bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 13392: Impaired Oxygen Uptake Efficiency Slope (OUES) Predicts Mortality in Wild-Type Transthyretin Amyloid Cardiomyopathy (ATTRwt-CM)
Authors: Fattouh Michael , Patel Akash , Gilad Amir , Smerkers Brian , Waheed Anam , Berk John , Connors Lawreen , Sanchorawala Vaishali , Siddiqi Omar , Ruberg Frederick , Balady Gary J , Gopal Deepa M
Published: April 2022

Introduction:
Cardiopulmonary exercise testing (CPET) is a prognostic tool for advanced heart failure. Whether exercise metrics can provide incremental mortality prediction in ATTRwt-CM has not been well-studied.

Hypothesis:
We hypothesize CPET metrics improve mortality prediction in ATTRwt-CM.

Methods:
A retrospective review was conducted in ATTRwt-CM patients evaluated at the BU Amyloidosis Center between 2009-2019 who underwent CPET testing. Baseline demographic, clinical, and mortality data was collected. Continuous and categorical variables were compared using paired t-testing and chi-square testing, respectively. Baseline variable association with mortality was evaluated using logistic regression. Kaplan-Meier curves were used for survival estimation and Hazard ratios (HR) were estimated using Cox proportional hazards regression analysis.

Results:
A total of 136 patients with ATTRwt-CM were analyzed with median follow-up of 4 years (IQR 2.4, 5.6) with 43% deaths (n=59) during follow-up. Differences in baseline characteristics and metrics between individuals with and without mortality are shown in the table. Peak VO
2
, V
E
/VCO
2
, ventilatory threshold, heart rate recovery, and OUES were significantly associated with mortality. Using backwards stepwise regression, only OUES remained significantly associated with mortality among CPET variables. Using multivariable Cox survival analysis (adjusting for age, NYHA, eGFR, LVEF, troponin I, and BNP), OUES remained significantly associated with mortality (HR 0.25, 95% CI 0.08 - 0.77; p=0.02). The addition of OUES to troponin I, BNP, GLS, and eGFR increased the Wald chi-square statistic from 22.5 to 26.5 (p=0.01).

Conclusions:
The addition of OUES in ATTRwt-CM improves mortality prediction when added to current disease staging biomarkers: troponin I, BNP, GLS, and eGFR. This study highlights the incremental strength in outcome prediction using an exercise parameter, OUES, in ATTRwt-CM.
Abstract 13400: STAT3 ASO-Loaded Microbubbles With Pulsed Ultrasound for Enhanced Therapeutic Effect in Head and Neck Tumors
Authors: Ramasamy Thiruganesh , Chen Xucai , Johnson Daniel E , Grandis Jennifer , Villanueva Flordeliza S
Published: April 2022

Introduction:
Signal transducer and activator of transcription 3 (
STAT3
) is an oncogenic transcription factor implicated in carcinogenesis, tumor progression, and drug resistance in many cancers, including head and neck squamous cell carcinoma (
HNSCC
). STAT3 antisense oligonucleotide (
ASO
) specifically targeting the nucleotide sequence of STAT3 has therapeutic promise, but effective delivery remains challenging. We developed microbubble (
MB
) delivery vehicles loaded with STAT3 ASO and hypothesized that compared to intravenous (
i.v.
) delivery, ultrasound-targeted microbubble cavitation (
UTMC
)-mediated ASO delivery confers superior tumor growth inhibition.

Methods:
Lipid MBs loaded with STAT3 ASO (S3MB) or mutant ASO (Mut-MB) were prepared. First, murine squamous carcinoma cells (SCC-7) in contact with MBs were exposed to pulsed ultrasound (1 MHz, 0.5 MPa, 100 μs pulse duration, 1 ms pulse interval) for 10 sec to establish efficacy with respect to cytotoxicity, apoptosis, and gene knockdown. Thereafter, the anti-tumor effect of 3 treatments with STAT3 ASO (10 μg) delivered i.v. or via UTMC x 15 min (
f=
1MHz, 0.7MPa, 100 cycles x 5 every 2 sec) was compared
in vivo
in a murine SCC-7 xenograft model followed up to 17 days.

Results:
S3MB + UTMC conferred more cytoxocitiy, apoptosis, and downregulation of transcripts for STAT3 and its target genes (Bcl-xL and Cyclin D1) compared to Mut-MB + UTMC
in vitro
(p<0.05). In tumor bearing mice, compared to i.v. STAT3 ASO (n=8), Mut-MB+UTMC (n=5) or no treatment (n=8), S3MB + UTMC (n=9) significantly attenuated tumor burden, prolonged doubling time, and improved survival (p<0.05). While i.v. STAT3 ASO had no effect on tumor expression of STAT3, Bcl-x, and cyclin D1 at the transcript and protein levels, its delivery via UTMC significantly reduced tumor expression of these genes (p<0.01).

Conclusion:
At a dose of 10 μg, STAT3 ASO significantly inhibited murine HNSCC tumor growth and downregulated STAT3 and its target genes when delivered via UTMC, compared with intravenous administration alone. Our platform offers a promising imaged-guided, targeted delivery strategy for nucleotide-based therapeutics in cancer applications.
Abstract 13406: Psychosocial Stress, Life Satisfaction, And Hypertension: A Mediation Analysis
Authors: Zhang Liying , Dailey Rhonda , Brook Robert D , Levy Phillip
Published: April 2022

Background:
Disparities in hypertension control remain an important issue in public health. Evidence indicates that psychosocial factors are associated with onset and trajectory of hypertension. However, mediators of the association between psychosocial factors and hypertension are understudied. The objective of this study is to explore the mediating effect of life satisfaction on the link between psychosocial stress and hypertension.

Method:
This is a secondary analysis of data from the Panel Study of Income Dynamics (PSID) with the 2019 wave of 26,084 adults. Hypertension was assessed with the question: “Has a doctor or other health professional ever told you that you had high blood pressure or hypertension?” Psychosocial stress was assessed by using the K-6 Non-Specific Psychological Distress Scale developed by Dr. Ronald Kessler with 6 items. Participants were asked to rate their life satisfaction with a Likert-type question. Multiple logistic regression and mediation analysis were performed.

