bluuebunny/crossref_metadata_2025 huggingface dataset:
Long-Term Efficacy of Myoblast Transplantation on Regional Structure and Function After Myocardial Infarction
Authors: Ghostine Saïd , Carrion Claire , Souza Luiz César Guarita , Richard Pascal , Bruneval Patrick , Vilquin Jean-Thomas , Pouzet Bruno , Schwartz Ketty , Menasché Philippe , Hagège Albert Alain
Published: July 2021

Background

Transplantation (Tx) of skeletal myoblasts (SM) within an infarcted myocardium improves global left ventricular (LV) function, although a direct systolic effect remains controversial.

Methods and Results

Global and regional LV functions were studied in a sheep model (n=16) of infarction before (baseline), and 4 (M4), and 12 (M12) months after in-scar injections of autologous SM or culture medium (CM). LV end-diastolic volume (EDV), ejection fraction (EF), wall motion score (WMS), and systolic myocardial velocity gradient (MVG) across the scar were measured by echocardiography with tissue Doppler imaging. Parameters were similar at baseline between groups. At M4, Tx of SM reduced the postinfarction increase in EDV (72±8 versus 105±13 mL in the CM group,
P
<0.05) and the decrease in EF (48±5 versus 33±3% in the CM group,
P
=0.006) although it improved WMS (5.4±1.2 versus 13±2.2 in the CM group,
P
<0.01) and SMVG (0.60±0.13 versus –0.04±.13 seconds
-1
in the CM group,
P
<0.05). Results were similar at M12. In-scar accumulation of myotubes and SM were detected in all Tx animals up to M12, with co-expression of fast and slow isoforms of the myosin heavy chain (MHC) (30% of the fibers versus 0% in the normal skeletal muscle) and decreased collagen density (30±2% versus 73±3%,
P
<0.0001).

Conclusion

For up to 1 year, Tx of SM limits postinfarction EF deterioration and improves systolic scar function through colonization of fibrosis by skeletal muscle cells with expression of both MHC isoforms, which may confer to the graft the ability to withstand a cardiac-type workload.
Safety of Aprotinin Use and Re-Use in Pediatric Cardiothoracic Surgery
Authors: Jaquiss Robert D. B. , Ghanayem Nancy S. , Zacharisen Michael C. , Mussatto Kathleen A. , Tweddell James S. , Litwin S. Bert
Published: July 2021

Background

Hypersensitivity reactions to aprotinin have been reported in adult cardiac surgical patients undergoing initial and re-exposure to the medication. This study describes the incidence and impact of aprotinin hypersensitivity reactions in children undergoing cardiothoracic surgery.

Methods and Results

In this retrospective review of our entire experience with aprotinin (n=865), 681 first exposures, 150 second exposures, and 34 third or higher exposures were examined. Reactions were classified as mild (generalized cutaneous erythema, Type A) or severe (unexplained cardiopulmonary instability after aprotinin exposure, Type B). Records of patients sustaining a reaction were reviewed to assess the impact of the reaction on outcome and to survey reaction management strategies. Reactions occurred in 7 of 681 first exposures (1.0%), of which 2 were Type A and 5 were Type B. In second exposures, there were reactions in 2 of 150 (1.3%), of which both were Type B. In 34 third or higher exposures, there was only 1 reaction (2.9%), which was Type B. Reactions were no more likely on second, third, or higher exposure than on initial exposure. Skin testing had a negative predictive value of 98.9% and a positive predictive value of 20%. Anti-aprotinin IgE was undetectable in 7 of 8 reactor cases tested. No adverse sequelae were attributed to aprotinin reaction.

Conclusions

The risk of hypersensitivity reactions to aprotinin is low in children undergoing cardiothoracic surgery, even with multiple exposures to the medication. Reactions are more likely with re-exposure, and risk increases with multiple exposures. Neither skin testing nor assays for IgE identified reactors.
Viral Gene Transfer of the Antiapoptotic Factor Bcl-2 Protects Against Chronic Postischemic Heart Failure
Authors: Chatterjee Subhasis , Stewart Allan S. , Bish Lawrence T. , Jayasankar Vasant , Kim Elizabeth M. , Pirolli Timothy , Burdick Jeffrey , Woo Y. Joseph , Gardner Timothy J. , Sweeney H. Lee
Published: July 2021

Background

Apoptosis secondary to acute ischemia and chronic remodeling is implicated as a mediator of heart failure. This study was designed to assess the effect of in vivo viral gene transfer of the anti-apoptotic factor Bcl-2 to block apoptosis and preserve ventricular geometry and function.

Methods and Results

In a rabbit model of regional ischemia followed by reperfusion, an experimental group treated with adeno-Bcl-2 was compared with a control group receiving empty vector adeno-null. Function was assessed by echocardiography, and sonomicrometry of the border zone was compared with the normal left ventricle (LV). Animals were killed at 6 weeks, and an additional group was killed after 3 days to see whether virus administration conferred an immediate effect. Animals that were administered Bcl-2 maintained higher ejection fractions at 2, 4, and 6 weeks compared with controls. Sonomicrocrystals demonstrated greater protection of border zone fractional shortening at 6 weeks. The Bcl-2 group had superior preservation of LV geometry with less ventricular dilatation and wall thinning. There was also reduced apoptosis compared with the controls. Finally, in the animals killed at 3 days, no functional difference was observed between the Bcl-2 and control groups.

Conclusions

Gene transfer of Bcl-2 preserves LV function after ischemia despite the absence of an observed acute protective effect. The benefit at 6 weeks is postulated to result from a Bcl-2–mediated reduction in apoptosis and ventricular remodeling. Adeno–Bcl-2 administration offers a potential strategy to protect the heart from late postischemic heart failure.
Neurodevelopmental Outcome After Congenital Heart Surgery: Results From an Institutional Registry
Authors: Forbess Joseph M. , Visconti Karen J. , Hancock-Friesen Camille , Howe Robert C. , Bellinger David C. , Jonas Richard A.
Published: July 2021

Objective

Increased survival in children with critical congenital heart disease (CHD) has raised interest in the neurodevelopmental sequelae of these lesions. This investigation is part of an institutional effort to examine the neurodevelopment of 5-year-old children following repair or palliation of CHD.

