bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 256: Therapeutic Hypothermia Decreases Arrhythmia Substrates by Attenuating Repolarization Current
I
K,ATP
During Myocardial Ischemia
Authors: Piktel Joseph S , Rosenbaum David S , Wilson Lance D
Published: April 2024

Background:
While hypothermia is arrhythmogenic, the effect of therapeutic hypothermia (TH) performed after cardiac arrest on susceptibility to arrhythmias is not well understood. Clinically, patients do not have an increase in arrhythmias, and it is possible that TH may be cardioprotective. The repolarization current
I
K,ATP
is activated only during ischemia where it heterogeneously shortens action potentials increasing dispersion of repolarization (DOR). Since
I
K,ATP
is attenuated at cooler temperatures, we hypothesized that the antiarrhythmic effect of TH during ischemia may be mediated by attenuation of
I
K,ATP
activation. To test this hypothesis, a model of no flow global ischemia in the canine wedge preparation was created to study the effects of ischemia on all cell types spanning the transmural wall.

Methods:
Optical action potentials were recorded transmurally with high spatial (1 mm), temporal (.5 ms) and voltage (.5mv) resolution. To block
I
K,ATP,
glibenclamide (10 µmol) was used at both 36
o
C (normal temperature, NT+
I
K,ATP
block, n=3) and 32
o
C (TH+
I
K,ATP
block, n=3) during 15 min of no flow global ischemia.
I
K,ATP
blockade was compared to prior controls (NT=7, TH=6). Action potential duration (APD) for epicardial, mid-myocardial, and epicardial cells, DOR, and conduction velocity (CV) were measured for all conditions.

Results:
There was no difference in DOR between the 4 groups prior to ischemia. NT+
I
K,ATP
block attenuated ischemia-induced increase in DOR compared to NT controls (22±4 ms to 25±5 ms vs. 30±5 to 57±5 ms, p=.002). NT+
I
K,ATP
block also attenuated ischemia-induced conduction slowing (44±2 to 30±3 cm/s vs 34±5 to 18±3 cm/s, p=.03). Addition of
I
K,ATP
block to TH did not further attenuate the DOR or CV vs. TH alone (p>0.05). Ischemia-induced epicardial conduction bock was attenuated by
I
K,ATP
blockade, (0/3
I
K,ATP
block vs. 6/7 NT) Epicardial block was attenuated in both TH groups.

Conclusions:
I
K,ATP
blockade attenuates ischemia-induced DOR, conduction slowing, and epicardial conduction block, reproducing the effect of TH. This suggests that hypothermia-induced attenuation of
I
K,ATP
may play a role in the mechanism of attenuation of ischemia-induced arrhythmias observed in TH.
Abstract 262: Slight Therapeutic Hypothermia (35°C to 36°C) for Post--Cardiac Arrest Syndrome Due to Ventricular Fibrillation with Low Left Cardiac Function Is a Feasible and Safe Possibility
Authors: Orita Tomohiko , Sasao Kenichirou , Toyoda Yukitoshi , Mukai Koichi , Kitano Mitsuhide ,   Dept of Emergency and Critical Care Medicine, Ito Yoshiaki , Ishimori Hiroshi , Hirano Keisuke , Nakano Masatsugu , Yamawaki Masahiro , Araki Motoharu , Kato Tamon , Takimura Hideyuki , Sakamoto Yasunari , Komatsu Ikki , Takama Takurou , Nunoya Kanai , Tsukahara Reiko , Muramatsu Toshiya ,   Dept of Cardiology
Published: April 2024

Background:
Mild therapeutic hypothermia (32-34°C, 24-48 hours: mild TH) for post cardiac arrest syndrome (PCAS) due to ventricular fibrillation (VF) had been recommended in the American Heart Association (AHA) Guidelines 2005 (class IIa) and the International Liaison Committee on Resuscitation (ILCOR). In the AHA guidelines 2010, it has been recommended more strongly (class I). But it is still unknown what temperature is best for low cardiac function patients including acute myocardial infarction (AMI) cases. Sometimes executing mild TH for patients with severe left ventricular dysfunction are not so easy and safe because of hypotension, arrhythmias, unstable vital signs and so on. So we studied whether slight therapeutic hypothermia (35-36°C: Slight TH) was effective and safe compare with mild TH for PCAS due to VF.

Methods:
Consecutive PCAS patients who were witnessed, done by-stander cardiopulmonary resuscitation (CPR), confirmed VF caused by cardiac or coronary events and introduced therapeutic hypothermia for the latest 45 months were sorted into the GroupM (Mild TH, 34°C, 24-72 hours) and the GroupS (Slight TH, 35-36°C, 24-72 hours).The primary end point was a favorable neurologic outcome (cerebral performance category: CPC 1 or 2) in 28th days after cardiac arrest. Secondary end points were the changes of cardiac index (CI) after introducing therapeutic hypothermia, the time required to reach target temperature and the rate of complications (infections, bleeding, arrhythmias etc.) within fourteen days.

Results:
Thirty-five patients (twenty AMI cases) were studied (GroupM 20 patients and GroupS 15 patients). The rate of favorable neurologic outcome was available and did not differ significantly between the two groups (50% vs. 53%, p=0.85). The time to reach target temperature was significantly shorter in the GroupS (5.9h vs. 0.9h, p<0.01). The decrease of CI was remarkable in the groupM (before TH/during TH, GroupM 2.8/2.2, GroupS 1.9/2.1, the changes of them were Δ32% vs. +0.05%, p<0.01). The rate of complications did not differ significantly between them and there were no major complications.

Conclusion:
Slight therapeutic hypothermia for PCAS due to VF with low cardiac function is possibility feasible and safe.
Abstract 274: Filter Out the Chest Compression Signal Interference During Ventricular Fibrillation by Signal Processing
Authors: Huang Chien-Hua , Lin Lian-Yu , Hsu Chiung-Yuan , Tsai Min-Shan , Ma Mattew Huei-Min , Chen Wen-Jone
Published: April 2024

Background:
Ventricular fibrillation (VF) is the major cause of sudden cardiac death. The most effective way to stop VF is to defibrillate. However, current automated external defibrillator does not allow chest compression when doing electrogram analysis. Many studies have shown that the mortality rate of VF increased rapidly when the “hands-off” intervals lengthen. The goal of the present project is to develop a new method to filter the chest compression signals in ECG and to reduce the “hands-off” time.