Results:
The mean age of this sample was 45 years and 27.5% were female. Results showed that participants with a higher level of psychosocial stress had a lower proportion of life satisfaction (26.3% vs. 70.7%, p<0.01) and a higher proportion of hypertension (42.5% vs. 28.6%, p<0.01) compared to those with a lower level of psychosocial stress. Participants who rated their life satisfied had a lower proportion of hypertension (27.4% vs. 32.9%, p<0.01) compared to those who rated their life not satisfied. After controlling for covariates, regression results showed that psychosocial stress and life satisfaction were associated with hypertension independently. The indirect effect of psychosocial stress on hypertension through life satisfaction was significant (p<0.01).

Conclusions:
Psychosocial stress was significantly associated with hypertension and this effect was partially mediated by life satisfaction. Interventions to decrease psychosocial stress that also emphasize improvements in life satisfaction may be needed to reduce the impact on hypertension.
Abstract 13414: Studying Sonoporation-Induced Drug Payload Penetration Beyond the Blood-Brain Barrier Using Multi-Cellular Human Brain Spheroids
Authors: Paranjape Anurag N , D’Aiuto Leonardo , Zheng Wenxiao , Ramasamy Thiruganesh , Chen Xucai , Villanueva Flordeliza S
Published: April 2022

Introduction:
Ultrasound-targeted microbubble cavitation (
UTMC
) facilitates delivery of cell-impermeant drugs across the endothelial barrier, such as the blood brain barrier (
BBB
)
.
Using cultured endothelial cell (
EC
) monolayers, we reported that UTMC causes sonoporation and inter-endothelial gaps, which may mediate vascular hyperpermeability, although mechanisms are incompletely understood. Further, the effects of UTMC on extravascular cells, and extent of payload penetration are unknown, as the monolayer does not recapitulate the 3D multicellular environment. Here, we established a 3D multicellular human brain spheroid model to study UTMC bioeffects and underlying mechanisms.

Methods:
Spheroids were generated using neurons and astrocytes derived from human iPSCs, primary human brain- microglia, ECs and pericytes, and placed in a water tank with lipid microbubbles (
MBs
). Ultrasound (1 MHz frequency, 250-500 kPa peak negative pressures, 10 μs pulse duration, 10 ms pulse interval) was delivered for 20 s and spheroids were immediately collected. Immunostaining was used to localize cell types; propidium iodide (PI) uptake to mark sonoporation; calcein-AM and sytox to detect cell viability; and Texas red dextran (TRD) (10 kDa) to quantify permeability, using confocal microscopy.

Results:
Immunostaining showed ECs and pericytes at the spheroid periphery, with high expression of membranous ZO-1. BBB functionality was confirmed with histamine treatment, which increased permeability to TRD (28.8% increase in TRD mean intensity,
p
=0.0015). Interestingly, PI uptake (sonoporation) occurred in cells beyond the BBB. TRD penetrated up to ~100 μm beyond the BBB upon UTMC (12.2% increase). Inhibition of endothelial nitric oxide synthase with L-NAME reduced UTMC-induced TRD penetration (19% decrease,
p
=0.0458).

Conclusions:
In this novel 3D human brain spheroid model with intact BBB, UTMC caused nitric-oxide dependent BBB breach. Moreover, this is the first report of UTMC causing “remote” sonoporation of cells not in direct contact with MBs, which bears further study. Our model allows the study of mechanisms mediating UTMC efficacy for targeted delivery of drugs across the endothelial barrier, which should facilitate its clinical translation.
Abstract 13419: Novel Methods to Quantify Limitation of Right Ventricular Exercise Reserve in Pulmonary Hypertension: Afterload vs Ventricular Interdependency
Authors: Raza Farhan , Kozitza Callyn , Lechuga Christopher G , Merchant Mohammed , Korcarz Claudia E , Philip Corrado , Seiter Daniel , Reeder Scott , Eldridge Marlowe , Wieben Oliver , Chesler Naomi
Published: April 2022

Introduction:
In this study, we report novel methods to investigate impact of pulmonary arterial (PA) afterload with impedance and ventricular interdependency with myocardial strain on right ventricular (RV) reserve with exercise and RV:PA coupling.

Hypothesis:
In pre-capillary pulmonary hypertension (PH), RV is conditioned to a higher contractility (end-systolic elastance: Ees) due to increased impedance and RV reserve is independent of left ventricle. However, in isolated post-capillary PH (Ipc-PH), RV is not conditioned due to lower impedance, yet contractility reserve is poor due to lower interventricular septal strain.

Methods:
In 4 subjects (Table 1), we performed invasive cardiopulmonary exercise tests with simultaneous echocardiogram for impedance quantification with spectral analysis, followed by real-time RV pressure volume loops (Figure 1A: data recorded at rest and every 25 watts till peak-exercise). Cardiac MRI was performed within 24-hours to assess myocardial function, strain, and 4D flow at rest and exercise in the bore.

Results:
The augmentation of RV contractility (Ees) with exercise is poor in Ipc-PH, despite an afterload (Ea) similar to the normal subject. The left ventricular septal strain is reduced in Ipc-PH which may indicate enhanced interventricular dependency. Due to increased afterload in pre-capillary PH, RV is conditioned to higher contractility (Ees), and RV reserve is possibly independent of the left ventricle.

Conclusion:
Our novel methods provide an opportunity to investigate mechanisms of poor RV reserve with exercise in different phenotypes of PH. We will further validate these preliminary findings in our ongoing studies.
Abstract 13427: Identification of Patients Who Can Safely Undergo Same Day Discharge Following Atrial Fibrillation Ablation: Lessons Learned in the COVID-19 Era
Authors: Milstein Nicolle S , Saberito Matthew T , Musat Dan L , Bhatt Advay G , Habibi Mohammadali , Preminger Mark , Sichrovsky Tina C , Mittal Suneet
Published: April 2022

Background:
Historically, pts have been admitted for overnight observation following atrial fibrillation (AF) ablation. The COVID-19 pandemic ushered the need to consider same day discharge (SDD). It remains unclear how to identify pts who can safely undergo SDD.

