bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 15382: Variant Subtype and Regionality Aid Assessment of Pathogenicity in
Plakophillin-2
(
PKP2
)
Authors: Dries Annika , Kirillova Anna , Reuter Chloe , Zouk Hana , Hawley Megan , Tichnell Crystal , Murray Brittney , Funke Birgit , Garcia John , Haggerty Christopher M , James Cynthia , Parikh Victoria
Published: May 2021

Loss of function variants in
PKP2
are associated with Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC), but little is known about the consequences of
PKP2
missense variation. We hypothesized that truncating variants in
PKP2
are more likely to be associated with cardiomyopathy than missense, and that the pathogenicity of
PKP2
missense variants varies by gene region
.
We assembled genetic tests from probands with variants in
PKP2
and ARVC-relevant diagnoses from industry partners (N=176) and evaluated the proportion of probands with truncating (N=98) and missense (N=78) variants in this disease-associated population vs. the general population (represented by gnomAD: N=97 truncating; N=12408 missense). Truncating variants were enriched in the disease-associated population (OR=160.7, p<0.0001), while missense variants were not. To identify potential hotspots for pathogenic missense variation, we examined the proportion of probands with disease-associated vs. general population-associated missense variants within sliding windows across the length of the
PKP2
transcript. We found 18 windows enriched for diseased probands with missense variants, one of which lies within a known functional domain (FDR=0.001, Figure 1). We then performed a variant-level analysis on independent publicly available databases of ARVC-associated variants (University Medical Center Groningen and ClinVar, N=44 vs. gnomAD, N=546), and found two of the same windows (FDR=0.2). Four out of six
PKP2
missense variants listed as pathogenic in ClinVar fell within disease-associated windows. Truncating
PKP2
variants are more likely to be associated with disease than missense variants. Examination of disease-associated regions of missense variation in
PKP2
identified potential hotspots for pathogenicity. Future directions include further validation based on highly clinically adjudicated ARVC populations and
in vitro
examination of functional relevance of these domains.
Abstract 15385: A Tapered BP Cuff More Accurately Measures Systolic Blood Pressure Than Does a Standard Rectangular BP Cuff Over a Range of Arm Circumferences
Authors: Gloth Sean T , Ambinder Daniel I , Whitman Glenn , Schulman Steven P , Brinker Jeffrey A , Gerstenblith Gary
Published: May 2021

Introduction:
Systolic blood pressure (BP) is an important risk factor for cardiovascular outcomes. However, non-invasive measures obtained using a standard rectangular cuff (RC) are accurate only when the width of the cuff is ~40% of the arm circumference (AC). This ideal Ratio (IR) is met for the medium standard rectangular cuff at an AC of 30 cm.

Hypothesis:
A tapered cuff (TC) designed to maintain the IR over a range of ACs more accurately measures systolic BP than does a standard rectangular cuff.

Methods:
Twenty-two measures of BP using the RC and the TC were compared in seven patients with ACs of 30 cm. In addition, twenty-seven measures of SBP using the RC and the TC were compared with radial artery pressures in 12 patients with clinically placed arterial lines and arm circumferences ranging from 24 cm to 38 cm.

Results:
When ACs were 30 cm, there was no significant difference between the RC and SC systolic pressures (mean ± SD difference of 1.3 mmHg ± 0.8, p=.78) and they correlated with one another, R
2
of 0.99. However, over a range of ACs, the RC systolic pressures significantly differed from the arterial pressures (mean difference ± SD of 11 ± 4 mmHg, p=.005), and did not correlate with the arterial readings (Panel A) , whereas the TC systolic pressures did not differ from the arterial pressures (mean difference ± SD of 2 ± 1.3 mmHg, p=.18) and did correlate with the arterial readings (Panel B).

Conclusion:
Systolic BPs obtained with a TC which maintains the IR over a continuous range of arm circumferences are more accurate than are those obtained with a RC.
Abstract 15505: Aortic Stiffening in L-NAME Treated C57bl6 Mice Precedes Peripheral Hypertension and Cardiac Hypertrophy: Early Endothelial Dysfunction Shifts to Late-term Vascular Smooth Muscle Cell Disease
Authors: De Moudt Sofie , Hendrickx Jhana O , De Munck Dorien G , Leloup Arthur , Martinet Wim , De Meyer Guido , Fransen Paul
Published: May 2021

Introduction:
Endothelial dysfunction (ED) acts as a common player in most cardiovascular (CV) risk factors (e.g. hypertension, smoking) underlining its importance in CV ageing. Therefore, this study aims to characterize
ex vivo
aortic function changes in Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME) treated mice.

Methods:
C57Bl6 mice (male, n=10) received 0.5 mg/mL L-NAME through the drinking water for 1, 2, 4, 8, and 16 weeks, followed by in-depth
ex vivo
thoracic aorta isometric reactivity studies and arterial stiffness (Peterson modulus, Ep) measurements in the Rodent Oscillatory Tension set-up for Arterial Compliance (ROTSAC). In addition, peripheral blood pressure (BP, Coda), aortic pulse wave velocity (aPWV, Vevo2100), and echocardiography (Vevo2100) were measured
in vivo
. (Data are represented as mean±SEM)

Results:
L-NAME treated mice display fast-onset aortic stiffening after 1-week L-NAME (Fig. A, B), followed by the development of peripheral hypertension (Fig. C) and cardiac disease (Fig. D-F) after 4-weeks L-NAME.
Ex vivo
aorta studies reveal different stages of disease. Early on (1-4 weeks), mice show elevated phenylephrine (PE) contractions (Fig. G) and impaired acetylcholine (ACh) relaxations (Fig. H), consistent with L-NAME related ED. After 8 weeks, endothelial function and PE contractions normalize. Relaxations to exogenous NO remain unaltered (Fig. I). In contrast to the recovery of ACh relaxations, stiffness analysis in the ROTSAC reveals constantly reduced basal NO levels (Fig. J), and a late-term shift (16 weeks) towards vascular smooth muscle cell (VSMC) disease. This involves basal cytoplasmic calcium loading (Fig. K) and a sharply increasing contribution of voltage-gated calcium channels (Fig. L).

