bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 20209: Spontaneous Post Myocardial Infarction Arrhythmia is Potentiated by Calcium Alternans in Type I Diabetic Akita Mice
Authors: Jin Hongwei , Park Ho-Jin , Aronovitz Mark J , Wang Bo , Zhang Yali , Link Mark , Noujaim Sami , Galper Jonas
Published: July 2021

Introduction:
Myocardial infarction (MI) is the most common cause of mortality in diabetes. Diabetics have been shown to be twice as likely to die suddenly from MI out of hospital compared to non diabetic patients. The mechanism of sudden death in the diabetic population is unclear. Here we use the Akita Type I diabetic mouse as an animal model for the study of post MI ventricular tachycardia arrhythmias (VT) and the role of abnormalities of Ca2+ homeostasis in the pathogenesis of post MI VT.

Methods:
To determine the effect of MI on the incidence of VT, EKG transmitters were implanted into WT and Akita mice. MIs were generated by permanent ligation of the left coronary artery resulting in infarctions affecting more than 30% of the LV as demonstrated by echocardiographic analysis and TTC staining. Dual calcium-voltage optical mapping was performed on the isolated Langendorf heart after MI. Left ventricular myocytes were isolated for calcium imaging studies. Sarcomere shortening and Ca2+transients were measured by Ionoptix system and Ca2+ sparks by confocal microscopy.

Results:
Compared to WT, Akita diabetic mice developed a high incidence of non sustained and sustained VT in the first 30h post MI peaking at 18 h. Epicardial optical mapping demonstrated pacing induced: Ca2+ alternans which was most marked in the peri-infarction zone of Akitas and VT also originating in the peri-infarction zone in the Akita mice, but not in WT. Single cardiomyocytes from Akita displayed both contractile and Ca2+ alternans when pacing rate was increased above 3Hz, but none in cells from WT mice. Ca2+ imaging studies were performed to determine whether alterations in Sacroplasmic reticulum(SR) Ca2+ function contributes to Ca2+ alternans. In Akita myocytes, Ca2+ transient decay time( Tau) was significantly increased ( 0.171±0.01s, N=23 ) compared to WT(0.139±0.007s, N=20, P<0.05), The frequency of spontaneous Ca2+ sparks in Akita mocytes increased from 0.043 ± 0.003 sparks/100μm/s (N=23) in the WT to 0.266 ± 0.023 sparks/100μm/s ( P<0.05, N=36).

Conclusions:
The type 1 diabetic Akita mice demonstrate a high incidence of spontaneous post MI VT associated with pronounced Ca2+ alternans in the peri-infarction zone and abnormalities of Ca2+ homeostasis.
Abstract 20243: Differential Uptake of Omega-3 Polyunsaturated Fatty Acids in Trial Subjects Could Explain Variability of the Trials’ Outcome
Authors: Shaikh Nisar A , Shaikh Sabah N , Yantha Jason , Jackowski George
Published: July 2021

Background:
A relationship of regular fish consumption with lowered incidence of cardiovascular disease (CVD) has been appreciated for decades. However, preparations from fish oils, showed mixed results in recent meta-analyses and have raised some doubts on the efficacy of omega-3 polyunsaturated fatty acids (ω-3 PUFA) for management of CVD. Some of these reports suffer from inclusion of studies with ill-defined patient populations, varying PUFA doses, purity, and formulation, while others have patients on drug milieu or have employed placebo that could have undermine the trial outcome. Very few studies have determined ω-3 PUFA levels pre & post treatment. In this report, we are the first to describe heterogeneity of Omega 3 uptake among trial subjects that could have contributed to the inconsistencies of results.

Methods:
In VASCAZEN-REVEAL trials, 54 subjects with normal to high blood triglycerides levels (TG 90-500mg/dl) and with ω-3 PUFA deficiency (Omega-Score™, OS, blood levels of eicosapentaenoic (EPA)+docosahexaenoic (DHA) +docosapentaenoic acid (DPA) of <6.1% of total blood fatty acids) were provided 4g/day of 6:1 EPA/DHA formulation (>90% purity) for 8 weeks. Changes in the OS levels pre-and post treatment along with individual fatty acids including arachidonic (AA) were determined and desaturation enzymes activities were calculated.

Results:
Based upon post-treatment increases in the blood levels of OS, weak (WR), intermediate (IR) and strong (SR) responders were identified.

Conclusion:
This is the first report to show differential effect of Omega-3 on trial subjects and warrants caution in the interpretation of trial data without identifying the responders.
Abstract 20251: A Novel Role for Brown Adipose Tissue in Cardioprotection
Authors: Thoonen Robrecht , Ernande Laura , Hindle Allyson , Cheng Juan , Chao Wei , Bloch Kenneth D , Buys Emmanuel S , Scherrer-Crosbie Marielle
Published: July 2021

Introduction:
Brown adipose tissue (BAT), upon activation by natriuretic peptides and catecholamines, converts the energy of free fatty acids and glucose oxidation into heat (thermogenesis) through uncoupling protein 1 (UCP1). BAT activation has also been reported to increase triglyceride uptake and improve insulin resistance in obesity.

Hypothesis:
We hypothesized that activated BAT limits myocardial injury and remodeling in a catecholamine-induced cardiomyopathy model.

Methods:
Isoproterenol (ISO, 60 mg/kg/day) or saline were infused in wild type (WT, n=12) and UCP1-deficient (UCP1-/-, n=11) mice for 14 days using an osmotic minipump. Plasma cardiac troponin I levels (cTnI) were measured after 3 days of treatment. Echocardiograms were performed before and after treatment for 14 days. BAT and LV were harvested for RNA and histology. The experiments were repeated in mice that had undergone prior BAT transplantation (WT to WT n=8; WT to UCP1-/- n=7; UCP1-/- to UCP1-/- n=6).

