bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 20258: Stenosis Severity and Kidney Function in Atherosclerotic Renal Artery Stenosis
Authors: Yu Mark Shipeng , Matsumoto Alan H , Pencina Karol , Tuttle Katherine , He Wencan , Evans Kaleigh , Ren Kaili , Folt David A , Brewster Pamela S , Murphy Timothy P , Cutlip Donald E , Dworkin Lance D , Jaff Michael R , Steffes Michael , Shapiro Joseph I , Henrich William , Cooper Christopher J
Published: July 2021

Introduction:
Ischemic nephropathy due to atherosclerotic renal artery stenosis (ARAS) is associated with poor event free survival. However, previous studies suggest that stenosis severity has a poor relation to kidney function. We sought to test the interactions of stenosis severity, and revascularization, on kidney function in people with ARAS.

Hypothesis:
Stenosis severity is associated with poor renal function in people with ARAS.

Methods:
The Cardiovascular Outcomes in Renal Atherosclerotic Lesions (CORAL) clinical trial is a prospective trial of individuals with atherosclerotic renal-artery stenosis. Patients were followed to a maximum of 8 years. Angiographic images were measured at a single core lab (University of Virginia) using quantitative computer-assisted angiography. Estimated glomerular filtration rate (eGFR) was measured using creatinine and cystatin-C, performed at a single core lab (University of Minnesota), and calculated using the CKD-EPI Creatinine-Cystatin C formula. The analyses are controlled by age and gender.

Results:
At baseline CKD-EPI eGFR was strongly and negatively correlated with percent stenosis (-0.2472, p<0.0001) and positively correlated with minimal luminal diameter (0.2974, p<0.0001). Interestingly, peak systolic pressure gradient and mean pressure gradients were not (p=ns for both). At three years follow-up baseline percent stenosis remained significant by univariate analysis (0.1380, p=0.01), however, it was not significant by multivariate analysis.

Conclusions:
Stenosis severity is strongly related to kidney function at the time of presentation in patients with atherosclerotic renal artery stenosis. However, by three years follow-up, this relationship appears to be lost.
Abstract 20260: The Effect of Lifestyle Recommendations on Blood Pressure and Blood Pressure Control in Patients With Stage I Hypertension: The Prever Treatment Trial
Authors: Fuchs Flávio D ,   PREVER Study investigators - http://www.trialsjournal.com/content/12/1/53
Published: July 2021

Introduction:
Lifestyle recommendations are recommended for patients with Stage I hypertension before starting blood pressure-lowering drugs in patients free of cardiovascular disease. The proportion of patients that have blood pressure (BP) controlled with these recommendations was scarcely reported in a clinical context.

Hypothesis:
To investigate the rate of response to a short-term lifestyle intervention (LsI) in the first phase of a randomized clinical trial.

Methods:
PREVER prevention is a double blind, multicenter, randomized clinical trial of effectiveness of drug treatment to control hypertension and target organ damage among individuals with hypertension. It was conducted in 22 centers distributed in 10 Brazilian states. Participants were enrolled in the study if they had hypertension (≥140 of systolic blood pressure or ≥90 mmHg of diastolic blood pressure), confirmed in two visits in the clinics of the study, or if they had normal BP but were using BP-lowering agents. BP measurements were carried out using an oscillometric monitor, and anthropometric measurements were taken in duplicate. All participants were submitted to a lifestyle intervention (LsI) phase, which included detailed recommendations to lose weight, to reduce salt, to adopt a DASH-type diet and to practice physical activities. Blood pressure and control of hypertension were verified after three months. In this analysis, we present the results of blood pressure control and variation in the subsample of participants who had BP higher or equal to 140/90 mmHg.

Results:
4 867 volunteers were screened and 1 835 evaluated for enrollment. From these, 685 (37%) had BP within stage I hypertension. After three months of intensive LsI, 420 (61.3%) remained with uncontrolled BP, 249 (36.4%) had BP in the 120-139/80-89 mmHg range, and 16 (2.3%) had normal BP. Systolic and diastolic BP reduced from 143.8 ±7.1 to 138.7 ±12.2 mmHg and 90.4 ±5.9 to 87.7 ±8.7, respectively.

Conclusion:
Approximately 1/3 of patients with Stage I hypertension have blood pressure controlled after three months of lifestyle recommendations to lose weight, reduce salt intake, adopt a DASH diet and practice physical activities.
Abstract 20383: The Impact of Flow Measurement After Mitral Paravalvular Leak Closure and Survival
Authors: Sarraf Mohammad , Pollak Peter M , Malouf Joseph F , Nkomo Vuisile T , Cabalka Allison K , Nishimura Rick A , Rihal Charanjit S
Published: July 2021

Introduction:
Mitral paravalvular leak (PVL) occurs in 7-17% of patients after mitral valve surgery. The percutaneous closure of these defects has become a novel treatment to prevent repeat operations.

Hypothesis:
We hypothesize flow dynamics correlate with clinical outcomes of patients undergoing percutaneous mitral PVL closure.

Methods:
We retrospectively studied 148 patients who underwent percutaneous PVL closure between 2004 and 2014 at Mayo Clinic. We measured the continuous wave (CW) Doppler time velocity integral (TVI), E velocity (as a surrogate for V wave) across the mitral valve and left ventricular ejection fraction (LVEF) by transthoracic echocardiogram within 7 days before and after PVL closure. We identified patients as non-responders if there was moderate to severe residual mitral regurgitation. t-Test was used for continuous variables and Fisher exact test was used mortality.

