bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 5364: Vitamin B1 Analogue Benfotiamine Supplementation Prevents Diabetic Cardiomyopathy through Activation of eNOS/Akt Signaling Pathway
Authors: Katare Rajesh , Meloni Marco , Caporali Andrea , Emanueli Costanza , Madeddu Paolo
Published: July 2021

Cardiomyopathy (DCM) is increasingly recognized as contributing to mortality and morbidity of diabetic patients. Importantly, initial signs of cardiac dysfunction are detected in 75% of young patients with well controlled diabetes, suggesting the necessity for early prevention. Vitamin B1 is defective in diabetics and supplementation with vitamin B1 analogue Benfotiamine (BFT) has been demonstrated to be protective against experimental diabetic limb microangiopathy, nephropathy and retinopathy. Here, we tested whether supplementation of BFT could exhibit its protective effects against DCM. Streptozocin-induced CD1 diabetic (DM) mice were fed with BFT (70mg/kg/day) or vehicle starting from 2wks after glycosuria documentation. Cardiac function was monitored every month using Vevo high resolution echocardiography. 12wks after DM induction, the animals given vehicle started developing the signs of diastolic and systolic dysfunction which was more significant at 20wks of DM. However, BFT (without insulin supplement) markedly suppressed the DM induced left ventricular cavity dilatation (LV end-diastolic volume; 61±4 vs 74±5μl, p<0.001), improved fractional shortening (40±4 vs 26±4%, P<0.001) and ejection fraction (72±5 vs 54±4%, p<0.001) and shifted pressure volume loop leftward compared with the vehicle treated animals. BFT also improved indexes of systolic and diastolic function (dp/dt
max
5886±400 vs 4730±356mmHg/s and dp/dt
min
3963±282 vs 3145±284mmHg/s, P<0.05 for both comparison). Further, BFT benefited cardiac perfusion (4.5±0.4 vs 3.8±0.1ml/min/gm of tissue, P<0.01, using fluorescent microspheres), which was supported by increased microvasculature (4332±321 vs 3654±263 capillaries/mm
2
). Moreover, BFT (150μM) reduced the high glucose (30mM) induced apoptosis of cultured adult cardiomyocytes by 21±4% (P<0.05) through activation of the cell survival Akt and eNOS pathway, suggesting its direct effect on cardiomyocytes. Altogether, these results demonstrate that BFT supplementation protects the heart from DM induced cardiac dilatation and dysfunction through activation of prosurvival mechanisms and preservation of myocardial perfusion. Thus, BFT merits attention for potential application in clinical practice.
Abstract 5372: In Vivo Myocardial Distribution of Adult Stem Cells Immediately Following Intracoronary Delivery in a Swine Model of Myocardial Infarction
Authors: Ly Hung , Hoshino Kozo , Pomerantseva Irina , Kawase Yoshiaki , Yoneyama Ryuichi , Takewa Yoshiaki , Vooght Carrie , Frangioni John V , Hajjar Roger J
Published: July 2021

Background: Cardiac cell-based therapy (CCT) has emerged as a promising therapeutic strategy. There are few data comparing the fate of different stem cell (SC) populations delivered by the intracoronary injection (ICI).

Aim: Document the in vivo myocardial distribution of SC delivered by ICI following recent myocardial infarction.

Methods: In a myocardial infarction swine model, near-infrared (NIR) fluorescence was used to provide high sensitivity in vivo tracking of SC in the immediate phase (< 60 minutes) after ICI of 2x107 cells. After labeling with the NIR fluorophore, IR-786, the NIR signal intensities and myocardial distribution patterns of mesenchymal (MSC), bone marrow-(BMMNC) and peripheral blood-mononuclear (PBMNC) cells were compared using an open-chested fluorescence imaging system.

Results: The SC populations of interest were successfully loaded with IR-786. While all SC populations readily distributed along the vascular territory of the infarct-related artery immediately after injection, there was a mean SI intensity drop of 29.8% and 14.1% for PBMNC and BMNC (p<0.05), respectively, which correlated with poor cell retention. No significant SI change was found in MSC-injected swine, which was associated with less cell loss after delivery. There was also evidence of MSC-related vessel plugging in some swine (Figure

).

Conclusion: Our in vivo findings suggest that immediately after injection (during the first 60min ICI), there is already evidence of poor SC retention and distribution vary depending on cell population, potentially impacting clinical efficacy and safety of CCT.
Abstract 5381: Insulin-Stimulated Glucose Oxidation is Increased in Hearts from High Fat Diet-Induced Obese Mice Lacking Malonyl CoA Decarboxylase
Authors: Ussher John Edward R , Koves Timothy R , Jaswal Jagdip S , Newgard Christopher B , Dyck Jason R , Muoio Deborah M , Lopaschuk Gary D
Published: July 2021

OBJECTIVE -
Diet-induced obesity (DIO) leads to an accumulation of intra-myocardial fatty acid metabolites that have been proposed to cause myocardial insulin resistance and dysfunction. Our goal was to determine the effect of DIO on myocardial fatty acid metabolite accumulation and how this is altered when mitochondrial fatty acid uptake is inhibited. This was achieved by using mice lacking malonyl CoA decarboxylase (MCD−/−), which have higher levels of malonyl CoA, an endogenous inhibitor of mitochondrial fatty acid uptake.

METHODS -
Wild type (WT) and MCD−/− mice were fed a low (4% kcal from lard) or high (60% kcal from lard) fat diet for 12 weeks to determine the effect of DIO on the intra-myocardial accumulation of long chain acylcarnitines, long chain acyl CoAs, triglycerides (TGs), and ceramides. A parallel feeding study was performed to assess myocardial function and energy metabolism in isolated working hearts in the absence/presence of insulin.

