bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 14713: Renal Denervation: Impact on Non-ST Segment Elevation Myocardial Infarction Rates in Patients With Hypertensive Heart Disease
Authors: Sibeko Siyolise S , Heradien Marshall J , Van Der Bijl Pieter , Janse van Rensburg Rene , Stilwaney Warren , Peterson Dale , Saaiman Andre A , Greyling Christeman J , Brink Paul A
Published: May 2021

Introduction:
Catheter-based renal denervation (RDN) is an emerging therapy for hypertension, with potential ancillary benefits, e.g. a decrease in atrial fibrillation. Little is known about its effects on coronary artery disease (CAD) and acute coronary syndromes (ACS), e.g. non-ST segment elevation myocardial infarction (NSTEMI).

Hypothesis:
RDN reduces the incidence of NSTEMI in patients with hypertension and CAD.

Methods:
Data were retrospectively analyzed from the Renal Sympathetic Denervation Prevents Atrial Fibrillation in Patients with Hypertensive Heart Disease (RDPAF) trial (NCT01990911), which prospectively randomized individuals with uncontrolled hypertension and hypertensive heart disease to RDN or sham procedure groups in a 1:1 fashion. All patients required an indication for invasive coronary angiography. The impact of RDN on incident NSTEMI was evaluated with a log-rank test.

Results:
A total of 80 patients (mean age 65±8 years, 73% male) were analyzed: 42 (53%) patients underwent RDN, while 38 (47%) received sham-RDN. Baseline characteristics did not differ between groups: 54% of the total study population had diabetes mellitus, 88% took statins, 13% were current smokers and 68% had established CAD. After a mean follow-up of 38±23 months, 9 (11%) patients experienced a NSTEMI: 1 RDN (2.38%) vs 8 sham patients (21%) (OR: 0.092; 95% CI: 0.01 to 0.77; p=0.009; figure). Office systolic blood pressures decrease after six months’ follow-up did not differ between groups (-12.88mmHg in RDN vs. -9.13 mmHg in sham group; p= 0.49).

Conclusions:
Hypertensive patients who underwent RDN experienced a lower rate of NSTEMI during long term follow-up, compared to a sham-RDN control group. This may signal a novel benefit of RDN, i.e. a reduction in the incidence of ACS. Larger, prospective studies are needed to test this hypothesis and unravel potential protective mechanisms of RDN.
Abstract 14746: A National Level Analysis of Long-term Outcomes in Patients With Carotid Body Tumors
Authors: Aranda-Michel Edgar , Sultan Ibrahim , Brown James , Bianco Valentino , Habertheuer Andreas , Okusanya Olugbenga T
Published: May 2021

Introduction:
Carotid body tumors represent the most common site for extra-adrenal paragangliomas. Surgical resection is the treatment of choice as a low percentage of these tumors are malignant. Here we present long-term outcomes of a contemporary cohort of patients with a carotid body tumor.

Methods:
The national cancer database was quired for all cases of a carotid body tumor between 2004-2015. All baseline variables were gathered from the database. Kaplan-Meier curves were generated for the entire cohort to assess overall survival. The group was split into surgical and non-surgical cohorts. Survival was assessed via Kaplan-Meier estimates. Patients that underwent surgery were divided based on isolated surgical therapy or multimodal therapy (surgery with radiation or chemotherapy). Cox multivariable analysis was used to determine independent predictors for mortality.

Results:
The search returned 130 patients with a carotid body tumor. The average age of this cohort was 47 years and the majority were women (58.5%). A small proportion (9.2%) of the cohort had a metastasis at the time of diagnosis. Most patients underwent surgery (80%) followed by radiation (44.6%). The overall survival of the cohort was 81.5% at 10 years
(Figure 1A)
. Long-Term survival was higher in the surgical cohort (P=0.001)
(Figure 1B)
. Patients with multimodal therapy survived longer than those that underwent surgery alone (P=0.007)
(Figure 1C).
On Cox multivariable analysis
(Figure 1D)
, only radiation was a predictor for survival (HR 0.25, P=0.008). Having a metastasis on the time of diagnosis was a predictor for worse outcomes (HR 4.45, P=0.03).

Conclusions:
While surgery had a survival benefit on Kaplan-Meier analysis, when risk adjusting for other variables, radiation was the only treatment that conferred a survival benefit; an interesting finding given the historical standard of surgical management. Despite improvements in therapeutic modalities, metastasis on diagnosis carries an increased mortality, favoring aggressive treatment.
Abstract 14771: Obstructive Sleep Apnea is Associated With Cardiac Dysfunction in Children With Congenital Heart Disease
Authors: Combs Daniel , Fernandez Vanessa , barber brent j , Morgan Wayne J , Hsu Chiu-Hsieh , Andrews Jennifer , Parthasarathy MD Sairam , Klewer Scott E , Seckeler Michael D
Published: May 2021

Introduction:
Obstructive sleep apnea (OSA) is associated with cardiac dysfunction in children without congenital heart disease (CHD). Children with CHD are at increased risk for OSA and may be susceptible to further cardiovascular consequences due to OSA but the extent and nature of such cardiovascular effects of OSA are unknown.

Methods:
Children (6-17 years old) with corrected CHD without current cyanosis or Down syndrome were recruited from pediatric cardiology clinic. Home sleep tests were done to determine the presence and severity of OSA. OSA was defined as an obstructive apnea hypopnea index (oAHI) ≥1. Mild OSA was defined as an oAHI of ≥1 to <5 and moderate OSA was defined as an oAHI of ≥5 to <10. Standard clinically indicated echocardiograms were performed in clinic. Echocardiographic findings were compared between children with CHD with and without comorbid OSA using t-tests, Wilcoxon-sign rank tests as well as linear or logistic regression as appropriate.