Methods:
We induced VF in rat and the precordial compression was performed with a pneumatically driven mechanical chest compressor at different frequency (150cpm, 200cpm, 300cpm) for 30 seconds after 30 seconds of VF. The ECG signals were processed with empirical mode decomposition and comb filter to filter out the chest compression signals. We then calculated the spectrogram to prove the effect of the filter and the amplitude spectrum analysis (AMSA) to demonstrate the time evolution of VF during and after chest compression.

Results:
A total of 6 rats in each group were studied. From the spectrogram, we found that the chest compression signals were effectively removed after signal processing. Moreover, the AMSA significantly increased in VF group with chest compression at rate 150cpm. When stopping chest compression, the AMSA rapidly decreased in all groups.

Conclusions:
The chest compressions signals in ECG can be effectively filtered out from VF by the combination of EMD and comb filter.
Abstract 284: Real Time Blood Pressure Dynamics During Fluid Resuscitation Predict 6-Hour Survival in a Swine Model of Polytrauma with Uncontrolled Hemorrhage
Authors: White Nathan J , Wang Xu , Bradbury Nicole , Stern Susan
Published: April 2024

Objective:
Blood pressure responses to fluid resuscitation during trauma can reflect blood loss and shock severity. We examine early blood pressure responses to fluid resuscitation to test the hypothesis that rapid blood pressure dynamics during trauma resuscitation may also predict longer-term survival.

Methods:
Mean arterial pressure (MAP) during the initial fluid resuscitation was abstracted from a study using an anesthetized swine model of traumatic brain injury and catheter/free hemorrhage by aortic tear. Animals were hemorrhaged to MAP=30mmHg for 15 minutes prior to resuscitation. Lactated Ringers (LR, 20ml/kg) or a Hemoglobin-based Oxygen Carrier (HBOC, 10ml/kg) was then given over 10 minutes and repeated every 15 minutes thereafter for MAP < 60mmHg for up to 105 minutes. The aortic tear was then repaired and the animal further resuscitated using Normal Saline and shed blood to predefined criteria for up to 6 hours. Serial invasive MAP measurements recorded in 5 minute intervals over the first 15 minutes of fluid infusion were correlated with blood loss and survival time. MAP dynamics as predictors of 6 hour survivorship were examined by nominal logistic regression.

Results:
50% of animals (7/14) survived to 6 hours. There were no differences in initial MAP responses between LR and HBOC groups (p=0.85). Survivors demonstrated a more rapid and prolonged positive blood pressure response to the initial fluid bolus by a higher MAP at 5 minutes of fluid infusion (43.1 mmHg vs. 34.7 mmHg in nonsurvivors, T-test, p value=0.04) and a faster rate of increase (survivors = 3.0 mmHg/min vs. nonsurvivors= 1.4mmHg/min, Wilcoxon p value= 0.0008). MAP was sustained in survivors after the initial fluid infusion ended, but immediately declined in nonsurvivors. MAP increase was associated with total survival time (R=0.77, p=0.0012). A MAP rate of increase of at least 2.2mmHg/min over the first 5 minutes of fluid resuscitation predicted survival to 6 hours with 100% sensitivity and 75% specificity (AUC= 0.93, p< 0.0001). There was no association between blood pressure response and intraperitoneal hemorrhage volume.

Conclusion:
In this swine model, very early resuscitation MAP dynamics predicted longer-term survival and may reflect retained physiological reserve.
Abstract 287: Erythropoietin Enables Mitochondria to Preserve Oxidative Phosphorylation Under Conditions of Calcium Overload and Oxidative Stress
Authors: Radhakrishnan Jeejabai , Ng Matthew , Edelheit Ari , Gazmuri Raúl J
Published: April 2024

Introduction:
We previously reported in rats that a single bolus dose of erythropoietin (Epo) given at the start of CPR enhanced, within minutes, the efficacy of chest compression. The effect was attributed to attenuation of reductions in left ventricular distensibility; an effect previously linked to preservation of mitochondrial bioenergetic function.

Hypothesis:
We now investigated whether Epo could enable mitochondria to maintain oxidative phosphorylation under conditions of calcium overload and oxidative stress, which are central to injury caused by ischemia and reperfusion.

Methods:
Mitochondria were isolated from the left ventricle of hearts harvested from groups of rats (n=3) that received during spontaneous circulation no Epo or received Epo (5,000 U/kg) in bolus dose into the right atrium at 60, 240, and 480 seconds before harvest. Separate aliquots of mitochondria were subjected to incremental concentrations of calcium (1.5, 12.5, and 25 µM free calcium) or tert-butyl hydroperoxide (250 and 5000 µM). Phosphate:oxygen (P:O) ratios were then measured in a respiration chamber (MT 200, Mitocell, Strathkelvin Instruments).

Results:
Epo, in a time dependent manner, prevented reductions in P:O ratios observed when mitochondria were exposed to incremental concentrations of calcium or tert-butyl hydroperoxide (Table).

Conclusions:
Preservation of left ventricular myocardial distensibility could partly result from a favorable effect of Epo enabling mitochondria to resist injury caused by calcium overload and oxidative stress, and within a response time sufficiently rapid to favorably impact cardiac resuscitation.
Abstract 289: The Relationship of Chest Compression Rate and Survival During Out-of-Hospital Cardiopulmonary Resuscitation at Resuscitation Outcomes Consortium (ROC) Regional Sites
Authors: Idris Ahamed H , Guffey Danielle , Pepe Paul P , Daya Mohamud , Davis Dan , Stiell Ian G , Menegazzi James , Callaway Clifton , Christenson James , Gray Randal , Boyce Douglas , Lin Steve , Sheehan Kellie , Aufderheide Tom ,   Resuscitation Outcomes Consortium Investigators
Published: April 2024

Background:
Current American Heart Association guidelines for cardiopulmonary resuscitation (CPR) recommend a chest compression rate of at least 100 compressions/min. Animal and human CPR studies have reported improved blood flow associated with chest compressions rates ≥ 120/min, but few have reported rates used during out-of-hospital (OOH) CPR, or the relationship between rate and outcome.