Results:
Overall, the mean CW TVI was markedly reduced by PVL closure (93±14 vs. 58±5cm, p<0.02). The E velocity also decreased after closure (3.1±0.4 vs. 1.9±0.1m/sec, p<0.04). LVEF, however, was reduced after PVL closure (62%±2 vs. 53%±1.5, p<0.02). Among non-responders (34/148 patients), there was no significant difference between the CW and E velocity before and after the procedure (CW TVI: 96±16 vs. 83+13cm, E velocity: 2.5±0.5 vs. 2.3±0.3m/sec, p=NS). The estimated 5-year mortality of patients with no or mild residual mitral regurgitation was markedly lower compared to non-responders, 43% vs 71%, p<0.05.

Conclusions:
The flow dynamics across the mitral valve immediately after PVL closure may correlate with long term clinical outcomes. Real time assessment of flow by transesophageal echocardiogram can be used to guide the extent of PVL closure required to change the long term clinical outcomes. Further validation and prospective studies are required.
Abstract 20421: Polarizing State Induced by Adenosine, Lidocaine and Magnesium Administration After Prolonged Circulatory Arrest Improves Cardioprotection and Neuroprotection in a Rat Model of Cardiac Arrest With Extracorporeal Life Support
Authors: Rungatscher Alessio , Dobson Geoffrey P , Linardi Daniele , Milani Elisabetta , Tessari Maddalena , Fabene Paolo F , Tong Giang , Schmitt Katharina , Faggian Giuseppe
Published: July 2021

BACKGROUND:
Polarized arrest, a new concept of myocardial protection, has been recently demonstrated to improve cardiac function after cardioplegic arrest during cardiac surgery. The present study investigated whether polarizing state after prolonged cardiac arrest would provide cardioprotective and neuroprotective effects after extracorporeal life support (ECLS).

METHODS AND RESULTS:
Ventricular fibrillation (VF) was induced in male Wistar rats. After 8 min of untreated VF, veno-arterial ECLS was instituted for 60 min inducing mild therapeutic hypothermia (32°C). At the beginning of ECLS animals were randomized to receive a single iv bolus of 4.5 mL/kg of polarizing solution with adenosine (47 μM), lidocaine (92 μM) and MgSO4 (1 mM) or same volume of saline as control.

Restoration of spontaneous circulation was higher in rats that received polarizing solution (p = 0.03). After 24 h survival and neurologic deficit scores were improved and histological damage scores and brain TNF-α were attenuated compared to control (all p<0.05).

Polarizing solution administration led to better recovery of left ventricle end-systolic pressure-volume relationship (Ees), preload recruitable stroke work (PRSW), end-diastolic pressure-volume relationship (EDPVR) and Tau (p<0.01).

Polarized state enhanced phosphorilation of myocardial ERK1 and 2 and Akt, resulting in a lower apoptotic index (TUNEL, p<0.01).

CONCLUSIONS:
Polarized state induced by adenosine, lidocaine and magnesium increased survival, neurologic outcome and cardiac function after prolonged cardiac arrest treated with ECLS. Moreover it improved cardioprotection through activation of the pro-survival kinases Akt and ERK1/2.
Abstract 20433: Viral Myocarditis: Viral Genome Detection Yield on Endomyocardial Biopsy is Influenced by Methodological Factors
Authors: Carturan Elisa , Rizzo Stefania , Thiene Gaetano , Basso Cristina
Published: July 2021

Introduction:
Myocarditis is diagnosed on endomyocardial biopsy (EMB) by histological, immune-histochemical and molecular techniques to detect viral genomes. The role of EMB for the diagnosis and its contribution to patient management has been addressed by a Consensus document of American and European Cardiovascular Pathology Societies.

Hypothesis:
Different methods of tissue fixation and the number of myocardial samples could impact on viral genome yield on EMB.

Methods:
Consecutive EMBs referred at our Institution for histology/ immunohistochemistry evaluation in the time interval 1996-2012 were enrolled. Molecular investigation by RT-PCR and PCR technique was performed in all EMBs with inflammatory cardiomyopathy diagnosis at histology and immunohistochemistry.

Results:
A total of 467 EMBs have been diagnosed as myocarditis: 79 in pediatric (1 month to 18 years; 47M/ 32F) and 388 adult (19 to 75 years; 256M/132 F) patients (pts.). Viral etiology was identified in 28 (36%) pediatric and 101 (26%) adult pts, and the most prevalent type of viruses were enterovirus (8/28, 36%; 26/101, 24%). In a more recent subgroup of 137 EMBs (virus positive 30/137, 22%) seasonality, type of fixation and number of EMB samples were assessed. The seasonal distribution of myocarditis was higher in winter than in other seasons (33% vs. autumn 28%, spring 20% and summer 19%) without any significant difference in terms of virus positive EMBs. The number of EMB samples per pt. was ≤3 (either formalin or RNAlater) in 94/137 (69%) and >3 in 43/137 (31%), with a lower prevalence of virus positive in the former (17/94, 18% vs. 13/43, 30%). Eighty-one EMB samples were frozen while 56 were paraffin embedded, with a higher prevalence of viral genome in the former (26/81, 32% vs. 4/56, 7%; p=0.001).

Conclusions:
The diagnosis of myocarditis on EMB samples requires standardized protocols including molecular techniques. Viral genomes are identifiable in more than one third of pediatric and one fourth of adult cases. Methodological factors like the type of tissue fixation and the number of samples could impact on viral genome detection on EMB.
Abstract 20459: Epigenetic Activation of Phosphodiesterase Subtypes Lead to Compromised Beta-Adrenergic Signaling in Induced Pluripotent Stem Cell-Derived Cardiomyocytes From Dilated Cardiomyopathy Patients
Authors: Wu Haodi , Lee Jaecheol , Gu Mingxia , Lan Feng , Churko Jared , Sanchez-Freire Veronica , Matsa Elena , Ebert Antje , Sallam Karim , Gold Joseph , Wu Joseph
Published: July 2021

Introduction:
Familial dilated cardiomyopathy (DCM) has been modeled by human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). However, the mechanisms of compromised signaling transduction and contractile function in DCM iPSC-CMs are still not well understood.