Results:
Thirty-two children had sleep study and echocardiographic data available. OSA was present in 18 children (56%). OSA was mild in 89% and moderate in 11% of cases. There were no significant differences in age, body mass index, CHD severity, gender or ethnicity between children with and without OSA. Children with OSA had larger height-indexed right ventricular end-diastolic diameter (RVDi) compared to those without OSA (median 1.35, 95% CI 1.09, 1.56 vs. 1.21, 95% CI 1.01, 1.57; p=0.04). Children with moderate OSA had a reduced left ventricular shortening fraction compared to both those with mild OSA and no OSA (30.0 ± 6.1% vs. 38.7 ± 4.4%; p=0.009 and 39.2 ± 3.6%; p=0.007, respectively). Children with moderate OSA had increased left ventricular end-systolic diameter compared to those with mild OSA and no OSA (3.4 ± 0.4 cm vs. 2.5 ± 0.4; p=0.007 and 2.4 ± 0.5; p=0.001, respectively). Children with an RVDi above the median were seven times more likely to have OSA than those with an RVDi below the median (odds ratio 6.9.; 95% CI 1.3, 35; p=0.02).

Conclusions:
OSA is associated with changes in cardiac morphology and reduced contractility in children with CHD. Additionally, the presence of right ventricular dilation may suggest the need for OSA evaluation in children with CHD.
Abstract 14811: Disparities in Prevalence of Hypertension and Hypertensive Urgency by Race and Hispanic Origin in the Wisewoman Population, 2014 to 2018
Authors: Nwaise Isaac , Vaid Isam , Blum Ethan
Published: May 2021

Background:
Hypertension is a preventable risk factor for heart disease and stroke. Patients with hypertensive urgency should seek immediate medical assistance to prevent organ damage, injury, disability, or death.

Objective:
This study examined disparities in the prevalence of hypertension (blood pressure (BP) ≥130/80 mm Hg) and hypertensive urgency (BP ≥180/110 mm Hg) in the WISEWOMAN population. WISEWOMAN represents the Well-Integrated Screening and Evaluation for Women Across the Nation programs that serve a diverse uninsured and underinsured population in the United States.

Methods:
WISEWOMAN data (January 2014- December 2018) were obtained from 19 state health departments and two Alaska tribal organizations. Women aged 40-64 years with hypertension or hypertensive urgency were identified based on BP readings at a screening visit. The data were stratified, and prevalence was calculated by race and Hispanic origin.

Results:
In the WISEWOMAN population there were 25,098 women with hypertension. Overall prevalence of hypertension was 38.5 percent and the prevalence of hypertensive urgency was 4.6 percent. Non-Hispanic black (NHB) women had the highest prevalence of hypertension (67.1 percent) followed by non-Hispanic White (NHW) women (40.2 percent) and Hispanic women (26.5 percent). NHB women (6.1 percent) had the highest prevalence of hypertensive urgency followed by NHW women (4.5 percent) and Hispanic women (3.4 percent).

Conclusion:
Differences in prevalence of women with hypertension and hypertension urgency were statistically significant among race and Hispanic origin. Furthermore, NHB women had disproportionally higher prevalence of hypertension and hypertensive urgency than NHW women and Hispanic women.Keywords: Hypertension, Hypertensive urgency, WISEWOMAN

Table 1: Mean Age, Number and Percentages of Women Screened, Women with Hypertension and those with Hypertensive Urgency among WISEWOMAN Participants, 40-64 years old, January 2014- June 2018. By Race and Hispanic origin
Abstract 14823: Comparison of a Novel Computed Tomography-Based Assessment of Mitral Annular Calcification to Transthoracic Echocardiogram
Authors: Park Jakob , Higgins Angela Y , Kim Yekaterina , Kay Bradley , Faridi Kamil , McNamara Robert L , Agarwal Vratika , MOJIBIAN HAMID , Sugeng Lissa , Hur David
Published: May 2021

Introduction:
Mitral annular calcification (MAC) is associated with increased stroke and death. The typical assessment by transthoracic echocardiography (TTE) is qualitative visual rating (VR), but this technique is user-dependent and lacks a gold standard for grading. Computed tomography (CT) has high sensitivity for calcium and can quantify MAC. The purpose of this study is to standardize grading of MAC and compare TTE-based assessment of MAC with CT.

Methods:
The analysis included 60 patients with non-contrast CT and TTE prior to aortic valve replacement or mitral valve (MV) repair. MAC was assessed on TTE by VR (none, mild, moderate, severe), a previously described echo calcium score (ECS), and systematic MAC grading (SMAC). TTE-based MV parameters were recorded. CT data were measured for calcium volume (MACV) via proprietary software (Visage Imaging) by an independent rater with 3D regions of interest in the MV area.

Results:
Mean age was 77 ± 11; 42% of patients were female. MACV for tertile-based groups (lowest, middle, highest) are shown in the Table. CT detected MAC in a notable portion of patients without MAC by TTE-derived methods: in 16 of 29 patients (55%) by VR, in 5 out of 15 (33%) by ECS, and in 5 out of 16 (31%) by SMAC. Fifteen of 22 patients (68%) with mild MAC by VR had middle or high-tertile MAC on CT. MACV-derived categories reclassified 65%, 60%, and 54% of patients compared with VR, ECS, and SMAC grading by TTE, respectively. Differences were also found across MACV categories for MV velocity, transmitral gradient, and E/e’. Except E/e’, trends were independent of TTE-based MAC analysis and significant after adjusting for mitral regurgitation or stenosis.