Results:
At baseline LV size, mass and ejection fraction (LVEF) were similar in WT and UCP1-/- mice, cTnI was undetectable. Gene expression in BAT of UCP1-/- mice revealed decreased lipid metabolism and oxidative phosphorylation. After 3 days of ISO treatment plasma cTnI was markedly increased in UCP1-/- mice compared to WT (Table). After 14 days of ISO infusion UCP1-/- mice developed greater LV hypertrophy and fibrosis than WT mice (Table). Transplantation of UCP1-/- BAT to UCP1-/- or WT mice did not decrease isoproterenol-induced cTnI release, however, transplantation of WT BAT to UCP1-/- mice reversed the increased cTnI and adverse remodeling.

Conclusions:
UCP1-deficiency causes BAT dysfunction, and increases cardiomyocyte injury and adverse LV remodeling in a mouse model of catecholamine-induced cardiomyopathy. Cardiomyocyte injury and adverse LV remodeling are rescued by transplantation of functional BAT in to UCP1-/- mice, suggesting that functional BAT is cardioprotective.
Abstract 20326: Impact of Gender on Clinical Outcomes in Non-Valvular Atrial Fibrillation: Contemporary Perspective From the GARFIELD Registry
Authors: Camm John , Goldhaber Samuel Z , Ambrosio Giuseppe , Jansky Petr , Al Mahmeed Wael , Oh Seil , Van Eickels Martin , Raatikainen Pekka , Steffel Jan , Chu Emily , Accetta Gabriele , Kayani Gloria , Kakkar Ajay K ,   for the GARFIELD Investigators
Published: July 2021

Purpose:
To evaluate the influence of gender on baseline characteristics and 1-year clinical outcomes in patients with non-valvular atrial fibrillation (AF).

Methods:
In the ongoing, international registry GARFIELD, a total of 12,458 prospective patients were enrolled at 739 randomly selected sites in 30 countries between March 2010 and January 2013.

Results:
Compared with men, women with AF were more likely to be older and have a history of hypertension or venous thromboembolism, but less likely to have a history of vascular disease. Use of antithrombotic therapy was similar in the two groups. At 1-year follow-up, the hazard ratio for women versus men, adjusted for age group, use of vitamin K antagonist, Factor Xa inhibitor, direct thrombin inhibitor, and antiplatelet, congestive cardiac failure, hypertension, diabetes, stroke/transient ischaemic attack, and vascular disease, was 0.815 (95% confidence interval, 0.695-0.957) for the incidence of all-cause mortality, 1.414 (1.053-1.899) for the incidence of stroke/systemic embolism (SE), and 1.024 (0.714-1.470) for the incidence of major bleeding.

Conclusion:
These findings suggest that women with non-valvular AF have a lower mortality rate despite a higher stroke/SE rate compared with men.
Abstract 20355: Cardiac Magnetic Resonance Assessment of Absolute Myocardial Blood Flow and Myocardial Perfusion Reserve Compared With FFR in Patients With Coronary Artery Disease
Authors: Kanaji Yoshihisa , Lee Tetsumin , Murai Tadashi , Suzuki Asami , Matsuda Junji , Araki Makoto , Kakuta Tsunekazu
Published: July 2021

Background:
The diagnostic value of absolute myocardial blood flow (AMBF) obtained by cardiac magnetic resonance (CMR) quantitative measurement remains uncertain. We evaluated the subendocardial, epicardial, transmural AMBF, and myocardial perfusion reserve (MPR) derived from AMBF determined by perfusion CMR. We also assessed the relationship between CMR-derived AMBF and fractional flow reserve (FFR) in patients with coronary artery disease (CAD).

Methods and Results:
We investigated 38 CAD patients (mean age, 67±10 years; male, 89%, 46 vessels territories) who underwent perfusion CMR both at stress and rest, and invasive coronary angiography. FFR was measured in all vessels with stenosis more than 40% by QCA. FFR<0.8 was considered hemodynamically significant stenosis. Patients with previous revascularization and/or myocardial infarction, and with renal dysfunction were excluded. We perform quantitative analysis of the transmural, subendocardial and epicardial AMBF, and MPR at mid-ventricular level. AMBF distributed in the wide range both subendocardium and subepicardium. At stress, AMBF was significantly increased in all of the subendocardial, epicardial, and transmural layers of the ischemic segment at adenosine-induced hyperemia from rest AMBF. (At rest: subendocardial 245±122 ml/100g/min, epicardial 124 [75-233] ml/100g/min, transmural 172 [102-261] ml/100mg/min. At stress: subendocardial 380 [156-517] ml/100g/min, epicardial 275 [158-502] ml/100g/mintransmural 287 [152-456] ml/100g/min.) There was a significant relationship between transmural AMBF and FFR, transmural MPR and FFR values, with r = 0.33 (p = 0.028), r=0.39 (p=0.007). The transmural MPR<2.47 threshold yielded a sensitivity of 0.92 (95% confidence interval: 0.77 to 0.99) and a specificity of 0.71 (0.44-0.90) to detect coronary ischemia with a FFR <0.8, and an area under the ROC curve (AUC) of 0.77 (0.62 to 0.88) for vessel-based analysis. Subendocardial AMBF and MPR gradually decreased with decreasing FFR at ischemic segment, but it was not significant.