RESULTS -
We demonstrate that MCD−/− mice do not accumulate intramyocardial long chain acylcarnitines to the same extent as WT mice following DIO (0.56 ± 0.10 vs. 0.28 ± 0.07 pmol myristoylcarnitine/mg protein,
P
<0.05), but do accumulate similar amounts of long chain acyl CoAs (3.88 ± 0.34 vs. 4.35 ± 1.19 nmol/g wet weight). Interestingly, DIO only lead to an accumulation of TGs in the hearts of MCD−/− mice (3.29 ± 0.62 vs. 10.92 ± 3.72 μmol/g wet weight,
P
<0.05). Despite this elevation in TGs, MCD−/− mice showed increased insulin-stimulated glucose oxidation (2.46 ± 0.25 vs. 1.74 ± 0.18 fold increase,
P
<0.05) during aerobic isolated working heart perfusions and did not elicit any dysfunction.

CONCLUSIONS -
Our data reveal discordance between myocardial TG accumulation and glucose metabolism, suggesting that TG buffers against toxic lipids, and that inhibition of mitochondrial fatty acid oxidation does not cause myocardial dysfunction following DIO.
Abstract 5394: H11 Kinase/Hsp22, A Novel Mechanism in the Transition to Heart Failure
Authors: Qiu Hongyu , Hong Chull , Gao Shumin , Vatner Dorothy E , Vatner Stephen F , Depre Christophe
Published: July 2021

H11 kinase/Hsp22 (H11K), a heat shock protein expressed mainly in the heart, is up-regulated upon pressure overload in animal models and in patients. Cardiac-specific over-expression of H11K in a transgenic model induces cardiac hypertrophy with normal function and cardioprotection against lethal ischemia. We tested the hypothesis that H11K deletion would accelerate the transition into heart failure (HF) following chronic pressure overload. An H11K knockout (KO) mouse was generated, which survives after birth with normal Mendelian distribution. In basal conditions (4/group), no differences were found between KO and wild type (WT) in terms of left ventricular (LV) mass (LV/tibial length: 4.6±0.3 vs 4.1±0.1, NS) or LV ejection fraction (69±3% vs 70±1%, NS). After two weeks aortic banding the KO mice, compared to WT, showed a slightly greater mass (LV/tibial length: 8.2±0.3 vs 7.0±0.4, P<0.05), impaired LV function (LV ejection fraction: 45±3% vs 62±5%, P<0.05), and signs of HF (lung weight/TL: 16.2±3 vs 7.7±0.4, P<0.05; LV end-diastolic pressure: 22±4 mmHg vs 7±4 mmHg, P<0.05). To test whether H11K participates in cardiac cell survival, both WT and KO mice were submitted to 30 min no-flow ischemia of the left anterior descending artery followed by 24 hours reperfusion and staining for the area-at-risk (AAR) and infarct size (IS). Whereas AAR was comparable between groups, the IS/AAR was more than doubled (P<0.01, n=3/group) in KO (61±2.8%) compared to WT (26±2.8%). Therefore, H11K deletion does not affect basal cardiac function but it precipitates the transition into HF following pressure overload, potentially by loss of H11K cardioprotective action.

This research has received full or partial funding support from the American Heart Association, AHA National Center.
Abstract 5396: The Role of the Myeloid-Related Protein 8/14 Complex in Postischemic Heart Failure
Authors: Volz Christian , Lasitschka Felix , Eichberger Sebastian N , Kaya Ziya , Autschbach Frank , Pleger Sven , Bierhaus Angelika , Remppis Andrew , Katus Hugo A , Andrassy Martin
Published: July 2021

The complex formed by two members of the S100 calcium binding protein family, myeloid-related protein complex 8/14 (MRP8/14) exerts pro-inflammatory and pro-apoptotic activity against various cells. Since enhanced MRP8/14 serum levels have recently been associated with acute coronary syndromes (ACS) this study sought to identify the pathophysiological relevance of MRP8/14 in the development and progression of postischemic heart failure (HF). Here we demonstrate that MRP8/14 acts as an early mediator of inflammation and organ damage in I/R injury of the heart via the receptor for advanced glycation end products (RAGE). Wildtype (WT) and RAGE
−/−
mice were subjected to myocardial infarction by transient ligation of the left anterior descending (LAD) coronary artery and survival, infarction size, cardiac function and remodeling were analyzed up to 4 weeks. Both cardiac RNA and protein levels of MRP8/14 were already elevated 30 minutes after hypoxia
in vitro
and in ischemic heart with sustained activation up to 28 after ischemic injury. Treatment of mice with recombinant MRP8/14 resulted in increased infarction sizes (70.5±4.5% vs. 57.0±4.3%, n=10, p<0.001) determined after 7 days and reduced cardiac performance in echocardiography after 28 days following I/R injury (18.4±2.1% vs30.6%±3.6, n=10, p<0.001). Moreover treatment with MRP8/14 resulted in an accelerated transition to HF, rapid onset of remodelling and excessive mortality compared to untreated WT-mice with ischemic injury. Signaling studies in isolated ventricles point to the involvement of the MAP kinases JNK, ERK1/2 as well as the nuclear transcription factor NF-κB in ischemic heart failure. Interestingly, infarct size, markers of tissue damage and remodelling were not affected by administration of MRP8/14 in RAGE
−/−
mice which demonstrated significantly reduced cardiac tissue damage and improved cardiac recovery compared to WT mice. Our novel proof-of- concept study provides evidence that the sustained activation of S100A8/9 critically contributes to the development of postischemic heart failure via RAGE potentially driving the progressive course of patients with HF.
Abstract 5398: Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) Supplementation, but not α-Linolenic Acid, Elevates Plasma Adiponectin Concentration and Prevents Pressure Overload Induced Ventricular Dysfunction and Remodeling
Authors: Duda Monika K , Xu Wenhong , Tintinu Anselm , O’Shea Karen M , Stanley William C
Published: July 2021

Coronary disease is reduced by intake of the ω-3 polyunsaturated fatty acids (ω-3PUFA) EPA and DHA. Recent evidence suggest EPA+DHA may also prevent development of heart failure. We previously showed that intake of fish oil rich in EPA+DHA up-regulates expression and plasma levels of adiponectin, a cardioprotective adipose-derived hormone. We examined the effects of dietary EPA+DHA on plasma adiponectin levels and development of left ventriclular (LV) dysfunction and remodeling in response to pressure overload induced by abdominal aorta banding. Rats were fed either a standard chow or diets supplemented with EPA+DHA from fish oil at 0.7%, 2.3% or 7% of energy intake. LV volumes were measured by echo. On the standard diet banding increased LV mass by 38%, LV end diastolic volume by 29%, and end diastolic volume by 101% compared to sham (p<0.05). EPA+DHA supplementation increased plasma adiponectin concentration in a dose dependent manner (see Fig.