Methods

We performed a battery of neuropsychological tests on a sample of 243 children between 1998 and 2001.

Results

In the sample as a whole, mean full-scale (FSIQ), verbal (VIQ), and performance (PIQ) IQ scores were in the normal range (96.8±15.9, 97.8±14.6, and 96.3±17.1, respectively). Anatomic, demographic, and perioperative factors were assessed for impact on neurodevelopment. In multiple regression analysis, lower socioeconomic status (SES) and the diagnosis of velocardiofacial syndrome (VCFS) predicted a lower FSIQ (
P
=0.01, and
P
=0.001, respectively). A single ventricle diagnosis (
P
=0.06), longer postoperative ICU stay (
P
=0.08), and cumulative duration of hypothermic circulatory arrest (HCA) (
P
=0.09) approached significance as predictors of lower FSIQ.

Conclusion

Children with CHD, on the whole, appear to be performing within the average range in terms of intellectual abilities. Lower SES and VCFS are associated with lower IQ scores. Trends toward worse outcomes were observed in single ventricle patients, biventricular patients with longer postrepair ICU stays, and patients subjected to longer periods of HCA.
Atorvastatin Inhibits Hypercholesterolemia-Induced Calcification in the Aortic Valves via the Lrp5 Receptor Pathway
Authors: Rajamannan Nalini M. , Subramaniam Malayannan , Caira Frank , Stock Stuart R. , Spelsberg Thomas C.
Published: July 2021

Background—

Calcific aortic valve disease is the most common indication for surgical valve replacement in the United States. The cellular mechanisms of valve calcification are not well understood. We have previously shown that cellular proliferation and osteoblastogenesis are important in the development of valvular heart disease. Lrp5, a known low-density receptor-related protein, plays an essential role in cellular proliferation and osteoblastogenesis via the β-catenin signaling pathway. We hypothesize that Lrp5 also plays a role in aortic valve (AV) calcification in experimental hypercholesterolemia.

Methods and Results—

We examined the effects of cholesterol and atorvastatin in Watanabe rabbits (n=54). Group I (n=18) received a normal diet, group II (n=18) a 0.25% cholesterol diet, and group III (n=18) a 0.25% (w/w) cholesterol diet with atorvastatin for the development of calcification. The AVs were examined for cellular proliferation, Lrp5/β-catenin, and bone matrix markers. Bone formation was assessed by micro-computed tomography, calcein injection, and osteopontin expression. Low-density lipoprotein with and without atorvastatin was also tested in AV myofibroblasts for cellular proliferation and regulation of the Lrp5/β-catenin pathway. Our results demonstrate that the cholesterol diet induced complex bone formations in the calcified AVs with an increase in the Lrp5 receptors, osteopontin, and p42/44 expression. Atorvastatin reduced bone formation, cellular proliferation, and Lrp5/β-catenin protein levels in the AVs. In vitro analysis confirmed the Lrp5/β-catenin expression in myofibroblast cell proliferation.

Conclusion—

Hypercholesterolemic AV calcification is attenuated by atorvastatin and is mediated in part by the Lrp5/β-catenin pathway. This developmental pathway may be important in the signaling pathway of this disease.
Abstract 100: Lower Probability of Aortic Aneurysm Diagnosis Among Patients With Chronic Cannabis Exposure, An Analysis of the 2012-2014 National Inpatient Survey
Authors: Adejumo Adeyinka C , Alliu Samson , Adegbala Oluwole M , Onyeakusi Nnaemeka E , Ajayi Tokunbo O , Akinjero Akintunde M , Okafor Adetoro T , Lichstein Edgar
Published: July 2021

Introduction:
Cannabis is a commonly utilized recreational substance which contains numerous bioactive agents. As more states legalize the use of marijuana, it’s effect on various disease conditions is expected to become more pronounced. Cannabis’ anti-inflammatory effects could suppress pro-inflammatory conditions. For example, chronic inflammation with extracellular matrix degradation resulting in weakness and abnormal dilatation of the aortic wall is a hallmark of Aortic Aneurysm. We, therefore, hypothesized that cannabis users would have less prevalence of aortic aneurysms.

Objective:
To identify the relationship between chronic cannabis use (CU) and diagnosis of aortic aneurysms (AA) among hospitalized patients.

Methods:
After selecting patients who were 55 years and above from 2012 to 2014 National Inpatient Sample database, we identified those who had a diagnosis of Aortic Aneurysm and those who utilize Cannabis. We then stratified the CU into two groups: nondependent (NDU) and dependent users (DU). Using logistic regression, we estimated the Odds Ratio (AOR) after controlling for numerous factors.

Results:
In our total 10,461,694 sample, 99.6% (10,419,972) are non-users, 0.37% (38,514) are nondependent users and 0.03% (3,208) are dependent users. About 3.21% (336,202) of the patients had a diagnosis of AA versus 96.79% (10,125,492) without a diagnosis of AA. Compared to non-users of cannabis, the odds of AA is about 35% less among CU (AOR 0.66[0.62-0.71]), 40% less among DU (aOR 0.58[0.44-0.76]), and 33% less among NDU (AOR 0.67[0.62-0.72]). The odds of AA was lower in females (AOR 0.61[0.60-0.610]), but higher in many conditions such as: among >=65 years (AOR 1.16[1.15-1.17]), tobacco users (AOR 1.18[1.17-1.19]), predisposing hereditary conditions (AOR 5.31[4.60-6.13]), and atherosclerosis (AOR 3.04[3.00-3.08]).

