Browsing by Subject "Coronary vessels"
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Item Coronary CTA plaque volume severity stages according to invasive coronary angiography and FFR(Elsevier, 2022) Min, James K.; Chang, Hyuk-Jae; Andreini, Daniele; Pontone, Gianluca; Guglielmo, Marco; Bax, Jeroen J.; Knaapen, Paul; Raman, Subha V.; Chazal, Richard A.; Freeman, Andrew M.; Crabtree, Tami; Earls, James P.; Medicine, School of MedicineBackground: Atherosclerotic plaque characterization by coronary computed tomography angiography (CCTA) enables quantification of coronary artery disease (CAD) burden and type, which has been demonstrated as the strongest discriminant of future risk of major adverse cardiac events (MACE). To date, there are no clinically useful thresholds to assist with understanding a patient's disease burden and guide diagnosis and management, as there exists with coronary artery calcium (CAC) scoring. The purpose of this manuscript is to establish clinically relevant plaque stages and thresholds based on evidence from invasive angiographic stenosis (ICA) and fractional flow reserve (FFR) data. Methods: 303 patients underwent CCTA prior to ICA and FFR for an AHA/ACC clinical indication. Quantitative computed tomography (QCT) was performed for total plaque volume (TPV, mm3) and percent atheroma volume (PAV, %). We segmented atherosclerosis by composition for low-density non-calcified plaque (LD-NCP), non-calcified plaque (NCP), and calcified plaque (CP). ICAs were evaluated by quantitative coronary angiography (QCA) for all coronary segments for % diameter stenosis. The relationship of atherosclerotic plaque burden and composition by QCT to ICA stenosis extent and severity by QCA and presence of ischemia by FFR was assessed to develop 4 distinct disease stages. Results: The mean age of the patients was 64.4 ± 10.2 years; 71% male. At the 50% QCA stenosis threshold, QCT revealed a mean PAV of 9.7 (±8.2)% and TPV of 436 (±444.9)mm3 for those with non-obstructive CAD; PAV of 11.7 (±8.0)% and TPV of 549.3 (±408.3) mm3 for 1 vessel disease (1VD), PAV of 17.8 (±9.8)% and TPV of 838.9 (±550.7) mm3 for 2VD, and PAV of 19.2 (±8.2)% and TPV of 799.9 (±357.4) mm3 for 3VD/left main disease (LMD). Non-ischemic patients (FFR >0.8) had a mean PAV of 9.2 (±7.3) % and TPV of 422.9 (±387.9 mm3) while patients with at least one vessel ischemia (FFR ≤0.8) had a PAV of 15.2 (±9.5)% and TPV of 694.6 (±485.1). Definition of plaque stage thresholds of 0, 250, 750 mm3 and 0, 5, and 15% PAV resulted in 4 clinically distinct stages in which patients with no, nonobstructive, single VD and multi-vessel disease were optimally distributed. Conclusion: Atherosclerotic plaque burden by QCT is related to stenosis severity and extent as well as ischemia. We propose staging of CAD atherosclerotic plaque burden using the following definitions: Stage 0 (Normal, 0% PAV, 0 mm3 TPV), Stage 1 (Mild, >0-5% PAV or >0-250 mm3 TPV), Stage 2 (Moderate, >5-15% PAV or >250-750 mm3 TPV) and Stage 3 (Severe, >15% PAV or >750 mm3 TPV).Item Impact of Opioid and Nonopioid Drugs on Postsurgical Pain Management in the Rat(Hindawi Publishing Corporation, 2016) Wilson, Natalie M.; Ripsch, Matthew S.; White, Fletcher A.; Department of Anesthesia, IU School of MedicineAim. Nonsteroidal anti-inflammatory drugs or opioids are commonly used to control surgical pain following veterinary and clinical procedures. This study evaluated the efficacy of postoperative ketorolac or buprenorphine following abdominal surgery. Main Methods. Mean arterial pressure (MAP), heart rate, animal activity, corticosterone levels, and a nociceptive sensitivity assay were used to evaluate 18 adult male Sprague-Dawley rats which underwent aortic artery occlusion for implantation of a radiotelemetry device. The animals were treated postoperatively with intraperitoneal injections of vehicle, ketorolac (10 mg/kg), or buprenorphine (0.06 mg/kg) every 8 hours for 3 days. Key Findings. There were no consistent significant changes in any of the telemetry parameters after treatment with ketorolac compared with no saline treatment with the exception of increased MAP in the buprenorphine group during the first 48 hours when compared with other treatment groups. There was a sustained increase in fecal corticosterone levels from baseline on days 2-7 with buprenorphine compared with vehicle- or ketorolac-treated animals. All treatment conditions displayed reduced paw withdrawal thresholds (PWTs) from day 1 to day 21 following surgery. Compared