Methods and Results:
Beating iPSC-CMs were generated from healthy individuals and DCM patients. RNA-seq and real-time PCR showed strict regulation of the main beta-adrenergic signaling proteins in iPSC-CMs during maturation. Confocal imaging of spontaneous calcium activity and hydrogel-based traction force microscopy (TFM) technology demonstrated beta-adrenergic stimulation induced both inotropic and chronotropic regulation in the contractility of iPSC-CMs. Following extended in vitro maturation of iPSC-CMs, we observed a transition in the beta-adrenergic receptor (beta-AR) subtype dependence from beta-2 AR dominance at early stage (day 30) to beta-1/2 AR co-existence at late stage (day 60). Comparison of the beta-adrenergic responsiveness between iPSC-CMs from DCM patients and their familial controls showed compromised beta-adrenergic signaling in DCM cells. Microarray data and expression profiling indicated up-regulated phosphodiesterases (PDE) 2A, 3A and 5A in DCM iPSC-CMs, which impaired cAMP generation and blunted the beta-adrenergic response. By blocking PDE2A, 3A or 5A, beta-adrenergic signaling reactivity and contractile function in DCM iPSC-CMs were both greatly improved. To further elucidate underlying mechanism of PDE regulation, we conducted chromatin immunoprecipitation (CHIP) assays, which showed significant up-regulation of activation histone marker and down-regulation of repressive histone marker in the PDE promoters during maturation process of DCM iPSC-CMs, which closely recapitulated the epigenetic modulation in the ventricle tissues harvested from DCM patients.

Conclusions:
Patient-specific DCM iPSC-CMs recapitulated impaired beta-adrenergic responsiveness and contractility in diseased heart. Studies on iPSC-CM model revealed a novel epigenetic mechanism that underlies PDE subtype specific regulation and signaling deficiency in DCM pathogenesis, which may serve as a new therapeutic target in the future.
Abstract 20484: Enah/Vasp-Like Protein is a Critical Component in S1P-Mediated Endothelial Lamellipodia Formation
Authors: Mascarenhas Joseph B , Mouneimne Ghassan , Gregorio Carol C , Brown Mary E , Wang Ting , Dudek Steven M , Garcia Joe G
Published: July 2021

Ena/VASP like protein, or EVL, is an actin-binding protein that regulates cancer cell lamellipodia protrusive activity and cell motility via an actomyosin contractility-dependent mechanism. The function of EVL in human lung endothelial cell (EC) barrier regulation, especially by the endogenous bioactive lipid mediator sphingosine-1-phosphate (S1P), is largely unknown. In this current study, we demonstrated that EVL is an active component in S1P-mediated EC barrier enhancement and lamellipodia formation. Compared to other focal adhesion (FA) proteins such as paxillin, EVL protein expression is very low in human pulmonary endothelial cells (ECs). S1P (1 μM) challenge stimulates translocation of cytosolic EVL to FAs in ECs, which was attenuated by EVL knockdown (KD) by its selective siRNA. S1P also promoted significant EVL translocation to lamellipodia, further confirmed by tracking translocation of EVL-GFP fusion protein upon S1P stimulation in a time-dependent manner. In addition, S1P-mediated cortical actin filament formation is attenuated by EVL KD, further confirming the function of EVL in S1P-induced lamellipodia formation/cortical actin polymerization. S1P stimulates EVL phosphorylation by tyrosine kinase c-Abl which is attenuated by the c-Abl inhibitor, imatinib. Finally, EVL KD attenuated S1P-mediated EC barrier enhancement and paracellular gap resealing reflected by reduced transendothelial electrical resistance (TER) measurements. These findings confirm a novel role for EVL in human lung vascular barrier enhancement and cytoskeleton rearrangement by S1P.
Abstract 205: Variability of Chest Compression Duty Cycle in the Treatment of Out-of-Hospital Cardiac Arrest
Authors: Cutler Jessica A , Salcido David D , Menegazzi James J
Published: July 2021

Background:
The duty cycle (DC) of cardiopulmonary resuscitation (CPR), which, from the start of one compression to the start of the next compression, describes the proportion of time spent compressing the chest downward, may be useful for characterizing CPR quality. Fifty percent is considered an optimal CPR DC, but little is known about real world DC characteristics.

Objective:
To describe DC characteristics of CPR delivered during the treatment of out-of-hospital cardiac arrest (OHCA).

Methods:
Defibrillator download files for cases of OHCA treated by emergency medical services (EMS) between 2006 and 2008 were obtained from the Pittsburgh regional clinical center of the Resuscitation Outcomes Consortium (ROC), a multi-center clinical research network. Compression depth data were imported into custom software, screened for artifacts, and then parsed and analyzed to establish start, end, and maximum depth for each compression. DC was calculated as the proportion of a compression prior to maximum depth. Descriptive statistics were reported for compression depth in centimeters, rate in compressions per minute (CPM) and DC, averaged over each minute of CPR for up to 30 minutes. Generalized estimating equations (GEE) were used to model the relationship between DC and rate, depth and time.

Results:
The 328 cases included in this study had a mean (SD) age of 64.9 (16.7) years and were predominantly male (61.9%, SE: 2.7). A total of 393,013 analyzable compressions were detected. Figure 1 shows the average CPR DC, rate and depth over the first 30 minutes. Average DC for this period ranged from 44.0% to 46.7%. Mean (SD) DC for the entire 30 minute period was 45.6% (5.2). In a GEE model, DC was inversely related to rate (coeff: -0.0004, p<0.001) and time (coeff: -0.0006, p<0.001), but directly related to depth (coeff: 0.0038, p<0.001).