Conclusions:
Our result shows that Cannabis use is associated with less occurrence of AA. Cannabidiol, an anti-inflammatory alkaloid in Cannabis could potentially suppress the release of proteolytic inflammatory mediators which might be responsible for the gradual weakening of the vascular walls. We recommend more basic research to evaluate this effect of Cannabidiol.
Abstract 104: Prevalence of Abdominal Aortic Aneurysm in Multi-Vessel Coronary Artery Disease
Authors: Kadakia Rikin , Parashar Amitabh
Published: July 2021

Background:
Abdominal aortic aneurysm (AAA) is the 10
th
leading cause of death in the United States. USPSTF recommends screening for AAA on men ages 65 to 75 years who have ever smoked. However, recent literature suggests an increased prevalence of AAA in patients with multi-vessel coronary artery disease (CAD) irrespective of age. Additionally, CAD with AAA share common risk factors. AAA rupture or repair on patients less than 65-year-old have not been documented.

Objective:
We conducted a single center retrospective review of all patients at the Salem VA Medical Center, Virginia who completed an abdominal ultrasound (US) for AAA screen in 2013. The goal of the current study was to identify the prevalence of AAA through routine US screen in veteran population compare with the prevalence of AAA in patients with multi-vessel CAD. Additionally to identify specific trends in high-risk population.

Method:
Cohort A included 634 patients for primary screening of AAA. Cohort B included 132 patients who had multi-vessel CAD based on coronary catherization were reviewed for incidental AAA on any abdominal imaging. Medical records were reviewed; demographics were collected including age, gender, HTN, DLD, DM, tobacco use, presence of AAA, and size.

Conclusion:
Cohort B had 19.3% (26/135) prevalence of AAA, verses Cohort A had 7.7% (49/634), a statistically difference P (0.008). Cohort B, 13.3% (6/26) were less than 65-years-old verses 25% (20/88) were over 65 years old. Cohort A with AAA 34.5% (17/49) of patients had documented CAD - Number of coronary vessels conferred to a greater risk of AAA, 2 vessel CAD 10.3% (6/58), 3 vessel CAD 7.3% (10/73), 4 vessel CAD 100% (1/1). This result supports the growing concern for AAA in patients with multi-vessel CAD, thus should be considered as an independent risk factor for AAA. Patients with multi-vessel CAD should be screened sooner than current recommended guidelines.
Abstract 105: Association of Viscoelastic Material Properties and Extracellular Matrix Remodeling in Human Abdominal Aortic Aneurysmal Tissue
Authors: Mix Doran S , Toth Sandra A , Bah Ibrahima , Stoner Michael C , Goldman Bruce I , Buckley Mark , Cameron Scott J , Richards Michael S
Published: July 2021

Objectives:
Predicting rupture of abdominal aortic aneurysm (AAA) requires knowledge of both the rate of extracellular matrix (ECM) degradation and the pulsatile stress on the aortic tissue. The activity of matrix metallopeptidase 9 (MMP9) and its inhibitor, TIMP1, are associated with alterations in aortic ECM but it is unknown if these changes effect the dynamic viscoelastic properties. We hypothesize that increased levels of MMP9 within AAA tissue will be associated with a greater dynamic modulus (E*), as a surrogate of increased aortic wall stress.

Methods:
Human aneurysmal aortic tissue was obtained at the time of open AAA repair (n=11) and age-matched non-aneurysmal cadavers (n=10). Uniaxial viscoelastic material properties were measured in the circumferential orientation under physiologic preload (110 mmHg) and cyclic strain (± 5%@1Hz). Quantitative histologic and immunohistochemistry were preformed using Fiji imaging software. Aortic MMP9 and TIMP1 content and activity were quantified using western blot and zymography.

Results:
E* was greater (1862±464 vs 1362±405 kPa, p=0.02) in the AAA tissue as compared to non-aneurysmal tissue. AAA tissue contained less elastin (6.7±6.7 vs 23.4±8.7%, p=0.01) and a greater collagen/elastin ratio (19.9±20.6 vs 2.3±2.5%, p=0.05). Immunohistochemistry revealed 200% greater MMP9 content in the AAA tissue (Figure A & B, 0.61 vs 0.03%, p=0.03). Increased MMP9 content was confirmed using a western blot (0.43 vs 0.06 AU, p<0.01). No difference in relative MMP9 activity (4307 vs 2324 AU, p=0.25) or level of TIMP1 (0.03 vs 0.02, p=0.6) were observed. There was a positive linear correlation (Figure C, r
2
=0.47) between E* and MMP9 as determined by quantitative immunohistochemistry.

Conclusions:
Our data suggests a positive relationship between E* and MMP9 content. Increased tissue stiffness may trigger MMP9 production resulting in a positive-feedback loop, progressively increasing aortic wall stress and rupture risk.
Abstract 106: Receptor Interacting Kinase 1 Contributes to Pathogenesis of Abdominal Aortic Aneurysm by Causing Smooth Muscle Cell Necroptosis as Well as Inflammation
Authors: Phan Noel M , Zhou Ting , Wang Qiwei , Gupta Kartik , Feldman Conner , Kent K. Craig , Liu Bo
Published: July 2021

Objectives:
Abdominal aortic aneurysm (AAA), the progressive weakening and dilatation most commonly occurred in the infrarenal segment of aorta, is a common aortic disease associated with high lethality. Currently, there is no approved pharmacological treatment to effectively slow aneurysm growth or prevent rupture. We have recently demonstrated that inhibition of receptor interacting protein kinase 1 (RIP1), a critical mediator of necroptosis and apoptosis, attenuates aneurysm pathogenesis in a mouse elastase AAA model. Here, we tested whether RIP1 is also required for aneurysm formation in hypercholesterolemia mice stressed with Angiotensin II (AngII).

Methods:
Apolipoprotein E-deficient mice were infused with 1000 ng/kg/min of AngII for 28 days. The RIP1 inhibitor Necrostatin-1s (Nec-1s, 1.6 mg/kg/day) was administered via daily intraperitoneal (IP) injection. An aneurysm is defined as aortic expansion in the suprarenal ≥50% over infrarenal diameter.