with the vehicle treatment group, buprenorphine-treated animals exhibited significantly lower PWT levels from day 4 to 14 days. Significance. Given the prolonged increase in fecal corticosterone levels and pronounced changes in tactile hyperalgesia behavior in rodents subjected to buprenorphine treatment, these data suggest that ketorolac may be superior to buprenorphine for the treatment of postprocedure pain behavior in rodents.Item IVUS Validation of Patient Coronary Artery Lumen Area Obtained from CT Images(Public Library of Science, 2014-01-29) Luo, Tong; Wischgoll, Thomas; Koo, Bon Kwon; Huo, Yunlong; Kassab, Ghassan S.; Surgery, School of MedicineAims: Accurate computed tomography (CT)-based reconstruction of coronary morphometry (diameters, length, bifurcation angles) is important for construction of patient-specific models to aid diagnosis and therapy. The objective of this study is to validate the accuracy of patient coronary artery lumen area obtained from CT images based on intravascular ultrasound (IVUS). Methods and results: Morphometric data of 5 patient CT scans with 11 arteries from IVUS were reconstructed including the lumen cross sectional area (CSA), diameter and length. The volumetric data from CT images were analyzed at sub-pixel accuracy to obtain accurate vessel center lines and CSA. A new center line extraction approach was used where an initial estimated skeleton in discrete value was obtained using a traditional thinning algorithm. The CSA was determined directly without any circular shape assumptions to provide accurate reconstruction of stenosis. The root-mean-square error (RMSE) for CSA and diameter were 16.2% and 9.5% respectively. Conclusions: The image segmentation and CSA extraction algorithm for reconstruction of coronary arteries proved to be accurate for determination of vessel lumen area. This approach provides fundamental morphometric data for patient-specific models to diagnose and treat coronary artery disease.Item KMT2D-NOTCH Mediates Coronary Abnormalities in Hypoplastic Left Heart Syndrome(American Heart Association, 2022) Yu, Zhiyun; Zhou, Xin; Liu, Ziyi; Pastrana-Gomez, Victor; Liu, Yu; Guo, Minzhe; Tian, Lei; Nelson, Timothy J.; Wang, Nian; Mital, Seema; Chitayat, David; Wu, Joseph C.; Rabinovitch, Marlene; Wu, Sean M.; Snyder, Michael P.; Miao, Yifei; Gu, Mingxia; Radiology and Imaging Sciences, School of MedicineItem Mild Anastomotic Stenosis in Patient-Specific CABG Model May Enhance Graft Patency: A New Hypothesis(Public Library of Science, 2013-09-13) Huo, Yunlong; Luo, Tong; Guccione, Julius M.; Teague, Shawn D.; Tan, Wenchang; Navia, José A.; Kassab, Ghassan S.; Surgery, School of MedicineIt is well known that flow patterns at the anastomosis of coronary artery bypass graft (CABG) are complex and may affect the long-term patency. Various attempts at optimal designs of anastomosis have not improved long-term patency. Here, we hypothesize that mild anastomotic stenosis (area stenosis of about 40-60%) may be adaptive to enhance the hemodynamic conditions, which may contribute to slower progression of atherosclerosis. We further hypothesize that proximal/distal sites to the stenosis have converse changes that may be a risk factor for the diffuse expansion of atherosclerosis from the site of stenosis. Twelve (12) patient-specific models with various stenotic degrees were extracted from computed tomography images using a validated segmentation software package. A 3-D finite element model was used to compute flow patterns including wall shear stress (WSS) and its spatial and temporal gradients (WSS gradient, WSSG, and oscillatory shear index, OSI). The flow simulations showed that mild anastomotic stenosis significantly increased WSS (>15 dynes · cm(-2)) and decreased OSI (<0.02) to result in a more uniform distribution of hemodynamic parameters inside anastomosis albeit proximal/distal sites to the stenosis have a decrease of WSS (<4 dynes · cm(-2)). These findings have significant implications for graft adaptation and long-term patency.Item Numerical Simulation and Clinical Implications of Stenosis in Coronary Blood Flow(Hindawi, 2014) Zhang, Jun-Mei; Zhong, Liang; Luo, Tong; Huo, Yunlong; Tan, Swee Yaw; Wong, Aaron Sung Lung; Su, Boyang; Wan, Min; Zhao, Xiaodan; Kassab, Ghassan S.; Lee, Heow Pueh; Khoo, Boo Cheong; Kang, Chang-Wei; Ba, Te; Tan, Ru San; Biomedical Engineering, Purdue School of Engineering and TechnologyFractional flow reserve (FFR) is the gold standard to guide coronary interventions. However it can