Objective:
To describe chest compression rates used by emergency medical services (EMS) providers to resuscitate patients with OOH cardiac arrest and to determine the relationship between rate and outcome.

Methods:
Included were patients ≥ 20 years old enrolled in the ROC PRIMED study with OOH cardiac arrest treated by EMS providers. Data were abstracted from monitor-defibrillator recordings during the first 5 minutes of CPR. Multiple logistic regression assessed the association between chest compression rate and outcome. The model adjusted for sex, age, bystander and EMS witnessed arrest, attempted bystander CPR, public location, and ROC site.

Results:
10,330 patients had OOH CPR from June 2007 to November 2009. Mean age was 67 ± 16. Mean chest compression rate was 111 ± 19 (3 - 210) compressions/min during the first 5 minutes of CPR. Return of spontaneous circulation occurred in 34% and 9% survived to hospital discharge. Compared with the reference rate (100-120/min) (mean 109 ± 6), the adjusted odds ratios (OR) for survival were: compression rate from 0 - 80/min (mean 68 ± 13) OR 1.18 (CI 0.78 - 1.77), 80 - 100/min (mean 93 ± 5) OR 0.88 (0.73 - 1.06), 120 - 140/min (mean 128 ± 5) OR 0.88 (CI 0.73 - 1.08), >140/min (mean 151 ± 11) OR 0.77 (CI 0.54 - 1.11). A cubic spline curve suggests survival peaks at about 120/min and then declines at rates >120/min.

Conclusion:
Chest compression rates faster than 100/min were common. The study suggests that the likelihood of survival from OOH cardiac arrest is decreased with compression rates >120/min.
Abstract 17733: PPARdelta Activation Protects Endothelial Function In Diabetic Mice via PI3K/Akt/eNOS Signaling Pathway
Authors: Wong Wing Tak , Tian Xiao Yu , Huang Yu
Published: April 2024

Wing Tak Wong, 2011 Finalist and Presenting Author
Abstract 11784: Reduced BMPR2 Increases GM-CSF mRNA Translation by Inhibiting eIF2α Mediated Stress Granule Formation and Propensity to Pulmonary Vascular Disease
Authors: Sawada Hirofumi , Alastalo Tero-Pekka , Glotzbach Jason P , Chan Roshelle , Fuchs Gabriele , Januszyk Michael , Lai Ying-Ju , de Jesus Perez Vinicio , Saito Toshie , Spiekerkoetter Edda , Wang Lingli , Gurtner Geoffrey C , Sarnow Peter , Rabinovitch Marlene
Published: April 2024

Hirofumi Sawada, 2011 Finalist and Presenting Author
Abstract 51: Demographics, Automated External Defibrillator Deployment and Neurologically Intact Survival of Out-of-Hospital Pediatric Cardiac Arrest in the Cardiac Arrest Registry to Enhance Survival Registry
Authors: Johnson Austin , Sasson Comilla , Slattery David E , Loptien Matthew , McNally Bryan ,   CARES Surveillance Group
Published: April 2024

Background:
Since 2005, the American Heart Association has recommended that children in cardiopulmonary arrest (CA), greater than 1 year of age, receive an attempt at automated external defibrillator (AED) application and shock. However, little is known about whether these guidelines have reached the bystander response in the U.S.

Objective:
1) To characterize survival and neurologically intact (NI) outcomes of pediatric out of hospital CA events 2) To determine the prevalence of bystander cardiopulmonary resuscitation (CPR) and AED, particularly in those victims under 8 years of age.

Methods:
We conducted a secondary analysis of prospectively collected data from 29 U.S. cities that participate in the Cardiac Arrest Registry to Enhance Survival (CARES). Patients were included if they were less than 18 years of age and had a documented resuscitation attempt from October 1, 2005 through December 31, 2009. Chi-squared tests were used to test for differences in AED and bystander CPR provision between age groups.

Results:
A total of 481 cases comprised our cohort. The overall survival was 5.6 % (95% CI: 3.7-8.1), and NI survival was 3.5% (95% CI: 2.0- 5.6). Across all age strata, asystole was the most common initial rhythm. Sixty-six (13.7 % (95% CI: 10.8-17.1) patients had a shockable rhythm with increasing percentages of shockable rhythms at older ages (<30 days: 3.2% (n=2); 30 days-1 year old: 3.4% (n=7); 1-5 years old: 10.1% (n=7); 5-12 years old: 22.1% (n=13); 12-18 years old: 31.8% (n=27), p<0.05). Bystander CPR and AED rates are shown in the table. Overall AED use for the sample was 70/481; 14.6% (95% CI: 11.5-18.0) while the provision of bystander CPR was 160/481; 33.3% (95% CI: 29.1-37.7).