), and prevented the increases in LV end diastolic volume and end systolic volume (p<0.05). Adiponectin levels were negatively correlated with LV end systolic and diastolic volumes (r=−0.78 and −0.71, respectively; p<0.001). The protective effect of adiponectin has been linked to AMPK activation and/or inhibition of pro-growth Akt, however there were no differences in AMPK or Akt activation by western blot. A parallel series of rats were fed with α-linolenic acid, a ω-3PUFA from flaxseed, over a similar dose range, and showed no increase in adiponectin or prevention of LV pathology. In conclusion, supplementation with EPA+DHA prevented LV remodeling and dysfunction, which was strongly associated with an elevation in plasma adiponectin.
Abstract 5403: Protein Kinase C-Induced Troponin I Phosphorylation Causes Changes in Cardiac Contractile Function but not the Intracellular Calcium Transient
Authors: Kirk Jonathan A , Smith Stephen H , MacGowan Guy A , Shroff Sanjeev G
Published: July 2021

Both intracellular calcium transients ([Ca]
i
) and myofilament properties determine cardiac muscle contractile force. Transgenic mouse models created to perturb specific myofilament proteins often cause a compensatory change in [Ca]
i
, which confounds the assessment of myofilament structure-function relationships. We have created a new transgenic mouse that has all three protein kinase C (PKC) phosphorylation sites on cardiac troponin I (cTnI) mutated to glutamic acid, rendering these sites constitutively pseudo-phosphorylated. Our goal was to determine the effects of this mutation on cardiac muscle contractile function and whether these effects would be concurrent with changes in the [Ca]
i
. Two sets of studies were conducted:

skinned muscle fiber experiments to characterize the steady-state force-pCa relationships at sarcomere lengths of 1.9 and 2.3 μm and

right ventricular papillary muscle experiments to characterize the peak developed force (F
dev
)-muscle length (L) relationships and [Ca]
i
(fura-5F calcium dye, emission: 510 nm, excitation: 340 and 380 nm,
R
= [emission fluorescence
340
]/[emission fluorescence
380
]).

In skinned fibers, there was a significant decrease in maximally activated force (i.e., force at pCa 4.33) in transgenic mice (Wild-Type, WT (n = 7): 64.4± 8.0, Transgenic, TG (n = 6): 42.6±6.8 mN•mm
−2
,
P
= 0.004), without any changes in calcium sensitivity or cooperativity (Hill coefficient). In intact papillary muscles, TG mice showed a decrease in F
dev
and slowed relaxation for all muscle lengths examined (F
dev
@ 100% L
max
, WT (n = 5): 9.3±3.5, TG (n = 6): 4.2±1.6 mN•mm
−2
,
P
= 0.005; dF/dt
min
@ 100% L
max
, WT: −136±32, TG: −74±38 mN•mm
−2
•s
−1
,
P
= 0.002). In contrast, [Ca]
i
was unaltered in TG mice at all muscle lengths examined ([Ca]
i
amplitude as quantified by
R
systole
/
R
diaastole
, WT: 1.62±0.07, TG: 1.48±0.22; [Ca]
i
relaxation rate d
R
/dt
min
, WT: −96±37, TG: −64±30 s
−1
). Thus, PKC-induced TnI phosphorylation affects cardiac muscle contraction (reduced force magnitude and slowed relaxation) via changes in the myofilament properties (activation and/or crossbridge dynamics), and these contractile effects are not related to any changes in the intracellular calcium transient.
Abstract 5404: Perturbation of Tropomyosin Amino Acid Residues Binding to Actin at the “Off” State of Tropomyosin Increase Cardiac Muscle Dynamics
Authors: Muthuchamy Mariappan , Dowdie Rochelle , Wu Xin , Zawieja Scott , Gokulan Kuppan , Tong Carl , Moss Richard
Published: July 2021

Tropomyosin (TM), an essential thin filament protein, binds along F-actin in association with troponin and plays a central role in regulating cardiac muscle dynamics. Previous structural studies have shown that TM molecule consists of 14 negatively charged, alternating α- and β-bands along its length, responsible for binding to actin. The 7 α-bands of TM are implicated in the binding to actin at the “off” state where actomyosin crossbridging is blocked. The 7 β-bands of TM bind to actin at the “on” state that permits actomyosin interaction and results in force production. In this study, we hypothesize that if the α-bands are perturbed by changing the charged residues at that region, it will cause TM molecule “slipping” at the “off” state that will allow TM to be in an extended “on” state leading to enhanced cardiac muscle dynamics. To test this hypothesis we have generated TG mouse lines expressing α-TM with mutations in the α-bands located in the carboxy terminus (α-TM CTM). More specifically, codons encoding negatively charged amino acids (aspartate or glutamate) at positions 212, 219, 223, 255 and 259 were changed to lysine by site-directed mutagenesis. Molecular analyses revealed one of the TG lines α-TM CTM-6 expressed 100% of mutant protein. Echocardiogram data analyses showed that α-TM CTM-6 hearts exhibited significant decrease in heart rate (10%; p<0.05, n=6)) in the absence or presence of dobutamine. Furthermore, the percentage fractional shortening and ejection fraction were significantly increased (13% and 15%, respectively, p<0.05, n=6) in TG hearts when compared to non-transgenic (NTG) controls. To investigate the mechanisms for the increase in cardiac muscle dynamics in the TG hearts, we measured force and calcium levels in the papillary muscle fiber. Force- [Ca2+]i data analyses showed that the α-TM CTM TG hearts produced more force per given [Ca2+]i when compared to NTG hearts, indicating that α-TM CTM myofilaments exhibit an increase in Ca2+ sensitivity. Protein modeling analyses show surface charges of α-TM CTM molecule is altered. We propose that the changes in charged residues in the α-bands located in the C-terminus of TM molecule perturb the “off” state, which augment the crossbridge kinetics and lead to enhanced cardiac muscle performance.
Abstract 5425: Nuclear Shuttling of Sirt1 Is Associated with Caloric Restriction-Induced Cardioprotection
Authors: Shinmura Ken , Tamaki Kayoko , Bolli Roberto
Published: July 2021