Results:
The incidence of aneurysm formation was significantly lower in Nec-1s treated group compared to the DMSO group (33.35 vs 90.5%). Additionally, Nec-1s reduced aortic expansion (DMSO: 55.40±13.80%, Nec-1s: 121.1±16.44%, p<0.05 unpaired student’s
t
test). The number of mice that died prior to 28 days (due to aortic rupture) were comparable between DMSO and Nec-1 groups. Histological analysis showed preserved elastin fibers in aortae from Nec-1s treatment vs DMSO treatment. Immunohistochemical and immunofluorescence staining revealed that Nec-1s decreased the abundance of CD68+ cells as well as CD3+ T-cells but relative higher number of CD206 positive M2 macrophages in the aneurysm prone aortae. In vitro, Nec-1s attenuated smooth muscle necroptosis but stimulated biosynthesis of elastin. Furthermore, Nec-1s inhibited chemotaxis of monocytes/macrophages.

Conclusions:
Our data demonstrate that RIP1 contributes to aneurysm pathophysiology through regulation of cell death and inflammation infiltration. Being a small chemical molecule that is highly selective for RIP1, Necrostatin-1s may serve as a suitable drug treatment for AAAs.
Abstract 107: Increased Peak Wall Stress in Women With Abdominal Aortic Aneurysms
Authors: Shang Eric , Wang Grace , Fairman Ronald , Jackson Benjamin
Published: July 2021

Objective:
Women with abdominal aortic aneurysms (AAA) exhibit more rapid aneurysm growth and greater rupture risk at equivalent diameters relative to men. Evidence suggests that biomechanical peak wall stress (PWS) derived from finite element analysis of AAAs is a superior predictor of rupture compared to maximum transverse diameter (MTD). This study aimed to investigate differences in the calculated PWS of AAAs between men and women.

Method:
Men (n=35) and women (n=35) with infrarenal AAAs with 45-55mm MTD undergoing CTA were identified. Customized image processing algorithms extracted patient-specific AAA geometries from raw DICOM images. The resulting aortic reconstructions incorporated patient-specific and regionally resolved aortic wall thickness, intraluminal thrombus, and wall calcifications. Aortic models were loaded with 120mmHg blood pressure using commercially available FEA solvers.

Results:
Peak wall stress was found to be significantly higher in women (299±51 vs 257±53 kPA, P=0.001, see Figure). Neither MTD (50.5±3.1 vs 49.8±2.9 mm, P=0.34), mean aortic wall thickness (2.38±0.52 vs 2.34±0.50 mm, P=0.69), nor wall thickness at location of PWS (2.36±0.60 vs 2.20±0.46 mm, P=0.20) varied by sex. While there were no sex-associated differences in aneurysm volume (86.6±27.0 vs 94.8±25.5 cm
3
, P=0.76) or intraluminal thrombus volume (14.2±11.7 vs 16.3±13.4 mm, P=0.33), women’s AAAs had significantly increased maximum Gaussian curvature (0.032±0.011 vs 0.025±0.015 mm
-2
, P=0.03).

Conclusion:
Comparably sized AAAs in women were shown to have significantly higher peak wall stress. Maximum gaussian curvature, a measure of aneurysm morphology, was significantly different between the two groups. These results suggest that men and women possess distinct aneurysm geometries, and that PWS-derived rupture risk prediction may provide a more reliable estimator of rupture risk in all patients.
Abstract 108: Deletion of Lrp1 In SMCS Differentially Alters Susceptibility of Distinct Vascular Beds to BAPN-Induced Aneurysm and Dissection Formation
Authors: Ucuzian Areck A , Catania Selen C , Mukhopadhyay Subhradip , Sarkar Rajabrata , Strickland Dudley S
Published: July 2021

Lysyl oxidase (LOX) inhibition by β-aminopropionitrile (BAPN) induces aortic aneurysm and dissection (AD). The LDL receptor-related protein 1 (LRP1) is an endocytic receptor that plays a key role in maintaining the structural integrity of vessels. Deletion of LRP1 in vascular smooth muscle cells (smLRP1 -/-) in mice induces fully penetrant and spontaneous aneurysms with aging. The objective of this study was to investigate the role of smLRP1 in modulating the susceptibility of various vascular beds to BAPN-induced AD. Wild-type (WT) and smLRP1 -/- mice were treated with BAPN supplemented in drinking water (3g/L). After 4-16 weeks, the vessels were analyzed histologically and with micro-CT. Abnormal elastic lamellae were identified throughout the vasculature of both the BAPN-treated WT and smLRP1 -/- cohorts. smLRP1 -/- mice were more susceptible to aneurysm formation after 8 (p=0.035) or 16 weeks (p=0.043) of treatment. Aneurysms in BAPN-treated WT mice were localized to the aorta, while aneurysms in BAPN-treated smLRP1 -/- mice were localized to the visceral and iliac arteries (Table). Histologic and radiographic evidence of AD was detected in the ascending and descending thoracic aorta in BAPN and AngII (subcutaneous,1μg/kg/min, 24 hrs)-treated WT mice, but not in BAPN and Ang II-treated smLRP1 -/- mice (Figure). Thoracic ruptures were more prevalent in the BAPN-treated WT group and abdominal ruptures were more prevalent in the BAPN-treated smLRP1 -/-group (p=0.02). In summary, these data demonstrate that genetic deletion of LRP1 in SMCs differentially alters the susceptibility of distinct vascular beds to the development of aneurysm and dissection upon LOX inhibition.
Abstract 109: Tumor Necrosis Factor Inducible Gene 6 Protein (TSG-6) is Highly Expressed in Human Abdominal Aortic Aneurysms
Authors: Wang S. Keisin , Green Linden , Xie Jie , Motaganahalli Raghu , Fajardo Andres , Babbey Cliff , McCready Robert , Murphy Michael
Published: July 2021

Objective:
The formation of an abdominal aortic aneurysm (AAA) is characterized by a dominance of pro-inflammatory forces that result in smooth muscle cell apoptosis, extra-cellular matrix degradation, and progressive diameter expansion. Additional defects in the anti-inflammatory response may also contribute to AAA progression, however have yet to be characterized robustly. Here, we describe the role of the anti-inflammatory cytokine TSG-6 (TNF-stimulated gene-6) in AAA formation.