Conclusions:
NOS inhibition by L-NAME treatment causes a distinct time-dependent aortic disease phenotype, underlying fast-onset arterial stiffening which precedes peripheral hypertension and cardiac disease.
Abstract 15506: Inhibition of Angiotensin II Type I Receptor Induces Dual Modification of Mitochondrial Dynamics and Mitophagy via Inactivation of Ras/raf/mek Pathway and Contributes Vascular Anti-senescence
Authors: Uchikado Yoshihiro , Ikeda Yoshiyuki , Sasaki Yuichi , Akasaki Yuichi , Ohishi Mitsuru
Published: May 2021

Introduction:
Angiotensin II (Ang II) causes vascular senescence by damaging mitochondria that undergo quality control by mitochondrial dynamics and mitophagy. We examined whether and how AngII type I receptor (AT1R) signal regulates mitochondrial dynamics and mitophagy in the etiology of vascular senescence.

Methods:
We used vascular smooth muscle cells (VSMC) and C57BL6 (WT), apolipoprotein E deficient (ApoE KO) and the double knockout of ApoE and AT1R mice.

Results:
Administration of Ang II to VSMC forced mitochondria to fission and induced cellular senescence and mitochondrial dysfunction, which were restored by inhibition of fission by use of Mdivi-1. Treatment of ox-LDL also induced cellular senescence accompanied by excessive mitochondrial fission through phosphorylation of Drp1 at Ser616 and mitochondrial dysfunction. These alterations were ameliorated by inhibition of AT1R signal, suggesting that AT1R signal inhibition may contribute anti-cellular senescence by modification of mitochondrial dynamics. AT1R signal inhibition also induced mitophagy assessed by electron microscopy and immunohistochemistry of LAMP2 and TOMM20. AT1R inhibition-induced mitophagy was not affected by Atg7 Knockdown, whereas it was diminished by Rab9 knockdown. Immunohistochemistry showed TOMM20 dots were co-localized to LAMP2 and Rab9 but not LC3. These results suggest that AT1R signal induces mitophagy derived from Rab9-dependent alternative autophagy. Treatment of ox-LDL activated Ras, Raf and MEK, and AT1R inhibition inactivated them. Inhibition of Ras/Raf/MEK decreased excessive mitochondrial fission and induced mitophagy, suggesting that AT1R signal followed by Ras/Raf/MEK pathway modulates both mitochondrial dynamics and mitophagy. The degree of arterial senescence and atherosclerosis, Drp1 expression in mitochondrial fraction and oxidative stress in artery were higher and the number of mitophagy, fused mitochondria and its function were lower in ApoE KO than those of WT mice. AT1R KO to ApoE KO attenuated these adverse effects of ApoE KO.

Conclusions:
Inhibition of AT1R signal contributes vascular senescence through modification of mitochondrial dynamics and mitophagy by inactivation of Ras/Raf/MEK pathway.
Abstract 15510: Trials of Dual Antiplatelet Therapy Do Not Include Evidence-Based Strategies for Gastrointestinal Bleeding Prevention
Authors: Kurlander Jacob E , Barnes Geoffrey , Sukul Devraj , Helminski Danielle , Kokaly Alex , Platt Kevin , Gurm Hitinder S , Saini Sameer
Published: May 2021

Background:
Proton pump inhibitors (PPIs) substantially reduce the risk of upper gastrointestinal bleeding (GIB) and are recommended for high-risk patients by professional cardiology societies but remain underused in clinical practice. By reducing hemorrhagic risk associated with dual antiplatelet therapy (DAPT), PPIs may affect the risk-benefit equation of varying durations of DAPT and should be considered in such clinical trials. We sought to determine the extent to which randomized controlled trials (RCTs) evaluating DAPT after percutaneous coronary intervention (PCI) provide guidance on the use of PPIs for GIB prevention.

Methods:
A previously completed systematic review was updated to identify all RCTs comparing varying durations of DAPT between June 1983 and October 2019. Primary publications, online supplements, clinical trial registries and additional publications linked to the trial registration number were reviewed for protocol information.

Results:
Of 21 included studies (n=58,625; Figure), none of the study protocols provided guidance on the use of PPIs by trial participants. One study stated that the decision to use PPIs was left to the discretion of the treating physician. Two studies specified that treating physicians could prescribe non-mandated medications concordant with standard of care but did not specifically mention PPIs. Only 5 studies reported rates of PPI use, which ranged from 25.6-69.1%.

Conclusions:
Trials of DAPT regimens did not provide guidance on the use of PPI gastroprotection, a guideline-supported strategy for prevention of bleeding from the GI tract, the most common site of bleeding in patients using DAPT. Guidance on and reporting of PPI use should be mandatory in future antithrombotic trials to enhance their safety and interpretability. Figure 1. PRISMA flow diagram
Abstract 15512: Predictors of Normalization of Left Ventricular Systolic Function After Acute Myocarditis -multicenter Observational Study
Authors: Yoshida Ayano , Jujo Kentaro , Shibahashi Eiji , Takada Takuma , Minami Yuichiro , Saito Chihiro , Kyomi Ashihara , Hagiwara Nobuhisa
Published: May 2021

Introduction:
The clinical presentation of acute myocarditis is highly variable, and its prognosis is occasionally unpredictable. Even the patients discharge alive, left ventricular (LV) remodeling occurs during the follow-up period in some cases, which causes the progression of dilated cardiomyopathy or sudden cardiac death.

Purpose:
We aimed to investigate the predictors of the recovery of LV ejection fraction (LVEF) in patients with acute myocarditis.