Conclusions:
Despite a similar rate of bystander CPR and higher rate of AED use, pediatric CA have lower overall and NI survival as compared to the adult population. Future research will need to be conducted to determine the barriers to children receiving bystander CPR and having AEDs applied
Abstract 10132: Integration of microRNA Expression Profiling and a Validated Gene Signature from Peripheral Blood Mononuclear Cells in Pulmonary Hypertension Associated with Sickle Cell Disease
Authors: Desai Ankit A , Zhou Tong , Ahmad Homaa , Trevino Sharon , Wade Michael , Thiruvoipati Tejas , Turner Kristin , Artz Nicole , Patel Amit R , Lang Roberto M , Garcia Joe G , Machado Roberto F
Published: April 2024

Ankit A Desai, 2011 Finalist and Presenting Author
Abstract 13101: Mst1-mediated Phosphorylation of Beclin1 in its BH3 Domain Promotes Beclin1-Bcl-2 Interaction, Thereby Negatively Regulating Autophagy in the Heart
Authors: Maejima Yasuhiro , Kyoi Shiori , Zhai Peiyong , Liu Tong , Li Hong , Sadoshima Junichi
Published: April 2024

Yasuhiro Maejima, 2011 Finalist and Presenting Author
Abstract 14174: MRI-Based Patient-Specific Virtual Electrophysiology Laboratory for Scar-Related Ventricular Tachycardia
Authors: Ashikaga Hiroshi , Arevalo Hermenegild , Vadakkumpadan Fijoy , Blake Robert C , Berger Ronald D , Calkins Hugh , Trayanova Natalia A , Halperin Henry R
Published: April 2024

Hiroshi Ashikaga, 2011 Finalist and Presenting Author
Abstract 16496: Circulating Systemic Factors from Young Mice Reverse Age-Related Cardiac Hypertrophy
Authors: Loffredo Francesco S , Steinhauser Matthew L , Tian Jack , Gannon Joseph , Shadrach Jennifer , Miller Christine , Pizzimenti Christie L , Wagers Amy J , Lee Richard T
Published: April 2024

Francesco S Loffredo, 2011 Finalist and Presenting Author
Even Cowboys Work in Teams
Authors: Summers Debbie
Published: April 2024

The title and inspiration for this presentation are taken from an address by Dr. Atul Gawande at the Harvard Medical School Graduation, 2011. Dr. Gawande stated, “The core structure of medicine emerged in an era when doctors could hold all the key information patients needed in their heads and manage everything required themselves. One needed only an ethic of hard work, a prescription pad, a secretary, and a hospital willing to serve as one's workshop…………But you can't hold all the information in your head any longer, and you can't master all the skills.” He goes on to say that in our current healthcare environment, “places that function most like a system (diverse people working together to direct their specialized capabilities toward common goals for patients) are most successful.” That defines a high functioning team or group of teams. Underpinning the success of a team are three skills described by Dr. Gawande: use of data to understand performance, self reflection and finding solutions to system problems based on data, and implementing the systems and team approach at scale. Optimal stroke care requires a diverse group of people working together as a highly functional team or group of teams. This presentation will discuss both the system and teams that have organized in the region around Kansas City to assure the best possible outcome for each stroke patient by getting as many patients as possible to the right place at the right time.
Abstract 64: Ability of Bystanders to Appropriately Provide Rescue Breathing in the Setting of a Chest Compression--Only CPR Campaign for Sudden Cardiac Arrest
Authors: Panchal Ashish R , Vadeboncoeur Tyler F , Stolz Uwe , Spaite Daniel W , Berg Robert A , Sanders Arthur B , Kern Karl B , Welch Alyson , Bobrow Bentley J , Ewy Gordon A ,   SHARE Study Group
Published: April 2024

BACKGROUND:
For sudden collapse from out-of-hospital cardiac arrest (OHCA) in adults, bystander chest compression-only CPR (COCPR) results in equivalent or better survival compared with conventional CPR with rescue breathing. However, patients who arrest from a non-cardiac cause may also receive COCPR even though rescue breathing might benefit them. We sought to determine whether lay rescuers appropriately provided COCPR or conventional CPR depending on the suspected etiology of OHCA.

METHODS:
Analysis of a statewide, Utstein-style registry of adult OHCA during a large-scale campaign endorsing COCPR for adults who suddenly collapse. The relationship between bystander CPR (both COCPR and conventional CPR), presumed arrest etiology, and survival to hospital discharge were evaluated. Means and 95% confidence intervals (CI) were calculated.

FINDINGS:
A total of 7,652 adult OHCAs not witnessed by EMS were analyzed from 10/04 to 09/10. After exclusion of non-lay bystanders and arrests in medical facilities, presumed cardiac etiology and non-cardiac etiology OHCA totaled 4,913 and 1,202, respectively. The presumed specific non-cardiac etiologies were non-cardiopulmonary (e.g. overdose, suicide, subarachnoid hemorrhage) (57%), trauma (27%), and respiratory (16%). All-rhythm survival was 7.0% (CI: 6.3 - 7.8) for cardiac etiologies and 3.3% (CI: 2.3 - 4.3) for non-cardiac (p<0.001). Bystander CPR was provided for 33% (CI: 31.4 - 34.1) of victims with presumed cardiac causes versus 28% (CI: 25.6 - 30.7) for non-cardiac causes (p=0.002). Presumed respiratory causes of OHCA had a much lower proportion of COCPR (8.3%, CI: 4.4 - 12.2) than cardiac causes (18.0%, CI: 16.9 - 19.1, p<0.001). Survival for
non-cardiac
cases was: 4.4% (CI 0.9 - 7.8) for conventional CPR, 3.5% (CI: 0.9 - 6.0) for COCPR, and 3.1% (CI: 2.0 - 4.3) for no CPR (p = 0.66).

CONCLUSIONS:
In the setting of a large-scale, statewide public health campaign endorsing lay rescuer COCPR for adults who suddenly collapse and are not breathing normally, bystanders were much less likely to perform COCPR on OHCA victims who might benefit from rescue breathing. Furthermore, when COCPR was performed on presumed non-cardiac cause arrest victims, there was no demonstrable negative impact on survival.
Abstract 8093: Inorganic Nitrite Induces Second-Window Preconditioning in Healthy Volunteers
Authors: Ormerod Julian O , Evans Jonathan D , Contractor Hussain , Kharbanda Raj , Frenneaux Michael P , Ashrafian Houman
Published: April 2024

Background
Inorganic nitrite has been shown to induce preconditioning in a variety of animal and tissue models. Work from our group has shown that nitrite can induce periconditioning in a human model of ischemia-reperfusion injury, which is influenced by ALDH2 genotype. We investigated whether systemic inorganic nitrite infusion, given 24 hours before the onset of ischemia, protects human forearm endothelium from ischemia-reperfusion injury in unselected healthy volunteers.