Conclusions:
DC in EMS-treated OHCA cases was less than the 50% standard, decreased over time, and correlated with both compression rate and depth.
Abstract 20606: Comparison of Saphenous Vein Graft Occlusion and Stent Thrombosis: Discrepancies in Clinical Presentation, Procedural Characteristics and Clinical Outcomes
Authors: Ota Hideaki , Lhermusier Thibault , Magalhaes Marco A , Minha Sa`ar , Pendyala Lakshmana K , Baker Nevin C , Escarcega Ricardo O , Tian Wenjie , Torguson Rebecca , Chen Fang , Satler Lowell F , Suddath William O , Pichard Augusto D , Waksman Ron
Published: July 2021

Background:
Difference in technical complexity and clinical outcomes between percutaneous coronary intervention (PCI) for stent thrombosis (ST) and PCI for occluded saphenous vein graft (SVG) have not been systematically examined. The aim of this study was to compare clinical presentation, procedural characteristics and clinical outcomes of acute coronary syndrome (ACS) patients who underwent PCI motivated by ST with those whom PCI was motivated by SVG total occlusion.

Methods:
We retrospectively included all the patients admitted for ACS due to ST (ST group; n=136) or SVG occlusion (SVG group; n=279) in our institution. The SVG group was divided into the following two subgroups; patients who underwent PCI in the SVG (SVG-PCI; n=75) and those who underwent PCI in native coronary arteries (native-PCI; n=204). Clinical presentation, procedural characteristics and short-term mortality were compared between the 3 groups (ST vs SVG-PCI vs native-PCI).

Results:
Compared with the SVG-PCI and native-PCI groups, acute myocardial infarction (76.5% vs 58.7% vs 30.4%, p <0.001; respectively) and cardiogenic shock (24.3% vs 6.8% vs 3.5%, p <0.001; respectively) were more frequent in the ST group. Concerning procedural characteristics, SVG-PCI group had the highest number of guiding catheter, procedural time, fluoroscopic time and contrast amount, as well as the lowest angiographical success rate (Table). Patients of the ST group had the highest in-hospital mortality and a trend toward higher 30-day mortality (Table).

Conclusions:
The present study suggests that ST when compared to SVG occlusion although easier to treat is associated with a worse outcome especially with respect to the clinical presentation at the time of the event.
Abstract 20661: Vitamin D Deficiency, Tumor Necrosis Factor-Alpha, and Event-Free Survival in Patients With Heart Failure
Authors: Song Eun Kyeung , Moser Debra K , Lennie Terry A
Published: July 2021

Background:
Vitamin D is related to tumor necrosis factor-alpha (TNF-α), a proinflammatory cytokine that predicts cardiovascular disease. However, whether low vitamin D intake is associated with TNF-α and event-free survival in patients with heart failure (HF) has not been examined.

Purpose:
To determine whether association of TNF-α with event-free survival differs between patients with vitamin D adequacy and deficiency.

Methods:
A total of 146 patients with HF (age 63±11 years, 34% female) provided blood to measure serum TNF-α and were divided into 2 groups by median value. Nutrition Analysis program was used to determine intake of vitamin D through a 3-day food diary. Patients with > 80% probability of deficiency were defined as having a diet deficient in vitamin D. Covariate data on age, gender, body mass index, etiology, NYHA class, ejection fraction, comorbidities, and prescribed medications were obtained from review of medical records. Patients were followed for 1 year to determine time to first event of hospitalization or death. Hierarchical logistic and Cox regression was used to address purpose.

Results:
Eighty-five patients (58%) had vitamin D deficiency. During 1-year, 40 patients (27%) were hospitalized or died. Vitamin D deficiency was associated with higher level of TNF-α (OR=3.10, 95% CI=1.32-7.26). In patients with vitamin D deficiency, higher level of TNF-α (HR=3.08, 95% CI=1.06-8.89) predicted shorter event-free survival after controlling for all covariates, whereas there was no difference in event-free survival between higher and lower level of TNF-α in patients with vitamin D adequacy (
p
= .985) .

Conclusions:
The data suggest that one possible mechanism by which vitamin D deficiency contributed to poor health outcomes is through inflammatory pathways in HF patients. Future study is required to determine whether vitamin D adequacy could play a protective role in the impact of proinflammatory cytokines on event-free survival in HF patients.
Abstract 229: Differences in Utilization of Postarrest Care Based on Initial Rhythm
Authors: Grossestreuer Anne V , Perman Sarah M , Abella Benjamin S , Wiebe Douglas J , Leary Marion , Fuchs Barry D , Gaieski David F
Published: July 2021

Background:
Care of successfully resuscitated patients is highly variable. Whether initial rhythm is associated with receiving specific post-arrest interventions has not been explored.

Objectives:
Determine which specific post-arrest interventions are used in patients who remain comatose after resuscitation and whether use is associated with initial arrest rhythm.

Methods:
We included comatose post-arrest patients at 27 hospitals between 2000-2014. We examined patient and arrest characteristics and the use of specialist consultations, cardiac catheterization (cath) and electrophysiology (EP) assessments and interventions, targeted temperature management (TTM), EEG monitoring, head CT and MRI scans, echocardiography, withdrawal of life sustaining therapy (WLST) and length of stay, stratified on initial rhythm.