Methods:
Blood and aortic tissue samples were collected from patients undergoing elective AAA screening and open surgical AAA repair. Aortic specimens collected were preserved for IHC or immediately assayed after tissue homogenization. Cytokine concentrations in tissue and plasma were assayed by ELISA. All immune cell populations were assayed using FACS analysis.
In vitro,
macrophage polarization from monocytes were performed with young, healthy donor PBMCs.

Results:
TSG-6 was found to be abnormally elevated in both the plasma and aorta of patients with AAA compared to healthy and risk-factor matched non-AAA donors. We observed the highest tissue concentration of TSG-6 in the less diseased proximal and distal shoulders compared to the central aspect of the aneurysm. IHC localized the majority of TSG-6 to the tunica media with minor expression in the tunica adventitia of the aortic wall. Higher concentrations of both M1 and M2 macrophages where also observed in the aortic wall, however M1/M2 ratios were unchanged from healthy controls. Additionally, we observed no difference in M1/M2 ratios in the peripheral blood of risk-factor matched non-AAA and AAA patients. Interesting, TSG-6 inhibited the polarization of the anti-inflammatory M2 phenotype
in vitro
.

Conclusions:
AAA formation results from an imbalance of inflammatory forces causing aortic wall infiltration of mononuclear cells leading to resultant vessel breakdown. From our results, we suggest TSG-6 is elevated in the AAA patient as a compensatory anti-inflammatory feedback mechanism. However, it’s effects may be abrogated by defects in CD44, its cognate receptor or downstream signaling pathways, future areas for investigation.
Abstract 111: Effect of Thyroxin Treatment on Carotid Intima Media Thickness (CIMT) Reduction in Patients With Subclinical Hypothyroidism (SCH)-A Meta-Analysis of Randomized Clinical Trials
Authors: Kandimalla Yugandhar , Aziz Muhammad , Machavarapu Archana , Malik Rehan , Younus Adnan , Jaffe Aaron , Jaber Rana , Choudhry Huwad , Ronderos Samantha , Paz Nadia , Veledar Emir , Nasir Khurram
Published: July 2021

Background:
Research shows that subclinical hypothyroidism (SCH) is related to increased carotid intima media thickness (CIMT), a surrogate marker of stroke and subclinical cardiovascular disease (CVD). It is controversial whether SCH should be treated or not to reduce risk of stroke and CVD morbidity and mortality. The aim of this meta-analysis was to determine whether SCH is associated with an increase in CIMT as compared to Euthyroidism (EU) and whether thyroxin therapy in SCH can reverse the change in CIMT.

Methods:
Two independent reviewers did an extensive database search up to December 2016. Total of 12 randomized clinical trials discussed effect of thyroxin treatment on CIMT values at pre-and-post treatment in SCH subjects.

Results:
CIMT was significantly higher among SCH (n=280) as compared to EU controls (n=263) at baseline, pooled standardized mean difference (SMD) of CIMT was 0.44 mm [95%CI 0.14, 0.74], SE=0.15; p=0.004 with heterogeneity I
2
= 65%. After treatment with thyroxin in SCH subjects (n=314), there was a statistically significant decrease in CIMT from pre-to-post treatment, pooled SMD of CIMT decrease was [SMD -0.32; 95%CI (-0.47, -0.16), SE=0.08; p<0.0001, with heterogeneity I
2
= 2%], and was no longer different from EU controls [SMD 0.13 mm; 95% CI (-0.04, 0.30); p= 0.14; I
2
= 27%]. The total cholesterol, triglycerides, and low density lipoprotein were higher in SCH as compared to EU controls and decreased significantly after treatment with thyroxin.

Conclusion:
This meta-analysis shows that thyroxin therapy in SCH subjects significantly decreases CIMT and improves lipid profile, modifiable risk factors for stroke and CVD. Thyroid hormone replacement in SCH subjects might have a role in slowing down or preventing progression of atherosclerosis.
Abstract 114: Calf Muscle Oxygen Saturation During Standardized Treadmill Testing in Patients With Intermittent Claudication
Authors: Hernandez Hernan , Schieber Molly , DeSpiegelaere Holly K , Brunette Katyarina E , Kim Kyung-Soo , Mietus Constance , Baker Sarah , Myers Sara , Casale George P , Pipinos Iraklis
Published: July 2021

Objectives:
Leg muscle hypoxia during walking is believed to be a key mechanism underlying the exercise intolerance of claudicating patients but detailed data on the changes exercise produces in the kinetics of leg muscle oxygenation are limited. Our objective was to record the calf muscle oxygen saturation (MO
2
S) at rest, during treadmill exercise and during recovery from exercise in patients with chronic claudication.

Methods:
We recruited 19 claudicating patients. The MO
2
S of the gastrocnemius was recorded with the Moxy near-infrared spectroscopy monitor (Hutchinson, MN). We measured resting MO
2
S for a period of three minutes and then performed a Gardner, standardized treadmill test. We recorded claudication onset time (COT) and peak walking time. We also measured the MO
2
S recovery for 30 minutes following the end of the TT or until muscle saturation reached a steady state.

Results:
Table I summarizes our results. Patients started experiencing a decrease in their MO
2
S 18.8 sec after initiation of TT; approximately 28 steps covering 16.8 meters. COT occurred when calf MO
2
S had dropped to 23.7%. Patients reached their minimum (14.1%) MO
2
S, 340.5 sec into the TT. During the post-TT recovery period, MO
2
S rebounded initially to 65.1% at 689.4 sec and 407.1 sec later it declined to a steady-state level of 56.3%, both above the pre-TT baseline reading. This relative hyperoxic state persisted for the duration of the post-exercise recording period (≥30 min).