Methods:
This multicenter observational study included 20 patients [average age 38 years, 18 (90%) male] suffering acute myocarditis who were urgently hospitalized between 2007 and 2019. Enrolled patients were assigned into 2 groups depending on a recovery of LV function that was defined as LVEF ≥55% by transthoracic echocardiography (TTE) within 12 months after the onset; the Recovery group (n=8) and Non-recovery group (n=12).

Results:
Overall, LVEF increased from 37% to 52% (p<0.001) during the follow-up period (median interval: 180 (IQR: 42-332) days). There was no statistically differences in baseline clinical profiles or medications at discharge between the groups. However, LVEF at admission was significantly higher in the Recovery group than Non-recovery group (47±13% vs. 31±13%, p=0.014). The univariate logistic regression analysis showed that baseline LVEF was related to a recovery of LV function (odds ratio, 1.12; 95% confidence interval, 1.00-1.26). The ROC curve for a recovery of LV function revealed that the cut-off value of LVEF at admission was 42% (sensitivity: 75%, specificity: 83%, area under the curve: 0.83,
Figure A
). Patients with baseline LVEF ≥42% achieved significantly higher rates of LV functional recovery after acute myocarditis than those with LVEF <42% (17% vs 75%, p=0.019,
Figure B
).

Conclusions:
Baseline LVEF could predict a normalization of LV function in patients with acute myocarditis. Close observation and TTE follow-up should be considered in such a refractory population.
Abstract 15519: The Prognostic Impact of Transcardiac Gradient of Follistatin-like 1 in Patients With Non-ischemic Dilated Cardiomyopathy
Authors: Oishi Hideo , OKUMURA TAKAHIRO , Ohashi Koji , Kimura Yuki , Kazama Shingo , Shibata Naoki , Arao Yoshihito , Kato Hiroo , Kuwayama Tasuku , Yamaguchi Shogo , Kondo Toru , Hiraiwa Hiroaki , Morimoto Ryota , Ouchi Noriyuki , Murohara Toyoaki
Published: May 2021

Introduction:
Follistatin-like 1 (FSTL1) is secreted from various tissues including myocardium and could play a cardioprotective role against harmful stimuli. It has been shown that the expression of FSTL1 protein in patients with heart failure is higher than that in healthy subjects. However, little is known about the association between serum FSTL1 levels and the cardiac prognosis.

Hypothesis:
We hypothesized that the transcardiac gradient of FSTL1 reflect myocardial FSTL1 and is useful for predicting prognosis in patients with non-ischemic dilated cardiomyopathy (NIDCM).

Methods:
Thirty-two NIDCM patients were enrolled. Blood samples were simultaneously collected from the aortic root (Ao), coronary sinus (CS) as well as peripheral vein during cardiac catheterization. The transcardiac gradient of FSTL1 was calculated by the difference between serum FSTL1 levels of CS and Ao (FSTL1
CS-Ao
). Patients were divided into two groups at the median of FSTL1
CS-Ao
: Low FSTL1
CS-Ao
group, <0 ng/mL; High- FSTL1
CS-Ao
group, > 0 ng/mL. The primary endpoint of this study was the occurrence of a cardiac event, which was defined as a composite of cardiac deaths and unexpected hospitalizations for worsening heart failure.

Results:
The median plasma B type natriuretic levels and mean left ventricular ejection fraction in the Low and High FSTL1
CS-Ao
groups were 91.9 (21.7 - 277.5) vs. 94.1 (59.1 - 236.5) pg/mL (P = 1.000) and 31.4 ± 6.5 vs. 30.5 ± 7.3 % (P = 0.714), respectively. FSTL1
CS-Ao
was negatively correlated with pulmonary capillary wedge pressure (R = -0.400, P = 0.023), mean pulmonary artery pressure (R = -0.40, P = 0.023) and right atrial pressure (R = -0.41, P = 0.019). Kaplan-Meier analysis showed that event-free survival rate was significantly lower in the Low FSTL1
CS-Ao
group (p=0.0126).

Conclusions:
Transcardiac gradient of FSTL1 is associated with hemodynamics and low transcardiac gradient of FSTL1 might be associated with poor prognosis in NIDCM patients.
Abstract 15520: Prognostic Value of Soluble ST2 Measurements for Morbidity and Mortality in Ambulatory Patients With HFpEF
Authors: Gong Alexander O , Balac Nina , Patel Sagar V , Hwang Jennifer , McLeod Jennifer M , Grazette Luanda P
Published: May 2021

Background:
Soluble ST2 (sST2) has emerged as a powerful prognostic marker in chronic systolic heart failure with reduced ejection fraction (HFrEF). Elevated levels of sST2 are associated with adverse cardiac remodeling and fibrosis. However, few studies have investigated the relative prognostic value of sST2 collected from ambulatory patients with chronic heart failure with preserved ejection fraction (HFpEF) for long term outcomes.

Hypothesis:
We sought to determine the prognostic utility of a baseline sST2 partition value in the ambulatory setting as it related to risk for heart failure hospitalization and all-cause mortality.

Methods:
Single-center, retrospective observational study of subjects presenting to an ambulatory heart failure (HF) clinic from July 2014 to December 2016. Baseline sST2 levels were available for 156 subjects with stage C heart failure.. For purposes of this analysis in HFpEF, we excluded patients with EF ≤ 40% resulting in a study cohort of 73 subjects. The mean follow-up was 3.09 years ± 1.46 years. Analysis was performed with IBM SPSS Statistics 26. Discrete variables were expressed as counts (percentage) and were compared using the Chi-squared test. Mean differences of continuous variables were expressed as a mean ± standard deviation and compared using the unpaired Student’s
t-
test. The log-rank test (Mantel-Cox) was used to compare survival times on Kaplan-Meier curves.