Objective:
To evaluate acute (within 4 hrs) and subacute (within 24 hrs) safety of SDD post AF ablation; we also sought to identify predictors of safe discharge.

Methods:
All pts undergoing AF ablation at our center following the end of the COVID imposed lockdown were enrolled. In each pt, ICE guided single transseptal puncture using the VersaCross® (Baylis) system was performed. Following ablation, protamine was not administered; all femoral venous access sites were closed with Vascade™ (Cardiva Medical) closure devices. Pts ambulated after 2 hrs of bedrest. Pts who had SDD were compared to those who stayed for overnight observation.

Results:
The cohort included 226 pts (65 ± 10 yrs, 157 [69%] male, 118 [52%] PAF, CHA
2
DS
2
-VASc 2.4 ± 1.7). Cryo PVI was performed in 193 (85%) pts; 34 (15%) pts had a redo procedure. SDD was attempted in 126 pts and successfully accomplished in 115 (91%) pts at 251
+
72 minutes from procedure end. The most common reason for failed SDD attempt was access site oozing necessitating additional bedrest. No SDD pt had a major complication. Overnight observation was performed in 100 (44%) pts, most commonly due to physician/pt preference. Compared to pts who had SDD, these pts were older and more likely to have heart failure and history of TIA/stroke. Oozing within the first 4 hrs was observed at a similar rate to SDD pts. A minor complication was seen in 1 pt each in SDD and overnight stay group between 4 and 24 hrs of ablation (Figure).

Conclusions:
Our study shows that when attempted, SDD after AF ablation can be accomplished in >90% of pts. Venous access site oozing was the greatest hinderance to pts going home. However, if pts had no issue 4 hrs after AF ablation, they had an uneventful course over the next 24 hrs.
Abstract 13454: Cardiac Abnormalities in a Large Student Athletes Screening Cohort in Central Texas
Authors: Ahmed Yousuf , Seghers Matthew , Garcia Michelle , Fenrich Arnold L , Rodgers George , Molossi Silvana M
Published: April 2022

Introduction:
Sudden cardiac death (SCD) in the young is a rare but devastating event. Pre-participation evaluation is required prior to competitive sports. The Texas Adolescent Athlete Heart Screening Registry (TAAHSR) performs screening events including history, ECG and limited echocardiogram (ECHO).

Hypothesis:
Cardiac abnormalities are identified in athlete screening and challenges exist in long-term follow up.

Methods:
The TAAHSR database of 4309 participants between 2013-2020 was analyzed and follow up data obtained from phone and electronic medical records. Screening results were classified as: I - no abnormality (abnl) identified, II - abnl identified and further evaluation but no activity restriction recommended, level III - abnl identified and further evaluation with activity restriction recommended if concern for SCD.

Results:
Of 4309 participants, 218 (5%) screened positive on either ECG, ECHO, or both. ECG abnl were seen in 117/4309 (2.7%) level II and 23/4309 level III (0.5%). ECHO abnl were seen in 73/4309 (1.7%) level II and 13/4307 (0.3%) level III. The most frequent abnl in 218 positive screenings included: ECG - right ventricular hypertrophy (27, 12%), right bundle branch block (26, 12%), T-wave abnormalities (23, 10%), left ventricular hypertrophy (22, 10%), left axis deviation (17, 8%), Wolff-Parkinson-White (8, 4%); ECHO - bicuspid aortic valve (15, 7%), mitral valve prolapse (9, 4%), increased left ventricular trabeculations (9, 4%). The most frequent positive history in the cohort (218) was family history of heart disease (56, 25%), racing or skipped beats (30, 14%), chest pain after exercise (28, 13%), family history of SCD before age 50 (21, 10%). Follow up data was obtained, to date, in 130/218 (60%) positive screening participants and 72/130 (55%) had the suspected diagnosis confirmed. Of 130, 42 (32%) were reached and are alive at median follow up of 5.3 years.

Conclusions:
Our data shows 3.2% ECG and 2% ECHO positive screening for suspected cardiovascular abnl. Screening results may improve with better utilization of ECG criteria in athletes and lower referral based on ECHO findings that may represent normal pattern in certain populations. Follow up remains a challenge to determine long term outcomes of athlete screening.
Abstract 13459: Human iPS-Derived Pre-Epicardial Cells Direct Cardiomyocyte Aggregation Expansion and Organization
in vitro
Authors: Guyette Jacques P , Tan Jun Jie , Ott Harald C
Published: April 2022