Conclusions:
Our study objectively demonstrates considerable, walking-induced changes in MO
2
S in patients with claudication. During walking, MO
2
S drops quickly and the calf muscles experience substantial hypoxia while after the end of walking, MO
2
S rebounds above the baseline state and the leg muscles remain relatively hyperoxic beyond 30 min. This study provides much needed data concerning the kinetic patterns of muscle oxygenation claudicating patients experience in their everyday lives.
Abstract 115: Microvascular Response to Ramipril in Peripheral Artery Disease
Authors: Mietus Constance J , Karvelis Peter , Lackner Timothy , Hernandez Hernan , DeSpiegelaere Holly , Xie Feng , Porter Thomas , Pipinos Iraklis , Casale George P
Published: July 2021

Background:
The myopathy of Peripheral Artery Disease (PAD), a consequence of ischemia caused by atherosclerotic plaques in arteries supplying the legs, is characterized by myofiber degeneration and fibrosis of the vascular walls and extramyofiber matrix. In association with fibrosis we have found a robust expression of the profibrotic cytokine TGFβ1 in vascular smooth muscle cells. Additionally, we have observed microvascular endothelial “swelling” in PAD muscle. Published data indicate that inhibitors of the angiotensin system reduce fibrosis in multiple organ systems and improve walking performance, in diverse patient populations. We hypothesize that “swelling” of microvasculature endothelial cells represents abnormal accumulation of basement membrane Collagen Type IV (Col-IV) and that treatment with Ramipril will improve the microvasculature.

Methods and Results:
Gastrocnemius biopsies of PAD patients at Fontaine Stage II (N=5) before and after six months of Ramipril intervention and control patients (N=4) were labeled with an antibody specific for Col-IV. Images were acquired with an automated wide-field microscope and then processed with Image Pro Plus® and AutoQuant® deconvolution software. We used Col IV label to measure wall thickness and lumen diameter of 230 to 360 microvessels per patient, with a custom MatLab program based on the Expectation Maximization algorithm coupled with a Gaussian Mixture Model. Microvessel wall thickness was significantly greater (p < 0.04) in PAD patients before (1.54 ± 0.04 μ) and after (1.61 ± 0.06 μ) Ramipril treatment compared to control (1.42 ± 0.02). Lumen diameter was significantly greater (p < 0.02) in Post-Ramipril (3.49 ± 0.04 μ) compared to Pre-Ramipril (3.18 ± 0.08 μ) and control (3.00 ± 0.11 μ) patients.

Conclusions:
The increase of microvessel lumen diameter with Ramipril treatment is expected to increase microvascular perfusion and thereby improve walking distance. Our study will be expanded to increase cohort size and evaluate the association of microvascular measurements with microperfusion determined by Contrast Enhanced Ultrasonography and with walking performance.
Abstract 119: Protective Effects of Chloroquine on Ischemic and Nutrient Depleted Muscle are Mediated by HMGB1 and Caspase-1
Authors: Sachdev Ulka , Cui Xiangdong , Sun Qian , Tzeng Edith , Chen Alex , Scott Melanie
Published: July 2021

Introduction:
Millions of Americans are at risk for amputation from severe peripheral arterial disease (PAD) when surgery is not possible. Pro-regenerative and angiogenic agents may improve outcome in that setting. Chloroquine (CQ) promotes wound healing in scleroderma but has not been tested in PAD. CQ promotes healing of ischemic muscle, increases muscle high mobility group box 1 (HMGB1), an inflammatory, pro-angiogenic protein, and activates caspase-1 in myoblasts. We hypothesize that HMGB1 mediates protective effects of CQ and is regulated by caspase-1 in muscle. Controlled rather than indiscriminate release of HMGB1 from damaged muscle may be protective during ischemia.

Methods:
C2C12 myoblasts in low serum were treated with CQ (0-50μM) ± Ac-YVAD-cmk (10 μg/ml), a caspase-1 inhibitor. HMGB1 release in supernatants was measured using ELISA. Cytotoxicity was assessed by comparing spontaneous lactate dehydrogenase (LDH) activity in culture media from control, treated and maximally lysed cells. CQ (50μg/ml) or placebo treated wild-type and inducible HMGB1 knockout (iHMGB1KO) mice underwent unilateral femoral artery ligation (FAL). Laser Doppler perfusion imaging (LDPI) before and 1,7,14 and 21d after FAL was reported as % improvement over time. ANOVA was used to assess statistical significance among groups.

Results:
CQ (5-10uM) attenuated spontaneous LDH leak after 12h from serum-depleted myoblasts (p <0.01, N=3), and modestly increased HMGB1 release (p <0.001, N=3). Ac-YVAD-cmk reversed the cytoprotective effects of CQ, significantly raising both LDH activity to 55% of maximal activity and HMGB1 in the supernatant. Compared to d1 post FAL, CQ improved perfusion recovery in WT mice by 300-800% over 21 days (p<0.03, N=7/group), but not in iHMGB1KO mice.

Conclusion:
We present the novel finding that in nutrient-depleted myoblasts, caspase-1 mediates the survival benefits of CQ and regulates HMGB1 release. In turn, HMGB1 is critical for CQ’s beneficial effects on perfusion after FAL, another stress condition. Regulated HMGB1 release may be immunomodulatory, regenerative and modifiable with drugs like CQ. Altering survival and inflammatory pathways through CQ may present a novel therapeutic strategy in PAD.
Abstract 12: Volume of Calcium in the Descending Thoracic Aorta Predicts All Cause Mortality Beyond Coronary Artery Calcium: The Multi-Ethnic Study of Atherosclerosis
Authors: Thomas Isac C , Allison Matthew A , Forbang Nketi I , Michos Erin D , Longstreth WT , Wong Nathan , Post Wendy , Criqui Michael H
Published: July 2021

Introduction:
Coronary artery calcium (CAC) volume and density differentially predict incident cardiovascular disease (CVD), with CAC density inversely associated with these outcomes. Whether similar associations exist between descending thoracic aortic calcium (DTAC) volume and density and all cause mortality (ACM) are unknown. We hypothesized that DTAC volume and density predict ACM independently of CAC.

Methods:
The Multi-Ethnic Study of Atherosclerosis enrolled 6,814 participants free of clinical CVD at baseline and followed them for incident adverse events. Cardiac CT at baseline visualized the segment of the descending thoracic aorta posterior to the heart. Only participants with prevalent DTAC were included (necessary to evaluate DTAC density). DTAC and CAC volumes were natural log transformed to adjust for skewness. Cox regression models estimated the associations of DTAC volume and density with ACM after adjustment for age, gender, ethnicity, CVD risk factors, statin use, and CAC volume and density. The incremental predictive values of DTAC volume and density were evaluated by area under receiver operating characteristic (AUC) curves.