Results:
Patients who had baseline sST2 ≥ 35 ng/ml were at increased risk for heart failure hospitalization (p=0.189) and all-cause mortality (p=0.073) compared to patients who had sST2 < 35 ng/ml. Patients with sST2 ≥ 35 ng/ml had a mean of 1.03 HF hospitalizations, 24.1% of this group had ≥ 2 HF hospitalizations and 17.2% all-cause mortality. Patients with sST2 < 35 ng/ml had a mean of 0.57 HF hospitalizations, 14.0% had ≥ 2 HF hospitalizations and 4.55% all-cause mortality.

Conclusion:
Subjects with sST2 levels ≥ 35 ng/ml were at increased risk of recurrent hospitalization and all-cause mortality. The results of this study highlight the value of sST2 concentrations as a prognostic biomarker for identifying patients with HFpEF that are at increased risk for morbidity and mortality in the ambulatory setting.
Abstract 15527: Association Between Adrenergic Receptor Modulation and the Risk of Heart Failure: A Two-sample Mendelian Randomization Study
Authors: Baudier Claire , Fougerousse Françoise , Schmidt Amand F , Asselbergs Folkert W , Guedj Mickael , Komajda Michel , Kotecha Dipak , Lumbers Tom , Tyl Benoit
Published: May 2021

Introduction:
The impact of the sympathetic nervous system (SNS) modulation on the risk of heart failure (HF) outside of ß1 receptor blockade remains controversial.

Methods:
We performed a two-sample Mendelian randomization (MR) study using common independent genetic variants located in the cis region of genes encoding the 9 SNS receptors (α1 A, B, D, α2 A, B, C and ß 1, 2 and 3) that were associated at genome-wide significance (P-value ≤ 5х10
–8
) with blood pressure (BP) and/or heart rate (HR) in published genome-wide association studies (GWAS) available for BP and HR. Variants were filtered out by Linkage Disequilibrium clumping (LD R
2
> 0.1) and based on their minor allele frequency (MAF < 0.01). The effects of selected variants on the genetic risk of HF were extracted from a GWAS of HF from the HERMES consortium, based on a non-overlapping sample population. MR estimates were obtained using the Wald estimator for a single variant or the inverse variance weighted method for multiple variants.

Results:
542,362 controls and 40,805 HF cases were evaluated. Independent variants in genes encoding 4 SNS receptors associated with BP or HR were identified as follows: α1A (diastolic BP), α2B (diastolic BP and HR), ß1 and ß2 (diastolic and systolic BP). MR analysis of α1A and ß1, weighted by their effects on diastolic BP, estimated an association with a higher risk of HF, while α2B variants were associated with a lower risk. We found no evidence for an effect of ß2. A similar relationship with systolic BP was found for ß1 and ß2. HR increasing effect of α2B variants was associated with a decreased odd of HF.

Conclusions:
Mindful of pleiotropic effects, these findings are consistent with the known benefits of ß1 blockade in HF and support a similar role for α1A blockade; conversely, they suggest a detrimental lowering effect of BP and HR through α2B modulation that deserves further studies. No evidence for a role of ß2 in HF was found.
Abstract 15529: Multimorbidity Clusters in Patients Presenting to the Emergency Department With Potential Acute Coronary Syndrome
Authors: Breen Katherine , Finnegan Lorna , Vuckovic Karen M , Fink Anne M , Rosamond Wayne D , Devon Holli A
Published: May 2021

Introduction:
The increasing prevalence of multimorbidity (> 2 chronic conditions) is a challenge for healthcare providers and systems. Multimorbidity complicates treatment and increases the risk of adverse outcomes.

Objectives:
To identify multimorbidity classes (clusters of > 2 specific chronic conditions) in a secondary analysis of a multi-site study about symptoms in patients presenting to the emergency department (ED) for potential acute coronary syndrome (ACS).

Hypothesis:
Specific multimorbidity classes can predict an ACS diagnosis.

Methods:
Chronic conditions were measured (Charlson Comorbidity Index and ACS Patient Information Questionnaire) in patients who underwent a cardiac evaluation in the ED. Latent class analysis was used to identify multimorbidity classes, and logistic regression determined whether multimorbidity classes were predictive of being ruled-in versus ruled-out for ACS.

Results:
The sample (
n
= 935) was 38% female, with a mean age of 59 years. Four multimorbidity classes were identified and labeled: High multimorbidity (Class 1, hyperlipidemia, hypertension [HTN], obesity, diabetes, and respiratory disorders); Low multimorbidity (Class 2, obesity); Cardiovascular multimorbidity (Class 3, HTN, hyperlipidemia, and coronary heart disease); and Cardio-oncology multimorbidity (Class 4, HTN, hyperlipidemia, and cancer). Patients in Classes 3 and 4 had a 2.8-fold and 1.7-fold increased risk of ruling-in for ACS compared to those in Class 2 who were half as likely to rule-in for ACS (OR 0.45 95% CI 0.33 to 0.61 p=0.001). Class membership differed by sex, age, and family history. Females were more likely to be in Class 1 (44.2%), younger patients in Class 2 (mean age 43.4 ± 9.8 years), older patients in class 4 (mean age 80.0 ± 6.3 years), and those with a family history of sudden cardiac death (< age 55) in Class 3 (58.3%).