During heart maturation, epicardial-derived cells emanating from the pro-epicardial organ envelope the developing heart, then integrate within the myocardium and undergo epithelial-mesenchymal transition (EMT) to become fibroblasts, smooth muscle cells, and endothelial cells that enable several processes of healthy heart morphogenesis (i.e., ventricular thickening, compaction, and angiogenesis). Directed cardiac differentiation of human induced-pluripotent stem cells (hiPSCs) holds great potential for generating several cardiovascular cell types, which can theoretically be combined to model cardiac development more completely and engineer sophisticated myocardial grafts. Here, we show that differentiating hiPSC-derived lateral plate mesoderm (LPM) with BMP4, RA and VEGF (BVR) for 96 hours can generate a premature form of epicardial cells (termed pre-epicardial cells, PECs) with high efficiency (86.8 ± 4.1% WT1
+
by FACS), that also show significant increases in
WT1, TBX18, SEMA3D
,
TBX5, BNC,
and
SCX
transcript expression within 7 days. This protocol was successfully reproduced in three commercial lines of hiPSCs. BVR stimulation after Wnt inhibition of LPM demonstrated efficient co-differentiation and spatial organization of PECs and cardiomyocytes (CMs) in a single 2D culture. Co-culture consolidated CMs into dense aggregates, which then formed a connected beating syncytium with significantly enhanced contractility (0.029 ± 0.002 mN/mm
2
; p<0.05 vs. CMs-alone and co-culture controls), improved calcium handling (i.e. amplitude, upstroke, and decay), sarcomere length (1.82 ± 0.02 μm vs. 1.72 ± 0.03 μm, p=0.00264) and mitochondrial density (79.4 ± 3% vs. 54.9 ± 6%, p=0.0029). Co-cultured PECs demonstrated enhanced maturity to epicardial cells with significant upregulation of
UPK1B, ITGA4,
and
ALDH1A2
transcript expressions. Our study also demonstrated that PECs secrete IGF2 and stimulate CM proliferation in co-culture (37.2 ± 2.1% vs. 28.1 ± 1%, p=0.016). These characteristics suggest PECs could play a key role in enhancing cell-cell signaling and tissue organization, which may help to recapitulate important aspects of cardiac morphogenesis
in vitro
and advance the maturation of bioengineered cardiac constructs.
Abstract 13468: Single-Cell Driven Drug Repositioning Approach Identifies a New Anti-Atherosclerotic Compound Targeting Myeloid Cells
Authors: Amadori Letizia , Calcagno Claudia , Fernandez Dawn M , Koplev Simon , Fernandez Nicolas F , Kaur Ravneet , Shamailova Roza , Chong Peik Sean , Sajja Swathy , Naidu Sonum , Ghotbi Adam , Soler Raphael , Hill Christopher , Fayad Zahi A , Ma'ayan Avi , Giannarelli Chiara
Published: April 2022

Introduction:
Inflammation is a key driver of atherosclerosis. The identification of new treatments and strategies targeting the specific inflammatory signaling that persists in optimally treated atherosclerotic patients remain an unmet clinical need.

Hypothesis:
The integration of time-of-flight mass cytometry (CyTOF), gene expression analysis, and drug repositioning computational approaches applied to pre-clinical validation in models of the disease using non-invasive imaging will help to identify drugs tailored to residual inflammatory signaling in patients with atherosclerosis.

Methods:
We developed a new systems biology pipeline to identify new therapeutic/indication pair that combines CyTOF and RNA sequencing (RNA-seq) data analysis of clinical samples from patients with carotid and coronary artery disease (CVD) (
Fig.
1A
). This approach allowed the identification of new uses for existing compounds. The predicted anti-atherosclerotic effect was validated in ApoE-/- mice and in a rabbit model of atherosclerosis using
18
F-Fluorodeoxyglucose (FDG) PET-MRI.

Results:
We found a specific inflammatory signature in CD14
+
monocytes stimulated with CVD plasma that was used to identify 50 small molecules predicted to reverse this signature. CyTOF screening of the top eight candidate compounds showed that Saracatinib—a phase 2a-ready Src/Abl inhibitor—blunted the inflammatory response found in CD14
+
monocytes (
Fig.
1B
). The anti-atherosclerotic efficacy of Saracatinib was confirmed in ApoE-/- mice fed a high fat diet (
Fig.1C
). In the atherosclerotic rabbit model, Saracatinib reduced plaque inflammation measured as reduction of
18
F-FDG uptake by PET-MRI (
Fig. 1D
).

Conclusions:
These data support the use of our integrated systems biology pipeline as a powerful approach to identify new immune signature specific to patients with atherosclerosis that can be leveraged to identify new indications for existing drugs to treat cardiovascular disease.
Abstract 13476: ROR2 Deficiency is Associated With Endothelial Dysfunction and Reduced Angiogenesis in Pulmonary Arterial Hypertension
Authors: Chakraborty Ananya , Nathan Abinaya , Agarwal Stuti , Orcholski Mark , Yuan Ke , Bonnet Sandra , Bonnet Sebastien , Dejesus Perez Vinicio A
Published: April 2022

Introduction:
Pulmonary arterial hypertension (PAH) is characterized by endothelial dysfunction and progressive loss of lung microvessels. Our group has shown that Wnt pathways are critical for pulmonary angiogenesis but the role of the Wnt/planar cell polarity specific receptor ROR2 in lung endothelial angiogenic responses is unknown.

Hypothesis:
We hypothesized that ROR2 is required for proper angiogenic responses in pulmonary microvascular endothelial cells (PMVECs) and its loss contributes to endothelial dysfunction in PAH.

Methods and Results:
Analysis of PAH lung tissues demonstrated reduced ROR2 expression within vascular lesions and in explanted PMVECs. ROR2 deficiency was associated with reduced proliferation and tube formation in response to VEGF-A, a major inducer of angiogenesis. We found that ROR2 promotes VEGF receptor 2 activation via direct phosphorylation of cytoplasmic residues (Y1175/Y951) and that restoring ROR2 expression in PAH PMVECs led to improved angiogenic responses. Besides angiogenic sprouting, we found that ROR2 is required for lung endothelial barrier formation by promoting the assembly of mature focal adhesions and adherens junctions through activation of Src and focal adhesion kinase (FAK). Compared to wild-type controls, endothelial-specific ROR2 knockout (ROR2 ECKO) mice demonstrated more severe hemodynamics, small vessel loss, and muscularization in chronic hypoxia. Moreover, ROR2 ECKO demonstrated severe RV dysfunction associated with reduced capillary density. We validated these findings in samples of decompensated RV tissue from PAH patients, monocrotaline, and Sugen-hypoxia rats which also demonstrated a significant reduction of ROR2 expression that correlated with RV capillary loss.