Results:
Of the total cohort, 1,850 participants (27%) had prevalent DTAC and 491 deaths occurred over 10.3 years. In separate regression models, DTAC
volume
was independently associated with ACM after adjustment for CAC volume (HR 1.21 [95% CI 1.09-1.35]) and additional adjustment for CAC density (1.18 ([1.06-1.32]). After the same adjustments, DTAC
density
was not significantly associated with ACM (0.94 [0.84-1.06]). The AUC for the base Model 1 (risk factors + CAC volume) was 0.706 (0.680-0.732), which increased to 0.716 (0.690-0.742) with the addition of DTAC
volume
in Model 2 (p=0.03 compared to Model 1). Further addition of DTAC
density
in Model 3 did not improve the AUC significantly (0.717 [0.692-0.743], p=0.23 compared to Model 2).

Conclusions:
In a cohort free of baseline clinical CVD, DTAC visualized on cardiac CT was common. When DTAC was present, DTAC volume (but not density) was independently associated with ACM. DTAC volume also significantly improved ACM risk prediction beyond risk factors and CAC volume.
Abstract 121: Role of Oxidative State in Endothelial Cells During Arteriogenesis
Authors: Shrestha Bandana , Pattillo Christopher B
Published: July 2021

Peripheral vascular disease (PVD), a common cardiovascular disease causes reduced blood flow to the limbs, ischemia related complications and in severe cases amputations. Atherosclerotic plaque formations result in ischemia from gradual occlusion of blood vessels followed by shunting of blood through collateral arteries increasing their arteriolar size for perfusion compensation (arteriogenesis). This change in shear flow and friction in the surrounding arteries and vasodilation affects the underlying blood vessels thereby activating signaling pathways including VEGFR2, NO and NF-κB, increased inflammation and remodeling of endothelial and smooth muscle cells. However, this important compensatory mechanism is affected adversely due to increased oxidative stress which leads to defective arteriogeneis and worsened PVD complications. Typically, antioxidants such as glutathione (GSH) regulates the oxidative stress within cells by reducing Reactive Oxygen Species (ROS) while being oxidized into glutathione disulfide (GSSG), hence maintaining an optimum GSH:GSSG ratio. Our experiments with arterial ligation models using transgenic mice with modified Gclm (modulatory subunit of an enzyme for GSH synthesis) showing Gclm-/- (KO) mice having severely diminished GSH levels (~80%), Gclm +/- (HET) mice having slightly decreased (~20%) and wild type mice with highest levels of GSH implicate a delicately balanced ratio (as seen with Gclm+/- mice) to increased blood flow and reperfusion, an important regulation during arteriogenesis. Additionally, GSH:GSSG levels can lead to post translational modification such as cysteine glutathionylation which is known to protect cysteine residues from oxidation as well as regulate the function of various proteins. Our studies in Human Aorta Endothelial cells (HAECs) have implicated a relationship between varying GSH:GSSG ratios, resulting glutathionylation and VEGFR2 phosphorylation, an important player in arteriogenesis. Hence, a critical balance between the reductive and oxidative cellular environments drives optimal VEGFR2 signaling to mediate arteriogenic remodeling due to increased shear and oxidant stress.
Abstract 13: Inhibition of Nudt6 Stabilizes Advanced Atherosclerotic Plaques
Authors: Jin Hong , Li Yuhuang , Chernogubova Ekaterina , Bäcklund Alexandra , Sellberg Stina , Sun Changyan , Busch Albert , Eken Suzanne M , Perisic Ljubica , Hedin Ulf , Tsantilas Pavlos , Eckstein Hans-Henning , Pelisek Jaroslav , Maegdefessel Lars
Published: July 2021

Natural antisense transcripts (NATs), a non-coding RNA subclass, being transcribed in antisense direction to protein coding genes, are an intriguing novel class of targetable modulators, exerting crucial effects on gene expression. Aim of the current study was to investigate the contribution of NATs to atherosclerotic plaque vulnerability.

Using laser capture micro-dissection, we isolated fibrous caps tissue of carotid artery plaques from 20 symptomatic patients with ruptured lesions
vs.
20 samples from asymptomatic patients with stable lesions. A human transcriptome array (HTA;
GeneChip 2.0
) was used to profile the expression of all currently annotated RNA transcripts. Nucleoside diphosphate-linked moiety X motif 6 (NUDT6) was identified as one of the most significantly up-regulated transcripts in fibrous caps of ruptured lesions. Interestingly, NUDT6 is an established antisense RNA targeting the fibroblast growth factor 2 (FGF2). Of importance, FGF2 was among the most significantly down-regulated transcripts in ruptured lesions, corresponding to elevated NUDT6 expression.

In situ
hybridization in both, human and mouse carotid atherosclerotic plaques, confirmed substantially higher expression levels of NUDT6 in ruptured lesions compared to stable. In addition,
in situ
hybridization revealed a distinct co-localization with smooth muscle cells (SMCs) in advanced plaques. Overexpression of NUDT6 in cultured human carotid artery SMCs effectively limited FGF2 on the mRNA as well as protein level. Furthermore, reduction of NUDT6 via siRNA stimulated proliferation and blocked apoptosis in SMCs. In an inducible atherosclerotic plaque rupture model using incomplete ligation and cuff placement on common carotid arteries of male
apoE
-/- mice, NUDT6 inhibition with gapmeRs was able to significantly improve SMC survival rates, leading to thicker fibrous caps, and to reduce the plaque rupture rate compared to scramble-gapmeR control-treated mice (22%
vs
. 63%,
p
= 0.03).