Methods
12 healthy volunteers were randomised to 2 groups. Inorganic nitrite or saline placebo was given intravenously at a dose of 1 mcg/kg/min for 10 minutes, 24 hours before the onset of studies. Venous occlusion plethysmography, using escalating doses of intra-arterial acetylcholine, was used to measure forearm endothelial function before and 15 minutes after 20 minutes of total forearm ischemia.

Results
Ischemia-reperfusion injury caused significant endothelial dysfunction in those that had received a placebo infusion (n=5, p<0.05). Conversely, the group that received systemic nitrite 24 hours before study were protected from IR injury (p=0.78 for a difference pre- and post-ischemia).

Discussion
This study shows, for the first time in man, that a simple cost-effective intervention has potential to prevent injury in situations where significant ischemia-reperfusion injury is predictable, such as in cardiac surgery. More speculatively, this mechanism may be involved in the health benefits of a diet containing nitrite-rich green leafy vegetables. This result invites further study in the form of clinical trials.
Abstract 8143: Prevalence of Iron Deficiency Screening in Patients with Acute Myocardial Infarction Who Develop Hospital-Acquired Anemia
Authors: Salisbury Adam C , Amin Amit P , Reid Kimberly J , Masoudi Frederick A , Wang Tracy Y , Alexander Karen P , Spertus John A , Kosiborod Mikhail
Published: April 2024

Background:
Hospital-acquired anemia (HAA), a new onset anemia in patients with normal admission hemoglobin (Hgb), is common, frequently develops in the absence of overt bleeding, and is associated with poor outcomes in acute myocardial infarction (AMI) patients. Iron deficiency may be an underlying modifiable risk factor for HAA, but the prevalence of iron deficiency screening and the frequency of iron deficiency is unknown in AMI patients.

Methods:
We studied 17676 AMI patients from 57 US hospitals in the Health Facts database who were not anemic at admission. HAA was defined as a nadir Hgb below age, gender and race specific thresholds and moderate-severe HAA was defined as nadir Hgb < 11 g/dl. All laboratory tests obtained and all in-hospital medications were recorded from the electronic medical record. We identified the proportion with and without HAA who had any laboratory evaluation of iron stores (ferritin, serum iron or iron binding capacity), and the frequency of iron deficiency among those who were tested (using established thresholds for patients with comorbid heart failure and kidney disease of a ferritin < 100 ng/ml or between 100 and 299 when transferrin saturation was <20% and a ferritin of < 45 ng/ml for all other patients).

Results:
Both mild (n=6615, 37%) and moderate-severe HAA (n=3551, 20%) were common. Assessment of iron stores was rare in all groups, but increased with greater HAA severity (no HAA: 52 (0.7%), mild HAA: 117 (2%) and moderate-severe HAA: 364 (10%), p<0.001). Among patients who had iron testing, iron deficiency was common regardless of HAA status (no HAA: 14/52 (27%), mild HAA: 24/117 (21%) and moderate-severe HAA (106/364 (29%), p=0.24). Few iron deficient patients received in-hospital iron supplementation (no HAA: 0/14, mild HAA: 2/24 (8%) and moderate-severe HAA: 16/106 (15%), p=0.25).

Conclusions:
Testing for iron deficiency is rare in AMI patients and is only slightly more common in those who develop HAA. Although only a select fraction of patients were screened, iron deficiency was common in these patients, and was infrequently treated. Studies are needed to determine the prevalence of iron deficiency in AMI patients with HAA and whether diagnosing and treating iron deficiency in AMI patients with HAA improves outcomes.
Abstract 8252: Altered Metabolism of Post-Prandial Remnant Lipoprotein Fractions in Autosomal Recessive Hypercholesterolemia
Authors: Tada Hayato , Kawashiri Masa-aki , Nakano Takamitsu , Nakajima Katsuyuki , Tsubokawa Toshinari , Konno Tetsuo , Hayashi Kenshi , Uchiyama Katsuharu , Nohara Atsushi , Fujino Noboru , Ino Hidekazu , Inazu Akihiro , Kobayashi Junji , Mabuchi Hiroshi , Yamagishi Masakazu
Published: April 2024

Introduction:
Autosomal recessive hypercholesterolemia (ARH) associated with mutations in LDLR adaptor protein 1 (LDLRAP1) gene is extremely rare disorder. Although this defect seems to be a phenocopy of homozygous familial hypercholesterolemia (FH), clinical phenotype of ARH seems less severe, more responsive to statins, the cause of which may be derived from the difference of remnant-like particles (RLP) clearance. Hypothesis: We assessed the hypothesis that the ability of RLP clearance of ARH subject was different from that of FH subject.

Methods:
OFTT cream (Jomo Shokuhin, Takasaki, Japan) 50 g was given per body surface area (squared meter), blood sampling was performed at 2 hour intervals up to 6 hour. Plasma lipoprotein and RLP fraction were determined by HPLC system in one ARH subject (68yr, LDL-C=286mg/dl), 4 heterozygous FH subjects (58±17yr, LDL-C=241±26mg/dl), and 4 controls (62±17yr, LDL-C=88±6mg/dl). All male subjects were selected to have apolipoprotein E2/E3 phenotype without diabetes. None of the subjects took medication known to affect plasma lipids at the time of this study for at least 4 weeks. The area under curve (AUC) of TG, RLP-TG, and RLP-cholesterol levels were evaluated.

Results:
After oral fat load, the AUC of TG, RLP-TG, and RLP-cholesterol levels of heterozygous FH subjects were significantly increased compared to those of controls (441±87 mg/dl*hour vs 316±133 mg/dl*hour, p<0.05, 126±60 mg/dl*hour vs 49±11 mg/dl*hour, p<0.05, 34±8 mg/dl*hour vs 23±11 mg/dl*hour, p<0.05, respectively). In contrast to these results, the AUC of TG, RLP-TG, and RLP-cholesterol levels of ARH were within the nomal range (310mg/dl*hour, 23mg/dl*hour, 22mg/dl*hour, respectively).