Conclusions:
The quantitative analysis of transmural AMBF and myocardial MPR on perfusion cardiac magnetic resonance may predicts hemodynamically significant CAD as defined by FFR.
Abstract 20445: Pras40 Prevents Development of Diabetic Cardiomyopathy
Authors: Volkers Mirko , Doroudgar Shirin , Glembotski Christopher , Sussman Mark
Published: July 2021

Introduction:
Diabetes is a multi organ disease and diabetic cardiomyopathy can result in heart failure, which is a leading cause of morbidity and mortality in diabetic patients. Defects in mTOR signaling are believed to contribute to metabolic dysfunctions in diabetic liver and hearts, but evidence is missing that mTOR activation is causal to the development of diabetic cardiomyopathy. PRAS40 (Proline Rich Akt Substrate of 40kDa) is a specific component of mTORC1 that interacts with RAPTOR to inhibit mTORC1 kinase activity

Methods and Results:
The db/db mouse exhibits key characteristics of T2DM, namely hyperinsulinemia, insulin resistance, hyperglycemia, and develops diabetic cardiomyopathy with decreased cardiac function. Selective mTORC1 inhibition in cardiomyocytes from db/db mice in vivo was achieved using PRAS40 delivered via recombinant cardiotropic adeno-associated vector serotype 9 (AAV9) driven by a cardiomyocyte-specific myosin light chain (MLC2v) promoter construct. Myocardial dysfunction was prevented in AAV-PRAS40 treated db/db mice compared to the AAV-Control group, as seen by significantly higher cardiac ejection fraction (EF%), fractional shortening (FS%) measured by serial echocardiography, despite similar increases in body weight, serum glucose levels, and fat deposition in the liver. The effects of PRAS40 were tested in a model of T2DM induced by high fat diet (HFD). AAV-PRAS40 or AAV-Control was injected at 7 weeks of age and mice were fed HFD chow of or standard for an additional 25 weeks. Decreased cardiac function was observed in the HFD control group measured by echocardiography. This preservation of function was associated with decreased left ventricular diastolic dimension (LVID) and improved diastolic function. This phenotype was associated with improved metabolic function, blunted hypertrophic growth, and preserved insulin sensitivity.

Conclusions:
mTORC1 inhibition with PRAS40 prevents diabetic cardiomyopathy and improves metabolic function in diabetic mice. These findings may open novel avenues for therapeutic strategies using PRAS40 directed against diabetic-related diseases.
Abstract 20549: Patient-Specific CT Image-Based Engineering Analysis of Transcatheter Aortic Valve Replacement - Implications for Aortic Root Rupture
Authors: Wang Qian , Martin Caitlin , Kodali Susheel , Leipsic Jonathon , Blanke Philipp , Webb John , Leon Martin , Williams Mathew , Primiano Charles , Sun Wei
Published: July 2021

Introduction:
Despite the increased global experience with transcatheter aortic valve replacement (TAVR), there remain major adverse clinical events. One of the most severe complications of TAVR is aortic rupture. Although several clinical risk factors of TAVR-induced rupture have been identified, the mechanisms remain largely unknown. The objective of this study was to use computational models to predict potential aortic rupture in TAVR patients.

Methods:
Pre-procedural CT scans of TAVR patients were used to reconstruct patient-specific finite element (FE) models, which included the aortic root, aortic leaflets, calcification, mitral-aortic intervalvular fibrosa, anterior mitral leaflet, fibrous trigones, and left ventricle. Stent deployment was simulated in a total of 25 patients to evaluate the potential for aortic rupture. Our research design consisted of two phases: Phase One, which was to develop and calibrate FE modeling techniques by retrospectively analyzing 7 Edwards SAPIEN cases with known results; and Phase Two, which was to implement the modeling methodology developed in Phase One to conduct a blind study of 18 cases from a database of 60 patients consisting of 50% rupture cases. For the blind study, FE simulations were completed by researchers blind to the clinical outcomes, and data analysis was conducted by an independent researcher.

Results:
Simulations correctly predicted 83% of the rupture cases. The balloon pressure at time of rupture was approximately 3.52 atm and 2.53 atm for SAPIEN 23 and 26 valves, respectively. The average contact force between the stent and native tissue was about 81N.

Conclusion:
Our analysis of over 18 patients suggested that the TAVR outcome could depend on the patient-specific aortic sinus shape, calcification volume, shape, location, and orientation. These results demonstrate the potential for simulation-based pre-TAVR planning tools to evaluate device performance and improve clinical outcomes.
Abstract 20583: Prehospital Electrocardiogram Transmission is Associated With Decreased First Medical Contact to Device Time in a Large Urban Emergency Medical Services System
Authors: Richards Christopher , Pearlman Ken , Stein-Spencer Leslee , O’Neill Kathleen , Schroff Adhir , Purim-Shem-Tov Yanina , Markul Eddie , Weber Joseph , Miller Art , Magurany Kathleen , Weller Shirley ,   Region XI QI sub-committee, Schaer Gary
Published: July 2021

Introduction:
Early recognition and rapid revascularization is associated with improved outcomes in patients with STEMI. Increasingly, prehospital providers acquire ECGs, transport patients to PCI-ready hospitals, and activate interventional cardiology teams in advance of arrival (“door time”). Therefore, the time from first medical contact (FMC) with either EMS providers or the emergency department may be an important metric for overall system performance in the care of patients with STEMI.

Hypothesis:
A prehospital ECG transmission program will be associated with a decreased median FMC to revascularization device deployment time.

Methods:
A retrospective cohort study of Action Registry-GWTG data in Chicago was performed. The Chicago Fire Department implemented a 12-lead ECG program in 2012. Patients with confirmed STEMI from January through December 2013 were included. A baseline median FMC to device time was determined for the third quarter of 2012, at the start of the ECG program. Descriptive statistics were used for analysis.

Results:
Over the study period, 322 patients experiencing STEMI were treated in 9 hospitals. Patients were predominantly male (66%), and 50% arrived by ambulance. The average median FMC to device time during the study was 83 minutes, which decreased from an initial baseline of 104 minutes. The median time from FMC to door and from catheterization laboratory arrival to device remained constant over the study period (24 minutes and 22 minutes respectively), but the median time from door to catheterization laboratory decreased from 42 minutes to 33 minutes.