Results:
A retrospective cohort of 1923 patients was 57% male with a mean age of 62±16 yrs. Of 645 (34%) pts with a shockable initial rhythm, 51% survived to hospital discharge, 89% discharged with CPC 1-2. Of 1278 (66%) pts with a non-shockable initial rhythm, 26% survived to hospital discharge, 73% discharged with CPC 1-2. Patients with initial shockable rhythms were significantly (p<0.05) more likely to have cardiology consults, EEGs, brain MRI scans, echocardiography, TTM, ICDs placed, cath and EP lab visits, longer hospital stays, and not to have WLST than patients with initial non-shockable rhythms. Controlling for cardiac etiology and TTM in logistic regression, cardiology consults, cath and EP lab visits, ICD placement, brain MRIs, echocardiography, and WLST remained significantly different between patients based on initial rhythm (Table 1).

Conclusions:
Post-arrest care varies between patients and can be influenced by arrest characteristics, such as initial pulseless rhythm. Patients with shockable rhythms are more likely to receive certain post-arrest interventions and testing than patients with non-shockable rhythms.
Abstract 230: Factors Associated with Postarrest Withdrawal of Life-Sustaining Therapy
Authors: Grossestreuer Anne V , Gaieski David F , Abella Benjamin S , Wiebe Douglas J , Haukoos Jason S , Perman Sarah M
Published: July 2021

Background:
Most successfully resuscitated cardiac arrest patients do not survive to hospital discharge. Many of those have withdrawal of life sustaining therapy (WLST) as a result of a poor neurologic prognosis.

Objectives:
Determine characteristics of patients who have WLST post-arrest and the differences in their post-arrest care.

Methods:
We identified comatose post-arrest adult patients from 27 hospitals between 2000-2014. We stratified patients by whether they had WLST and analyzed demographic, arrest, and post-arrest variables.

Results:
Of 1439 patients analyzed, 558 (39%) patients had WLST. These patients differed in demographic, arrest, and post-arrest characteristics and treatments (Table 1). In multivariate regression analysis, patients who had WLST were more likely to have post-arrest neurology consults (OR 3.5; 95% CI: 2.3-5.3), less likely to go to the cardiac catheterization (OR 0.3; 95% CI: 0.2-0.5) or electrophysiology labs (OR 0.3; 95% CI: 0.1-0.8), and had shorter hospital stays (OR 0.9; 95% CI: 0.8-0.9). When multivariate regression was limited to patient demographics and arrest characteristics, patients with WLST were older (OR 1.01; 95% CI: 1.00-1.02), had longer downtime (OR 1.01, 95% CI: 1.01-1.02), were more likely to be female (OR: 1.5; 95% CI: 1.2-2.0), were less likely to have an initial rhythm of VF/VT (OR 0.5; 95% CI: 0.4-0.7), and were less likely to have a witnessed arrest (OR 0.7; 95% CI: 0.5-0.9). Patients were less likely to have WLST at an academic medical center (OR 0.6, 95% CI: 0.4-1.0, p=0.04).

Conclusions:
Comatose post-arrest patients who had WLST in the hospital were older, were more likely to have a longer arrest downtime, be female, have an initial non-shockable rhythm, have an unwitnessed arrest, and less likely to be at an academic medical center. They are more likely to have post-arrest neurology consults, less likely to go to the cardiac catheterization or electrophysiology labs, and have a shorter hospital stay.
Abstract 236: Regional Incidence and Outcome of Out-of-Hospital Cardiac Arrest Associated with Overdose
Authors: Salcido David D , Koller Allison C , Torres Cesar D , Orkin Aaron M , Schmicker Rob H , Morrison Laurie J , Nichol Graham , Stephens Shannon W , Menegazzi James J ,   The Resuscitation Outcomes Consortium Investigators
Published: July 2021

Introduction:
The frequency of lethal overdose due to prescription and non-prescription drugs is increasing in North America. The contribution of drug overdose (OD) to regional variation in the incidence and outcome out-of-hospital cardiac arrest (OHCA) is unclear.

Objective:
To estimate overall and regional variation in incidence and outcomes of emergency medical services (EMS)-treated OD-OHCA cases across North America.

Methods:
The Resuscitation Outcomes Consortium (ROC) is a clinical research network with 10 regional clinical centers in United States (US) and Canada that uses uniform methods for surveillance of all EMS-treated OHCA in participating regions. Cases of OHCA from 2006 to 2010 were reviewed for evidence of association with or without OD. Incidence of OD-OHCA was calculated as the number of OD-OHCA in a region per 100,000 cumulative person-years, using 2000 US Census and 2006 Statistics Canada population counts. Patient and EMS characteristics as well as outcome were described. Multiple logistic regression was used to describe the association between OD status on return of spontaneous circulation (ROSC) and survival to hospital discharge, while adjusting for case characteristics and consortium center.

Results:
Included were 56,272 cases of OHCA. Regional incidence of OD-OHCA varied between 0.5 and 2.7 per 100,000 person years (p<0.001), and proportion of OD-OHCA among all EMS-treated OHCA ranged from 0.9% to 3.8%. Table 1 shows outcomes and characteristics stratified by OD status; OD-OHCA were younger, less likely to be witnessed, and less likely to present with a shockable rhythm. Compared to non-OD, OD-OHCA was associated with ROSC (OR: 1.55; 95%CI: 1.35-1.78) and survival (OR: 2.14; 95%CI: 1.72-2.65).