Ischemic tolerance decreases with ageing and the cardioprotective effect of ischemic preconditioning (PC) is impaired in middle-aged animals. We have demonstrated that short-term caloric restriction (CR) improves myocardial ischemic tolerance via the activation of adiponectin-AMPK-mediated signaling. However, it is unknown whether prolonged CR confers cardioprotection in a similar manner. Furthermore, little is known regarding the myocardial expression of sirt1 (which reportedly mediates various aspects of the CR response) with ageing and prolonged CR. Thus, 6-month-old Fischer344 rats were randomly divided into ad libitum (AL) and CR groups. Six months later, isolated perfused hearts were subjected to 25 min of global ischemia followed by 30 min of reperfusion with or without ischemic PC. CR improved the recovery of LV developed pressure (A) and restored the cardioprotective effect of ischemic PC. Serum adiponectin levels increased but myocardial levels of total and phosphorylated AMPK did not change with prolonged CR. Total levels of sirt1 did not change with ageing and CR; however, in the nuclear fraction, CR significantly increased sirt1 (B) and decreased acetyl-histone H3. Eight rats from each group were given L-NAME in the drinking water for 4 weeks before sacrifice. In these hearts, chronic inhibition of nitric oxide (NO) synthase prevented the nuclear shuttling of sirt1 by CR (B) and abrogated CR-induced cardioprotection (A). These results demonstrate that

prolonged CR improves myocardial ischemic tolerance and restores ischemic PC in middle-aged rats, and that

CR-induced cardioprotection is associated with NO-dependent nuclear shuttling of sirt1.
Abstract 5463: Dual Channel Hybrid Fluorescence Molecular Tomography/X-ray Computed Tomography (FMT-CT) of Inflammation in Murine Atherosclerotic Plaques
Authors: Nahrendorf Matthias , Waterman Peter , Weissleder Ralph
Published: July 2021

Monocyte/macrophages play a key role in the development and progression of atherosclerotic lesions. Here we present a novel hybrid in vivo imaging approach that simultaneously reports on lesion anatomy, phagocytic activity by uptake of fluorescent nanoparticles and extracellular matrix remodeling with a protease-activatable agent, detectable with hybrid FMT-CT imaging. We co-injected 5 aged apoE deficient and 5 wild type mice with 15mg/kg of macrophage-avid nanoparticle (CLIO-680, emission 700nm) and 2nmol of a cathepsin-activatable protease reporter (Prosense-750, emission 780nm). Mice were imaged using a free space dual channel FMT system inside a cartridge that is optically translucent and has multimodal fiducial markers for image fusion incorporated in its frame. While the immobilized mice were anesthetized with isoflurane, the holding device was transferred for ECG-gated high resolution CT (isotropic resolution 50um). During CT acquisition, iodine contrast was delivered at 65ul/min via tail vein. In vivo, we found strong fluorescent signal for uptake of nanoparticles as well as protease activity (p<0.05 WT vs apoE−/− mice), which was mapped to the proximal aorta on CT. Contrast enhanced CT visualized murine aortic plaques. Ex vivo fluorescence reflectance imaging and fluorescence microscopy corroborated in vivo findings and identified macrophages as target cells. FMT-CT imaging of inflammatory atherosclerosis provides quantifiable 3-dimensional maps of macrophage activity and visualizes murine aortic plaques, providing unprecedented insight into disease progression non-invasively.
Abstract 5492: Tetrahydrobiopterin (BH4) Improves Endothelial Cell Survival After Vascular Injury
Authors: Rinze Ruth , Ali Ziad A , Douglas Gillian , Alp Nicholas J , Channon Keith M
Published: July 2021

Endothelial cell loss, survival and regeneration are important aspects of the response to vascular injury leading to neointimal hyperplasia and accelerated atherosclerosis. Nitric oxide (NO), produced by endothelial nitric oxide synthase (eNOS), is a key regulator of endothelial cell biology and has been shown to prevent endothelial cell apoptosis. The cofactor tetrahydrobiopterin (BH4) is essential for eNOS catalytic activity but its impact on endothelial cell survival and regeneration remains unclear. We investigated the effect of BH4 on endothelial cell survival and vascular remodelling using ApoE-KO mice with transgenic endothelial-targeted overexpression of GTP cyclohydrolase 1 (GCH), the rate limiting enzyme of BH4 synthesis, and with endothelial specific transgenic expression of the LacZ reporter gene. Using venous bypass grafts as an in vivo model of acute vascular injury, we observed that endothelial-specific augmentation of BH4 in GCH/ApoE-KO mice improved survival of vein graft-derived endothelial cells and reduced neointimal hyperplasia. To address the hypothesis that augmentation of BH4 increases the capacity of endothelial cells from GCH/ApoE-KO mice to survive vascular injury, we cultured primary lung endothelial cells from mice expressing the GCH transgene and wild type littermates. Endothelial cells, isolated by immunomagnetic beads, were positive for CD31, CD102 and Tie2. Protein levels of eNOS were not different between wild type and GCH mice. BH4 levels were selectively increased in pulmonary endothelial cells from GCH mice, > 10-fold, compared with a 3-fold increase in total lung tissue BH4. There was no difference in total lung endothelial cell content or amount of isolated cells between ApoE-KO and GCH/ApoE-KO mice, determined by Tie2-driven β-galactosidase activity. However, after 3 days of culture both total endothelial cell number and number of endothelial cell colonies in GCH/ApoE-KO were significantly increased (236% ± 47 p=0.028 and 195% ± 28 p=0.014 respectively, n=5) whereas mean colony size remained unchanged. These observations indicate an important role for BH4 in endothelial cell survival and endothelial regeneration, and identify BH4 as a potential therapeutic target in vascular injury states.
Abstract 5497: Chronic Stenosis of the Proximal Left Anterior Descending Coronary Artery in Juvenile Rats Results in a Critical Impairment in Coronary Flow Reserve and Leads to the Development of Hibernating Myocardium without Necrosis
Authors: Hu Qingsong , Cimato Thomas R , Fallavollita James A , Canty John M
Published: July 2021

Background:
Previous studies in adult rats have shown that a chronic coronary artery stenosis can produce variable degrees of heart failure and global LV dysfunction with concomitant fibrosis and necrosis. In contrast, placement of a fixed LAD stenosis in juvenile swine leads to the gradual development of hibernating myocardium with regional dysfunction in the absence of infarction. We hypothesized that a similar approach could be used to produce hibernating myocardium in growing rats.