Conclusions:
Implementation of a prehospital ECG transmission program was associated with a decreased median FMC to device time in a large city, with FMC to device times consistently less than 90 minutes. The median door to device time for all patients regardless of arrival mode decreased too suggesting improved care processes for all patients with STEMI.
Abstract 20642: Why Arrhythmogenic Cardiomyopathy is Still a Major Cause of Sudden Death in Competitive Athletes Despite Preparticipation Screening?
Authors: Basso Cristina , Rizzo Stefania , Pilichou Kalliopi , Corrado Domenico , Thiene Gaetano
Published: July 2021

Introduction:
The incidence of sudden death (SD) in young competitive athletes has declined in Italy since the introduction of systematic screening including ECG. Mortality reduction was predominantly due to a lower incidence of SD from cardiomyopathies

Hypothesis:
Arrhythmogenic cardiomyopathy (AC) should have also declined as a cause of SD in competitive athletes.

Results:
During the study period 1981-2014, 75 competitive athletes died suddenly. Major causes at postmortem examination were AC, 27%; atherosclerotic coronary artery disease (CAD), 24%; congenital CAD, 16%; normal heart 10%; conduction system disease, 7%; hypertrophic cardiomyopathy, 5%; myocarditis, 4%; mitral valve prolapse, 3%. When analyzing the 26 AC cases, we subdivide those occurring before (group A, n.13 cases) and after 1998 (group B, n. 13 cases). In group A 11/13, 85% had typical AC, with inverted T wave in > V1-V2 and left bundle branch block (LBBB) ventricular arrhythmias (VA), but echocardiography was performed only once; and only 2 cases had left ventricular variant, not reaching the AC diagnostic criteria. All 13 cases of group B had left ventricular or biventricular variant of AC, with inverted T wave in V5-V6 (7/13, 54%), low QRS complex in 4 (4/13, 31%), LBBB or right bundle branch block VA (7/13, 54%). Echocardiography did not show morpho-functional abnormalities, while cardiac magnetic resonance (CMR) was performed only once with left ventricular late enhancement. At postmortem, all these AC cases demonstrated a subepicardial-midmural fibrofatty replacement of the left ventricular free wall, without thinning/aneurysm or dilatation.

Conclusions:
AC still represents a major cause of SD in athletes in Italy since the left ventricular or biventricular variant without aneurysms escape routine echocardiographic detection. Athletes with inverted T waves in lateral leads and/or low QRS voltage as well as unexplained VA and normal echocardiography require further examination including CMR before allowing sport participation.
Abstract 207: The Prevalence and Significance of Abnormal Vital Signs Prior to In-Hospital Cardiac Arrest
Authors: Kim Won Young , Andersen Lars W , Mortensen Sharri , Chase Maureen , Berg Katherine , Cocchi Michael N , Donino Michael
Published: July 2021

Background:
The association between vital sign abnormalities prior to cardiac arrest and outcome has not been previously reported. In this study we investigated the prevalence of abnormal vital signs prior to in-hospital cardiac arrest and the association with mortality

Methods:
We utilized the Get With the Guidelines - Resuscitation national registry to identify adult patients with an in-hospital cardiac arrest between 2007-2010. We included index events and excluded patients with missing data on vital signs within 1-4 hours prior to arrest. We evaluated the prevalence of abnormal vital signs classified as mild, moderate or severe (Table 1). We determined the association between the number of abnormal vital signs per patient and in-hospital mortality using multivariate logistic regression with adjustment for multiple potential confounders including patient demographics and co-morbid conditions.

Results:
A total of 9,560 patients were included. Median age was 71 (60 - 81) years, 42% were female and overall mortality was 77%. The prevalence of vital sign abnormalities is shown in Table 1. As illustrated in Figure 1 we found a step-wise increase in mortality with increasing number of abnormal vital signs that remained in multivariable analysis across all categories (Mild: adjusted OR 1.37 [CI: 1.27 - 1.48], Moderate: adjusted OR 1.53 [CI: 1.35 - 1.73] and Severe: adjusted OR 1.43 [CI: 1.21 - 1.70], all p-values < 0.0001).

Conclusion:
Abnormal vital signs are common within four hours before cardiac arrest on in-hospital wards. Our study demonstrates incremental increases in mortality with both increasing number of pre-arrest abnormal vital signs as well as increased severity.
Abstract 219: Out-of-Hospital Cardiac Arrest in Vienna 2014
Authors: Keferböck Markus , Datler Philip , Krammel Mario , Lobmeyer Elisabeth , Nürnberger Alexander , Poppe Michael , Sulzgruber Patrick , Van Tulder Raphael , Zeiner Sebastian , Sterz Fritz
Published: July 2021

Background:
Sudden cardiac arrest (SCA) and especially the out of hospital cardiac arrest (OHCA) is always an urgent situation, which requires well trained medical personnel. The emergency medical system (EMS) in Vienna took part in the Circulation Improving Care (CIRC) trial form 2008 to 2010. In this time they had an additional training. Therefore we revaluated the outcome of OHCA nowadays.

Method:
Interim report of a prospective observational study of all humans over eighteen, who suffer an OHCA resuscitated by the EMS in Vienna from August 2013 - April 2014. For those patients, who survived 30 days, a cerebral performance category score (CPC) was evaluated.