Conclusion:
Multimorbidity classes differed according to demographic and clinical variables. Membership in Classes 3 and 4 were predictive of an ACS diagnosis. Clustering patients by multimorbidity class may inform risk-stratification during evaluation for ACS.
Abstract 15531: Limited Relationship Between Echocardiographic Measures and Electrocardiographic Markers of Left Ventricular Dimensions in Healthy Children
Authors: Alexander Mark E , Gongwer Russell , Trachtenberg Felicia , Minich Luann , Triedman John K , Kaltman Jonathan , Czosek Richard J , Tristani Martin , LaPage Martin J , Tsao Sabrina , Radbill Andrew E , Dilorenzo Michael , Kovach Joshua R , Stephenson Elizabeth A , Janson Christopher , Mao Chad Y , Salerno Jack C , Mahgerefteh Joseph , Pilcher Thomas A , Johnson Tiffanie R , Valdes Santiago O , Jackson Lanier , Saarel Elizabeth V ,   for the Pediatric Heart Network investigators
Published: May 2021

Background:
Prior ECG standards in children have largely been defined without echo confirmation of normal anatomy. The Pediatric Heart Network Normal Echocardiogram Z-score Project provides a racially diverse age/sex classified group of healthy children with normal echos that included 2170 matched contemporaneous digitally acquired ECGs. We hypothesized that ECG measures and z-scores of left ventricular (LV) dimensions are correlated in healthy children.

Methods:
This was a secondary analysis of the previously described cohort. Six ECG measures historically associated with LV size (R V5, R V6, S V1, Q III, axis, R V6+S V1), and 13 paired echo measures were identified a-priori with LV Mass (LVMass-z) and left ventricular end diastolic volume (LVEDV-z) z-scores serving as primary echo measurement predictors. Pearson or Spearman correlations were calculated for each of the 78 ECG- echo pairs. Regression analyses were performed to assess how much variance in ECG measures was explained by variation in LV dimensions and by demographic variables (age, sex, race).

Results:
ECG and echo measurement correlations were significant and concordant in 41/78 (53%), though many were significant and discordant in 13, (17%) or not correlated in 24 (31%). Of the 6 ECG measures of LV size, 5 correlated in the clinically predicted direction for LV Mass-z and LVEDV-z. While many of the correlations were statistically significant, the correlations were weak (0.05-0.25). R
2
was higher for demographic variables than for echo measures in all pairs, but even with demographic variables included, the overall R
2
was
<
0.17.

Conclusions:
In a large, diverse cohort of healthy children, there was a positive association between echo measures of LV dimension and mass and the most commonly used ECG measures of LVH. However, these correlations were weak and most of the variability in ECG measures was explained by factors other than echo derived mass or volume or measured patient demographic variables. These data question the utility of traditional ECG measurements of LV size as standalone indications for further cardiac evaluation in healthy children.
Abstract 15544: Implication of the Histone Methyltransferase “G9a” in Pulmonary Arterial Hypertension
Authors: awada Charifa , Habbout Karima , Nadeau Valerie , Breuils-Bonnet Sandra , Paulin Roxane , Provencher Steeve , Bonnet Sebastien , BOUCHERAT Olivier
Published: May 2021

Rationale:
Pulmonary arterial hypertension (PAH) is a cardiopulmonary disorder characterized by elevation of pulmonary arterial (PA) pressure and premature death. PA smooth muscle cells (PASMCs) from PAH patients present a cancer-like hyperproliferative and apoptosis-resistant phenotype contributing to remodeling of distal PAs. Although epigenetic alterations contribute to PAH development,

one important challenge is defining which genes are the drivers

. A growing body of literature points to the role of an epigenetic factor called G9a in cancer pathogenesis. Indeed, G9a is a histone methyltransferase overexpressed in many cancers promoting cell proliferation and survival. Given the similarities between PAH and cancer, it is of interest to determine whether G9a is implicated in PAH. We thus hypothesized that
G9a inhibition reduces the pro-proliferative and apoptosis resistance phenotype of PAH-PASMCs.

Methods and Results:
Using Western blot (WB) and immunofluorescence (IF), we showed that G9a is overexpressed in distal PAs and isolated PASMCs from PAH patients (n= 6-14, p<0.01). Similarly, G9a was increased (WB and IF, p<0.05) in two models mimicking the disease; namely the monocrotaline rat and mice exposed to chronic hypoxia. In vitro, we found that pharmacological inhibition of G9a using BIX01294 and UNC0642 reduces PAH-PASMC proliferation (Ki67 and EdU assays, p<0.001) and survival (Annexin V assay p<0.001). Through RNA sequencing analysis conducted in PAH-PASMCs treated or not with BIX01294, we found that upregulated differentially expressed genes (DEGs) were enriched in cholesterol biosynthesis, autophagy-lysosome and ER stress-induced apoptotic pathways. However, downregulated DEGs were involved in cell cycle and fibrosis-related processes. Consistently, inhibition of G9a generates numerous cytoplasmic vacuoles positive for LC3-II and p62 (WB, IF), thus suggesting that the inhibition of G9a induces cell death by altering cholesterol metabolism-dependent autophagy.

Conclusion:
We showed for the first time that G9a is overexpressed in PAH contributing to the pro-proliferative and anti-apoptotic phenotype of PAH-PASMCs. Current experiments aim to determine whether G9a inhibition provides therapeutic benefits in PAH.
Abstract 15547: Sfrp2 Mediates Ipsc to Cardiomyocyte Differentiation via Competing Actions on Wnts
Authors: Hsueh Ying-chang , Hodgkinson Conrad , Pratt Richard E , Dzau Victor J
Published: May 2021