Conclusions:
These results suggest that the lack of LDLRAP1 modulates RLP metabolism, activating an alternate pathway which can remove remnant fraction paradoxically. This preferred pathway should contribute to the greater responsiveness to statins. Our results will provide new insights into the lipoprotein metabolism of ARH and the novel pharmacological target for LDLRAP1.
Abstract 8264: Exercise Training Improves Cardiac Function and Restores Nuclear Localization of pAKT in Aged Mice
Authors: El-Haddad Hazim , Champion Hunter C , Danner Thomas A , Rao Sandesh S , Mulhearn Thomas J , Haile Azeb , Gebska Milena , Hemnes Anna , Hager Matthew , Breton Matt , Mahmud Mobusher
Published: April 2024

Cardiovascular aging is frequently associated with atherosclerosis, hypertension, and vascular stiffening as well as significant functional and molecular changes that result in cardiac hypertrophy and the development of fibrosis. On a functional scale, aerobic exercise is known to induce physiologic hypertrophy and to improve cardiovascular performance. In this study we sought to determine the effectiveness of exercise in aged (24-26 month old) C57/BL6 mice as well as to explore potential mechanisms for any observed cardiovascular improvement. Old and young mice underwent exercise training by swimming for a period of six weeks. At the conclusion of the swim training, hemodynamic and molecular markers of cardiac function in old and young mice were assessed. We show that exercise training results in significant improvement in left ventricular (LV) function in older animals, a significant increase in ejection fraction (EF) and mean stroke work index (MSWI), and an improvement in the time constant of LV relaxation (Tau). Swim training also resulted in a reduction in aging-associated oxidative stress (42 +/-13% reduction in luminol activity when compared to old sedentary, P<0.05). In addition, aging was associated with a significant shift of pAKT from the nucleus to the cytosol and exercise training reversed this process. These findings demonstrate that swimming not only has a beneficial effect on cardiac function in the aged, but can also serve to mediate and even reverse the biological processes associated with age-related cardiovascular changes in the elderly.
Abstract 83: Sudden ETCO
2
Trend Change Alerts During Out-of-Hospital Cardiopulmonary Resuscitation Using an Automated Capnogram Analysis Algorithm
Authors: Daya Mohamud , Helfenbein Eric , Idris Ahamed , Edelson Dana , Firoozabadi Reza , Babaeizadeh Saeed , Zhou Sophia
Published: April 2024

Background
Capnography has recently become the standard-of-care for EMS personnel during out-of-hospital resuscitation to confirm tracheal tube (TT) placement and monitor quality of CPR. Although the instantaneous end-tidal CO2 (EtCO2) value is of importance, additional information can also be obtained from the EtCO2 trend. Current defibrillator/monitors do not provide alerts based on EtCO2 trends.

Objective
To develop a defibrillator-based capnogram analysis program to provide sudden EtCO2 trend change alerts that can be used to alert rescuers to a variety of conditions.

Methods
Capnogram recordings from 154 OHCA patients were collected between 2008 & 2010 from two EMS agencies based in Oregon & Texas. De-identified clinical charts containing EMS self-reports were also obtained which contained time histories of events. The capnogram trend algorithm contains both rising and falling detectors and uses the difference between 30-second averages of EtCO2 from two adjacent sliding windows. The rising detector uses a threshold of a 50% increase and the falling detector uses a 30% decrease threshold to trigger.

Results
Sudden change alerts (N = 533) generated by the algorithm were correlated with events in the EMS charts or determined by examination of EtCO2, ECG, and compression waveforms. Sudden EtCO2 falling events were associated with poorer quality or stopped chest compression, hyperventilation, TT tube misplaced or dislodged, and loss of organized rhythm. Sudden EtCO2 rise events were associated with resumed or improved chest compression, successful airway placement, improved ventilation following hyperventilation, probable ROSC, and external pacing (n = 1). The remaining sudden change alerts were associated with artifacts in the capnogram waveform or could not be correlated.

Conclusion
An automated capnogram analysis program can accurately detect sudden trend changes in EtCO2 and help EMS personnel identify important events during OHCA resuscitation.
Abstract 8303: Silica-Gold Nanoparticles and Mesenchymal Stem Cells versus Composite Ferro-Magnetic Approach for Management of Atherosclerotic Plaque and Artery Remodeling
Authors: Kharlamov Alexander , Perrish Alexander , Gabinsky Jan
Published: April 2024

Background.
Some modern angioplasty techniques generally just manipulate the form of the plaque and have some clinical and technical restrictions, relatively high complication rate and restenosis risk.

Methods.
A total of 180 patients with stable angina were randomly assigned to the three groups (60 patients into nanogroup with the use of 60/15-70/40 nm silica-gold nanoparticles (NPs) transplanted by endoscopic cardiac surgery in the composition of bioengineered on-artery patch grown on the basis of biopolymeric scaffold and host circulating CD45-CD34-CD73+CD105+ progenitor cells, 60 - into ferro-magnetic group with 60/15-70/40 nm silica-gold iron-bearing NPs with delivery in hand of magnetic navigation system, and 60 - in sirolimus-eluting stenting control). NPs were detonated with near-infrared laser irradiation on day 3 under the drug antithrombotic protection. We have used a modified method for the preparation of NPs as described by Lee (2008) and Deng H (2005). Studied proximal left anterior descending arteries were observed by 30 MHz intravascular ultrasound (IVUS).

Results.
A change of the plaque volume (PV, mm3) as-intervened/ in 9 months in groups were −24.3/ −66.8%, −29.5/ −42.3% and −11.4/ +4.3% (p<0.01) respectively. An impact over the non-organic part of the plaque (mineral deposits, calcium necrotic core) was predominated in nanogroup (−43.4% vs −12.1% and +3.7% respectively, p<0.005). While first 4 weeks, 3/60 (5%), 2/60 (3.3%), 7/60 (11.7%) cases of acute atherothrombosis were revealed in groups respectively (p<0.01). Restenosis confirmed in 3 (5%) patients of stenting group only. Event free survival (cardiac death, recurrent symptoms, MI) in 9 mns was 95, 91.7 and 85% in groups respectively (p<0.01). Coronary flow-mediated vasodilation was observed after hyperemia and injection of nitroglycerine (+10.2 and +16.6%, +8.2 and +9.6%, +8.1 and +9.8% in groups respectively, p<0.05).