Results:
During nine months 701 patients could be investigated and 625 achieved the protocol for this trial. The median age of the patients was 68 years (IQR 59-79) and 399 (64%) were male. Witnessed by bystanders was the cardiac arrest in 359 (57%) patients. In the latter patients restoration of spontaneous circulation (n=223, 36%)(ROSC) and 30 day survival (n=166, 27%) was significantly more often achieved than in patients with non-witnessed cardiac arrest. Bystanders provided chest compressions in 284 (45%) cases and in this subgroup a shockable initial rhythm was more often (p<0.0001). Still in 189 (53%) of the patients where the cardiac arrest was witnessed, bystander resuscitation wasn′t attempted. An initial shockable rhythm was found in 146 (24%) patients with significant better outcome in all primary outcome measures. Of the 62 (10%) 30-days-survivors, 33 (6%) had good neurological outcome with a CPC 1-2.In 12 (2%) cases the CPC was missing.

Conclusion:
The results are comparable to findings of our previous studies. A significant better result in all primary outcome measures could be found for witnessed OHCA with an initial shockable rhythm. Furthermore those patients with bystander CPR had significant more often a shockable initial rhythm. Therefore more efforts have to be invested into encouraging the community to start with a bystander CPR if an OHCA is witnessed.
Abstract 223: PBEF/Nampt Protects Against Mouse Sudden Cardiac Arrest Injury
Authors: Li Jing , Wang Huashan , Qian Yuanyu , Lee Chun-pei , Zhu Xiangdong , Bunney Ryan , Chen Jiwang , Machado Roberto , Garcia Joe G N , Vanden Hoek Terry
Published: July 2021

Introduction:
Pre-B-cell colony-enhancing factor or nicotinamide phosphoribosyltransferase (PBEF/Nampt) is critical for NAD
+
biosynthesis and metabolism. Given the important role of early metabolic recovery to sudden cardiac arrest (SCA) survival, we hypothesized that PBEF/Nampt deficient mice would demonstrate worse SCA outcomes after cardiopulmonary resuscitation (CPR).

Methods:
C57BL6 wild type and PBEF/Nampt
+/-
mice underwent 8 min of KCl-induced SCA and were monitored for 4 h survival after CPR. Heart, brain and blood PBEF/Nampt concentrations were measured by Western blot and ELISA. Tissue NAD
+
concentrations and blood markers of metabolic recovery including plasma lactate, glucose and insulin were measured.

Results:
At baseline, heart and brain tissue levels of PBEF/Nampt were significantly decreased by 50% in PBEF/Nampt
+/-
mice with no change of NAD
+
concentrations. By 4 h after CPR PBEF/Nampt
+/-
mice had worse survival, with 83% dead of cardiovascular collapse (n=18) compared to 45% of WT mice (n=11) (
p
< 0.05). At 4 h after CPR, heart NAD
+
concentration were significantly decreased by more than 50% in PBEF/Nampt
+/-
mice versus WT mice (p < 0.05). Blood PBEF/Nampt was significantly increased in both WT and PBEF/Nampt
+/-
mice compared to sham controls, with PBEF/Nampt
+/-
mice demonstrating lower blood PBEF/Nampt concentrations and higher plasma glucose, insulin and lactate concentrations.

Conclusion:
PBEF/Nampt tissue deficiency decreases successful cardiovascular resuscitation within 4 h after SCA and CPR. Early survival after SCA is related to tissue NAD
+
concentrations in the heart and blood PBEF/Nampt concentrations by 4 h after CPR. The role of tissue PBEF/Nampt as a possible therapeutic target after SCA warrants further study.
Abstract 226: Sex Differences in Cardiac Catheterization Following Out-of-Hospital Cardiac Arrest
Authors: Mumma Bryn E , Holmes James F , Wilson Machelle D , Diercks Deborah B
Published: July 2021

Introduction:
Cardiac catheterization is recommended for patients resuscitated from out-of-hospital cardiac arrest (OHCA) with a suspected cardiac etiology. Women are less likely than men to receive cardiac catheterization in other presentations of cardiovascular disease, but it remains unknown whether this disparity extends to OHCA.

Objective:
To determine whether patient sex is associated with undergoing cardiac catheterization after OHCA.

Methods:
We included all adult cases in the 2011 California Office of Statewide Health Planning and Development (OSHPD) database with a present-on-admission diagnosis of cardiac arrest (ICD-9-CM 427.5) or sudden cardiac death (ICD-9-CM 798) who were admitted from the emergency department to an acute care hospital. Data extracted from the OSHPD database included patient demographics, diagnoses, and procedures. ICD-9-CM procedure codes from the OSHPD database were used to identify patients who received cardiac catheterization. To determine factors associated with undergoing cardiac catheterization, we used a hierarchical logistic regression model that included age, sex, race, ethnicity, insurance type, ventricular arrest rhythm, and treatment at a hospital with 24/7 percutaneous coronary intervention capability.

Results:
We studied 4493 men and 3287 women admitted following OHCA. Women were older (median age 70 vs 64 years; p<0.001), had had fewer ventricular arrest rhythms (21.8% vs 31.7%; p<0.001), and received fewer cardiac catheterization procedures [12.5% vs 21.4%; p<0.0001]. This sex difference in cardiac catheterization persisted in the multivariable hierarchical model (adjusted OR 0.65; 95% CI 0.57-0.76; p<0.0001) and in a subgroup analysis including only patients with ventricular arrest rhythms (adjusted OR 0.63; 95% CI 0.51-0.78; p<0.0001)

Conclusion:
Sex differences exist in cardiac catheterization following resuscitation from OHCA. Future efforts should focus on understanding and resolving these differences.
Abstract 262: Women Are Less Likely to Be Resuscitated than Men
Authors: Blom Marieke T , Berdowski Jocelyn , Bardai Abdennasser , Tan Hanno L
Published: July 2021

Background:
There is a gender disparity in utilization of and benefit from health care. In various fields of medicine, women underuse the health care system and seem to benefit less when accessing health care than men. We aimed to study whether access to and outcome after out-of-hospital cardiopulmonary resuscitation (CPR) differs between men and women.