Conclusions:
OD-OHCA are a small proportion of all OHCA, although incidence varied up to 5-fold across regions. OD-OHCA were more likely to survive than non-OD-OHCA.
Abstract 237: Comparative Efficacy of Biphasic Waveform Defibrillation Energies for In-Hospital Cardiac Arrest: Insights from the Get With The Guidelines--Resuscitation Registry
Authors: Schneider Preston M , Liu Wenhui , Grunwald Gary K , Chan Paul S , Nallamothu Brahmajee K , Sasson Comilla , Varosy Paul D , Turakhia Mintu P , Ogunnaike Babatunde , Bradley Steven M
Published: July 2021

Background:
Biphasic waveforms have become the predominant choice for defibrillation of cardiac arrest due to pulseless ventricular tachycardia or ventricular fibrillation (VT/VF). However, little is known about the relative efficacy of different first shock energy levels for defibrillation of VT/VF.

Methods:
Within the Get With The Guidelines - Resuscitation multicenter observational registry, we identified adults who received biphasic waveform defibrillation for in-hospital cardiac arrest due to VT/VF between 2005 and 2012. Using hierarchical regression to adjust for patient arrest characteristics and comorbidities while accounting for clustered observations by hospital, we examined the risk-adjusted association between the energy level (100J, 120J, 150J, 200J, 300J, or 360J) of the first defibrillation attempt and patient outcomes. Our primary outcome was termination of VT/VF following the first shock, with secondary outcomes of return of spontaneous circulation (ROSC), 24 hour survival, and survival to discharge.

Results:
Among 12,417 adults suffering VT/VF arrest treated with biphasic defibrillation, the most common first shock energy was 200 J (55.5%) Compared with 200 J, defibrillation with 120 J was more likely to result in termination of VT/VF and 24 hour survival and 150J was associated with greater 24 hour survival and survival to discharge. In contrast, energies higher than 200 J showed no difference in termination of VT/VF, but were associated with lower survival (see Table).

Conclusion:
Among adults with in-hospital cardiac arrest due to VT/VF, defibrillation with 200 J is the most common energy used for initial defibrillation with a biphasic waveform. However, initial defibrillation with lower energy levels is associated with greater odds of VT/VF termination, 24 hour survival, and survival to discharge. Further study is needed to inform the optimal energy for initial defibrillation of cardiac arrest due to VT/VF.
Abstract 240: Concomitant Use of Therapeutic Hypothermia with Mechanical Circulatory Support in Patients Post Cardiac Arrest in Cardiogenic Shock: A Single Center Experience
Authors: Silverman Michael G , O’Brien Molly H , Avery Kathleen R , Chase Annmarie , Pierce Carol D , Griswold Karen , Henderson Galen V , Hirning Beth Anne , Kyller Michael , Massaro Anthony F , Seethala Raghu , Stone Peter , Strojwas Stefan , Szumita Paul , Morrow David A , Scirica Benjamin M
Published: July 2021

Background:
The concurrent use of therapeutic hypothermia (TH) following cardiac arrest and mechanical circulatory support (MCS) for cardiogenic shock is becoming increasingly common. Little is known however, about the combined use of TH and MCS for patients after ROSC following a cardiac arrest who remain in cardiogenic shock. Therefore we describe the experience with concomitant use of TH and MCS from a large academic tertiary care center in Boston.

Methods:
Baseline characteristics and clinical outcomes at hospital discharge were reported for patients undergoing TH following cardiac arrest who also received MCS for cardiogenic shock. MCS included Intra-aortic balloon pump (IABP) two percutaneous ventricular assist devices (Impella, and TandemHeart), and extracorporeal membrane oxygenation (ECMO). Clinical outcomes included mortality as well as cerebral performance category (CPC) at hospital discharge.

Results:
There were a total of 14 patients who underwent concomitant TH and MCS following a cardiac arrest. Baseline characteristics and clinical outcomes are noted in the Figure. 9 patients underwent placement of IABP, 2 patients an Impella pump, 2 patients a TandemHeart, and 1 patient ECMO. All 14 cardiac arrests were due to cardiovascular etiologies; 9 of 14 had STEMI. 9 of 14 patients had an initial shockable rhythm. Mean age was 56 years (+/- 19), mean downtime was 35 minutes (+/- 24). All patients were vasopressor dependent. Bleeding events are noted in the table. 8 patients survived to hospital discharge, all with good neurologic outcome. These rates were comparable to the survival rates and neurologic outcomes among 82 patients who underwent TH post cardiac arrest (from cardiovascular etiologies) without concomitant MCS (Figure).

Conclusion:
Based on our experience from a large academic tertiary care center, concomitant use of TH and MCS is both safe and feasible with an encouraging rate of cardiac and neurologic recovery.
Abstract 273: Knowledge of First Aid and Cardiopulmonary Resuscitation by Faculty and Staff of Public Schools in São Paulo
Authors: Assis Nilton F , Liberato Isadora , Mathey Ana Laura , Gianotto-Oliveira Renan , Oliveira Gustavo G , Gonzalez Maria M , Timerman Sergio , Kalil Filho Roberto
Published: July 2021

Background:
Knowledge of first aid and cardiopulmonary resuscitation (CPR) is very important in schools, where children, teens and even employees are subject. Our objective was to evaluate the knowledge of teachers and employees of public schools in São Paulo on first aid and CPR with automated external defibrillator (AED).

Methods:
A questionnaire on the content that is covered in the course of First Aid from the American Heart Association was applied to faculty and staff of public schools in São Paulo. After answering the questionnaire, all volunteers took the course First Aid with CPR and AED.

Results:
The study included 563 volunteers: 227 (40%) teachers and 336 (60%) school staff. The mean age was 42 ± 12 years, 101 (18%) were male and 80 participants (14%) had already done a course in First Aid and / or CPR. The mean number of correct answers was 6.5 (46%) in a total of 14 questions. The questions with the greatest number of errors were: frequency of chest compressions (82%), depth of chest compressions (78%), handling of automated external defibrillator (77%), what to do with an unconscious victim (64%), compression ratio and ventilation (61%), conduct on a victim with nosebleed (53%) and conduct on a victim with convulsion (52%). When asked if they were interested in doing a course in first aid, 95% answered yes, 89% believe that the contents of first aid should be placed in the grade of students albeit in a simplified manner.