Conclusion.
Nanoburning is the novel promising technique to demolish and melt the plaque especially in combination with stem cell technologies challenging functional restoration of the vessel. Plasmonics is the high-effective and safe alternative to stenting for angioplasty.
Abstract 8381: Safety and Effect of Adipose Tissue Derived Stem Cell Implantation in Patients with Critical Limb Ischemia
Authors: Lee Han Cheol , An Sung Gyu , Lee Hye Won , Yang Mi Jin , Oh Jun Hyuk , Choi Jung Hyun , Cha Kwang Soo , Hong Taek Jong
Published: April 2024

Adipose tissue-derived mesenchymal stem cells (ADSCs) are potent and effective for inducing regeneration of damaged tissue. Treatment of critical limb ischemia (CLI) is occasionally difficult through bypass operation or percutaneous vascular intervention. ADSC transplantation shows proangiogenic action in animal hindlimb ischemia models. We performed multiple intramuscular ADSC injections in CLI patients to treat diabetic foot and thromboangiitis obliterans (TAO) and assessed its safety and efficacy. The study included 15 CLI patients (15 men, median age: 52 years, range: 24-73 years) with ischemic resting pain in one limb with/without nonhealing ulcers and necrotic foot (Rutherford class II-4: n = 3, III-5: n = 9, III-6: n = 3) who did not undergo nonsurgical or surgical revascularization. ADSCs were isolated from adipose tissue of TAO patients (B-ADSCs), diabetes patients (D-ADSCs), and healthy donors (control ADSCs) by using 0.075% collagenase digestion. In a colony forming unit (CFU) assay using stromal vascular fraction, B-ADSCs and D-ADSCs yielded lesser colonies than normal ADSCs. However, culture-expanded B-ADSCs showed normal proliferation ability compared to control ADSCs. Adipogenic and osteogenic differentiation potential did not differ between B-ADSCs and control ADSCs. Culture-expanded D-ADSCs showed lower proliferation ability and osteogenic differentiation and higher adipogenic differentiation than control ADSCs. Multiple intramuscular ADSC injections cause no complications during the follow-up period (mean follow-up time: 6 months). Clinical improvement occurred in 66.7% of patients. Five patients required minor amputation during follow-up. All amputation sites healed completely. At 6 months, significant improvement was noted on pain rating scales and in claudication walking distance. Digital subtraction angiography (DSA) before and 6 months after ADSC implantation showed formation of numerous vascular collateral networks across affected arteries. Multiple intramuscular ADSC injections may be a safe alternative to achieve therapeutic angiogenesis in patients with CLI who are refractory to other treatment modalities
Abstract 84: Hyperventilation Alert During Out-of-Hospital Cardiopulmonary Resuscitation Using an Automated Capnogram Analysis Algorithm
Authors: Daya Mohamud , Helfenbein Eric , Idris Ahamed , Edelson Dana , Firoozabadi Reza , Babaeizadeh Saeed , Zhou Sophia
Published: April 2024

Background
Hyperventilation during cardiopulmonary resuscitation (CPR) inhibits venous blood return, decreases coronary perfusion pressure, and is associated with decreased survival rates. Accurate computation of ventilation rate during CPR by defibrillator-based algorithms is difficult due to artifact induced on impedance waveforms. Real time capnography may help detect inadvertent hyperventilation during resuscitation.

Objective
To evaluate an automated defibrillator-based capnogram (CO2) analysis method to alert for excessive ventilation rate in the presence of low end-tidal CO2 (EtCO2).

Methods
Recordings from 270 OHCA patients with capnogram waveforms were collected between 2008 and 2010 from two EMS agencies based in Oregon and Texas. The hyperventilation detection algorithm was added to a previously reported EtCO2 analysis program. The hyperventilation algorithm employs exponentially-weighted moving-average filtering (alpha=0.25) to compute respiration rate (RR) and EtCO2 trends from individual breath-breath intervals and breath EtCO2 measurements. A combination of RR and EtCO2 is used in the decision tree. The algorithm was tested using a threshold of RR > 12 bpm and EtCO2 < 20 mmHg. The added requirement of a low EtCO2 avoids false detection on post-resuscitation spontaneous respirations which are unlikely to have low EtCO2. Hyperventilation alerts generated by algorithm were manually validated by two reviewers who had access to CO2, ECG, compression, and impedance-based respiration waveforms.

Results
The automated program generated 414 hyperventilation alerts in 148 (55%) patients. A total of 24 alerts were identified as false positive due to artifacts in the capnogram waveform. No false negative alert was identified. This yields an algorithm sensitivity of 100% and positive-predictive value 94%. During validated hyperventilation, the average maximum ventilation rate was 25 ±11 bpm, with an average minimum EtCO2 of 6 ±4 mmHg.

Conclusion
Hyperventilation is common in OHCA resuscitation. An automated capnogram analysis method can accurately detect episodes of hyperventilation and has the potential to alert EMS personal to excessive ventilation rates during OHCA resuscitation.
Abstract 8423: Prevalence and Outcomes of Intermediate Saphenous Vein Graft Lesions: Findings from the Stenting of Saphenous Vein Grafts Randomized-Controlled Trial
Authors: Abdel-karim Abdul-rahman R , da Silva Monica , Lichtenwalter Christopher , de Lemos James A , Obel Owen , Addo Tayo , Roesle Michele , Haagen Donald , Rangan Bavana V , Makke Lorenza , Jeroudi Omar M , Raghunathan Deepa , Saeed Bilal , Bissett Joseph K , Sachdeva Rajesh , Voudris Vassilios V , Karyofillis Panagiotis , Kar Biswajit , Rossen James , Fasseas Panayotis , Berger Peter , Banerjee Subhash , Brilakis Emmanouil S
Published: April 2024

Background:
We sought to examine the prevalence and progression rate of intermediate SVG lesions in the Stenting Of Saphenous vein grafts (SOS) trial.