Conclusions:
TTE has limited ability to detect mild MAC compared with CT. This novel CT-based volumetric MAC assessment is feasible and can improve standardized quantification and sensitivity to detect MAC at lower values. Higher MACV by CT was associated with increasingly abnormal MV flow and diastology.
Abstract 14833: The Association Between Cardiovascular Disease Knowledge and Risk Factors Among African American Breast Cancer Survivors in the Deep South
Authors: Williams Michelle S , Anyimukwu Chizoba
Published: May 2021

Introduction:
African American breast cancer survivors in the Deep South have a disproportionately high burden of cardiovascular disease (CVD) mortality. This is due, in large part, to multiple potentially modifiable CVD risk factors that are disproportionately high in this group, such as high blood pressure, obesity, and poor dietary habits. The purpose of this study was to assess the association between CVD risk factors and heart disease knowledge among African American breast cancer survivors in the Deep South.

Hypothesis:
We hypothesize that the key CVD risk factors (smoking, BMI, physical activity, healthy diet, total cholesterol, blood pressure, and blood sugar) will be positively associated with heart disease knowledge score.

Methods:
The Heart Disease Knowledge Questionnaire was used to assess the participants’ knowledge of heart disease and heart disease risk factors. Questions from My Life Check were used to assess the participants CVD risk factors. Multivariate regression analyses were performed to determine which CVD risk factors and demographic characteristics can predict the participants’ heart disease knowledge score.

Results:
Seventy African American breast cancer survivors living in the Deep South enrolled in the study. A research team member administered the questionnaires over the phone. The mean age of the participants was 56.76 years (± 10.36) and 42.9% had a college degree or higher level of education. Results of a multivariate regression analysis showed that the number of healthy diet score components was the only cardiovascular health metric that was statistically significantly associated with heart disease knowledge score (p = .01). Education level was the only demographic characteristic that was statistically significantly associated with heart disease knowledge score (p = .004).

Conclusions:
Our results indicate that women with more knowledge of heart disease and higher levels of education are more likely to have better cardiovascular health metrics. Our findings underscore the need to disseminate and implement health education interventions aimed at increasing knowledge of modifiable CVD risk factors that are targeted towards African American breast cancer survivors in the Deep South.
Abstract 14838: Diagnostic Referral Biases Affect Black and Female Patients With Severe Aortic Stenosis
Authors: Skendelas John P , DeRose Joseph J , Goldstein Daniel J , Forest Stephen J
Published: May 2021

Introduction:
The role of racial and socioeconomic factors, using the novel distressed communities index (DCI), on referral patterns in patients with severe aortic stenosis (AS) is poorly characterized.

Hypothesis:
Non-White patients are less likely to be referred for possible aortic valve intervention (AVI).

Methods:
Between January 1, 2010 and December 31, 2019 all adult patients with evidence of severe AS on echocardiogram were identified. Patients with prior aortic valve replacement were excluded. Referral and non-referral were determined in the electronic medical record (EMR) up to 14 days after index echocardiogram. In absence of referral, patients who died within 14 days were excluded. All patients were included in a multivariate logistic regression model of non-referral to adjust for statistically significant differences in age, sex, pre-existing medical comorbidities, DCI score, and AS hemodynamics.

Results:
Of the 179,483 patients identified, 1535 met inclusion criteria for the study. The overall mean age was 80.2 years (95% CI [79.6-80.8]) and was composed of White/Caucasian (50.7%), Black/African American (17.9%), Hispanic/Latino (26.1%), Asian (2.8%), and majority female (58.5%) patients. Female (OR 1.442, 95% CI [1.113-1.866] and Black (OR 1.468, 95% CI [1.023-2.106]) patients faced referral disparities, in spite of adjustment for advanced age (OR 3.739, 95% CI [2.556-5.470]) and dementia (OR 3.114, 95% CI [2.053-4.722]). Pre-existing stroke was collinear with dementia and excluded. In contrast, patients with history of coronary artery disease and those who were evaluated after initiation of the electronic medical record were more likely to be referred.

Conclusions:
When adjusted for medical comorbidities and socioeconomic factors, Black and female patients were less likely to be referred for possible AVI. Additional studies are required to characterize disparities at other levels of healthcare utilization.
Abstract 14839: High-resolution Spatiotemporal Changes in Dominant Frequency and Structural Organization During Persistent Atrial Fibrillation
Authors: Pong Terrence , Aparicio Valenzuela Joy , Cyr Kevin J , Carlton Cody , Sakhamuri Sasank , LEE Anson M
Published: May 2021

Introduction:
Spatiotemporal differences in atrial activity are thought to contribute to the maintenance of atrial fibrillation (AF). While recent evidence has identified changes in dominant frequency (DF) during the transition from paroxysmal to persistent AF, little is known about the frequency characteristics of the epicardium during this transition. The purpose of this study was to perform high-resolution mapping of the atrial epicardium and to characterize changes in frequency activity and structural organization during the transition from paroxysmal to persistent AF.

Hypothesis:
In a porcine model of persistent AF, we tested the hypothesis that the epicardium undergoes spatiotemporal changes in atrial activity and structural organization during persistent AF.

Methods:
Paroxysmal and persistent AF was induced in adult Yorkshire swine by atrial tachypacing. Atrial morphology was segmented from magnetic resonance imaging and high-resolution patient-specific flexible mapping arrays were 3D printed to match the epicardial contours of the atria. Epicardial activation and DF mapping was performed in four paroxysmal and four persistent AF animals using personalized mapping arrays. Histological analysis was performed to determine structural differences between paroxysmal and persistent AF.

Results:
The left atrial epicardium was associated with a significant increase in DF between paroxysmal and persistent AF (6.5 ± 0.2 vs. 7.4 ± 0.5 Hz, P = 0.03). High-resolution spatiotemporal mapping identified organized clusters of DF during paroxysmal AF which were lost during persistent AF. The development of persistent AF led to structural remodeling with increased atrial epicardial fibrosis. The organization index (OI) significantly decreased during persistent AF in both the left atria (0.3 ± 0.03 vs. 0.2 ± 0.03, P = 0.01) and right atria (0.33 ± 0.04 vs. 0.23 ± 0.02, P = 0.02).