Conclusion:
ROR2 plays a protective role in the pulmonary and RV circulations and its loss prevents vessel repair in PAH. Targeting ROR2 could promote recovery of small vessel loss and RV adaptation in PAH.
Abstract 13530: Epi+Gen CHD: A More Sensitive and Cost-Effective Tool to Assess Risk and Monitor Treatment Response for Coronary Heart Disease
Authors: Dogan Meesha , Philibert Willem , Jung Younsoo , Dogan Tim , Frisvold David , Andersen Allan , Hoffman Eric , Philibert Robert
Published: April 2022

Coronary heart disease (CHD) is preventable, but current lipid-based risk assessment tools such as The Framingham Risk Score (FRS) and ASCVD Pooled Cohort Equation (PCE) have limitations. Using DNA-based genetic and epigenetic biomarkers, we have developed a more sensitive and cost-effective incident CHD risk assessment tool, Epi+Gen CHD, that can provide actionable insights and monitor treatment response. This test can be administered remotely via telemedicine using at-home sampling, or in a clinical setting. Epi+Gen CHD was developed and validated using machine learning techniques and datasets from the Framingham Heart Study (FHS) and Intermountain Healthcare (IM). It incorporates five SNPs and three methylation markers for predicting 3-year incident CHD. It was more sensitive than FRS and PCE and had high generalizability across cohorts with sensitivity/specificity of 79/75% in the FHS test set and 75/72% in the IM set. In contrast, the sensitivity/specificity was 15/93% in FHS and 31/89% in IM for FRS, and sensitivity/specificity was 41/74% in FHS and 69/55% in IM for the PCE. To assess cost effectiveness, we conducted cost-utility analyses of Epi+Gen CHD. As compared to the PCE, we found that the use of Epi+Gen CHD was associated with both better survival and highly competitive negative incremental cost-effective ratios (cost savings) ranging from -$42,000 to -$-8,000 per quality-adjusted life year with and without accounting for a secondary test. Finally, to understand if the epigenetic biomarkers in Epi+Gen CHD could be leveraged to monitor treatment response, we performed a proof-of-concept study that assessed the three Epi+Gen CHD methylation sites in 39 subjects before and after 3 months of biochemically verified smoking cessation, then analyzed the relationship between change in methylation at each of the sites to the change in smoking intensity (cg05575921 methylation). We showed that in those who quit smoking, methylation change at one Epi+Gen CHD site (cg00300879) was significantly associated with change in smoking intensity (p < 0.04). We conclude that Epi+Gen CHD can identify patients at risk for CHD, save more lives, reduce more healthcare spending and guide prevention interventions better than current methods.
Abstract 13535: Predictors of Hemodynamic Changes Between Supine and Upright Measurements in Patients With Heart Failure With Preserved Ejection Fraction versus Controls
Authors: Christ Anastasia M , Bhat Rohan , Schoenike Mark , Brooks Liana , Farrell Robyn , Lewis Gregory
Published: April 2022

Introduction:
A resting supine pulmonary capillary wedge pressure (rsPCWP) of ≥ 15 mmHg measured by right heart catheterization is considered the hemodynamic “gold standard” diagnostic criteria for heart failure with preserved ejection fraction (HFpEF). However, right heart catheterization is typically performed as a one-time measurement in patients in the supine position. In this study we sought to define the degree to which PCWP changes upon assuming upright posture in HFpEF vs. controls and determinants of postural changes in PCWP.

Hypothesis:
Patients with elevated rsPCWP will experience a greater fall in PCWP upon assuming upright posture compared to controls and the degree of reduction will be proportionate to BMI.

Methods:
We performed supine right heart catheterization as well as seated upright hemodynamic measurements in consecutive patients referred to a single center for evaluation of exertional dyspnea. Patients with HFpEF as defined by symptoms and rsPCWP≥15mmHg were compared to controls with normal resting hemodynamics and normal exercise capacity. αPCWP was defined as rsPCWP - upright PCWP. Multivariate linear regression was performed with log transformation of non-normal data.

Results:
In 209 patients with HFpEF (age 61
+
14, 52% female, BMI 32
+
7) the mean αPCWP was 11.0+4.5 mmHg compared to 3.7mmHg in the control cohort (n=46, age 56
+
18, 57% female, BMI 26.9
+
4, p<0.001). BMI, but not age or sex were associated with αPCWP in HFpEF. After further adjustment for resting PCWP and blood pressure, BMI remained directly related to αPCWP in the HFpEF cohort (p<0.001). NTproBNP levels were significantly related to upright but not supine PCWP in HFpEF.

Conclusion:
In individuals who meet resting hemodynamic criteria for HFpEF, changes in PCWP with upright positioning are highly variable and change proportionate to BMI.
Abstract 13539: CT-Derived Fractional Flow Reserve in Patients With Non-ST Elevation Myocardial Infarction
Authors: Palomo Andres P , O'Connell Thomas F , Tariq Rehan , Gallagher Michael J , Safian Robert D , Chinnaiyan Kavitha M
Published: April 2022

Introduction:
In patients with non-ST Elevation Myocardial Infarction (NSTEMI), coronary CTA has high diagnostic accuracy to diagnose obstructive coronary artery disease (CAD). The value of CT-derived fractional flow reserve (FFRCT) in NSTEMI patients is unclear.

Hypothesis:
In acute chest pain (ACP) patients diagnosed with an NSTEMI, FFRCT is feasible, safe and adjudicates the need for immediate revascularization.

Methods:
In ACP patients with NSTEMI and no prior coronary artery disease, those undergoing coronary CTA with FFRCT were compared to those having CTA alone for the composite major adverse cardiac event (MACE) endpoint of death, nonfatal myocardial infarction, unplanned percutaneous (PCI) or surgical (CABG) revascularization over 2 years. NSTEMI was defined as peak troponin I levels ≥ 0.04 ng/mL. FFRCT ≤ 0.80 was considered positive for hemodynamically significant stenosis.

Results:
From September 2015 to July 2018, 276 ACP patients with NSTEMI (mean age 59 years, 45% female) underwent CTA of which 35 (13%) had FFRCT (14 negative, 21 positive). Of the total, 126 (45.6%) had normal coronaries and 11 (4.0%) were uninterpretable. FFRCT patients were older (p<0.001) with no difference in diabetes (14.3% vs. 14.1%, p=1.0), hypertension (57.1% vs. 49.4%, p=0.391), hyperlipidemia (34.3% vs. 28.2%, p=0.460) and mean troponin I levels (0.49 ± 0.9 ng/mL vs. 1.10 ± 4.58 ng/mL, p = 0.061). All FFRCT patients had >25% stenosis on CTA (100% vs. 42%, p<0.001). Among patients with comparable stenosis on CTA, FFRCT and CTA had equivalent MACE (5.7% vs. 18.5%, p=0.137), with no difference between FFRCT negative and positive patients (Table 1).