Conclusion:
We conclude that the degree of knowledge of teachers and employees of public schools in São Paulo is quite insufficient, although the vast majority has an interest in pursuing a course that addresses the topic of first aid and CPR with AED. It would therefore be very interesting that the government underscored the importance of the subject and stimulate training for teachers, school staff and students.
Abstract 283: Hands-off Time During Lay Rescuer Basic Life Support Remains High After a Standard Basic Life Support Course
Authors: Mueller Michael , Rudolph Christian , Poenicke Cynthia , Eichelkraut Andre , Papkalla Norbert , Karg Susann , Richter Torsten
Published: July 2021

The current international guidelines for resuscitation recommend high quality chest compressions with minimal interruptions as important prerequisite for optimal survival after cardiac arrest. During the standard four hours BLS course of the European Resuscitation Council (ERC) the participants learn to provide chest compressions, ventilations and to use an automated external defibrillator. We know that lay rescuers are able to learn these skills. However, it is unclear whether lay rescuers manage to minimize interruptions of chest compressions.

Objective:
To evaluate the no-flow fraction (NFF) during lay rescuer BLS including chest compressions, ventilation and the use of an AED.

Methods:
24 participants of a BLS/ AED course were assessed before (T1) and after (T2) the BLS training in a standardized scenario in pairs of 2 rescuers. We used a Resusci Anne Simulator manikin (Laerdal, Norway) and a Lifepak 1000 AED trainer device for the assessment. The scenario was an adult patient with cardiac arrest and persistent ventricular fibrillation (VF), duration of the scenario was 5 minutes. 28 lay persons served as control group and were assessed in pairs of 2 rescuers twice at the same day. Two-sided t-test was used to test differences between groups and between test scenarios (T1 vs. T2), p<.05 was considered significant.

Results:
The NFF decreased from 0.68 ± 0.1 (before the course) to 0.5 ± 0.07 (after the course), p=.000. In the control group the NFF was 0.63 ± 0.1 (scenario 1) and 0.59 ± 0.14 (second scenario), p=.244.

Conclusion:
A standard BLS course reduces the interruptions of chest compressions during lay rescuer CPR. However, 50% of the scenario no chest compressions are given. Interruptions are mainly due to ventilations or related to the use of the AED. Further research is necessary to improve the BLS algorithm regarding reduction of interruptions.
Abstract 290: Cardiopulmonary Resuscitation Duty Cycle in Out-of-Hospital Cardiac Arrest
Authors: Rea Thomas , Johnson Bryce , Coult Jason , Fahrenbruch Carol , Blackwood Jennifer , Sherman Lawrence , Kudenchuk Peter , Sayre Michael
Published: July 2021

Background:
CPR duty cycle is the portion of time spent in compression relative to the total time of the compression-decompression cycle. Guidelines recommend a 50% duty cycle based largely on animal investigation. Little is known about duty cycle in human resuscitation and whether duty cycle correlates with other CPR measures.

Methods:
We calculated the duty cycle, compression depth, and compression rate during EMS resuscitation of 164 patients with out-of-hospital ventricular fibrillation cardiac arrest. We captured force recordings from a chest accelerometer to measure ten-second CPR epochs that immediately preceded each scheduled rhythm analysis. Duty cycle was calculated using two methods. The effective compression time (ECT) is the time from beginning to end of compression divided by total period for that compression-decompression cycle. The area duty cycle (ADC) is the ratio of area under the force curve divided by total area of one compression-decompression cycle. We evaluated the compression depth and compression rate according to duty cycle quartiles.

Results:
There were 369 ten-second epochs among 164 patients. The median duty cycle was 38.8% (SD=5.5%) using ECT and 32.2% (SD=4.3%) using ADC. A relatively shorter compression phase (lower duty cycle) was associated with greater compression depth (test for trend < 0.05 for ECT and ADC) and slower compression rate (test for trend < 0.05 for ADC) (Table). Sixty-one patients (37%) survived to hospital discharge.

Conclusions:
In this system with high survival, duty cycle was well below the 50% recommended guideline, and was associated with compression depth and rate. These findings provide rationale to incorporate duty cycle into future research to evaluate how CPR influences resuscitation.
Abstract 291: Interaction Between Diabetes and Hypothermia on Outcomes After Out-of-Hospital Cardiac Arrest: A Nationwide Observational Study
Authors: Ro Young Sun , Shin Sang Do , Song Kyoung Jun , Lee Eui Jung
Published: July 2021

Objective:
To determine whether diabetes mellitus (DM) has an interaction effect with the mild therapeutic hypothermia (MTH) on brain recovery after emergency medical services (EMS) assessed out-of-hospital cardiac arrest (OHCA) survivors.

Methods:
We included all OHCA patients survived to admission with presumed cardiac etiology (Jan. 2009 to Dec. 2012) from Korean national OHCA registry, excluding cases without available outcome data. The primary exposure was MTH which included all kinds of cooling methods. The endpoints were hospital discharge and discharge with brain recovery (cerebral performance category 1 or 2). DM was defined as PDM-positive when the patient has clinical treatment history or positive at blood laboratory test, NDM- negative in history and test, and UDM- if there is no available laboratory test and history. We compared outcomes between MTH versus non-MTH group using multivariable logistic regression with interaction term between MTH and DM for calculating adjusted odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for individual, Utstein, post-resuscitation factors, and comorbidities.

