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    Association of Area Deprivation Index and hypertension, diabetes, dyslipidemia, and obesity: a cross-sectional study of the HABS-HD cohort.
    (2023) Seyedahmadi, Armin; Vintimilla, Raul; Hall, James; Johnson, Leigh; O'Bryant, Sid
    Background: Heart disease is a leading cause of death globally and the prevalence of cardiovascular disease (CVD) is expected to increase significantly in the United States over the next decade. Previous research has shown that socioeconomic status has a significant impact on CVD prevalence and outcomes, with risk factors for CVD being more prevalent in individuals from low socioeconomic groups. We aimed to investigate the association between neighborhood deprivation and the prevalence of major CVD risk factors (hypertension, diabetes, dyslipidemia, and obesity) in a Mexican American population compared to Non-Hispanic Whites. Methods: A cross-sectional analysis was conducted to include 1867 subjects. 971 self-identified as Mexican American (MA), and 896 as Non-Hispanic White (NHW). These participants underwent a clinical interview, neuropsychological exam battery, functional examination, MRI of the head, amyloid PET scan, and blood draw for clinical and biomarker analysis. They were also assigned an ADI score based on participants living in the best and worst neighborhoods according to Area Depravation Index (ADI) model. Results: Sixty percent of the sample was female. MA were significantly younger (mean age 63.37 vs 68.64) and less educated (mean education years 9.69 vs 15.61 than NHW. Additionally, MA had a significantly higher prevalence of HTN, DM, and obesity. Only 12.3% of Non-Hispanic Whites lived in the most deprived neighborhoods (percentile 4), while 57.5% of Mexican Americans lived in the percentile 4 ranking areas (p≤ .05). There was a significant difference between non-Hispanic White participants living in the least deprived neighborhoods compared to participants living in the most deprived neighborhoods for HTN (OR = 2.14, 95% CI [1.31, 3.48]), DM (OR = 3.42; 95% CI [1.67, 7.01]), and obesity (OR = 3.03, 95% CI [1.86 to 4.95]). There was no significant difference in the odds of having dyslipidemia between non-Hispanic Whites living in the ADI quartile 1 when compared to those living in the ADI quartile 4. These results remained significant after adjusting for age, sex, education, and cardiovascular risk factors. Conclusion: In conclusion, this study found the area deprivation index (ADI) is associated with cardiovascular risk factors such as hypertension, diabetes, dyslipidemia, and obesity. These findings suggest that socioeconomic status may play a role in the prevalence of certain health conditions among different ethnic groups. Further research is needed to understand the underlying mechanisms and to develop interventions that address health disparities among different ethnic populations.
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    The Incidence of Distal Extremity Necrosis Associated with Vasopressor use in Critically Ill Patients
    (2023) Beeton, George; Doederlein, Alexander R.; Loeffelholz, Zachary; Pientka, William; Pientka, Amanda
    Purpose: Medication adverse events are associated with significant morbidity and mortality, increased hospital length of stay, and create a high burden of cost for both the patient and the healthcare system. Vasopressors are a class of medication with a known association with digital necrosis due to excessive peripheral vasoconstriction, in order to prioritize blood flow to the vital organs. We aim to identify the incidence of distal extremity necrosis in critically ill patients receiving vasopressors for cardiovascular support. Methods: A retrospective analysis was performed of all patients treated with vasopressors including epinephrine, norepinephrine, phenylephrine, and vasopressin during the study period: January 1, 2012, through December 31, 2020, at a single institution. Patients treated with vasopressors with a concomitant documented diagnosis of distal extremity (upper and/or lower) ischemia, gangrene, or necrosis were identified. This subset of patients underwent further chart review to confirm the onset of digital necrosis was within 4 months of vasopressor use. The incidence of distal extremity necrosis in critically ill patients receiving vasopressors for cardiovascular support was then calculated. Results: A total of 1,980,300 patients were screened, of which 46,792 had documented vasopressor use and were included in the at-risk population. Of all patients that had received vasopressors within our study period, 1,151 also had a documented diagnosis of distal extremity necrosis. Overall, a total of 56 (0.12%) patients had documented distal extremity necrosis within 4 months after sustained vasopressor use. 31 patients (36.1%) were given 3 or 4 vasopressors concurrently, 28 (50%) had isolated toe and/or foot necrosis, 15 (26.8%) had necrosis of both the distal upper and lower extremities, and 13 (23.2%) developed necrosis isolated to the hand and/or fingers. The average age of those who developed digital necrosis was 59 years. While there was more distal extremity necrosis when multiple pressors were used concurrently, the association was not significant (p=0.77) Conclusion: The use of vasopressors for cardiac support in critically ill patients is often unavoidable. This treatment comes with the risk of inducing distal extremity ischemia and necrosis. The incidence of distal extremity necrosis is extremely low, but the risk increases when multiple vasopressors are used concurrently.