Methods:
The baseline and follow-up angiograms of the 80 patients participating in the SOS trial were analyzed to determine the prevalence of intermediate (30-60% angiographic diameter stenosis) SVG lesions and their progression rate.

Results:
At least one intermediate SVG lesion was present in 31 of 143 (22%) SVGs in 27 of 80 (34%) patients. Patients with intermediate SVG lesions were older and more likely to present with myocardial infarction. Most intermediate lesions were present in the vein grafts the required stents (20 grafts in 19 patients). During a median follow-up of 35 months, angiographic follow-up was available for 28 grafts in 25 patients. Progression (defined as percent diameter stenosis ≥70% but <100% at follow-up angiography) was seen in 11 of 28 SVGs (39%) in 11 of 25 patients (44%). The rate of progression of the intermediate lesion at 12, 24 and 36 months was 28% and 47% and 84%, respectively (Figure). Seven of 11 patients (64%) whose intermediate SVG lesion progressed presented with an acute coronary syndrome, and 8 (73%) underwent a percutaneous coronary intervention. Four of the 28 grafts with intermediate lesions at baseline were occluded at follow-up; all of those SVGs had received a stent as part of the SOS trial.

Conclusions:
Among patients undergoing SVG lesion stenting, intermediate SVG lesions are common, have high rates of progression, and frequently present as an acute coronary syndrome.
Abstract 8460: High-Sensitivity Cardiac Troponin T and the Risk of Incident Atrial Fibrillation: The Atherosclerosis Risk in Communities (ARIC) Study
Authors: Filion Kristian B , Agarwal Sunil K , Ballantyne Christie M , Hoogeveen Ron C , Huxley Rachel R , Loehr Laura R , Nambi Vijay , Soliman Elsayed Z , Alonso Alvaro
Published: April 2024

Introduction:
Structural changes in the heart, such as increased left atrial size and decreased ejection fraction, are known risk factors for atrial fibrillation (AF). An association between cardiac troponin T (hs-cTnT), a marker of myocardial cell damage measured with a high sensitivity assay, and the risk of AF could have implications for AF risk stratification.

Objective:
To estimate the association between hs-cTnT and the risk of incident AF in the Atherosclerosis Risk in Communities (ARIC) Study, a prospective cohort of middle-aged adults from 4 U.S. communities.

Methods:
Study was restricted to 10,596 participants free of AF at the fourth clinic visit (1996-98). AF was defined using ICD codes from hospitalizations and death certificates. Cox proportional hazards models were used to estimate the association between hs-cTnT and the risk of AF adjusting for potential confounders (Table). Net reclassification index (NRI) was used to examine its discriminative ability for 10-year AF risk (<5%, 5-15%, and >15%).

Results:
We observed 920 incident AF cases over 109,607 person-years. The AF rate was lowest among participants with undetectable hs-cTnT levels and greatest among those with hs-cTnT > 0.014 µg/L (Table). After adjustment for potential confounders, a 1 standard deviation difference in ln(hs-cTnT) was associated with a hazard ratio of 1.21 (95% CI = 1.13, 1.30). Addition of hs-cTnT to known AF predictors did not increase the area under the curve appreciably (without hs-cTnT: 0.755, 95% CI = 0.740, 0.771; with hs-cTnT: 0.759, 95% CI = 0.743, 0.774). Among those who developed AF, 3.2% had their risk increased by the inclusion hs-cTnT and 3.9% had their risk decreased (p=0.50). Among those who did not develop AF, 2.7% had their risk increased and 3.4% had their risk decreased (p=0.0001). There was no net improvement in risk stratification (NRI=0.36%, p=0.72).

Conclusions:
Hs-cTnT level is associated with an increased rate of AF but did not improve risk stratification.
Abstract 8500: Alcohol Effect on Incident Atrial Fibrillation in Individuals with Cardiovascular Disease: Analysis of Data from the ONTARGET and TRANSCEND Studies
Authors: Liang Yan , Mente Andrew , Yusuf Salim , Gao Peggy , Teo Koon K ,   ONTARGET and TRANSCEND Investigators
Published: April 2024

The relationship of alcohol consumption with atrial fibrillation (AF) is inconsistent, and little is known about the impact of alcohol intake on AF incidence in older people with cardiovascular diseases (CVD) or diabetes.

The purpose of this analysis is to assess the association between alcohol consumption and incident AF among older individuals with CVD or diabetes mellitus with end organ damage.

A cohort of individuals (n=30,430) without AF at baseline, aged ≥55 years, with established CVD or high risk diabetes mellitus, and participating in two randomized trials, the ONTARGET or TRANSCEND (median follow-up of 56 months), were included in the analysis. Alcohol intake was classified as low (Group 1, <1 drink/week, referent), medium (Group 2, 1-14 drinks/week for women and 1-21 drinks/week for men) and high (Group 3, >14 drinks/week for women or >21 drinks/week for men) consumption, according to the World Health Organization recommendations. Multivariable Cox regression was used to model the relationship between alcohol intake and incident AF.

There were 2093 new onset AF events in these patients. The age- and sex-standardized incidence rates were 14.47, 17.29 and 20.89 events per 1000 person years in Group 1, 2 and 3, respectively with an additional 6.42 events per 1000 person years in high compared to low alcohol consumers. The unadjusted and adjusted hazard ratios of incident AF associated with alcohol intake were shown in the Table. A significant linear dose response relationship was found (p for trend <0.0001 and =0.0019, respectively in the unadjusted and full-adjusted models).

In conclusion, moderate alcohol intake is associated with an increased incidence of AF in older individuals with CVD or diabetes mellitus and in a linear fashion with increasing consumption. Recommendations made about the protective effects of moderate alcohol intake in patients at high risk of CVD should be tempered with this new finding.