{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1363670318748577792.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1161/01.cir.77.2.478"}},{"identifier":{"@type":"URI","@value":"https://www.ahajournals.org/doi/pdf/10.1161/01.CIR.77.2.478"}}],"dc:title":[{"@value":"Influence of heart rate, preload, afterload, and inotropic state on myocardial ultrasonic backscatter."}],"description":[{"type":"abstract","notation":[{"@value":"<jats:p>Ultrasonic backscatter is substantially modified by pathologic changes in myocardium. Influence of physiologic changes in heart rate, mean arterial pressure, preload, and inotropic state were studied in 17 anesthetized open-chest dogs. Heart rate was changed with atrial pacing/ULFS'49 (a selective bradycardiac agent). Mean arterial pressure was varied with aortic constriction/nitroprusside, preload was altered with nitroglycerin/volume infusion, and inotropic states were altered with dobutamine (10 microns/kg)/esmolol (100 microns/kg). IBR5, an optimum weighted frequency average (4 to 6.8 MHz) of the squared envelope of diffraction corrected for absolute backscatter, and the Fourier coefficient of amplitude modulation (FAM), an index of cardiac cycle-dependent variation, were measured from six sequential electrocardiographically gated intervals throughout the cardiac cycle. Heart rate, mean arterial pressure, preload, and inotropic state did not significantly affect IBR5. FAM increased from 3.5 +/- 0.3 dB (mean +/- SEM) to 7.0 +/- 0.4 dB (p less than .01) at a heart rate of 120 beats/min, and decreased to 3.9 +/- 0.4 at a heart rate of 160 beats/min. No change in FAM was noted with a rise (70 +/- 12 to 45 +/- 10 mmHg) in mean arterial pressure or preload (an increase or decrease in diastolic segment length of +/- 10% from the baseline). Dobutamine produced a significant increase in left ventricular dP/dt (2600 +/- 200 to 3475 +/- 275 mm Hg) and FAM (3.4 +/- 0.1 to 6.4; p less than .01). Esmolol significantly reduced left ventricular dP/dt (2600 +/- 200 to 2000 +/- 175 mm Hg, p less than .05) and FAM (3.4 +/- 0.01 to 6.4 +/- 0.1; p less than .01). We conclude that IBR5 is independent of heart rate, mean arterial pressure, preload, and inotropic state. Cardiac cycle-dependent amplitude modulation follows changes in cardiac contraction.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1383670318748577794","@type":"Researcher","foaf:name":[{"@value":"K B Sagar"}],"jpcoar:affiliationName":[{"@value":"Department of Medicine, Medical College of Wisconsin, Milwaukee 53226."}]},{"@id":"https://cir.nii.ac.jp/crid/1383670318748577921","@type":"Researcher","foaf:name":[{"@value":"L E Pelc"}],"jpcoar:affiliationName":[{"@value":"Department of Medicine, Medical College of Wisconsin, Milwaukee 53226."}]},{"@id":"https://cir.nii.ac.jp/crid/1383670318748577792","@type":"Researcher","foaf:name":[{"@value":"T L Rhyne"}],"jpcoar:affiliationName":[{"@value":"Department of Medicine, Medical College of Wisconsin, Milwaukee 53226."}]},{"@id":"https://cir.nii.ac.jp/crid/1383670318748577920","@type":"Researcher","foaf:name":[{"@value":"L S Wann"}],"jpcoar:affiliationName":[{"@value":"Department of Medicine, Medical College of Wisconsin, Milwaukee 53226."}]},{"@id":"https://cir.nii.ac.jp/crid/1383670318748577793","@type":"Researcher","foaf:name":[{"@value":"D C Waltier"}],"jpcoar:affiliationName":[{"@value":"Department of Medicine, Medical College of Wisconsin, Milwaukee 53226."}]}],"publication":{"publicationIdentifier":[{"@type":"PISSN","@value":"00097322"},{"@type":"EISSN","@value":"15244539"},{"@type":"PISSN","@value":"http://id.crossref.org/issn/00097322"}],"prism:publicationName":[{"@value":"Circulation"}],"dc:publisher":[{"@value":"Ovid Technologies (Wolters Kluwer Health)"}],"prism:publicationDate":"1988-02","prism:volume":"77","prism:number":"2","prism:startingPage":"478","prism:endingPage":"483"},"reviewed":"false","url":[{"@id":"https://www.ahajournals.org/doi/pdf/10.1161/01.CIR.77.2.478"}],"createdAt":"2011-06-17","modifiedAt":"2024-05-12","relatedProduct":[{"@id":"https://cir.nii.ac.jp/crid/1390001205037924352","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"<b>Dipyridamole Stress Echocardiography and Ultrasonic Myocardial Tissue Characterization in Predicting Myocardial Ischemia, in Comparison With Dipyridamole Stress Tc-99m MIBI SPECT Myocardial Imaging</b>"}]},{"@id":"https://cir.nii.ac.jp/crid/1390001205105033600","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Early Detection of Doxorubicin-Induced Myocardial Damage by Ultrasound Tissue Characterization With Integrated Backscatter"}]},{"@id":"https://cir.nii.ac.jp/crid/1390282680078593920","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Prediction of Functional Recovery of the Left Ventricle After Coronary Revascularization in Patients With Prior Anterior Myocardial Infarction. A Myocardial Integrated Backscatter Study."}]},{"@id":"https://cir.nii.ac.jp/crid/1390282680082550144","@type":"Article","resourceType":"学術雑誌論文(journal article)","relationType":["isReferencedBy"],"jpcoar:relatedTitle":[{"@language":"en","@value":"Ultrasonic Myocardial Tissue Characterization in Patients With Hypertrophic Cardiomyopathy and Pressure-Overloaded Hypertrophy by Backscattered Energy Temporal Analysis."}]}],"dataSourceIdentifier":[{"@type":"CROSSREF","@value":"10.1161/01.cir.77.2.478"},{"@type":"CROSSREF","@value":"10.1536/jhj.45.937_references_DOI_1EJYOOxMP9WyBp25AGHXKz3UATy"},{"@type":"CROSSREF","@value":"10.1253/circj.66.729_references_DOI_1EJYOOxMP9WyBp25AGHXKz3UATy"},{"@type":"CROSSREF","@value":"10.1253/circj.66.897_references_DOI_1EJYOOxMP9WyBp25AGHXKz3UATy"},{"@type":"CROSSREF","@value":"10.1253/circj.67.929_references_DOI_1EJYOOxMP9WyBp25AGHXKz3UATy"}]}