Conclusions:
In this small study, FFRCT did not add incremental value to CTA in patients with NSTEMI across similar stenosis categories with respect to MACE. Larger prospective studies are needed to examine FFRCT in NSTEMI.
Abstract 13543: Impaired Stroke Volume Response During Exercise in Patients With Heart Failure With Preserved Ejection Fraction (HFpEF): The Role of Dynamic Starling Mechanisms
Authors: Hughes Seamus B , Wakeham Denis J , Macnamara James P , Balmain Bryce , Hearon Christopher , Babb Tony , Levine Benjamin D , Sarma Satyam
Published: April 2022

Introduction:
Impaired stroke volume (SV) response during exercise is common in HFpEF. The regulation of SV during low intensity exercise is dependent on end-diastolic volume (EDV) reserve from a compliant left ventricle (LV). The Dynamic Starling Mechanism (DSM) quantifies beat-by-beat modulation of SV by respiratory-mediated changes in LV filling pressure and provides insight into the relationship between changes in LV compliance and SV response during exercise. We hypothesized low SV reserve during exercise would track with greater impairments in DSM gain in HFpEF patients.

Methods:
11 HFpEF patients (68 ± 6 years; 7 females) were studied at rest and during 20 Watts of upright cycling and separated into higher or lower SV reserve (direct Fick) groups based on median SV response (> vs ≤ 20% increase). DSM was quantified by transfer function (input/output frequency) analyses of beat-by-beat changes in pulmonary artery diastolic pressure (PAD, right heart catheterization) and SV (modelflow from radial arterial line waveform). Due to the small group size, magnitude of differences (i.e. effect size) between conditions and groups is assessed via Hedges’
g
.

Results:
HFpEF patients with low SV reserve had blunted increases in SV compared to higher SV group patients (Δ 2 vs 31 ml,
g
= -2.0; Table). Compared to higher SV reserve, the lower SV reserve group exhibited a moderately greater increase in the power spectral density (PSD) of PAD (
g
= 0.4) and decrease in PSD-SV (
g
= 0.5) from rest to 20W. While both groups decreased DSM gain from rest to exercise, the lower SV reserve group had a greater decline (Δ -1.37 vs -0.61 ml/mmHg,
g
= -1.2).

Conclusion:
Lower SV reserve in patients with HFpEF is associated with impaired DSM gain during exercise. The lower gain was a function of increases in PAD PSD and decreases in SV PSD suggesting lower LV compliance and lower EDV reserve during exercise. Impaired DSM may explain low SV response and contribute to exercise limitations in patients with HFpEF.
Abstract 13546: Putative Titin Mutations Associated With Both Long QT Syndrome and Left Ventricular Noncompaction
Authors: Greiner Alexander M , Freese Margaret , Kringlen Gabriel , Powers Edward M , Gutmann Rebecca A , London Barry
Published: April 2022

Introduction:
Inherited long QT Syndrome (LQTS) is characterized by prolonged QTc intervals on electrocardiogram (EKG), ventricular arrhythmias and sudden death (SCD), and is caused by mutations in ion channel or ion-channel related genes. Inherited forms of dilated cardiomyopathy (DCM) and left ventricular noncompaction (LVNC), on the other hand, are caused by mutations in sarcomeric and structural genes including titin.

Methods:
Two unrelated families with histories of SCD presented to us for clinical evaluation of LQTS. Clinical genetic testing covering arrhythmia and cardiomyopathy genes was performed on each proband, with carrier testing on other family members.

Results (Figure):
The proband of family 1 had a strong family history of SCD, carried the clinical diagnosis of LQTS treated with propranolol, and had normal cardiac function by echocardiography. Following chemotherapy with adriamycin for breast cancer, evaluation showed a QTc of 514 ms on EKG, non-sustained VT on Holter, and LVNC with an LVEF=43% on cardiac MRI (cMRI). Genetic testing identified a likely pathogenic nonsense
TTN
variant (p.W18202*) along with a benign
TTN
polymorphism (p.E689K). Her clinically normal daughter did not carry the p.W18202* variant. The proband of family 2 had a strong family history of LQTS and SCD and was diagnosed with LQTS in her 20s after her mother suffered a cardiac arrest. Evaluation showed a QTc of 500 ms on EKG and biventricular LVNC with an LVEF=48% on cMRI. Genetic testing identified a likely pathogenic frameshift
TTN
variant (p.E18038Rfs*47). Three of her children carried the variant and had borderline or prolonged QTc intervals; one had hypertrabeculation on cMRI.

Conclusion:
We have identified two truncating
TTN
variants in close proximity to each other in unrelated families with overlapping LQTS/LVNC/DCM syndromes. Mutations in
TTN
may play a previously unappreciated role in the pathogenesis of inherited arrhythmia syndromes.
Abstract 13547: Secondary Prevention of Rheumatic Heart Disease in Ethiopia
Authors: Belay Wubishet , Dessie Azene , Ali Hayat , Gedlu Etsegenet , Walle Abinet M , Buser Abdulkadir , Tigabu Zemene , Aliyu Muktar H , Soslow Jonathan
Published: April 2022

Introduction:
Acute rheumatic fever (ARF) and rheumatic heart disease (RHD) are significant causes of morbidity and mortality. Ethiopia has a high RHD prevalence but has no national strategic guidelines for preventing RHD and no data on the status of secondary prevention in children with RHD. Generating local information is essential to designing effective prevention and control strategies. This study describes the status of secondary RHD prevention in Ethiopian children.

Methods:
A multicenter, cross-sectional study was performed in children aged 5-17 years with an echocardiogram-based RHD diagnosis. Participants with congenital heart disease and a recent RHD diagnosis (<1 year) were excluded. Good adherence was defined as at least 80% completion of intramuscular benzathine penicillin (BPG) or oral Amoxicillin within the previous year. The primary outcome measure was adherence to prophylaxis, expressed as a proportion. Covariates included socio-demographics, type and severity of RHD, and ARF recurrence. Chi-square test and Student’s t-test were used to assess differences. Multivariate logistic regression was performed.