Conclusions:
In the porcine model of persistent AF, the epicardium undergoes structural remodeling with increased epicardial fibrosis, reflected by changes in atrial organization index and dominant frequency.
Abstract 14845: Remnant Cholesterol and Incident Atherosclerotic Cardiovascular Disease: A Pooled Cohort Primary Prevention Study
Authors: Quispe Renato , Martin Seth S , Michos Erin D , Lamba Isha , Blumenthal Roger S , Saeed Anum , Ac Lima Joao , Puri Rishi , Nomura Sarah , Tsai Michael Y , Wilkins John T , Ballantyne Christie M , Nicholls Stephen J , Jones Steven R , Elshazly Mohamed B
Published: May 2021

Introduction:
Emerging evidence suggests that remnant cholesterol (RC) promotes future atherosclerotic cardiovascular disease (ASCVD) events. Our aim was to estimate the risk associated with RC beyond low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (apoB).

Hypothesis:
RC provides incremental prognostic information regarding incident ASCVD, independent of LDL-C and apoB.

Methods:
We pooled data from 17,532 individuals from Atherosclerosis Risk in Communities study (n=9,748), Multi-Ethnic Study of Atherosclerosis (n=3,049) and Coronary Artery Risk Development in Young Adults (n=4,735), who were ASCVD-free at baseline and had measurements of lipids, apoB and apolipoprotein A1. RC was calculated as non-high-density cholesterol (non-HDL-C) minus LDL-C estimated by the Martin/Hopkins equation. Adjusted Cox models were used to estimate the risk for incident ASCVD associated with log RC levels. We also performed discordance analyses examining relative ASCVD risk in discordant/concordant groups of RC and LDL-C across median cutpoints and cutpoints of percentile equivalence to LDL-C targets (70 and 100 mg/dL).

Results:
Mean age of participants was 52.3±17.9 years, 56.7% women and 34% black. There were 2,143 ASCVD events over median follow-up of 18.7 years. After multivariable adjustment including apoB and HDL-C, logRC was associated with higher ASCVD risk [HR 1.42, 95% CI (1.23-1.63)]. In discordance analyses, the high RC and low LDL-C group (≥/<median) was associated with increased ASCVD risk compared to the low/low concordant group [1.17, (1.01-1.35)] but the low RC and high LDL-C group was not. Similar results were shown when examining discordance across lower cutpoints.

Conclusion:
In ASCVD-free individuals, elevated RC levels were associated with ASCVD independent of traditional risk factors and LDL-C and apoB levels. RC assessment and management in primary prevention, beyond LDL-C and apoB, is useful and requires further scrutiny.
Abstract 14846: Artificial Intelligence and Clinical Stability After the Norwood Operation
Authors: Aljiffry Alaa , Xu Yanbo , Hong Shenda , Long Justin , Sun Jimeng , Maher Kevin
Published: May 2021

Background:
Postoperative management of the neonate following the Norwood operation is among the most complex and challenging in pediatric critical care. Artificial intelligence is poised to assist in management of this complex population.

Methods:
We developed a convolutional neural network (CNN) model trained on electrocardiogram (ECG) waveforms collected from 45 neonates after the Norwood procedure. Waveforms from the first two postoperative days (critical) and the day prior to transfer out of the ICU (stable) were used for training. The model was validated on 10 post-Norwood neonates. Models were compared to traditional machine learning algorithms on non-waveform data, heart rate variability, and then combined in a final model to optimize performance. Retrospective clinical observation scoring was completed for comparison.

Results:
The CNN model on 3-lead ECG yielded an area under the curve of the receiver operating characteristic (AUC-ROC) of 0.97 ( 0.02). The final model combining predictions from the CNN, random forest on vital signs, and logistic regression on pH, lactic acid, and base deficit values achieved 0.98 ( 0.02). Retrospective clinical observations agreed with the final model 78% of the time.

Conclusions:
Application of this novel combined machine learning model can accurately detect changes in clinical status as patients progress from critically ill to stable following the Norwood procedure, yielding impressive clinical insights from the ECG beyond what is currently possible. This work provides the basis for the development of a novel bedside monitoring tool and suggests new ways artificial intelligence may influence clinical care beyond predicting deterioration events.
Abstract 14849: Lifetime Benefit of Empagliflozin in Extending Survival Free From Insulin Initiation in Type 2 Diabetes and Cardiovascular Disease: An Actuarial Analysis of EMPA-REG OUTCOME
Authors: Vaduganathan Muthiah , Sattar Naveed , Fitchett David H , Ofstad Anne Pernille , Brueckmann Martina , George Jyothis T , Verma Subodh , Mattheus Michaela , Wanner Christoph , Inzucchi Silvio E , Zinman Bernard , Butler Javed
Published: May 2021

Background:
Many patients with type 2 diabetes (T2D) will, over time, require insulin therapy for glycemic control. Treatment-attendant adverse effects of insulin such as weight gain and hypoglycemia may be especially problematic in those with CVD. Delaying the need for insulin initiation may therefore be an important therapeutic goal, especially in those with CVD.

Methods:
This actuarial analysis evaluated the 3,633 (52%) of 7,020 EMPA-REG OUTCOME participants who were not using insulin at baseline. Patients were randomized to the SGLT2 inhibitor empagliflozin (EMPA) 10mg, 25mg, or placebo (PBO). After the first 12 weeks, changes in background antihyperglycemic therapy were allowed. We estimated survival time free from insulin initiation (sustained over ≥2 consecutive study visits) over patients’ lifetimes by using baseline age as the time horizon. Age-based Kaplan-Meier survival curves were constructed for each year of age between 45 and 80 years. Differences in area under the survival curve between treatment arms represented treatment effects on time spent alive and free from insulin initiation.