Methods:
Sprague-Dawley rat pups (3 wk old, 40±2g, n=24) were instrumented with a 200μm stenosis using an 8 – 0 suture around the proximal LAD and compared to sham controls (n=7). At 12-wks post-instrumentation (399±6g), ejection fraction (EF) and regional wall thickening (%WT) were determined by echocardiography and myocardial perfusion was measured using fluorescent microspheres (n=8). Histology was used to assess necrosis, fibrosis and regional myocyte loss.

Results:
Mortality was low (16%) and survivors (n=20) had no gross evidence of infarction. LAD end-diastolic wall thickness was normal (1.2 ± 0.04 vs. 1.2 ± 0.04 mm in controls, p=ns) and EF was preserved (65 ± 2% vs.70±1% in controls, p=0.07). After 12 weeks, LAD %WT was significantly reduced (49 ± 5% vs. 74 ± 5% in remote, p<0.01). In LAD subendocardium, vasodilated flow was decreased (3.1 ± 0.7 vs.7.1±1.2 ml/min/g in remote, p<0.01) with a critical impairment in coronary flow reserve (adenosine/rest 1.2 ± 0.3 vs.1.8 ± 0.2 in remote, p<0.05). Although fibrosis and necrosis were absent, regional myocyte nuclear density in LAD subendocardium decreased (489 ± 27 vs. 628 ± 24 nuclei per mm
2
in remote, p<0.01) and relative reductions were closely correlated with LAD flow reserve (r =0.76, p<0.05) and LAD %WT (r =0.54, P<0.05).

Conclusion:
Like swine, a chronic LAD stenosis in growing rats leads to a critical impairment in coronary flow reserve with reduced regional myocardial perfusion, wall thickening and regional myocyte loss without infarction. Our findings establish a model of hibernating myocardium in rodents, facilitating high-throughput studies to identify novel mechanisms and therapies for chronic ischemic LV dysfunction.
Abstract 5502: Adiponectin Mediates the Effects of Atherogenic Risk Profile on the Coronary Microcirculation in Patients with Idiopathic Lv Systolic Dysfunction
Authors: Giannessi Daniela , Caselli Chiara , Del Ry Silvia , Maltinti Maristella , Cabiati Manuela , Abraham Nader , L’Abbate Antonio , Neglia Danilo
Published: July 2021

Purpose.
Adiponectin (ADN), a biologically active protein produced by the adipose tissue, has protective vascular effects. Accordingly, ADN plasma levels are reduced in patients with coronary artery disease (CAD) while in heart failure ADN tends to increase. We hypothesized that ADN plasma levels could mediate the effects of atherogenic risk profile on the coronary microcirculation of patients with early LV systolic dysfunction (ILVDys) not secondary to established CAD.

Methods.
Plasma ADN was measured in 55 patients (age 59±1 yrs, 36 males, BMI 26.9±0.49 Kg/m
2
, mean±sem) with angiographically normal coronary arteries, LV systolic dysfunction (LVEF 39.8±1.3 % range 22–54 %) but without overt heart failure (NYHA class I–II) and in 40 age- and BMI-matched healthy controls by using a specific Elisa (Linco Res). BMI, cholesterol and glucose profiles were assessed in all. In a subset of 25 patients coronary microvascular function was studied by PET and
13
N-Ammonia as a flow tracer. Myocardial blood flow (MBF) was measured at rest and during i.v. dipyridamole (Dip) (0.56 mg/Kg in 4 min).

Results.
ADN was 6.6±0.34 μg/ml in controls and 10.9±0.85 in ILVDys patients (p<0.001). In patients ADN levels were inversely related with BMI (p=0.009) and directly related with age (p=0.007), HDL Cholesterol (p=0.003) and MBF Dip (0.020). Patients showing more severe coronary microvascular dysfunction (MBF Dip<1.42 ml/min/g, median value in patients) had significantly depressed ADN (9.7±2.3 vs 13.7±1.6, p=0.021) as compared with the remaining patients.

Conclusions.
This is the first study which associates adiponectin plasma levels with atherogenic risk profile and coronary microvascular function in patients with idiopathic LV dysfunction. These results suggest that adiponectin signal is strongly involved in mediating coronary vascular function independently of the presence of overt CAD or heart failure.
Abstract 5507: Toll Like Receptor 4 Activation Elicits Pro-atherogenic Gene Activation In Monocytes In Humans
Authors: Sivapalaratnam Suthesh , Farrugia Rosienne , Nieuwdorp Max , Gusnanto A , Watkins Nick A , Zwaginga Jaap-Jan , Ouwehand Willem H , Trip Mieke D , Stroes Erik S , Kastelein John J
Published: July 2021

Introduction:
Inflammatory activation of both circulating blood cells as well as vessel wall cells is a hallmark of atherogenesis. Agonists of the Toll-like receptor 4 pathway, present on white blood cells as well as endothelial cells, have been associated with a pro-atherogenic state. Recently, standardized inflammatory challenge models using lipopolysaccharide (LPS) have been suggested to mimick these atherogenic changes. However, similarity between circulating pathways and ’vessel wall’ pathways need further validation. Therefore, we evaluated the effects of in vivo LPS challenge on circulating monocytes in humans.

Methods:
A bolus of Escherichia coli endotoxin (LPS 1 ng/kg bodyweight) or NaCl was infused intravenously in healthy male volunteers (n=13). Blood was drawn at 0, 1 and 4 hours after the challenge. The monocytes (CD14+ cells) were isolated using positive MACS selection. Subsequently, mRNA sample extraction using RnaseBee was performed. cDNA was prepared, amplified, labeled and then hybridized onto spotted oligonucleotide microarrays before scanning. Data were analyzed using R-project version 2.2.0. Validation Taqman took place.

