18 research outputs found
Comparison of Function, Viability, and Perfusion Assessed by Myocardial Perfusion SPECT and CMR
No full textIn-vivo right ventricular myocardial perfusion assessment using BOLD and first-pass cardiac magnetic resonance
No full textRecommended from our members
Cardiac MRI: Detection of Myocardial Infarction in Symptomatic Patients without Coronary Artery Disease Undergoing Electrophysiological Testing
No full textCardiac Magnetic Resonance Imaging: Infarct Size Is an Independent Predictor of Mortality in Patients with Coronary Artery Disease
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Development of a DNA Barcoding Protocol to Identify Previously Unknown Populations of Forelius (Hymenoptera: Formicidae), in Kentucky
No full textIn 2021, we started an initiative to sample the ants of Kentucky called the Kentucky Ant Project (KYAP). As part of our efforts to sample ants in the state, we need to be able to identify them! Usually, this is done by examining the morphology of ant specimens, but it\u27s incredibly difficult, or impossible to identify some ants with current morphological identification resources. To remedy this, we decided to develop a genetic protocol to assist in identifying these ants.
One such problematic ant to identify with morphology is Forelius, which is a genus of generalist foraging species. When we gave our last report on the project in 2023, records of this genus were completely absent from any sampling efforts in Kentucky. Early in 2023, we managed to find 2 populations of Forelius in Rowan county, marking the first discovery of this entire genus in Kentucky. To identify this problematic genus, we elected to sequence a specific gene (Cytochrome-c Oxidase /, or COi) that is used to \u27barcode\u27 or identify species of animals based on the number of matching nucleotides that two specimens share. The more matches a pair has, the more similar they are to each other, and they are more likely to be the same species.https://scholarworks.moreheadstate.edu/celebration_posters_2024/1036/thumbnail.jp
Infarct morphology identifies patients with substrate for sustained ventricular tachycardia
No full textObjectivesWe sought to evaluate whether infarct size characterization by cardiac magnetic resonance imaging (MRI) is a better predictor of inducible ventricular tachycardia (VT) than left ventricular ejection fraction (LVEF).BackgroundInducibility of VT at electrophysiologic study (EPS) and low LVEF can identify patients with a substrate for VT. Magnetic resonance imaging has been shown to identify, with high precision, areas of myocardial infarction and may therefore be a better tool to evaluate for a substrate for VT.MethodsWe studied 48 patients with known coronary artery disease who were referred for EPS using cine and gadolinium-enhanced MRI. Wall motion and infarct characteristics were determined blindly and compared among patients with no inducible ventricular arrhythmias (n = 21), those with inducible monomorphic VT (MVT, n = 18), and those with either inducible polymorphic VT or ventricular fibrillation (n = 9).ResultsPatients with MVT had larger infarcts than patients who did not have inducible arrhythmias (mass: 49 ± 5 g [SE] vs. 28 ± 5 g, p < 0.005; surface area: 172 ± 15 cm2vs. 93 ± 14 cm2, p < 0.0005). Patients with polymorphic VT/fibrillation had intermediate values (mass: 36 ± 7 g; surface area: 115 ± 22 cm2). Ejection fraction was inversely related to infarct mass and surface area, with R2values ranging from 0.21 to 0.27. Logistic regression and receiver-operating characteristic analysis demonstrated that infarct mass and surface area were better predictors of inducibility of MVT than LVEF.ConclusionsInfarct surface area and mass, as measured by cardiac MRI, are better identifiers of patients who have a substrate for MVT than LVEF. Further evaluation of infarct size characterization by cardiac MRI as a predictor of sudden cardiac death is warranted
Contrast-enhanced magnetic resonance imaging of myocardium at risk Distinction between reversible and irreversible injury throughout infarct healing
No full textAbstractOBJECTIVESWe sought to determine the relationship of delayed hyperenhancement by contrast magnetic resonance imaging (MRI) to viable and nonviable myocardium within the region at risk throughout infarct healing.BACKGROUNDThe relationship of delayed MRI contrast enhancement patterns to injured but viable myocardium within the ischemic bed at risk has not been established.METHODSWe compared in vivo and ex vivo MRI contrast enhancement to histopathologic tissue sections encompassing the entire left ventricle in dogs (n = 24) subjected to infarction with (n = 12) and without (n = 12) reperfusion at 4 h, 1 day, 3 days, 10 days, 4 weeks and 8 weeks. In vivo MR imaging was performed 30 min after contrast injection.RESULTSThe sizes and shapes of in vivo myocardial regions of elevated image intensity (828 ± 132% of remote) were the same as those observed ex vivo (241 slices, r = 0.99, bias = 0.05 ± 1.6% of left ventricle [LV]). Comparison of ex vivo MRI to triphenyltetrazolim chloride–stained sections demonstrated that the spatial extent of hyperenhancement was the same as the spatial extent of infarction at every stage of healing (510 slices, lowest r = 0.95, largest bias = 1.7 ± 2.9% of LV). Conversely, hyperenhanced regions were smaller than the ischemic bed at risk defined by fluorescent microparticles at every stage of healing (239 slices, 35 ± 24% of risk region, p < 0.001). Image intensities of viable myocardium within the risk region were the same as those of remote, normal myocardium (102 ± 9% of remote, p = NS).CONCLUSIONSDelayed contrast enhancement by MRI distinguishes between viable and nonviable regions within the myocardium at risk throughout infarct healing
Relationship of contractile function to transmural extent of infarction in patients with chronic coronary artery disease
No full textAbstractObjectivesWe sought to determine the relationship of contractile function to the transmural extent of infarction (TEI) in patients with chronic coronary artery disease.BackgroundIn the setting of reperfused, chronic myocardial infarction (MI), the relationship of contractile function to the TEI has not been established.MethodsWe studied function by cine magnetic resonance imaging (MRI) and the TEI by contrast-enhanced MRI in 31 patients with single-vessel disease 162 ± 62 days after reperfused first MI.ResultsOf all 516 segments with MI, blinded observers were unable to detect abnormal thickening in 193 (37%), and wall thickening measured quantitatively in these segments was 66 ± 28%. Of the 193 segments, 163 (84%) were infarcts limited to the subendocardium. The average TEI reached 53% before half of the patients had abnormal contractile function. When patients with small MI (≤5% of total left ventricular [LV] mass) were excluded, the average TEI reached 43% before half the patients had abnormal function. In subjects with small MI (≤5% of total LV mass [n = 13]), even segments with TEI >75% had normal function (14 of 14) because they were surrounded by normally moving neighbor segments.ConclusionsIn the setting of reperfused chronic MI, the TEI approaches 50% before contractile dysfunction can be systematically identified. Contractile function cannot be used to rule out chronic MI