Results:
During median follow-up of 3.2 years, insulin was required in 172 patients (7.1%) with EMPA and 196 (16.4%) with PBO. Lifetime benefits on insulin-free survival were inversely related to baseline age, ranging from 1.4 to 11.3 years. For a 45-year-old, estimated insulin-free survival was 20.1 years with EMPA and 10.0 years with PBO (difference: 10.1 years; 95% CI 5.7-14.5 years; P<0.0001). At age 60 years, insulin-free survival was 16.7 vs. 10.5 years (difference: 6.2 [4.6-7.8]; P<0.0001), and at age 75 years, 9.7 vs. 8.1 years (difference: 1.5 [0.0-3.1]; P=0.056).

Conclusions:
Assuming stable lifetime effects, we estimate that initiation of EMPA prolongs time alive free from need for insulin by 1.4 to over 11 years among adults with T2D and CVD. While benefits were most pronounced among younger patients, EMPA reduced the need for insulin across a broad age range.
Abstract 14853: Acute Inhibition of Mitochondrial Reactive Oxidative Species Improves Endothelial SK Channel Function Following Cardioplegic Hypoxia/Reperfusion and Diabetes
Authors: Song Yi , Zhang Zhiqi , Xing Hang , He Yixin , shi guangbin , Wu Su , Harrington Elizabeth O , Sellke Frank W , Feng Jun
Published: May 2021

Introduction:
Cardioplegic-ischemia/reperfusion (CP-I/R) and diabetes mellitus (DM) are correlated with coronary endothelial dysfunction and inactivated small conductance calcium-activated-potassium (SK) channels. Increased reactive oxidative species (ROS), such as mitochondrial ROS (mROS) may contribute to oxidative injury. Thus, we hypothesized that inhibition of mROS may protect coronary SK channels and endothelial function against CP-I/R-induced injury.

Objective:
A cardioplegic hypoxia and reoxygenation (CP-H/R) model consisting of coronary endothelial cells and small coronary arteries with or without DM were employed for examining whether MT could protect against coronary endothelial and SK channel dysfunction.

Methods:
Small coronary arteries (<150μm) and endothelial cells (MHECs) were dissected from the mouse heart with non-diabetes (ND) and DM (n=6/group). The microvessels or MHECs were subjected to hypoxia with cardioplegia and re-oxygenated. The microvessels or MHECs were treated with or without MT (10
-5
M) 5-minutes before and during CP-hypoxia. Microvascular vasodilation function was assessed in vitro by administration of vasoconstrictor, then ADP or NS309,respectively. K
+
currents of MHECs were measured by whole-cell patch clamp. The levels of endothelial mROS was measured by MitoSox
TM
.

Results:
CP-H/R significantly attenuated endothelial SK channels activity and the coronary relaxation responses to ADP and NS309 in the ND and DM groups. Treatment with MT enhanced coronary relaxation responses to ADP or NS309 (
p
<0.05, Fig 1. A, B), and similar findings were seen in endothelial SK channel currents in both ND and DM MHECs (
p
<0.05, Fig 1. C-F). In addition, treating MHECs with MT reduced CP-H/R-induced mROS in ND and DM groups.

Conclusions:
Administration of MT improves endothelial SK channels activity which may contribute to its enhancement of endothelium-dependent vasorelaxation following CP-H/R.
Abstract 14856: Leadless Pacemaker Implantation in Patients With Paroxysmal Complete Atrioventricular Block
Authors: mendoza ivan , Penalver Jorge , Aranguibel Ninoska N , Jose Chamorro , zambrano Juan P , Mendoza Ivan
Published: May 2021

Introduction:
Transcatheter pacing systems have recently emerged as a safe and effective alternative in treating patients who require right ventricular pacing therapy. Traditionally, patients with atrial fibrillation with slow ventricular response had been benefit from this therapy. More recent, patients with symptomatic paroxysmal complete AV block had been receiving these devices. At this moment there is no data available about the feasibility , safety or outcomes of leadless pacemaker in this subgroup of patients

Objective:
The aim of this study was to assess the feasibility safety and 1 year follow up of the transcatheter leadless pacemaker device in patients with paroxysmal complete AV block .

Methods:
One hundred and ten (110 ) consecutive patients who underwent implantation of a Micra transcatheter leadless pacemaker (LPM)and have been follow up for at least a year were evaluated . Forty one (41) of these patients had the device implanted after experiencing symptomatic paroxysmal complete AV block. A t-test analysis was used to compare patient demographics, total procedure times, complication rates and recaptures necessary during the procedure.

Results:
All the patients with symptomatic paroxysmal complete AV block were implanted successfully with the leadless pacemaker system ( LPN ) . None of the patients suffered complications during the procedures. Fifty three percent ( 53%) were female , mean age of 77 , mean procedure time was 21.1 min. The mean number of recaptures required were 0.48 . None of the patient experienced pacemaker syndrome or progress to complete AV block after 1 year of follow up

Conclusion:
Leadless pacemaker implantation appears to be a safe and feasible alternative for subjects with symptomatic paroxysmal complete AV block . Further studies are required in these subgroup of patients
Abstract 14876: Predictors of Permanent Pacemaker Insertion After TAVR: A Systematic Review and Meta-Analysis
Authors: Gupta Rahul , Malik Aaqib h , Aronow Wilbert S
Published: May 2021

Introduction:
Transcatheter Aortic Valve Replacement (TAVR) has evolved as the standard of care for patient with severe aortic stenosis. Conduction abnormalities leading to permanent pacemaker (PPM) implantation is one of the most common complication after TAVR. The aim of this analysis is to evaluate the predictors associated with increased risk of PPM implantation after TAVR.