Induced pluripotent stem (iPS) cells provide a novel avenue to investigate how precursors differentiate into cardiomyocytes. In this study we examined our hypothesis that iPS differentiation is regulated by a balance between cardiogenic and inhibitory Wnt proteins. Recently, we have discovered that iPS cells differentiate into cardiomyocytes in response to Sfrp2 (control: 0% cardiomyocytes; Sfrp2 treated: 25% cardiomyocytes. N=3. P<0.01). Since Sfrp2 mediates its effects by binding to Wnt proteins, we hypothesized that Sfrp2 promotes cardiomyocyte differentiation by binding to a Wnt that prevents iPS cells from differentiating into cardiomyocytes. To identify the inhibitory Wnt protein, we studied the effects of Wnt blocking antibodies on iPS and differentiation into cardiomyocytes. We observed that in control iPS cells or iPS cells incubated with a Wnt5 blocking antibody no cardiomyocytes appeared. In contrast, iPS cells incubated with a Wnt3a blocking antibody spontaneously and robustly differentiated into cardiomyocytes (40%, N=5, P<0.001). Co-immunoprecipitation experiments demonstrated that Sfrp2 binds to Wnt3a (N=3, P<0.001). Furthermore, Sfrp2 binding to Wnt3a inhibited b-catenin activation in iPS cells (80% active b-catenin in control cells; 10% active b-catenin in Sfrp2 and Wnt3a blocking antibody treated cells. N=3. P<0.05). To identify the cardiogenic Wnt, we again screened iPS differentiation following incubation with various Wnt blocking antibodies. Through this process, we found that the positive effects of Sfrp2 or Wnt3a blocking antibodies were completely lost when the iPS were co-cultured with Wnt11 blocking antibodies (Wnt3a blocking antibody alone: 40% cardiomyocytes; Wnt3a plus Wnt11 blocking antibody: 0% cardiomyocytes). Interestingly, in iPS cells incubated with Wnt11 blocking antibody, b-catenin was re-activated (control cells: 10% active b-catenin; cells incubated with Wnt11 blocking antibody: 60% active b-catenin. N=3. P<0.05). In summary, iPS cells do not spontaneously differentiate into cardiomyocytes because of opposing effects of Wnt3a and Wnt11. Sfrp2 promotes cardiomyocyte differentiation by binding to Wnt3a, allowing Wnt11 to induce iPS cells to differentiate into cardiomyocytes.
Abstract 15551: Evening Blood Pressure Burden and Cardiac Load: A Sex-specific Association of Nocturia in the Japanese at High-risk of Cardiovascular Disease
Authors: NAGAI Michiaki , Hoshide Satoshi , Kario Kazuomi
Published: May 2021

Introduction:
Earlier epidemiologic studies have reported a significant relationship between hypertension and nocturia. However, the underlying pathophysiology has been unclear.

Hypothesis:
We assessed the hypothesis that blood pressure (BP) burden and cardiac load might be associated with severity of nocturia. In addition, this association was hypothesized to be moderated by sex.

Methods:
In the Japan Morning Surge-Home Blood Pressure Study, measurements of home BP (HBP) at evening (mean 11.2 days) as well as brain natriuretic peptide (BNP) were performed in the 4310 patients with one or more cardiovascular risks (64.9 years old, male 47%). A self-administered questionnaire included items on nocturia was used.

Results:
According to the number of nocturia (no void: n= 2382; one void: n=847; ≥ 2 voids per night: n=1082), significant associations of systolic BP (SBP) at evening (130 vs 130 vs 132 mmHg, p<0.0001) and logBNP (1.20 vs 1.30 vs 1.42, p<0.0001) were observed with nocturia severity. In the multinomial logistic regression analysis adjustment for confounders including age, smoking, total cholesterol, fasting blood glucose, HbA1c and clinic SBP, the use of diuretics (OR: 1.26, 95%CI: 1.06-1.52, p<0.05) was significantly associated with one nocturnal void, while evening SBP (OR: 1.009, 95%CI: 1.003-1.014, p<0.01) and logBNP (1.43, 95%CI: 1.19-1.73, p<0.001) were significantly associated with multiple nocturnal voids. While no significant interaction was found between evening SBP and logBNP for multiple nocturnal voids in the total population (p=0.1), a significant interaction was found between evening SBP and logBNP for multiple nocturnal voids only in females (p<0.05).

Conclusions:
In conclusion, the use of diuretics was a significant indicator of single nocturnal void, while evening SBP and BNP were those of multiple nocturnal voids in the high-risk Japanese population. Specifically, in the females, treatment to reduce BP burden as well as cardiac overload might be important to improve sleep disturbance caused by nocturia.
Abstract 15552: Learning and Innovation Among Interventional Cardiologists, Insights From an International Survey
Authors: Vemmou Evangelia , Nikolakopoulos Ilias , Rangan Bavana V , Xenogiannis Iosif , Karacsonyi Judit , Burke M Nicholas , Croce Kevin J , Bergmark Brian A , Brilakis Emmanouil S
Published: May 2021

Introduction:
The willingness of interventional cardiologists to adopt innovation and implement changes in day-to-day practice has received limited study.

Methods:
Online-based survey on learning and innovation involving 38 questions distributed via email list to interventional cardiologists.

Results:
The survey was distributed to 8,110 e-mails and completed by 621 (7.6% , 92% men, 60% in the 35 to 54-year-old age group). Of the respondents who perform coronary interventions, 45% perform >100 cases of non-complex percutaneous coronary interventions per year and of the respondents who perform structural interventions, 15% perform more than >100 transcatheter aortic valve replacements per year. Most respondents (86%) are highly likely/likely to introduce recently approved equipment in everyday practice and 48% have tried a new coronary guidewire in the past six months (
Figure
). Regarding specific techniques, most (69%) use the double kissing crush technique when treating coronary bifurcations with a 2-stent strategy, followed by T -stenting (60%). Radial access in STEMI cases is always used by 43% of the respondents and 54% always use radial access for coronary angiography. Of those who use femoral access, 32% always use ultrasound guidance and 91% have used a closure device in the last six months. The majority read journals to keep up with current practice and believe that the most effective way to learn is through attendance of workshops/short courses (79%), followed by proctorship (61%). Most of the respondents (69%) are involved in research.