Results:
We included 337 participants with a mean age (±standard deviation) of 12.9±2.6 years. The majority were females (54%) and 73% had severe aortic/mitral disease. BPG (80%) and Amoxicillin (20%) were the prophylaxis of choice. Predictors of good adherence were female sex (P=0.04), use of BPG (0.03), and shorter mean duration of prophylaxis in months (48.5±31.5 vs. 60.7±33, P<0.008). Running out of medicines (35%), interrupted follow-up (27%), and the COVID pandemic (26%) were the three most common reasons for missing prophylaxis. Recurrence of ARF was higher in participants on Amoxicillin (40% vs. 16%, P<0.001) and in those with poor adherence (36.8% vs. 17.9%, P=0.005). Type and duration of prophylaxis (OR 0.5,
P
=0.02; OR=1.1,
P
=0.04, respectively), and sex (OR=1.9,
P
=0.03) were independent predictors of poor adherence.

Conclusion:
Poor adherence is prevalent in Ethiopian children with RHD. Amoxicillin is a suboptimal option for prophylaxis associated with lower adherence and a higher rate of ARF recurrence.
Abstract 13548: Ventricular Tachycardia: National Trends Among Young: A Public Health Alert
Authors: Patel Harsh P , Thakkar Samarthkumar J , Munshi Rezwan , Faisaluddin Mohammed , Kumar Ashish , Kansara Tikal , Ganatra Sarju , Rao Mohan , Desimone Christopher V , Deshmukh Abhishek , Dani Sourbha
Published: April 2022

Introduction:
In the last two decades, risk factors, prevalence, and mortality due to coronary artery disease in young adults is on the rise.

Hypothesis:
Assess the prevalence, trends, and economic burden of ventricular tachycardia (VT) in young adults (18-44 years).

Methods:
The Nationwide Inpatient Sample was explored for hospitalizations with VT in patients (Age 19-44) between 2005-2018 and divided among 3 groups of the quadrennial period using validated ICD-9 and ICD-10 CM codes. The Pearson chi-square test and Student’s t-test were used for categorical and continuous variables, respectively. We assessed the temporal trends of mortality in VT as well as trends of VT stratified by age, sex, and race by the linear-by-linear association test (Figure 1).

Results:
Out of 5,156,326 patients were admitted with VT between 2005-2018, 309,636 were in young adults. Among them, 102,433 were admitted between 2005-2009 (mean age 36.1±6.99; 61% male, 58.5% white), 109,591 between 2010-2014 (mean age 35.5±7.16; 59% male, 54.2% white), and 97,495 between 2015-2018 (mean age 35.4±7.00; 60% male, 52.3% white) (p<0.0001). In the young adults with VT, all-cause mortality was 7.37% from 2005-2009, 7.85% from 2010-2014 (6.5% relative increase from 2005-2009), and 8.98% from 2015-2018 (relative increase of 14.4% from 2010-2014) (p<0.0001). Inflation adjusted cost increased over the years [$12,177 in 2005-2009; $13,249 in 2010-2014; $15,807 in 2015-2018; p<0.0001)].

Conclusions:
The prevalence of VT in young individuals is rising. VT-related mortality and healthcare utilization costs are on the rise in the study period. VT burden and poor outcomes were notable for Black males. Further studies are required for targeted screening and preventative measures in young adults.
Abstract 13551: RhoA Mediates Pressure-Induced Endothelial Hyperpermeability
Authors: Chignalia Andreia Z , Carvalho-de-Souza Joao , Zemskov Evgeny , Black Stephen M
Published: April 2022

Pulmonary edema is a severe complication of heart failure. It is often caused by the abrupt increase in lung pulmonary capillary pressure that leads to endothelial barrier instability and disruption. The mechanisms whereby high pressure causes pulmonary edema is unresolved. However, eNOS uncoupling and downstream protein nitration may play a role. We have previously shown that eNOS uncoupling, leading to RhoA activation, is key to the development of pulmonary edema in a model of hypertensive heart failure. Herein, we sought to determine if RhoA activation plays a role in pressure-induced pulmonary edema and the molecular mechanisms that govern this process. Human lung microvascular endothelial cells (HLMEC) were exposed to 0cm (control) or 30cm (high pressure) H
2
O pressure for 5 to 60 minutes. Phosphorylation of eNOS at T495 and PKCα activation were assessed by Western blot, RhoA activation and nitration was assessed by ELISA and dot blot assays and endothelial barrier stability was assessed by VE-cadherin staining. The effects of pressure on barrier function were assessed by transendothelial electrical resistance (TEER). High hydrostatic pressure induced PKCα activation (1.42±0.2 vs 0.8±0.05 control, p=0.029; N=5) and the phosphorylation of eNOS at T495 (1.6±0.1 vs 0.62±0.08 control; p=0.0319; N=3), which was used as a correlation to eNOS uncoupling. This was associated with increased RhoA activity (0.009±0.001 vs. 0.005±0.001 control; p=0.0247; N=5), RhoA nitration (2.1±0.4 vs 1.0±0.02 control, p=0.0511; N=4) and VE-cadherin internalization. HLMEC exposed to control and high pressure conditions were transferred to gold electrodes (ECIS assay) to monitor TEER as indices of barrier recovery. High pressure caused a delay in barrier recovery and a decrease in the maximum TEER after 24 hours (0.952±0.16 vs 1.55±.019 control; p=0.0412; N=4). Fasudil, a Rho inhibitor, mitigated the effects of pressure on barrier recovery (1.996±0.79 vs 0.968±0.44 pressure; p<0.0001; N=4). Altogether, these findings suggest that pressure induces endothelial barrier disruption via PKCα-mediated eNOS uncoupling and subsequent activation of RhoA. This may be important in conditions in which pulmonary pressure can increase abruptly, including heart failure.
Abstract 13559: Activation of PDGFRA Signaling Contributes to Filamin C-Related Arrhythmogenic Cardiomyopathy
Authors: Chen Suet , Lam Chi Keung , wan ying-wooi , Gao Shanshan , MALAK Olfat , Lombardi Raffaella , Ambardekar Amrut V , Bristow Michael R , Gigli Marta , sinagra Gianfranco , Graw Sharon L , Taylor Matthew , Wu Joseph C , Mestroni Luisa
Published: April 2022