Methods:
We performed a population-based cohort study of non-traumatic out-of-hospital cardiac arrest (OHCA) cases before EMS arrival between 2006 and 2012. By using death certificate data of the national statistics service, we identified all cardiac out-of hospital deaths in the same period. Persons aged <20 years were excluded. First, we calculated the Mantel-Haenzel odds ratio (OR-MH) for gender and chance of a resuscitation attempt, while weighing the number of persons per age-category. Second, neurologically intact survival (NI-survival) after resuscitation attempt was regressed on gender in the total group and stratified according to score on resuscitation parameter. Third, multivariable logistic regression was used to assess the independent association between gender and shockable initial rhythm.

Results:
We identified 22,443 OHCAs (52.8% male), and recorded 6,038 CPR attempts after OHCA of cardiac cause (72.5% male). Men have a significantly higher chance of receiving a resuscitation attempt than women (pooled OR-MH 1.63, 95%CI 1.52-1.75, p<0.001). Women benefited less from CPR than men; NI-survival was higher in men compared to women (20.4% vs. 13.0%, OR 1.71, 95%CI 1.46-2.01, p<0.001). The gender gap in survival was explained by a lower incidence of a shockable initial rhythm in women (48.8% vs. 34.4%). Gender was independently associated with presence of a shockable initial rhythm (OR 1.83, 95%CI 1.60-2.09, p<0;001); so were CPR parameters.

Conclusions:
Women are less likely than men to receive CPR by EMS in case of OHCA. When women do receive CPR, they have lower chance of survival. The survival disparity is gender related and can only partly be explained by CPR circumstances.
Abstract 264: The Association of Chest Compression Fraction and Clinical Outcomes from Shockable Out-of-Hospital Cardiac Arrest During the Resuscitation Outcomes Consortium Primed Trial
Authors: Cheskes Sheldon , Schmicker Robert H , Rea Tom , Powell Judy , Drennan Ian R , Kudenchuck Peter , Vaillancourt Christian , Conway William , Stiell Ian , Stubb Dion , Davis Dan , Alexander Noah , Christenson Jim ,   and the ROC Investigators
Published: July 2021

INTRODUCTION:
The role of chest compression fraction (CCF) in resuscitation of shockable out-of-hospital cardiac arrest (OHCA) is uncertain. We evaluated the relationship between CCF and clinical outcomes in a secondary analysis of the Resuscitation Outcomes Consortium (ROC) PRIMED trial.

METHODS:
We included OHCA patients from the ROC PRIMED trial who suffered cardiac arrest prior to EMS arrival, presented with a shockable rhythm, and had cardiopulmonary resuscitation (CPR) process data for at least one shock. We used multivariable logistic regression adjusting for Utstein variables, CPR metrics of compression rate and perishock pause, and ROC site to determine the relationship between CCF and survival to hospital discharge, return of spontaneous circulation (ROSC), and neurologically intact survival defined with Modified Rankin Score (MRS) ≤ 3. Due to potential confounding between CCF and cases that achieved early ROSC, we also performed an analysis restricted to patients without ROSC in the first 10 minutes of EMS resuscitation.

RESULTS:
Among the 2,558 eligible patients, median (IQR) age was 65 (54, 76) years, 76.9% were male, and mean (SD) CCF was 0.70 (0.15). Compared to the reference group (CCF < 0.60), the odds ratio (OR) for survival was 0.57 (95%CI: 0.42, 0.78) for CCF 0.60-0.79 and 0.32 (95%CI: 0.22, 0.48) for CCF ≥0.80. Results were similar for outcomes of ROSC and neurologically intact survival. Conversely, when restricted to the cohort who did not achieve ROSC during the first 10 minutes (n=1,660), the relationship between CCF and survival was no longer significant. Compared to the reference group (CCF < 0.60), the OR for survival was 0.85 (95 %CI: 0.58, 1.26) for CCF 0.60-0.79 and OR 0.87 (95%CI: 0.58, 1.36) for CCF ≥0.80.

CONCLUSIONS:
In this observational cohort study of OHCA patients presenting in a shockable rhythm, CCF when adjusted for Utstein predictors, CPR metrics and ROC site was paradoxically associated with lower odds of survival. The relationship between CCF and clinical outcomes was null in a sensitivity analysis restricted to patients without ROSC in the first 10 minutes. CCF is a complex measure and taken by itself may not be a consistent predictor of clinical outcome.
Abstract 271: Continuous Amplitude Spectral Area May Reflect Adequacy of Myocardial Perfusion Before Attempting Defibrillation
Authors: Gazmuri Raúl J , Kaufman Christopher L , Whitehouse Herbert K , Baetiong Alvin , Radhakrishnan Jeejabai
Published: July 2021

Background:
Previous studies have shown that analysis of the VF amplitude-spectral area (AMSA) contains information predictive of electrical shock success. However, the underlying factors that determine AMSA remain elusive. We developed an open-chest swine model of VF in which we modeled “average CPR” followed by “highly effective CPR” using extracorporeal circulation (ECC) and assessed AMSA in relation to adequacy of coronary perfusion.

Methods:
VF was electrically induced and left untreated for 8 min in 8 pigs after which ECC was started and maintained for 10 min adjusting the flow to generate a coronary perfusion pressure (CPP) of 10 mmHg (low-flow ECC). After delivery of an initial shock, the ECC flow was increased and titrated to secure a mean aortic pressure of 40 mmHg (high-flow ECC) delivering additional electrical shocks at 60 s intervals. Blood flow through the left anterior descending (LAD) artery was reported relative to baseline (LAD rel). AMSA was measured continuously with a 2.1 s timeframe and a Tukey window that moved ahead every 0.5 s, and was averaged every min for this report (Figure).