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    A Rare Occurrence of Cardiogenic Shock after Cardioversion: A Case Report
    (2023) Jain, Kunal; Fajkus, Austin; Takata, Theodore
    Background: Atrial fibrillation (AF) is a common cardiac arrhythmia that affects the health and lifespan of people and has been growing in prevalence with the aging population. AF leads to atrial remodeling, which increases the likelihood of developing treatment resistant AF. Risk factors for AF include obstructive sleep apnea, alcohol use, obesity, hypertension, and diabetes. Treatment consists of rhythm control, rate control, and thromboembolism prevention. If a patient fails to convert to sinus rhythm or remains symptomatic despite pharmacological treatment, the next step in management may include Direct Current Cardioversion (DCCV) or catheter ablation. DCCV restores sinus rhythm (SR) by using controlled shocks to the heart and is considered a safe and effective procedure for treating AF. Complications include arrhythmias, skin burns, and cardiac tissue damage. Following the restoration of SR, cardiac output (CO) generally improves. Cardiogenic shock is a rare occurrence after DCCV. This case report details one of these rare occurrences, where a patient with multiple comorbidities developed cardiogenic shock after DCCV for AF. Case Information: A 65-year-old male with a history of heart failure with reduced ejection fraction, AF with prior ablation, atrial flutter, dilated cardiomyopathy, obstructive sleep apnea, chronic kidney disease, and implantable cardioverter defibrillator (ICD), presented to the emergency department (ED) with symptoms of dyspnea and shortness of breath. ECG showed atrial flutter with rapid ventricular response (RVR). Urgent DCCV was performed, restoring SR but precipitating cardiogenic shock, which required intubation and vasopressors. Since stroke volume remains constant in patients with dilated cardiomyopathy, the ICD was reprogrammed to raise the HR. Thereby improving the CO and resolving the cardiogenic shock. The patient remained stable for one month but had recurrent decompensated heart failure. ECG showed AF with RVR with a HR greater than 130 bpm. The patient was cardioverted again to sinus rhythm. However, the patient's condition soon deteriorated, wherein he developed shortness of breath, orthopnea, diaphoresis, and cold extremities. He was intubated due to his respiratory distress and started on milrinone, norepinephrine, furosemide, and an amiodarone drip. He nonetheless converted to AF with RVR, compromising his CO. This was evident clinically by his decrease in urine output, despite furosemide treatment. Urgent AV node ablation with a biventricular ICD upgrade was thus recommended. Postoperatively, as his condition improved, the patient was extubated and switched to oral diuretics. Amiodarone was discontinued, and his heart failure medications were slowly reinstated. Upon discharge, the patient was referred to another facility that specializes in heart failure and transplants. Conclusion: Although DCCV is generally considered a safe and effective procedure, there are still risks associated with it. This case highlights the importance of considering underlying cardiac dysfunction in patients undergoing cardioversion for AF and the need for close monitoring and follow-up in these patients. Since not many cases showcasing these potential complications have been documented, this warrants further research to identify risk factors, complications, and ways to prevent harm to patients who may undergo DCCV.
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    The Success Rate of Cryoablation vs. Radiofrequency Ablation for the Treatment of Atrial Fibrillation
    (2023) Navid, Daniel; Rice, Ellie; Gill, Lily; Campbell, Blake; Dutta, Arpam
    Atrial fibrillation (AF) is a heart rhythm disorder of the atrium caused by impulses that attack the Atrioventricular (AV) node and block signals to the ventricles. There are two types of catheter ablations that attempt to cure AF: radiofrequency (RF) ablation and cryoablation. RF ablations use an irrigated open-tip catheter to burn lesions in a point-by-point fashion around the pulmonary veins to stop the irregular electrical signals. Cryoablations use a balloon catheter that inflates in the pulmonary vein to freeze the tissue, which stops the irregular electrical signals. While both methods are adequate, the more effective procedure is a topic of debate. This study was performed at Baylor Scott and White Hillcrest hospital in the Cardiology Department. The data was obtained from 45 patients who suffered from AF from January 2017- June 2018. The purpose of this study was to evaluate the success rates of RF ablations and cryoablations within the Baylor Scott and White Hillcrest hospitals by measuring the readmission rates of patients who repeated an ablation. The initial success rates of RF ablation and cryoablation were calculated to be 88% and 95%, respectively. Even though this study aligns with other studies performed by Frankel Cardiovascular Center and CarolinaEast Medical Center, it was noted that the sample pool is small and limited to Baylor Scott and White Hillcrest.