FLNC
truncating mutations (
FLNCtv
) are prevalent causes of inherited dilated cardiomyopathy (DCM). Notably, carriers of truncating mutations in
FLNC
are at high risk of developing arrhythmogenic cardiomyopathy (ACM). We investigated the molecular mechanisms of mutant FLNC in the pathogenesis of arrhythmogenic DCM (a-DCM) using patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). Our
in vitro
electrophysiological and cell-contraction studies at the single cell level demonstrated that iPSC-CMs from patients with 2 different truncating mutations in
FLNC
displayed reduced contractility and an arrhythmia phenotype associated with dislocation of connexin 43 (GJA1) from the cell membrane as shown by immunofluorescence. iPSC-CMs with FLNC ablation revealed a similar phenotype, suggesting loss of function as a mechanism for arrhythmogenesis in FLNC truncating mutations. Furthermore, our mechanistic studies showed that cell-cell adhesion/β-catenin/PDGFRA signaling pathways were activated in the FLNC-mutant iPSC-CMs compared to the isogenic wildtype iPSC-CMs. Co-immunoprecipitation and proteomic analysis identified β-catenin (CTNNB1) as a novel binding partner of FLNC. FLNC deficiency induced nuclear translocation of CTNNB1 and subsequently activated the platelet-derived growth factor receptor-alpha (PDGFRA) pathway. These findings were corroborated by RNA sequencing and immunoblots on human hearts with a-DCM and
FLNCtv
mutations. We also demonstrated that PDGFRA inhibition rescued GJA1 membrane localization, prevented nuclear localization of CTNNB1 and improved contraction and electrical function of FLNC-mutant iPSC-CMs. Taken together, our findings suggest that PDGFRA signaling is implicated in the pathogenesis of a-DCM caused by FLNC haploinsufficiency mutations and that inhibition of this pathway is a potential therapeutic strategy for preventing arrhythmias in FLNC related cardiomyopathies.
Abstract 13561: Does the Use of Advanced Therapies Improve Outcomes During Pregnancy and Post Partum Period in Patients With Group I Pulmonary Hypertension
Authors: Polisetty Sanjay , Zepeda Ignacio , Quispe Jesus R , Taub Cynthia C
Published: April 2022

Introduction:
Poor outcomes have been reported in Pregnant patients with WHO Group I Pulmonary Hypertension (PH) before the advent of PH targeted therapies. We performed a systematic review and meta-analysis with the goal of evaluating the association between mortality rates and PH targeted therapies in pregnant women with WHO group 1 PH.

Methods:
PubMed Database was searched with keywords “pulmonary hypertension”, “pregnancy” from inception to December 2020. Inclusion criteria: >10 pregnancies, maternal mortality reported and WHO Classification available. A meta-analysis was performed to evaluate the association between maternal death and treatment with PH targeted therapies in patients with WHO group 1 PH. All other WHO groups were excluded.

Results:
Seven studies, published between 1992 and 2016, including 91 patients with WHO group 1 PH met inclusion criteria and were analyzed. (Table 1) Most common etiologies were Idiopathic PH and Congenital Heart Disease. Mortality ranged from 8.3% to 36.3%. Use of PH targeted therapies ranged from 25% to 100%. There was a trend towards survival benefit with PH targeted therapies compared with no therapy. This trend was not statistically significant. Of all deaths reported (n=18), thirteen (72.2%) occurred postpartum.

Conclusions:
Mortality in pregnant patients with WHO group I PH remains high; most deaths were due to PH crisis and occurred postpartum. Increased monitoring in the postpartum period is likely warranted. Studies were retrospective with small sample sizes. Larger and higher quality studies are needed to determine if PH targeted therapies improve mortality in pregnant patients with WHO group I PH.
Abstract 13566: Blood Volume Analysis Phenotypes in Heart Failure Patients Supported With Left Ventricular Assist Device
Authors: Yaranov Dmitry , Silver Marc , Thompson Soren , Strobeck John , Jefferies John L
Published: April 2022

Introduction:
Left ventricular assist device (LVAD) offers advanced heart failure (HF) patients increased survival, life quality and functional status however little information is available regarding the underlying deranged circulatory physiology of LVAD patients. In patients with HF, wide variations in intravascular volumes (total blood volume (TBV), plasma volume (PV) and red blood cell volume (RBCV)) have been measured with blood volume analysis (BVA) and distinct phenotypes have emerged.

Methods:
BVA used in a single center to evaluate 22 LVAD patients (17M/5W), aged 32-70yrs, BMI 37.5(avg), LVADs implanted 42-1912 days before BVA. All patients had successful completion of BVA.

Results:
Only 4/23(17%) had normal TBV and RBCV. Graph1. Eleven patients (50%) were anemic, 3 (14%) with hypovolemia. Overall, 6 patients (27%) were hypervolemic with variances reaching +80%, including 2 patients (9%) with significant hypervolemia and polycythemia indicating heightened risk of thrombosis. Three patients (14%) presented with hypovolemia indicating increased risk for organ failure. Figure 1. shows these variances in more recently implanted LVAD patients as more extreme compared to more remotely.

Conclusions:
As in patients with advanced HF, wide TBV derangements are seen in LVAD patients up to 64 months post LVAD placement. Anemia persists in 50% and polycythemia is present in 9%, both of which are prognostic in HF patients. An early signal is some lesser variances over long time periods, indicating that long-term survival may be associated with lesser volume derangements. These variances, not suspected clinically, inform clinicians of additional therapeutic approaches that may improve host and device outcomes including recovery, safety, and device durability. Patient and clinician acceptance and adoption of BVA was excellent and BVA phenotypes add significant value to centers implanting LVADs.