical ventilation at 48 hours. In 108 patients without these ECG abnormalities and with normal respiratory vitals (rate <20 breaths/min and saturation >95%), only 5 (4.6%) died or required mechanical ventilation by 48 hours versus 68 of 216 patients (31.5%) having both ECG and respiratory vital sign abnormalities. CONCLUSION: The combination of abnormal respiratory vital signs and ECG findings of atrial fibrillation/flutter, right ventricular strain, or ST segment abnormalities accurately prognosticates early deterioration in patients with coronavirus disease 2019 and may assist with patient triage.

Association Between Antecedent Statin Use and Decreased Mortality in Hospitalized Patients with COVID-19.

The coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), can result in a hyperinflammatory state, leading to acute respiratory distress syndrome (ARDS), myocardial injury, and thrombotic complications, among other sequelae. Statins, which are known to have anti-inflammatory and antithrombotic properties, have been studied in the setting of other viral infections and ARDS, but their benefit has not been assessed in COVID-19. Thus, we sought to determine whether antecedent statin use is associated with lower in-hospital mortality in patients hospitalized for COVID-19. This is a retrospective analysis of patients admitted with COVID-19 from February 1 st through May 12 th , 2020 with study period ending on June 11 th , 2020. Antecedent statin use was assessed using medication information available in the electronic medical record. We constructed a multivariable logistic regression model to predict the propensity of receiving statins, adjusting for baseline socio-demographic and clinical characteristics, and outpatient medications. The primary endpoint included in-hospital mortality within 30 days. A total of 2626 patients were admitted during the study period, of whom 951 (36.2%) were antecedent statin users. Among 1296 patients (648 statin users, 648 non-statin users) identified with 1:1 propensity-score matching, demographic, baseline, and outpatient medication information were well balanced. Statin use was significantly associated with lower odds of the primary endpoint in the propensity-matched cohort (OR 0.48, 95% CI 0.36 â€" 0.64, p<0.001). We conclude that antecedent statin use in patients hospitalized with COVID-19 was associated with lower inpatient mortality. Randomized clinical trials evaluating the utility of statin therapy in patients with COVID-19 are needed.