The present study presents NUDT6 as a novel crucial antisense regulator of fibrous cap stability through steering SMC survival
via
targeting its sense RNA transcript FGF2.
Abstract 130: The Diversity of Coronary Artery and Myocardial Infarction in Mice
Authors: Chen Jiqiu , Ceholski Delaine K , Liang Lifan , Hajjar Roger
Published: July 2021

Low reliability and reproducibility in heart failure research has been a major concern. The purpose of the present study is to explore factors that affect model consistency of myocardial infarction (MI) in mice.

Methods:
MI was induced by left coronary artery (LCA) ligation. Echocardiography was used to measure cardiac function after MI. The coronary artery was casted with resin and visualized with fluorescent imaging in ex vivo. LCA characteristics and MI size were analyzed individually in each animal. MI size was correlated with LV function by echocardiography.

Results:
Coronary anatomy varies widely amongst animals, posing challenges for surgical ligation and resulting in inconsistent MI size data post-ligation. The length of coronary arterial trunk, level of bifurcation, number of branches, and territory supplied by these branches were unique in every animal. When the main LCA trunk was ligated, this resulted in a large MI, but when a single branch was ligated, MI size varied significantly due to differing levels of LCA ligation and differing amounts of territory supplied by the branches. During the ligation procedure, nearly 40% of LCAs were not grossly visible to the surgeon. In these situations, the surgeon commonly blindly sutures a wider and deeper area of tissue in an attempt to ensure that the LCA is caught and ligated. Paradoxically, these situations have greater odds of resulting in smaller MIs.

Conclusion:
The current study offers evidence of anatomical LCA diversity and the problems this poses for creating a consistent heart failure model by LCA ligation in mice. Carefully recognizing the inevitable individual variation of coronary anatomy in mice is essential to restoring reliability of the LCA ligation model of heart failure.
Abstract 131: Could One Define "FARD Score (Female, Aging, Respiratory & D-Dimer)" in Regard to Deep Vein Thrombosis in Cases With Immobilization?
Authors: Sato Koichi , Hanzawa Kazuhiko , Okamoto Takeshi , Nagasawa Ayako , Aoki Kenji , Namura Osamu , Tsuchida Masanori
Published: July 2021

Objectives:
With 17 sub-analyses, this prospective study aimed at evaluating the prevalence and indicators of deep vein thrombosis (DVT) associated with pulmonary embolism (PE) in patients immobilized on admission to internal medical wards.

Methods:
In sub-groups (with more than 20 cases) of the 189 consecutive patients immobilized for more than 48 hours after admission (screening), we studied the significance of the major clinical factors in relation to whether DVT was identified with ultrasonography. If D-dimer level was positive (≥ 1.0 μg/ ml) in each case, chest enhanced CT was performed.

Results:
With regard to 16 PE cases (8.5%) of the 189 cases, incidence of PE was higher in the groups of
elderly
patients (14%, 9 of 63 cases), of
women
(12%, 13 of 111 cases) and of patients with
respiratory
disease (9%, 3 of 33 cases) than in the other sub-groups. Among 77 DVT cases (40%) of the 189 cases, the groups of patients with
respiratory
disease (13 DVT cases), with gastro-intestinal disease (13 DVT cases) and with renal disease (13 DVT cases) included respectively more than those with the other diseases, in addition to the group of patients with malignant disease (15 DVT cases). In the groups of patients with abdominal disease (52%, 14 of 27 cases), central venous catheter (50%, 12 of 24 cases) and
advanced age
(49%, 31 of 63 cases), ratios of DVT cases were higher than in the other sub-groups. In patients with renal disease (P=0.01) and in
women
(P=0.02),
D-dimer
level was higher in DVT cases than in non-DVT cases whereas, in the groups with abdominal disease (P=0.72) and with respiratory disease (P=0.49),
D-dimer
level was essentially comparable between in DVT cases and in non-DVT cases. Only in the group of
elderly
patients, the prevalence of DVT was higher above-knee than below-knee. Multiple presence of DVT (20 of 77 DVT cases) was associated with presence of pulmonary embolism (P=0.09) in DVT cases.

Conclusions:
In DVT cases with immobilization, practical risk factors of pulmonary embolism could be Female, Aging (older than 70 years, classified possibly), Respiratory disease and, in women, high D-dimer level.
Abstract 132: Glomerular Podocyte Damage is Mitigated by Normal HDL and ApoA1
Authors: Tsuchida Yohei , Zhong Jianyong , Anantharamaiah G.M. , Linton MacRae , Yang Haichun , Kon Valentina
Published: July 2021

We and others have shown that chronic kidney disease (CKD) disrupts the normally beneficial effects of apoAI/HDL on many different cell types. Proteinuria which characterizes CKD is a hallmark of glomerular podocyte injury and a powerful risk factor for cardiovascular disease (CVD). Although the glomerular filtration barrier normally limits direct contact of lipoproteins with podocytes, disruption in the filtration barrier promotes such interactions. We therefore investigated the effects of normal HDL and ApoAI on injured podocytes and compared these effects to HDL isolated from subjects with CKD.

Primary podocytes were isolated from wild type mice. The cells were exposed to puromycin (PAN, 100ug/ml) with and without HDL isolated from controls with normal kidney function, individuals with CKD, normal ApoA1 (EMD Millipore Company), and ApoA-I mimetic peptide L-4F. We assessed podocyte viability and proliferation (colorimetrically), cellular production of superoxide (ROS)(HPLC), membrane lipid rafts, phosphorylated caveolin-1 (Cav-1)(western blot).

PAN significantly altered ROS production, cell viability, proliferation. ApoA1 or HDL
Cont
, but not HDL
CKD
, significantly improved each of these responses. In addition, L-4F increased podocyte viability (0.60±0.04 PAN vs 0.65±0.04 PAN+L-4F) and HDL
Cont
, but not HDL
CKD
, normalized the significant increase in PAN-induced Cav-1 phosphorylation (0.65±0.04 vs 0.81±0.05 vs 0.70±0.09, respectively).

We conclude that podocyte damage including ROS production, cellular membrane and functions can be mitigated by normal HDL or its primary lipoprotein, ApoA1, findings that parallel beneficial functions of HDL/ApoA1 on other cell types. By contrast, HDL of subjects with CKD do not provide similar benefit.