Results:
AMSA increased during the initial 5 min of low-flow ECC, but subsequently decreased (Figure). The initial shock uniformly failed to terminate VF prompting increases in ECC to high-flow, which then resulted in the return of spontaneous circulation in each instance after 3 to 5 shocks. During the high-flow ECC, AMSA initially increased but then gradually decreased for reasons that are not clear. Before attempting defibrillation, AMSA was positively correlated with LAD rel (r=0.73, p=0.04).

Conclusion:
The study provides intriguing data showing changes in AMSA that are time dependent and likely influenced by myocardial perfusion and the effects of electrical shocks on the myocardium. The present study also suggests that the level of AMSA prior to attempting defibrillation may be influenced by the efficacy with which the CPR intervention generates coronary blood flow.
Abstract 277: Supraglottic Airway Use Is Associated with Higher Chest Compression Fraction than Endotracheal Intubation During Out-of-Hospital Cardiopulmonary Arrest
Authors: Kurz Michael C , Prince David , Christenson J , Carlson J , May S , Stub D , Cheskes S , Lin S , Aziz Michael , Austin Michael , Vaillancourt C , Colvin J , Wang Henry E ,   for the ROC Investigators
Published: July 2021

Objective:
Chest compression interruptions - such as those from endotracheal intubation (ETI) - are associated with poorer out-of hospital cardiac arrest (OHCA) survival. Select Emergency Medical Services (EMS) practitioners substitute ETI with supraglottic airway (SGA) insertion to minimize these interruptions, but the resulting effects upon chest compression fraction (CCF) are unknown. We sought to determine the differences in CCF between adult OHCA receiving ETI and those receiving SGA.

Methods:
We studied adult, non-traumatic OHCA patients enrolled in the Resuscitation Outcomes Consortium (ROC) PRIMED trial. Chest compressions were measured using compression or thoracic impedance sensors. We limited the analysis to those receiving ETI or SGA and >2 minutes of chest compression data before and after airway insertion. We compared CCF between ETI and SGA before and after airway insertion, adjusting for age, sex, witnessed arrest, bystander CPR, shockable initial rhythm, public location, PRIMED trial arm, and regional ROC center. We also compared the change in CCF for each airway technique and stratified these analyses by initial rhythm. We analyzed the data using t-tests and multivariable linear regression.

Results:
Of 14,955 patients enrolled in the ROC PRIMED trial, we analyzed 2,767 cases, including 2051 ETI, 671 SGA, and 45 both. Unadjusted pre- and post- airway CCF was higher for SGA than ETI (pre- 0.732 vs 0.706, difference -0.026 95% CI -0.044, -0.008; post- 0.767 vs 0.724, difference -0.043 95% CI -0.060, -0.026). Adjusted post-airway CCF improved with both techniques, but the changes were not statistically significant (0.012 difference, 95% CI 0.036, -0.012, p-value 0.32). CCF differences were similar when stratified by initial rhythm.

Conclusion:
In this series SGA insertion was associated with a higher CCF than ETI and that difference persisted post-airway insertion. Advanced airway management strategy may minimally impact CCF.
Abstract 278: The Association of Gender and Age with the Quality of Layperson CPR Performance
Authors: Leary Marion , Buckler David , Agarwal Amit , Abella Benjamin S , Blewer Audrey L
Published: July 2021

Background:
Clinical investigations have suggested that gender is associated with the quality of CPR, particularly chest compression (CC) depth, when performed by healthcare providers. Other studies have shown that performing CC depth >50 mm may be difficult in clinical practice, and may depend on provider characteristics that impact strength. Few studies have examined the association of gender and age with layperson CPR.

Objective:
We sought to determine the association of gender and age on the quality of CPR performed by laypersons during simulated CPR performance. We hypothesize that female gender and increasing age may be associated with shallower CC depth.

Methods:
In a secondary analysis of a multicenter trial of CPR training for cardiac patient caregivers, CPR skills were assessed 6 months after training. We analyzed the association of subject age and gender with CC rate, depth and no-flow time. CPR metrics were captured using a CPR skill-recorder manikin. Each variable was analyzed independently, then via a multivariable regression model to adjust for confounders such as BMI.

Results:
Between 7/2012-4/2014, 401 laypersons completed a CPR assessment. Mean age was 51.5±14.0 years, 74% were female, and 50% had a high school diploma/GED. Overall, mean CC depth was 43.8±14.2 mm, mean rate was 87.9±14.2 per min, and mean no-flow time per min was 7.5±11.0 sec. Male subjects performed deeper CC than female subjects (48.2±1.2 v. 42.2±0.7, p<0.01). As age increased, both male and female CC depth decreased significantly (see Table 1a and 1b). When analyzed independently, and controlling for other variables, BMI was not associated with CC depth. Additionally, there was no association between gender or age with CC rate or no-flow time while controlling for other variables.

Conclusions:
We found that female gender is associated with shallower CC depth and this difference was not confounded by BMI. Additionally, as lay providers increased in age, their CC depth decreased.
Abstract 287: 5-Hydroxydecanoate, a Mitochondrial Selective KATP Antagonist, Blocks the Rescue Action of Lipid Emulsion in Bupivacaine-Induced Cardiotoxicity
Authors: Partownavid Parisa , Sharma Salil , Rahman Siamak , Eghbali Mansoureh
Published: July 2021

Introduction:
Lipid emulsion (intralipid) rescues Bupivacaine-induced cardiac toxicity. We have shown previously that glibenclamide, a non selective ATP potassium channel blocker abolishes the rescue action of intralipid. Here we explored the role of 5-Hydroxydecanoate (5-HD), a mitochondrial selective KATP antagonist in the intralipid-mediated rescue of bupivacaine overdose.