Conclusions:
Interventional cardiologists who participated in the survey are highly likely to adopt innovation in daily clinical practice.
Abstract 15553: The Long-term Outcome Beyond Pulmonary Vein Isolation of Ablation Guided by the Online and Real-time Atrial Fibrillation Imaging System: Extra Mapping Project
Authors: Sakata Kensuke , Okuyama Yusuke , Ozawa Tomoya , Fujii Yusuke , Kato Koichi , Haraguchi Ryo , Inada Shin , Nakazawa Kazuo , Sugimoto Yoshihisa , Yamashiro Kohei , Nakagawa Yoshihisa , Ashihara Takashi
Published: May 2021

Introduction:
Although modulation of atrial fibrillation (AF) drivers and/or substrates has been proposed as one of the effective ablation strategies for non-paroxysmal AF (Non-PAF), previous meta-analyses showed that ablation, targeting complex fractionated atrial electrogram (CFAE) indirectly-reflecting Non-PAF drivers, had no additional benefit for post-pulmonary vein isolation (PVI) Non-PAF. As an alternative ablation strategy for Non-PAF, rotor ablation has been proposed as one of the potentiated ablation strategies for Non-PAF. However, the optimal ablation strategy is still unclear because reliable method detecting AF drivers remain unsettled in clinical practice.

Hypothesis:
Because rotors are known as key mechanisms for Non-PAF, we might open the possibility of Non-PAF control by the real-time visualization of wave dynamics during AF ablation.

Methods:
Consecutive 140 Non-PAF patients were enrolled in this study. The clinically-available online and real-time AF imaging system with high-spatiotemporal density (ExTRa Mapping
TM
) developed by our group was applied in case Non-PAF was remained after PVI. Then, we detected and ablated non-passively-activated areas where rotational activations in the form of meandering rotors and/or multiple wavelets assumed to contain Non-PAF drivers were frequently observed (figure, top). The recurrence rate of Non-PAF or atrial tachycardia (AT) after the ablation was compared to that in patients underwent PVI-alone at our hospital.

Results:
The propensity scores selected each 34 people from ExTRa-strategy group and PVI-alone group (figure, middle). The 24-month freedom ratio from Non-PAF/AT in the matched-ExTRa-strategy group was higher than the matched-PVI-alone group, which was close to significance (p = 0.056) (figure, bottom).

Conclusion:
The ExTRa Mapping-guided ablation for PVI-refractory Non-PAF might be superior to PVI-alone.
Abstract 15559: In-hospital versus Out-of-hospital Cardiac Arrest in Patients Presenting to Cardiac Intensive Care Units: From the Critical Care Cardiology Trials Network (CCCTN) Registry
Authors: CARNICELLI Anthony P , Brown Kelly , Guo Jianping , Kendsersky Payton , Arps Kelly E , Dixson Jeffrey A , Keane Ryan , Berg David D , Bohula Erin A , Harrison Robert W , Granger Christopher B , Van Diepen Sean , Morrow David A , Katz Jason N , Newby L. Kristin
Published: May 2021

Background:
Cardiac arrest (CA) is a common reason for cardiac intensive care unit (CICU) admission and is associated with considerable morbidity, mortality, and resource use.

Aim:
To describe characteristics and outcomes of pts presenting to contemporary CICUs with in-hospital (IH) or out-of-hospital (OH) CA.

Methods:
The Critical Care Cardiology Trials Network (CCCTN) is a multicenter network of tertiary CICUs in North America (n=25). Participating centers contributed data from consecutive admissions during 2-month annual snapshots between 9/2017 and 8/2019 (n=8240). We analyzed characteristics and outcomes of pts with CA by IHCA vs OHCA.

Results:
Of 975 admissions with CA (48.9% OHCA), most were male (64.7%), Caucasian (63.4%) and smokers (60.6%). Acute coronary syndrome (ACS) was present in 30.6% and cardiomyopathy in 21.8%. Shockable rhythm was present in 54.1%, more commonly among those with reduced ejection fraction, ischemic cardiomyopathy, or ACS (p<0.01 for all). Compared with IHCA, patients with OHCA were younger (median age 62 vs 66 years) and had fewer comorbidities including heart failure, atrial fibrillation, valvular disease, pulmonary HTN, and CKD (p<0.01 for all). Pts with OHCA more commonly had shockable rhythms (58.3% vs 50.0%) and were more likely to be comatose at initial assessment (75.7% vs 40.4%); p<0.01 for both. Resource use varied significantly between OHCA and IHCA [
Fig
] and CICU length of stay was longer for pts with OHCA (median 3.4 vs 3.1 days; p=0.049). In-hospital mortality was 41.2% and was higher in OHCA (44.7%) compared with IHCA (38.0%), p=0.03 [
Fig
]. Eventual discharge home or to rehab was more common among pts with IHCA (51.6% vs 49.1% for OHCA; p<0.01).

Conclusion:
Despite advances in pre- and in-hospital care, pts presenting to contemporary CICUs with CA have high in-hospital mortality, with IHCA mortality only modestly lower than in OHCA. A better understanding of patterns may guide new approaches to improve patient outcomes.
Abstract 15560: Induced Pluripotent Stem Cell (iPSC) Derived Smooth Muscle Cells as a Model to Study Vascular Calcification
Authors: Atkins Samantha K , Brouwhuis Romi , Singh Sasha A , Aikawa Masanori , Aikawa Elena
Published: May 2021

Introduction:
Vascular calcification is the top cause of mortality worldwide. Vascular smooth muscle cells (SMCs) are major contributors to vascular calcification. There is an urgent need for a large scale and inexhaustible source of functional SMCs to study mechanisms of cardiovascular calcification. Here, we describe a new platform utilizing iPSCs differentiated towards SMCs that can calcify, to model ectopic calcification and identify mechanisms of SMCs’ contribution in this pathological process.

Methods:
We differentiated human iPSCs towards an induced-SMC (iSMC) phenotype in a 10-day protocol. We verified successful iSMC differentiation through immunofluorescent staining for SMC marker proteins αSMA and MYH11, FACS using CD140b, and proteomics analysis on whole cell lysate at days 0, 3, 5, 7, and 10. A set of 19 canonical SMC proteins were used to generate a Pearson’s correlation over the differentiation time course. After differentiation, we cultured the iSMCs in osteogenic media (OM) for 14 days. Alizarin Red S staining performed on day 14 confirmed the presence of calcification. Three independent experiments were performed for all data analyses.