Results:
Following LPS challenge, CD14+ count dropped by 48% in the first hour due to margination of monocytes, followed by normalization at 4 hours. Purity of CD14+ fraction approximated 90%. LPS was associated with upregulation of a series of pro-atherogenic genes (BID, DIPA, FRA-1, HSP27, HSP70, ILRN, MIP-1a, MIP1b, S100A9, SLA1, TIMPS, TLR2), immune system related genes (CLP1, DF, CD45-AP, HLA-DPB1, BATF, C3AR1, CD14) as well as a series of unrelated genes. No genes were differentially expressed during saline control experiments. RT-PCR confirmed upregulation of CD14, SLA1, BATF, C3AR1, MIP-B, TLR-2, VCAN and ILRN.

Conclusion:
TLR4 activation following LPS challenge is associated with potent activation of monocytic pathways involved in chemotaxis and immune activation. These activation patterns bear great resemblance to those reported in atherogenic vessel wall. It is tempting to speculate that circulating cells (’vulnerable blood’) can be used as a surrogate to detect high-risk vessel wall lesions (vulnerable patient).
Abstract 5530: Predominant Types of Dyslipidemia in U.S. Adults with Coronary Heart Disease and Diabetes
Authors: Wong Nathan D , Ghandehari Heli , Le Hoangvy , Ambegaonkar Baishali M , Sazonov Vasilisa
Published: July 2021

Background:
The prevalence of isolated (one lipid disorder) and mixed (≥2 lipid disorders) dyslipidemia has not been well-chararacterized, particularly among patients with coronary heart disease (CHD) and type 2 diabetes mellitus (DM). We examined the association between types of dyslipidemia and CHD or DM among a representative sample of US adults.

Methods:
We studied 2,827 adults with complete lipid data for LDL-C, HDL-C and triglycerides (TG) representing 126 million US adults in the National Health and Nutrition Examination Survey (NHANES) 2003–2004. We determined the prevalence of elevated LDL-C (as per NCEP guidelines), low HDL-C (<40 mg/dL for men and <50 mg/dL for women) and/or elevated TG (≥200 mg/dL) among those with CHD (n=134) or DM (n=277). Multivariate logistic regression examined the association between CHD or DM and types of dyslipidemia while controlling for clinical and demographic characteristics.

Results:
Overall, 74% with CHD and 80% of those with DM had ≥1 lipid disorder. Among CHD patients, 60%, 27% and 27% had elevated LDL-C, low HDL-C and elevated TG respectively, while 20% had 2 lipid disorders and 10% had all 3. Among DM patients, 65%, 40% and 22% had elevated LDL-C, low HDL-C, and elevated TG respectively, while 29% had 2 lipid disorders and 10% had all 3. Compared to those with no lipid disorder, the odds of CHD were 4–6 times greater with elevated LDL-C combined with elevated TG regardless of HDL-C. In contrast, the odds of DM were the greatest in those with elevated LDL-C and low HDL-C regardless of TG. Other types of dyslipidemia were less strongly or not associated with CHD or DM (Table

).

Conclusions:
In this representative sample of US adults, CHD was most closely associated with elevated LDL-C combined with elevated TG regardless of HDL-C levels, while DM was most closely associated with elevated LDL-C and low HDL-C regardless of TG levels. These differences should be considered when choosing therapies for dyslipidemia in patients with CHD and DM.

Multivariable Adjusted Odds of Coronary Heart Disease (CHD) or Diabetes (DM) by Lipid Disorder
Abstract 5543: The P2Y
2
Nucleotide Receptor Contributes To Intimal Lesion Growth And Regulates Lymphotoxin-α Secretion
Authors: Weisman Gary , Yu Ningpu , Agca Cansu , Shivaji Rikka , Wan Ying , Yuksel Agca , Seye Cheikh
Published: July 2021

Inflammatory processes play a crucial role in atherosclerotic lesion growth. A number of pro-inflammatory molecules have been implicated in the pathogenesis of atherosclerosis, including lymphotoxin-α (LTA). Our research has shown that activation of a G protein-coupled P2Y
2
nucleotide receptor (P2Y
2
R) expressed in vascular cells mediates inflammatory responses. To examine the role of the P2Y
2
R in lesion growth, we developed P2Y
2
R over-expressing transgenic rats. Collar-induced injury to the carotid artery of P2Y
2
R transgenic rats caused a dramatic increase in intimal lesion growth and significant macrophage accumulation, which nearly blocked the arterial lumen. Immunohistochemical staining showed that LTA and galectin-2 (gal-2) were abundantly expressed in smooth muscle cells (SMC) and macrophages in carotid lesions of P2Y
2
R transgenic rats. We also identified galectin-2 as a P2Y
2
R binding partner using the yeast two-hybrid system and a co-immunoprecipitation assay. P2Y
2
R agonist, UTP, stimulated gal-2 mRNA expression in rat carotid SMC. Transient transfection of SMC with a genomic fragment including the rat galectin (LGALS2) promoter incorporated into a luciferase (pGL-3) reporter vector showed that UTP markedly increased LGALS2 promoter activity in a dose-dependent manner. Moreover, UTP induced LTA secretion in cultured aortic SMC from wild type, but not P2Y
2
R
−/−
mice. Adenoviral expression of the full length P2Y
2
R in SMC from P2Y
2
R
−/−
mice fully restored UTP-induced LTA secretion. However, expression of a mutant P2Y
2
R that does not bind filamin A, an actin-binding protein that interacts with the P2Y
2
R, only partially restored UTP-induced LTA secretion in P2Y
2
R
−/−
SMC. Gal-2 siRNA partially inhibited LTA release into medium of cultured SMC expressing the P2Y
2
R. In contrast, gal-2 siRNA abolished UTP-induced LTA secretion in SMC isolated from P2Y
2
R
−/−
mice expressing the filamin A binding mutant P2Y
2
R. These results indicate that P2Y
2
Rs regulate gal-2-dependent LTA secretion in SMC via a filamin A-dependent mechanism that likely contributes to vascular inflammation.
Abstract 549: ST-Segment Analysis Using Wireless Technology in Acute Myocardial Infarction (STAT-MI) Trial: Early vs. Late Experience
Authors: Maher James M , Dhruva Vivek N , Solanki Pallavi , Zakir Ramzan , Kaluski Edo , Klapholz Marc
Published: July 2021

Background:
We previously reported our early (initial 6 month) experience using a fully automated wireless network to shorten door to intervention (D2I) times. Later experience allowed for further refinement of this network. Early D2I times are expected to result in smaller infarcts and decreased lengths of stay.