only be obtained via invasive angiography. The objective of this study is to propose a noninvasive method to determine FFRCT by combining computed tomography angiographic (CTA) images and computational fluid dynamics (CFD) technique. Utilizing the method, this study explored the effects of diameter stenosis (DS), stenosis length, and location on FFRCT. The baseline left anterior descending (LAD) model was reconstructed from CTA of a healthy porcine heart. A series of models were created by adding an idealized stenosis (with DS from 45% to 75%, stenosis length from 4 mm to 16 mm, and at 4 locations separately). Through numerical simulations, it was found that FFRCT decreased (from 0.89 to 0.74), when DS increased (from 45% to 75%). Similarly, FFRCT decreased with the increase of stenosis length and the stenosis located at proximal position had lower FFRCT than that at distal position. These findings are consistent with clinical observations. Applying the same method on two patients' CTA images yielded FFRCT close to the FFR values obtained via invasive angiography. The proposed noninvasive computation of FFRCT is promising for clinical diagnosis of CAD.Item Optimism and cardiovascular health: Longitudinal findings from the CARDIA Study(Wolters Kluwer, 2020) Boehm, Julia K.; Qureshi, Farah; Chen, Ying; Soo, Jackie; Umukoro, Peter; Hernandez, Rosalba; Lloyd-Jones, Donald; Kubzansky, Laura D.; Medicine, School of MedicineObjective: Favorable cardiovascular health is associated with greater longevity free of cardiovascular disease. Although the prevalence of cardiovascular health decreases with age, less is known about protective factors that promote and preserve it over time. We investigated whether optimism was associated with better cardiovascular health over a 10-year period. Methods: Participants included 3188 Black and White men and women from the Coronary Artery Risk Development in Young Adults study. Self-reported optimism was assessed in 2000 (this study's baseline) with the revised Life Orientation Test. Favorable cardiovascular health was defined by healthy status on five components of cardiovascular functioning that were repeatedly assessed through 2010 either clinically or via self-report (blood pressure, lipids, body mass index, diabetes, and smoking status). Linear mixed-effects models examined whether optimism predicted cardiovascular health over time, adjusting for covariates such as sociodemographic characteristics, health behaviors, health status, and depression diagnosis. Results: In models adjusting for sociodemographic characteristics, optimism was associated with better cardiovascular health across all time points (β = 0.08, 95% confidence interval = 0.04-0.11, p ≤ .001) but not with rate of change in cardiovascular health. Findings were similar when adjusting for additional covariates. Optimism did not interact significantly with race (p = .85) but did with sex, such that associations seemed stronger for women than for men (p = .03). Conclusions: Optimism may contribute to establishing future patterns of cardiovascular health in adulthood, but other factors may be more strongly related to how slowly or quickly cardiovascular health deteriorates over time.Item Regulation of Coronary Blood Flow(Wiley, 2017-03-16) Goodwill, Adam G.; Dick, Gregory M.; Kiel, Alexander M.; Tune, Johnathan D.; Cellular and Integrative Physiology, School of MedicineThe heart is uniquely responsible for providing its own blood supply through the coronary circulation. Regulation of coronary blood flow is quite complex and, after over 100 years of dedicated research, is understood to be dictated through multiple mechanisms that include extravascular compressive forces (tissue pressure), coronary perfusion pressure, myogenic, local metabolic, endothelial as well as neural and hormonal influences. While each of these determinants can have profound influence over myocardial perfusion, largely through effects on end-effector ion channels, these mechanisms collectively modulate coronary vascular resistance and act to ensure that the myocardial requirements for oxygen and substrates are adequately provided by the coronary circulation. The purpose of this series of Comprehensive Physiology is to highlight current knowledge regarding the physiologic regulation of coronary blood flow, with emphasis on functional anatomy and the interplay between the physical and biological determinants of myocardial oxygen delivery. © 2017 American Physiological Society. Compr Physiol 7:321-382, 2017.