Results:
Typical SMC morphology with positive staining for αSMA and MYH11 was detected at day 10 by immunofluorescence (Fig 1A). FACS analysis on markers for iPSCs (TRA-1-60), ECs (CD31), and SMCs (CD140b) demonstrated that 93.9% of cells were positive for CD140b after 10 days of differentiation (Fig 1B, C). Time course proteomics showed a strong Pearson’s correlation with of iSMCs with SMC marker proteins (R = 0.89) by day 10 (Figure 1D). Calcification in osteogenic media was observed by day 14 in culture using Alizarin Red S staining (Fig 1E, F), with 4.8-fold higher calcification in OM as compared to normal media (NM).

Conclusions:
Investigated iSMCs have promising future applications in cardiovascular research and may serve as an inexhaustible resource for studying vascular SMC calcification.
Abstract 15561: Incremental Prognostic Value of Biventricular Longitudinal Strain and Hs-tni in Covid-19 Patients
Authors: XIE Mingxing , Sun Wei , zhang yanting , WU CHUN , Xie Yuji , Zhang Li , Taub Cynthia C.
Published: May 2021

Background:
Myocardial strain derived from two-dimensional speckle-tracking echocardiography (2D-STE) has been shown to be more sensitive to detect early ventricular dysfunction than conventional echocardiography. However, the study about the prognostic value of biventricular longitudinal strain in coronavirus disease 2019 (COVID-19) is still scarce.

Aims:
We aimed to evaluate the prognostic value of biventricular longitudinal strain and its combination with high-sensitivity troponin I (hs-TNI) in COVID-19 patients.

Methods:
We enrolled a total of 160 COVID-19 patients who underwent both echocardiogram and hs-TNI testing. The cardiac structure, function and myocardial strain were compared between patients with and without elevated hs-TNI levels. Left ventricular longitudinal strain (LV LS) and right ventricular free wall longitudinal strain (RVFWLS) were determined by 2D-STE.

Results:
Compared with patients with normal hs-TNI levels, patients with elevated hs-TNI levels had diminished LV diastolic function, larger right-heart chamber, higher proportion of pulmonary hypertension, lower LV LS and RVFWLS. During a median follow-up of 60 days, 23 patients died. The multivariant analysis revealed LV LS and RVFWLS [Odd ratio (confidence interval): 1.533 (1.131-2.079);
P
=0.006; 1.267 (1.101-1.794),
P
=0.021, respectively] both were the independent predictors of higher mortality. Further, receiver-operating characteristic analysis revealed that the accuracy for predicting death was greater for the combination of hs-TNI levels with LV LS than separate LV LS (AUC: 0.93 vs 0.77,
P
=0.001), and for the combination of hs-TNI levels with RVFWLS than RVFWLS alone (AUC: 0.92 vs 0.83,
P
=0.041).

Conclusion:
Our study highlights that the combination of ventricular longitudinal strain with hs-TNI can provide a higher accuracy for predicting mortality in COVID-19 patients, which may enhance risk stratification in COVID-19 patients.
Abstract 15575: The Clonal Hematopoiesis Mutation
Jak2
V617F
Aggravates NETosis and Endothelial Injury in Mouse Arteries With Erosion-like Intimas
Authors: Molinaro Roberto , Sellar Rob S , Sausen Grasiele , Vromman Amelie , Folco Eduardo , Sukhova Galina K , Ebert Benjamin , Libby Peter
Published: May 2021

Introduction:
In the current era of intense LDL lowering, superficial erosion may be on the rise as a cause of ACS (25-30%). Experimental data on human atheromata support a role for neutrophils and the formation of neutrophil extracellular traps (NETs) in the pathogenesis of superficial erosion and subsequent thrombosis. The common mutation of
Janus kinase 2
(
Jak2
V617F
) borne by clones of leukocytes derived from bone marrow stem cells sensitizes neutrophils to undergo NETosis and linked NET formation to increased thrombosis.
Jak2
V617F
associates with accelerated atherosclerosis and venous thrombosis in patients with myeloproliferative neoplasms (MPN) and in individuals harboring this mutation but without a demonstrable MPN.

Hypothesis
We hypothesized that i) the
Jak2
V617F
associated with clonal hematopoiesis and increased atherosclerotic and thrombotic risk in humans, predisposes to NETosis and subsequent endothelial injury and thrombosis at sites of flow disturbance in arteries with erosion-like intimas; and ii) the clinically approved Jak-1,2 inhibitor, ruxolitinib (Rux), can preserve endothelial integrity and reduce thrombosis in mice with myeloid
Jak2
V617F
.

Methods:
We generated cohorts of mice harboring
Jak2
V617F
or wild-type
Jak2
. We used a surgical preparation recapitulating features of superficial erosion and assessed endothelial integrity, thrombosis, and NET formation in relation to genotype and
in vivo
Rux treatment.

Results and Conclusions:
Evans blue extravasation following introduction of flow disturbance at sites of erosion-prone intimas showed significant impairment of endothelial barrier in the group of mice bearing the
Jak2
V617F
mutation compared to control (WT) mice (
**
p<0.005). We further observed more thrombosis in mice bearing the
Jak2
V617F
mutation. Immunohistochemical evaluation of the regions of experimental superficial erosion revealed reduced endothelial continuity and increased NET accumulation in
Jak2
V617F
vs. WT mice. Rux treatment mitigated the adverse effects of
Jak2
V617F
on both NET accumulation and endothelial integrity, supporting the translational potential of these observations in individuals with clonal hematopoiesis due to
Jak2
V617F
and acute coronary syndromes.