Methods:
A fully automated wireless network that facilitates simultaneous 12-lead ECG transmission from emergency medical services (EMS) personnel in the field to the Emergency Department (ED) and offsite cardiologists via smart phones. This allows direct communication between offsite cardiologist and EMS and facilitates patient triage directly to the cath lab. Demographic, laboratory and time interval data were prospectively collected over a 23-month period and compared to calendar year 2005 data. Early experience (first 6 months) was compared to later experience.

Results:
From June 2006 through April 2008, 242 ECGs with suspected ST segment elevation myocardial infarction (STEMI) were transmitted via the STAT-MI network. Compared with 2005 data, door to cardiology notification time was reduced from 61.4 minutes (min) to −15.8 min (p < 0.001), door to arterial access time decreased from 108.1 to 42.1 min (p < 0.0001), door to intervention (D2I) time decreased from 145.7 to 68.8 min (p = 0.00001), hospital length of stay decreased from 5.4 ± 4.5 days to 4.1 ± 5.0 days (p < 0.29), and troponin elevation decreased from 106.4 ng/ml to 73.9 ng/ml (p < 0.19). The magnitude of timesavings was similar regardless of time of presentation, though D2I times were longer during “off” hours (after 5pm and weekends) as compared to “on” hours (85.7 min vs. 51.8 min P=0.001). Protocol refinements introduced over the first 6 months further shortened D2I times; 87 min vs 65 min in the first 6 months and in the subsequent 17 months respectively (p = 0.09).

Conclusions:
A fully automated wireless network that transmits ECGs simultaneously to the ED and offsite cardiologists for the early evaluation and triage of patients with STEMI markedly and consistently shortened D2I times. A strong positive trend in outcome measures was also observed with reduced length of stay and smaller infarct size. There was a 6 month learning curve to fully realize the benefits of this new automated system.
Abstract 571: Prognostic Value of Albuminuria on One Month Mortality in Acute Myocardial Infarction
Authors: Schiele Francois , Meneveau Nicolas , Chopard Romain , Descotes-Genon Vincent , Oettinger Joanna , Seronde Marie-France , Ecarnot Fiona , Bassand Jean-Pierre
Published: July 2021

Background: Albuminuria is associated with hypertension, renal and endothelial dysfunction, inflammation, insulin resistance and atherogenic lipid profile. An increase in albuminuria occurs in the early days after acute myocardial infarction. The aim of this study was to assess the relation between albuminuria and 30 day mortality, as well as its incremental predictive value on top of established prognostic parameters.

Methods: Demographic, clinical and biological characteristics at admission, in-hospital treatments and one month survival were recorded in 1188 consecutive patients admitted for acute myocardial infarction. Albuminuria was assessed from an 8-hour, overnight urine collection at day 3 using immunonephelemetry. The population was categorized according to albuminuria <20, 20 to 200 and >200 μg/min.

Results: Fifty one percent (625/1188) of patients had an albuminuria level below 20 μg/min, 40% (296) between 20 and 200 μg/min and 9% (109) above 200 μg/min. High levels of albuminuria were associated with older age, history of hypertension, previous surgical coronary revascularization, stroke or peripheral vessel disease. Albuminuria was also correlated with troponin release, BNP and high sensitive CRP. At one month, there was a significantly higher mortality rate in groups with higher albuminuria (31/635(5%), 64/477(13%) and 22/109(20%) for albuminuria <20, 20–200 and >200 μg/min respectively). Multivariable analysis showed that albuminuria was an independent predictor of mortality. After adjustment on the GRACE risk score and the use of guidelines-recommended treatments, patients with albuminuria >20 μl/min had a 4-fold higher 30 day mortality, and those >200 μl/min had a 5 fold higher 30 day mortality, as compared with patients with albuminuria <20 μl/min (OR 4 [1.3–12.5] and 5.9 [1.64–20] for albuminuria >20 μl/min and >200 μl/min respectively).

Conclusions: Albuminuria level is an independent and powerful predictor of mortality after acute myocardial infarction.
Abstract 630: Continuous Reduction of N-Terminal Pro-Brain Natriuretic Peptide Levels after Successful Catheter Ablation in Patients with Paroxysmal or Short Persistent Atrial Fibrillation
Authors: Hoenig Simon , Hofmann Robert , Steinwender Clemens , Kypta Alexander , Leisch Franz
Published: July 2021