Methods:
A comprehensive literature search was performed in PubMed, Embase, and Cochrane to identify relevant trials. Summary effects were calculated using a DerSimonian and Laird random-effects model as odds ratio with 95% confidence intervals for all the clinical endpoints.

Results:
37 observational studies with 71455 patients were identified. The incidence of PPM implantation after TAVR in our analysis was 22%. The risk of PPM implantation after TAVR was more in men, it increased with increasing age, and in patients with diabetes mellitus, presence of right bundle branch block , baseline atrioventricular conduction block, and left anterior fascicular block. Significant predictors of PPM insertion post TAVR included the presence of high calcium volume in the area below left and non-coronary cusp, use of self-expandable valve over balloon-expandable valve, depth of implant, valve size/annulus size, pre-dilatation balloon valvuloplasty and post-implant balloon dilation. However, the risk did not increase with atrial fibrillation, left bundle branch block, baseline interventricular conduction delay, change in QRS duration after the procedure and with the presence of high calcium in the area below right coronary cusp.

Conclusions:
Our meta-analysis identified 14 factors that were significantly associated with increased risk of PPM insertion after TAVR. Early identification of high-risk populations and targeting modifiable risk factors can help to reduce the rate of PPM insertion after TAVR.
Abstract 15070: Micu1 Regulates Mitochondrial Cristae Structure and Function Independent of the Mitochondrial Calcium Uniporter Channel
Authors: Tomar Dhanendra , Thomas Manfred , Garbincius Joanne , Kolmetzky Devin , Salik Oniel , jadiya pooja , Joseph Suresh K , Carpenter April C , Hajnoczky Gyorgy , Elrod John W
Published: May 2021

Background:
MICU1 is an EF-hand domain containing Ca
2+
-sensor regulating the mitochondrial Ca
2+
uniporter channel and mitochondrial Ca
2+
uptake. MICU1-null mouse and fly models display perinatal lethality with disorganized mitochondrial architecture. Interestingly, these phenotypes are distinct from other mtCU loss-of-function models (
MCU, MICU2, EMRE, MCUR1
) and thus are likely not explained solely by changes in matrix Ca
2+
content. Using size-exclusion proteomics and co-immunofluorescence, we found that MICU1 localizes to mitochondrial complexes lacking MCU. These observations suggest that MICU1 may have additional cellular functions independent of the MCU.

Methods:
Biotin-based proximity labeling and proteomics, protein biochemistry, live-cell Ca
2+
imaging, electron microscopy, confocal and super-resolution imaging were utilized to identify and validate MICU1 novel functions.

Results:
The expression of a MICU1-BioID2 fusion protein in

MCU
+/+

and

MCU
-/-

cells allowed the identification of the total vs. MCU-independent MICU1 interactome. LC-MS analysis of purified biotinylated proteins identified the mitochondrial contact site and cristae organizing system (MICOS) components Mitofilin (MIC60) and Coiled-coil-helix-coiled-coil helix domain containing 2 (CHCHD2) as MCU independent novel MICU1 interactors. We demonstrate that MICU1 is essential for proper organization of the MICOS complex and that MICU1 ablation results in altered cristae organization, mitochondrial ultrastructure, mitochondrial membrane dynamics, membrane potential, and cell death signaling. We hypothesize that MICU1 is a MICOS Ca
2+
- sensor since perturbing MICU1 is sufficient to modulate cytochrome c release independent of Ca
2+
uptake across the inner mitochondrial membrane.

Conclusions:
Here, we provide the first experimental evidence of an intermembrane space Ca
2+
- sensor regulating mitochondrial membrane dynamics, independent of changes in matrix Ca
2+
content. This study provides a novel paradigm to understand Ca
2+
-dependent regulation of mitochondrial structure and function and may help explain the mitochondrial remodeling reported to occur in numerous disease states.
Abstract 15075: Exercise Stress Testing and Stress Cardiac Magnetic Resonance Imaging for Detection of Inducible Ischemia in a Large Cohort of Children With Anomalous Aortic Origin of a Coronary Artery
Authors: Qasim Amna , Doan Tam , Pham Tam Dan , Reaves-O’Neal Dana , Molossi Silvana M
Published: May 2021

Introduction:
The current AATS and AHA/ACC guidelines recommend maximal exercise stress test (mEST) to identify ischemia and direct decision-making in patients (pts) with anomalous aortic origin of a coronary artery (AAOCA). Stress cardiac magnetic resonance imaging (sCMR) has reliably identified myocardial perfusion abnormalities.

Hypothesis:
We hypothesize that EST and sCMR do not agree in the detection of inducible ischemia in AAOCA.

Methods:
AAOCA pts <21 years old were prospectively enrolled and evaluated following a standardized approach from 12/2012-12/2019. mEST was performed in pts ≥6 years old, except those who presented with cardiac arrest or physical limitations. Demographic data, coronary anomaly type, EST (symptoms, ST changes, arrhythmias, metabolic parameters) and sCMR data were collected. A mEST was defined as max HR ≥85%ile with a subgroup defined as respiratory exchange ratio (RER) >1.05. Abnormal mEST included: significant ST changes (≥1 mm horizontal or downsloping ST-depression, ≥2 mm upsloping ST depression, ST elevation), high-grade arrhythmia, abnormal peak VO2 (<85% predicted). Continuous and categorical variables were compared using Wilcoxon-Rank sum and Fisher’s exact/χ2 respectively. McNemar’s test was used to determine the agreement between EST and sCMR.