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    Effects of the thromboxane receptor antagonist S18886 in the porcine coronary circulation
    (2023) Tucker, Selina M.; Warne, Cooper; Essajee, Salman; Goulopoulou, Styliani; Dick, Gregory; Tune, Johnathan
    Thromboxane A2 (TxA2) is a potent coronary vasoconstrictor that has been implicated in promoting decreases in myocardial perfusion in a variety of (patho)-physiologic conditions. S18886 is a promising orally-active TxA2 receptor antagonist currently approved for investigational clinical use. However, the coronary vascular effects of S18886 are unknown and its specificity and affinity for the thromboxane receptor in the coronary circulation remain unclear. We tested the hypothesis that administration of S18886 dose-dependently attenuates coronary vasoconstriction to the TxA2 mimetic U46619 without influencing coronary responses to prostaglandin F2α, acetylcholine, or smooth muscle depolarization (K+). Experiments to test this hypothesis were performed in male (n = 5) and female (n = 6) domestic swine. Hearts were excised and the left circumflex coronary artery isolated, cleaned of periadventitial fat, and cut into 3 mm rings. Isometric tension of coronary artery rings was measured in response to log order increments of U46619 (1 nM to 1 µM) with and without S18886 (0.1-100 nM). Similar isometric studies were conducted with prostaglandin F2α (10 nM-10 µM), acetylcholine (0.1-10 µM), and KCl (5-90 mM). U46619 induced concentration dependent increases in tension development of isolated coronary artery rings (average EC50 of 42 ± 19 nM). Incubation of coronary arteries with S18886 (1 nM) significantly attenuated coronary vasoconstriction to U46619 resulting in a rightward shift of the EC50 to 187 ± 38 nM (P < 0.02). Vehicle had no effect on U46619-induced contractions. Higher concentrations of S18886 dose-dependently reduced U46619-induced contractions. S18886 (1 nM) antagonized coronary vasoconstriction of prostaglandin F2α (10 µM) by 68% ± 5 (P < 0.0001) but had no effect on either acetylcholine or KCl-induced contraction. Data from this investigation indicate that S18886 is an effective antagonist of U46619-induced vasoconstriction in the porcine coronary circulation. While S18886 does not influence coronary smooth muscle response to either acetylcholine or activation of L-type Ca2+ channels, attenuation of prostaglandin F2α suggests antagonists specificity may extend beyond TxA2 receptor signaling.
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    Peripheral Vascular Function is Not Correlated to Subjective Sleep Quality in Young Healthy Humans
    (2023) Stanteen, Chandler; Davis, K. Austin; Bhuiyan, Nasrul; McIntyre, Benjamin; Rickards, Caroline
    Background: Peripheral vascular dysfunction (including endothelial dysfunction) may be an early biomarker of cardiovascular disease. Prior studies have shown a relationship between poor sleep quality and impaired vascular function, indexed by flow-mediated dilation (FMD) of the brachial artery. However, these investigations did not allometrically scale for baseline artery diameter, nor control for shear stress, which both affect the magnitude of flow-mediated vasodilation. Without scaling for baseline artery diameter, FMD may overestimate the magnitude of dilation in individuals with small baseline diameters. Additionally, greater shear stress will elicit a greater magnitude of vasodilation via release of vasoactive mediators from the endothelium, such as nitric oxide. With the quality of sleep declining in the United States, and cardiovascular disease remaining a leading cause of mortality, we sought to further explore the relationship between sleep quality and peripheral vascular function corrected for both baseline artery diameter and the magnitude of shear stress. Hypothesis: Poor sleep quality is associated with impaired peripheral vascular function indexed by "corrected” brachial artery FMD. Methods: Thirteen young and healthy human participants (7M, 6F) completed the Pittsburgh Sleep Quality Index (PSQI) survey prior to assessment of brachial artery FMD. PSQI scores range from 0-21, with higher scores indicating worse sleep quality. Brachial artery diameter and blood velocity were then obtained via duplex Doppler ultrasound during a 2-min baseline, a 5-min occlusion of the brachial artery, and a 3-min reactive hyperemia period. FMD of the brachial artery was calculated as the percent change from baseline diameter to the maximum diameter induced by reactive hyperemia. Shear stress was estimated as shear rate, calculated as eight times the ratio of brachial artery blood velocity to diameter. FMD was corrected for baseline diameter, and the shear stress area under the curve up to maximum diameter via ANCOVA (i.e., "corrected FMD”). Pearson correlations were calculated between PSQI score and uncorrected FMD, and between PSQI score and ANCOVA corrected FMD. Results: The mean PSQI score was 5.3 ± 4.5 (range, 0-17), and mean FMD was 5.0 ± 2.2 % (range, 2.7-9.4 %). While an unexpected modest positive correlation was observed between uncorrected FMD and PSQI score (r=0.51, p=0.08), corrected FMD and PSQI score were not correlated (r=0.38, p=0.25). Conclusion: There was no relationship between subjective sleep quality and peripheral vascular function as measured by corrected FMD in this cohort of young and healthy participants. These findings likely reflect the multivariate nature of vascular function in young healthy adults with lower cardiovascular risk, and the subsequent narrow range of both flow-mediated dilation and subjective sleep quality.