Methods:
Young male Sprague-Dawley rats (300-350 g) were anesthetized intraperitoneally with a mixture of ketamine (80 mg/kg) and xylazine (8 mg/kg), and ventilated with a ventilator. M-mode echocardiography were acquired throughout the experiment. In protocol-1 (n=5), asystole was induced by a single injection of bupivacaine (10mg/kg over 20 seconds, intravenously) and resuscitation with Intralipid 20% (5ml/kg bolus, and 0.5ml/kg/min maintenance) with chest compression was started immediately. In protocol-2 (n=8) rats were pre-treated with 5-HD (5 mg/kg, IV) 30 minutes prior to inducing asystole with bupivacaine. In both protocols the heart rate (HR), ejection fraction (EF) and fractional shortening (FS) were measured before inducing asystole (baseline), and at 1, 5 and 10 min after lipid treatment. A two way repeated measure analysis of variance (ANOVA) model was used for comparison of means. Values are mean ± SEM, n=5 rats/group, p<0.05 significant.

Results:
In protocol-1, the baseline HR and EF were 321±21 and 72.3±4.6%. Bupivacaine resulted in asystole and intralipid therapy improved the heart rate and cardiac function within 10 min(HR=86±13beats/min at 1min, 216±10beats/min at 5 min, and 228±14beats/min at 10 min). The left ventricular systolic function fully recovered in all rats within 5 min of intralipid treatment (EF=72±5%, FS=42±4%). In protocol-2, there were no significant differences between HR and EF before (HR=324.6±16.5 beats/min, EF=78.0±2.8%) and 30 min after (HR=340.9±15.6 beats/min, EF=83.3±2.0%) 5-HD adminstration. However, 5-HD (5mg/kg), prevented the intralipid-induced rescue of bupivacaine overdose, as there was no recovery within 10 min of intralipid therapy.

Conclusions:
Pre-treatment with 5-HD prevents the lipid rescue of bupivacaine-induced cardiotoxicity suggesting that mitochondrial KATP channels are involved.
Abstract 289: Effect of Elevated Legs on Hemodynamic Performance During Cardiopulmonary Resuscitation in a Porcine Model of Cardiac Arrest
Authors: Qvigstad Eric , Neset Andres , Olasveengen Theresa M , Tømte øystein , Eriksen Morten , Norseng Per Andreas , Sunde Kjetil , Kramer-Johansen Jo
Published: July 2021

Purpose of the study:
During advanced life support (ALS) end-tidal carbon dioxide (EtCO
2
) reflects cardiac output (CO). A recent clinical study found an association between passive leg raising (PLR) and increased EtCO
2
during ALS. This may reflect a transient increase in pulmonary blood flow and CO, but might cause a detrimental decrease in coronary perfusion pressure (CPP). We evaluated the effect of PLR during experimental ALS in a randomized, factorial design.

Materials and methods:
In nine anesthetized domestic pigs (30±1.8 kg) ventricular fibrillation was induced electrically. After 3 minutes of no-flow, mechanical chest compressions (5cm @ 100 min
-1
) were started. During four 5-minute segments of CPR we measured CO, EtCO
2
, perfusion pressures, carotid and cerebral cortical microcirculatory blood flow (MBF) and CPP (the average of the positive pressure difference between decompression aortic pressure (AP) and right atrial pressure (RAP)) at minute 2 and 4. Interventions were provided in a randomized sequence with PLR vs supine position, with or without epinephrine (0.5mg iv). Values are given as mean±standard deviation.

Results:
PLR did not increase EtCO2 compared to supine position (3.1±0.7 vs 3.0±0.8 kPa), but CO was minimally increased from 1.1±0.3 to 1.2±0.3 Lmin
-1
,(p=0.003). PLR did not significantly increase AP

(57±15 vs. 48±18 mmHg, p=0.3), but RAP was higher (43±10 vs. 31±7, p=0.003). However, no difference was found in CPP due to marked variation in both groups (median(range): PLR 20 (9,43) and supine 17(9,58)). The effect of epinephrine during this experimental setup was minimal.

Conclusion:
We did not find a positive effect of PLR during experimental ALS, but there were no obviously detrimental effects either.
Abstract 306: Similar Hemodynamic Efficacy Between 30 mm and 50 mm Compression Depth During Mechanical Chest Compression with Weil Mini Chest Compressor
Authors: Yang Zhengfei , Gong Ping , Wu Xiaobo , Qian Jie , Zhao Shen , Duggal Neil , Tang Wanchun
Published: July 2021

Introduction:
Current guidelines require a 50 mm compression depth for manual chest compression. During mechanical chest compression, however, because of the design of each device, whether this depth yields the most optimal hemodynamic efficacy remains to be tested. In this study, we investigated the effects of compression depth on hemodynamics efficacy during mechanical CPR with the Weil Mini Chest Compressor in a porcine model.

Hypothesis:
There is no significant difference in hemodynamic efficacy between compression depth of 30 mm and 50 mm during mechanical CPR with the Weil Mini Chest Compressor.

Methods:
Ten male domestic pigs weighing 34±2 kg were utilized. Ventricular fibrillation was electrically induced and untreated for 7 min. The animals were then randomized to receive compression depth of 30 mm or 50 mm. Coincident with the start of precordial compression, the animals were mechanically ventilated at a rate of 10 breaths per minute. Defibrillation was attempted by a single 150 J shock. If resuscitation was not successful, CPR was resumed for 2 mins prior to the next defibrillation until either successful resuscitation or for a total of 15 mins.

Results:
All animals were successfully resuscitated. There were no differences in coronary perfusion pressure (CPP), end-tidal carbon dioxide (ETCO2) and carotid blood flow (CBF) between the two groups (Table). A significantly less rib fracture was observed in the 30 mm group [0 (0-0) vs 1.2 (0-2), p<0.05].

Conclusion:
Similar hemodynamic efficacy was observed between 30 and 50 mm compression depth during mechanical CPR with the Weil Mini Chest Compressor.