Results:
Of 147 pts with AAOCA and both EST and sCMR, 140 achieved max HR ≥85%ile on EST. Table 1 compares demographics and EST parameters in pts with inducible ischemia on sCMR (+sCMR) vs without (-sCMR). Significant ST changes were seen in 2/26 (7.7%) pts with +sCMR compared to 8/114 (7%) pts with -sCMR. An abnormal mEST did not agree with sCMR in identifying inducible ischemia (McNemar p < 0.001) in all AAOCA patients who achieved max HR, nor in the sub-group with RER >1.05 (n = 88).

Conclusions:
mEST does not agree with sCMR in identifying inducible ischemia in patients with AAOCA. Our data suggest that mEST should not be used alone for the detection of inducible ischemia.
Abstract 15104: Malignant Neoplasms of the Heart in the United States
Authors: Lima Neiberg A , Cwikla Kamil , Byers-Spencer Kristina , Huffman Cuyler , Diaz Mireya , Melgar Thomas , Helmstetter Nicholas
Published: May 2021

Introduction:
Malignant cardiac neoplasms (MCN) are rare and deadly. Metastatic cardiac tumors are known to be more frequent than primary neoplasms of the heart. Due to the uncommon nature of this disease, there are few data-driven studies examining the incidence in the United States or analyzing rates and types of complications. The purpose of our study was to better describe the types, characteristics and trends of MCN in the United States.

Methods:
This study is a retrospective review of data from the HCUP-NIS Database from 2002-2014. Inclusion criteria consisted of the presence of indication for MCN. Additionally, we queried the database for MCN-associated comorbidities and procedures. SAS studio was utilized for analysis.

Results:
The data consists of 482,872,274 weighted hospital discharges, 5,610 of which had MCN. Fifty three percent were male. Eighty percent had a metastatic cardiac tumor and twenty percent had a primary neoplasm of the heart (Figure 01). Median cost of admission was 35,855 USD, three times higher than the national average. A total of 568 (10.12%) patients died during the admission. Stroke and arterial embolization were reported in 192 (3.42%) and 54 (0.96%) cases, respectively. Weight loss, fever and endocarditis were reported in 70 (1.24%), 162 (2.89%) and 53 (0.94%) patients, respectively. Pulmonary hypertension co-occurred in 225 (4.01%) patients. Atrial tachyarrhythmias, ventricular arrhythmias, syncope and cardiac arrest were reported in 1,119 (19.95%), 185 (3.30%), 39 (0.70%), and 88 (1.57%) cases. Sinus node dysfunction and severe AV nodal block co-occurred in 46 and 50 patients.

Conclusions:
Morbidity and mortality are high in patients with MCN. The majority of MCN are associated with metastatic disease, with especially lung, skin/bone/soft tissue and gastrointestinal being the commonest.
Abstract 15115: Clinical Presentation and Medium-term Outcomes in Anomalous Aortic Origin of the Left Coronary Artery: High-risk Features Beyond Interarterial Course
Authors: Wilkes J Kevin , Doan Tam , Reaves O’Neal Dana , Bonilla-Ramirez Carlos , Sachdeva Shagun , Masand Prakash , Mery Carlos M , Binsalamah Ziyad , Caldarone Christopher , McKenzie E. Dean , Molossi Silvana M
Published: May 2021

Background:
Anomalous aortic origin of the left coronary artery (AAOLCA) confers a rare, but significant, risk of sudden cardiac death (SCD) in children. Surgical intervention is recommended for AAOLCA with an interarterial course, with other subtypes considered benign. We aimed to determine the clinical characteristics and outcomes of AAOLCA in a prospective cohort following a standardized approach.

Methods:
All patients with AAOLCA <20 years old were prospectively enrolled. Anatomic details were obtained with coronary computerized tomography angiography (CTA). Myocardial functional studies were obtained under provocative stress, including exercise stress test, stress nuclear perfusion imaging, or dobutamine stress cardiac magnetic resonance. Patients were stratified as high-risk if: 1) episode of aborted SCD, 2) interarterial and/or intramural course, or 3) evidence of myocardial ischemia on functional studies.

Results:
A total of 47 patients (32 male, 68%) with AAOLCA were enrolled, median age 12 [IQR 6.0;15.0] years. Of these, 20 had exertional symptoms (42.5%) and 5 had aborted SCD (10.5%). Thirty-one patients (79%) were classified high-risk, 28% low-risk, and 3 (6%) work-up is ongoing. Of patients with completed work-up, 16/43 (37%) had inducible ischemia and, of these, 2/16 (13%) presented without symptoms and one with aborted SCD as the first symptom. Two patients in our cohort had AAOLCA arising close to the noncoronary sinus, just above the left and noncoronary commissure, resulting in ostial stenosis: one presented with aborted SCD and another with left ventricular dysfunction. To date, 17 patients have undergone repair, median age 10 years [IQR 6.6;15.7]. Median follow-up was 3.9 [IQR 1.3;6.3] years with no significant symptoms and all but 4 patients are cleared from exercise restrictions.

Conclusion:
AAOLCA may present with diverse anatomic configuration and risk stratification is essential to determine management. AAOLCA from the noncoronary sinus may also present with myocardial ischemia and, thus, be classified as high-risk. A multimodality imaging approach is necessary to adequately risk stratify this population. All patients are alive at last follow-up and the majority free from exercise restriction.
Abstract 15128: Clinical Outcomes in Heart Failure Patients With Concurrent Cocaine Use
Authors: Garry Jonah D , Thakkar Anjali , Ma Yifei , Scherzer Rebecca , Hsue Priscilla
Published: May 2021

Background:
While cocaine use is associated with heart failure (HF) with reduced ejection fraction, the impact of cocaine use on HF outcomes including 30-day hospital readmission and survival has not been well described. Accordingly, this study evaluated the impact of cocaine use on 30-day hospital readmissions (heart failure and all cause) and mortality.