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    The length-tension characteristics of small coronary arteries vary with transmural origin
    (2023) Essajee, Sal; Warne, Cooper; Tucker, Selina; Dick, Gregory; Tune, Johnathan
    There are transmural differences in the structure of arteries across the left ventricular wall. For example, for arteries of the same size, wall thickness is greater in arteries of the epicardium than those from the endocardium. This observation suggests that there could be differences in their passive and active length-tension relationships, as different amounts of connective tissue or smooth muscle would be expected to alter these characteristics. We tested this hypothesis by studying similarly sized porcine coronary arteries from opposite transmural locations. Endocardial arteries had a diameter of 389 ± 33 µm (n = 8), while epicardial arteries measured 388 ± 50 µm (n = 6). A wire myograph was used to study the mechanical properties of these arteries under isometric conditions in KrebsHenseleit buffer at 37 oC. Arteries were cut into rings with an axial length of 2 mm. Rings were repetitively stimulated to contract at increasing lengths with the addition of high extracellular K + (80 mM). Coronary arteries developed active tension to a plateau level over approximately 3-5 min and K + -induced contractions readily washed out. Arteries from the epicardium were stiffer, as the passive-length tension curve of these vessels was elevated over arteries from the endocardium. Passive tensions at optimal length were 3.2 ± 0.4 vs. 5.6 ± 1.5 mN/mm (p < 0.05). The active tension developed in response to K + depolarization was greater in epicardial arteries. Active tensions at optimal length were 3.4 ± 1.1 vs. 2.4 ± 0.3 mN/mm (p < 0.05). Our results represent the first comparison of transmural differences in coronary arteries under isometric tension. Our findings support the hypothesis that differences exist in the passive and active length-tension relationships of epicardial and endocardial arteries that correlate with wall thickness.
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    Creation of an Affordable and Realistic Ultrasound Pericardiocentesis Model
    (2023) Katigbak, Kyle; Muyskens, Steve; Selby, Samuel; Vierkant, Luke
    Purpose The pericardium is a protective fluid filled sac that surrounds the heart. In cardiac tamponade, the pericardium fills with excess fluid (blood, pus, etc.) resulting in decreased cardiac output. Ultrasound guided pericardiocentesis is a dangerous, but potentially lifesaving procedure that can be performed to relieve cardiac tamponade. Teaching institutions often obtain lifelike trainers that cost upwards of $20,000. More cost-effective models using balloons or Styrofoam eggs have been created but lack realism and durability. Our objective was to develop an affordable model utilizing a 3D printed heart for ultrasound-guided pericardiocentesis. Methods Models of the heart and pericardium were created using Mimics 3D software (Materialise) and printed on a Stratasys J750 printer utilizing Digital Anatomy materials. An alternative model was created utilizing a cup and saline IV bag. Gel wax was then melted at 220 degrees Fahrenheit and the two models were submerged to simulate the acoustic properties of surrounding thoracic tissues. Results The 3D model and alternative model were successfully created and ultrasound-guided pericardiocentesis was attempted. The echogenicity of the 3D printed pericardium was sufficient for visualization; however, the material was too thick to penetrate. In the alternative model, the saline IV bag was amenable to needle puncture, but was anechoic preventing sufficient visualization and did not sufficiently reseal after needle removal. Conclusion While gel wax has appropriate ultrasound properties, a material that can reseal after needle insertion is needed to make plastic bags and cups viable alternatives. Additional trials need to be done to identify a material for the 3D printed pericardium that is compatible with both ultrasound and repeat procedure attempts. Overall, 3D printing offers the most promising results and with future attempts, after fine-tuning the thickness of the pericardial sac, we anticipate a successful model will be produced.