It has been reported previously that elevated N-terminal pro-brain natriuretic peptide levels (BNP) decrease in patients with atrial fibrillation (AF) within one month of pulmonary vein isolation (PVI). The purpose of the study was to examine the development of BNP levels after successful PVI. In 71 patients (mean age of 62 ± 8 years) undergoing successful PVI for drug-resistant highly symptomatic paroxysmal or shortly persistent AF, BNP levels were analysed the day before, 30 days after, three months after and one year after the procedure, respectively. Based on a personal log of duration and frequency of symptoms and repetitive 24h-ECG recordings, patients were divided into two groups: 36 patients had clinical success, and 16 patients had clinical failure. Clinical demographic and procedural data were similar in both groups. Of note, all patients had lone AF without any clinical signs of congestive heart failure. Baseline BNP levels were similar in both groups (387± 550 pg/ml vs. 492 ± 513 pg/ml, p=0.6). After 30 days, patients who had a clinical successful procedure showed a significant decrease of BNP levels compared to those patients with clinical failure (315 ± 430 pg/ml vs. 754 ± 888 pg/ml, p=0.02). After three months, a further reduction of BNP levels could be observed in clinical successful treated patients compared to patients with clinical failure, in whom no significant change compared to baseline could be detected (214 ± 213 pg/ml vs. 673 ± 907 pg/ml, p=0.01). After one year of successful PVI a repeated reduction of BNP in patients with clinical success could be observed (173 ± 198 pg/ml vs. 448 ± 628 pg/ml, p=ns.), but due to the small sample size the difference did not reach statistic significance. Similar to previous observations, BNP levels after successful PVI decreased only in patients with clinical success during follow-up. However, our study revealed a long-term effect showing a further decrease after one year whereas BNP levels showed even a further increase during the first three months in patients without clinical success. This observation points to an underestimated impact of AF concerning congestive heart failure even in patients without regarding symptoms.
Abstract 649: Increased Left Ventricular Filling Pressure is Associated with Left Atrial Thrombus in Patients with Atrial Fibrillation.
Authors: Iwakura Katsuomi , Ito Hiroshi , Okamura Atsunori , Koyama Yasushi , Date Motoo , Higuchi Yoshiharu , Inoue Koichi , Kimura Ryusuke , Nagai Hiroyuki , Toyoshima Yuko , Imai Michio , Ozawa Makito , Ito Norihisa , Okazaki Yukinori , Shibuya Masahiko , Suenaga Hidetaka , Kubota Asuka , Fujii Kenshi
Published: July 2021

Patients with atrial fibrillation (AF) are frequently associated with reduced left ventricular (LV) diastolic dysfunction. It is still unclear whether reduced diastolic function is associated with the risk of left atrial (LA) thrombus in AF. The ratio of transmitral E velocity to mitral annular velocity (e′) is an echocardiographic estimate of diastolic LV filling pressure even under AF rhythm. We investigated whether reduced LV diastolic function is associated with the risk of LA thrombus in AF patients, using E/e′ ratio as an index. We enrolled consecutive 405 patients with non-valvular, paroxysmal or chronic AF, who underwent both transthoracic- (TTE) and transesophagial echocardiography (TEE) examination within a month. We measured LA and LV dimensions, LV ejection fraction (%EF), wall thickness, E and e′ velocities on TTE, and determined E/e′ ratio. LA appendage thrombus was found in 33 patients (8.1%). Patients with LA thrombus showed lower e′ velocity (5.3±1.8 vs. 7.0±2.2 cm/s, p<.0001) and higher E/e′ ratio (17.2±9.2 vs. 11.5±5.9, p<.0001) than those without it. Using 12.4 as an optimal cutoff point, E/e′ predicted LA thrombus with 70% sensitivity and 70% specificity (AUC=0.72). Odds ratio for LA thrombus in patients in the highest quartile of E/e′ was 6.38 (3.06–13.9). Multivariate logistic regression analysis indicated that the highest quartiles of E/e′ ratio was an independent predictor of LA thrombus among echocardiographic parameters, along with LA dimension and %EF, whereas e′ was not. LA appendage flow velocity was significantly correlated with E/e′ ratio (p<.0001), implying that increased diastolic filling pressure could be associated with impaired blood flow within LA. Increased LV filling pressure increased the risk of LA thrombus in patients with AF, partially through impaired LA hemodynamics. E/e′ ratio on TTE could be useful for detecting high-risk patients for LA thrombus.
Abstract 684: Intensive Statin Therapy Decreases Lipid-Rich Coronary Plaques as Detected by 64-Slice Computed Tomographic Angiography
Authors: Kitagawa Toshiro , Yamamoto Hideya , Ohhashi Norihiko , Kunita Eiji , Utsunomiya Hiroto , Ishida Takafumi , Tadehara Futoshi , Teragawa Hiroki , Nakano Yukiko , Shokawa Tomoki , Kihara Yasuki
Published: July 2021

Computed tomography (CT) densities within coronary plaques measured by multislice CT have been shown to reflect plaque components. We evaluated an effect of statin therapies on characteristics of non-calcified coronary atherosclerotic lesions (NCALs) defined by CT density. We studied 92 consecutive stable patients (67 men, age 67 ± 9 years) with at least one NCAL detected by 64-slice CT angiography (CTA). We excluded patients with previous coronary revascularization procedures. Each NCAL (size >1-mm
2
, density <120HU) was evaluated with the minimum CT density (ROI = 1-mm
2
). NCALs with <40HU were considered as lipid-rich based on our previous report. We examined drug uses (intensive statins [IS; atorvastatin or rosuvastatin], non-intensive statins [NS; pravastatin or simvastatin], ACE inhibitors or ARB, and aspirin) continuing for >6-months before CTA in each patient. There were no significant differences in the patient’s characteristics and drug uses except for statin among the three groups classified by statin use (IS: n = 21, NS: n = 23, and no statin: n = 48). Serum LDL-cholesterol level (90 ± 18 vs. 115 ± 30 vs. 122 ± 34 mg/dl, p = 0.0005) and LDL/HDL-cholesterol ratio (1.6 ± 0.5 vs. 2.3 ± 0.7 vs. 2.5 ± 1.1, p = 0.002) were lower in the IS group than the others. A total of 191 NCALs (lipid-rich; 91 lesions) were detected by CTA. The number of all NCALs per patient was similar among the three groups (2.0 ± 0.9 vs. 2.1 ± 1.2 vs. 2.1 ± 1.0), while that of lipid-rich NCALs per patient was lower in the IS group than the others (0.5 ± 0.6 vs. 1.2 ± 0.9 vs. 1.1 ± 0.9, p = 0.01). On multivariate analysis regarding age, gender, coronary risk factors, and drug uses, the IS use was only significant predictor for decreasing lipid-rich NCALs (coefficient value −0.46, 95% CI −0.78– −0.14, p = 0.006). Otherwise, among the three groups classified by the number of lipid-rich NCALs per patient (absence: n = 26, one: n = 46, and ≥2: n = 20), the difference of LDL/HDL-cholesterol ratio was most significant (1.9 ± 0.6 vs. 2.1 ± 0.9 vs. 2.9 ± 1.1, p = 0.0004). Our CT findings support the concept that intensive statin therapy stabilizes lipid-rich coronary plaques. LDL/HDL-cholesterol ratio is most strongly related to lipid-rich NCALs on CTA.