Methods:
We performed a case control study of HF patients with an index HF hospitalization at an academic safety net hospital in San Francisco between 2001-2019. 746 HF patients with history of cocaine use were matched to 746 HF patients without cocaine use, based on age, gender, and date of index hospitalization. We compared clinical characteristics, readmission rates, and mortality between these two groups.

Results:
Average age was 53 years and 79% were male. HF patients with cocaine use were more likely to be African American (69.6% vs. 29.8%, p<0.01), have hypertension, liver disease and concurrent use of methamphetamines and opioids. Rates of coronary artery disease, diabetes, chronic kidney disease, HIV, and chronic obstructive pulmonary disease were similar between the groups. There was no significant difference in prescription of guideline directed medical therapies at discharge. Within 30 days of index HF hospitalization, HF patients with cocaine use were more likely to attend follow up (91.8% vs 86.9%, p<0.01), but were more likely to be readmitted for HF (12.1% vs 7.4%, OR 1.75, p<0.01) or other causes (22.4% vs 14.7%, OR 1.67, p<0.01). Over the study period, cocaine use was associated with greater likelihood of death (27.9% vs 20.1%, p<0.01).

Conclusions:
HF patients with comorbid cocaine use were found to have higher likelihood of readmission or death following index HF hospitalization compared to HF patients without cocaine use. As cocaine use continues to grow it is critical to understand the mechanisms underlying cocaine induced cardiovascular pathophysiology, and to identify factors affecting readmission and mortality in this high risk group.
Abstract 15135: Liver Fibrosis Scores Predict Cardiovascular Outcomes in Patients With Previous Myocardial Infarction
Authors: Cao Yexuan , Zhang Meng , Zhang Huiwen , Jin Jinglu , Liu Hui-Hui , Zhang Yan , Guo Yuan-Lin , Wu Na-Qiong , Zhu Cheng-Gang , Xu Rui-Xia , Dong Qian , Li Jian-jun
Published: May 2021

Introduction:
Liver fibrosis score (LFS) has been used for predicting the cardiovascular outcomes (CVOs) in diverse populations. However, the association of LFS with CVOs in patients with previous myocardial infarction (MI) remains undetermined.

Hypothesis:
The aim of the present study was to examine the prognostic value of LFS in patients with prior MI in a prospective cohort.

Methods:
A total of 3718 patients with previous MI were consecutively enrolled from March 2009 to January 2019. Five LFSs were used including the fibrosis-4 (FIB-4) score, non-alcohol fatty liver disease fibrosis score (NFS), Forns score, HUI score and BARD score in the current study. The CVOs covered major adverse cardiac event (MACE), hard endpoint, cardiovascular mortality and all-cause mortality. Cox proportional hazards model was used to calculate hazard ratios (HR) with 95% confidence intervals (CI).

Results:
During a mean follow-up of 47.4±24.8 months, 431 (11.6%) MACE occurred. Kaplan-Meier analysis demonstrated that higher LFSs resulted in a significantly higher probability of CVOs. Compared to the lowest score group, multivariable-adjusted HRs (95% CI) for the highest group of FIB-4, NFS, Forns score, HUI score and BARD score were 1.76 (1.33-2.34), 2.39 (1.71-3.34), 2.46 (1.62-3.74), 1.60 (1.18-2.17) and 1.28 (1.03-1.58), respectively. These LFSs were also independent predictors of hard endpoint, cardiovascular mortality and all-cause mortality. Similar results were observed across subgroups analysis. The addition of LFSs to a prediction model significantly increased the C-statistic for CVOs.

Conclusions:
The present study firstly demonstrated that LF scores might affect the prognosis in patients with previous MI, suggesting that LF scores may be helpful to further risk stratification and supporting LF scores screening in patients with previous MI.
Abstract 15142: Left Bundle Branch Pacing, Procedure Characteristics, Feasibility and Long-term Safety: Insights From a Large Sample Single Center Study
Authors: Huang Weijian , Su Lan , Wang Songjie , Wu Shengjie , Xu Lei , Zheng Rujie , Jiang Limeng
Published: May 2021

Introduction:
Left bundle branch pacing (LBBP) is a novel pacing method and has been proven to have low and stable pacing thresholds. However, data on large numbers of patients with long-term follow-up is still needed to evaluate its feasibility and safety.

Hypothesis:
To evaluate the feasibility and safety of LBBP in a large sample with long-term follow up.

Methods:
This study prospectively enrolled 632 consecutive patients with left bundle branch block, AV block or sick sinus syndrome with attempted LBBP from April 2017 to July 2019. Pacing parameters, ECG, echocardiographic measurements, complications were assessed at implant, and during follow-up of 1, 6, 12 and 24 months.

Results:
LBBP was successful in 618/632 (97.8%) patients according to the strict criteria for LBB capture. Mean follow-up time was 17.8±6.9 months. LBB capture threshold at implant was 0.65±0.27 mV@0.5ms and 0.71±0.35 mV@0.5ms at 2-year follow-up (n=166). Left ventricular ejection fraction were improved in QRS≥120ms and <120ms groups (60.62±14.22% vs. 63.95±11.29 %, p<0.001; 49.77±17.58 % vs. 58.58±12.79 %, p<0.001; respectively). The number of patients with moderate and sever tricuspid regurgitation decreased at 1-year (120 to 66;28 to 16; respectively). Permanent right bundle branch injury occurred in 55 (8.9%) patients. LBB capture threshold increased greater than 2 V in 6 patients, loss of capture in 2 patients, two lead dislodgements requiring operative revision within 1 month after implantation during 2-years follow-up.

Conclusions:
Feasibility and safety of LBBP were confirmed by this large sample size and long-term follow-up study. It is a reliable physiologic method for standards pacing indications.