Results:
We included 7,516 OHCAs survived to admission. MTH was performed in 14.6% and showed better outcomes than non-MTH group; 54.1% vs. 36.4% in survival discharge and 22.6% vs. 14.1% in good brain recovery (Ps<0.001). Survival to discharge with good brain recovery of all and DM group was 15.3% of all (n=7,516), 17.7% of NDM (n=4,129), 9.7% of PDM (n=1,952), and 16.1% of UDM (n=2,382), respectively. MTH performed has increased by year; 8.6% (2009), 9.9% (2010), 16.1% (2011), and 21.1% (2012). Adjusted OR (95% CI) by MTH for survival to discharge was 1.66 (1.42-1.95) in non-interaction model and 2.08 (1.55-2.81) in NDM, 1.24 (0.88-1.75) in PDM, 1.84 (1.23-2.61) in UDM in interaction model, respectively. Adjusted OR (95% CI) by MTH for discharge with brain recovery was 1.29 (1.04-1.56) in non-interaction model and 1.33 (0.87-2.02) in NDM, 0.59 (0.34-1.04) in PDM, and 0.62 (0.36-1.03) in UDM in interaction model, respectively.

Conclusions:
The MTH was associated with better outcomes and is significantly associated with survival to discharge in non-diabetes group, not in diabetes group.
Abstract 315: Three-Year Survey in Ishikawa Prefecture of Nontraumatic Aneurysm and Dissection of the Aorta Not Followed by Out-of-Hospital Cardiac Arrest in Patients Who Were Transported by Emergency Medical Technicians
Authors: Inaba Hideo , Nishi Taiki , Kamikura Takahisa , Matsubara Hiroki , Yamashita Akira , Hashimoto Masaaki
Published: July 2021

Aim:
To investigate the signs, symptoms and incidences of aortic aneurysm/dissection (A/D) that did and did not cause OHCA and were transported by EMTs.

Materials and Methods:
Fire departments prospectively collected the data for cases with non-traumatic aortic A/D that were transported by EMS during the period of 2011 to 2013. The data included the backgrounds, signs and symptoms of the patients at the scene, backgrounds of the bystanders and 1-month survival.

Results:
As shown in Fig. 1, of 219 cases transported by Emergency Medical Technicians (EMTs) on their suspicion of aortic A/D, 140 cases were diagnosed with aortic A/D. Of 72,185 cases with endogenous medical emergency, 176 cases transported without EMT’s suspicion of aortic A/D were finally diagnosed with aortic aneurysm/dissection. In total, 316 cases had the aortic A/D. Thus, sensitivity of our regional EMS for non-traumatic aortic AD was 44% (140/316) while positive predictive value was 64% (140/219). The backgrounds of patients are as follows: male gender (51%), median value (25-75%) of age [73 (62-83)], high co-morbidity (88%). The major signs and symptoms obtained by EMTs were characterized by acute onset but mostly non-specific: chest pain (45%), back pain (40%), abdominal pain (14%). Moving severe pain was rarely caught (6%). These symptoms happened without a hard exercise (99%), and detected mainly by family members (41%) and patients themselves (34%). Bilateral blood pressure difference was rarely detected (5%). One-month survival rate was higher in cases transported to major emergency medical hospitals offering a major vascular surgery than those to other hospitals. None of other factors were associated with the survival.

Conclusions:
The Incidence of aortic A/D in all medical emergencies was extremely low. The survival rate may depend on the level of transported hospital. Clear criteria for “aortic transportation bypass” is required in EMS system.
Abstract 327: Basic Life Support and Defibrillation Are Changing the Prognosis of Hypertrophic Cardiomyopathy in School Students
Authors: Ayusawa Mamoru , Kato Masataka , Chou Ami , Watanabe Hirofumi , Komori Akiko , Abe Yuriko , Kamiyama Hiroshi , Sumitomo Naokata , Takahashi Shori
Published: July 2021

OBJECTIVES:
Hypertrophic cardiomyopathy (HCM) has been one of the leading causes of sudden cardiac death in school students. However, recent spread of basic life support combined with public access defibrillation and implantable cardioverter-defibrillator (ICD) has a possibility of a paradigm shift for prognosis of HCM in young.

METHODS:
In Japan, more than 98% of all students in primary, middle, and high schools subscribe in the mutual aid system, and a school that experienced event relating sudden death is obliged to submit all health checking documents to refund for the affected student. Submitted reports were investigated for 8 years between 2004 and 2011. All victims or survivors diagnosed as HCM were extracted from those reports. Demographic data, presence of diagnosis before event, and intensity of physical activity at event were compared between them.

RESULTS:
Though data in 2011 is still tentative, annual numbers of victims with HCM from 2004 to 2011 were 4, 4, 5, 6, 3, 2, 4, 1, respectively. The first resuscitated survivor with HCM was reported in 2007, thereafter from 2008 until 2011, those were 6, 2, 4, 2, respectively. Therefore, totals of 29 victims and 15 survivors were enrolled in this study. All survivors were middle or high school students. Three primary school students were all victims. The male-to-female ratio was 4.8 and 2.0, respectively (NS). Ratio of students who were previously diagnosed as HCM was 48% and 20%, respectively (p=0.06). Concerning exercise intensity at cardiac event, 24% and 6.7% were occurred without exercise, respectively (p=0.08). ICD insertion after successful resuscitation was reported in 80% of survivors.

CONCLUSIONS:
Induction of basic life support and defibrillator has a certain impact for increasing survivors with HCM in school students. After 2008, survivors become equal or more than victims. Majority of survivors were disclosed by initial cardiac event by strenuous exercise, and cardioverter-defibrillator was implanted after resuscitation. Strategy for survival of HCM students with previously diagnosed should be reviewed. School caregivers including general physicians should acquire the management of students with ICD.