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22. Is anterior ST depression with acute transmural inferior infarction due to posterior infarction? A vectorcardiographic and scintigraphic study

Author

Mukharji, Jhulan, Murray, Suzanne, Lewis, Samuel E., Croft, Charles H., Corbett, James R., Willerson, James T., and Rude, Robert E.

Subjects
cardiovascular system, cardiovascular diseases
Abstract

The hypothesis that anterior ST segment depression represents concomitant posterior infarction was tested in 49 patients admitted with a first transmural inferior myocardial infarction. Anterior ST depression was defined as 0.1 mV or more ST depression in leads V1, V2or V3on an electrocardiogram recorded within 18 hours of infarction. Serial vectorcardiograms and technetium pyrophosphate scans were obtained. Eighty percent of the patients (39 of 49) had anterior ST depression. Of these 39 patients, 34% fulfilled vectorcardiographic criteria for posterior infarction, and 60% had pyrophosphate scanning evidence of posterior infarction. Early anterior ST depression was neither highly sensitive (84%) nor specific (20%) for the detection of posterior infarction as defined by pyrophosphate imaging. Of patients with persistent anterior ST depression (≥ 72 hours), 87% had posterior infarction detected by pyrophosphate scan. In patients with inferior myocardial infarction, vectorcardiographs evidence of posterior infarction correlated poorly with pyrophosphate imaging data. Right ventricular infarction was present on pyrophosphate imaging in 40% of patients with pyrophosphate changes of posterior infarction but without vectorcardiographic evidence of posterior infarction.It is concluded that: 1) the majority of patients with acute inferior myocardial infarction have anterior ST segment depression; 2) early anterior ST segment depression in such patients is not a specific marker for posterior infarction; and 3) standard vectorcardiographic criteria for transmural posterior infarction may be inaccurate in patients with concomitant transmural inferior myocardial infarction or right ventricular infarction, or both.

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23. Measurement of myocardial infarction fraction using single photon emission computed tomography

Author

Wolfe, Christopher L., Lewis, Samuel E., Corbett, James R., Parkey, Robert W., Buja, L. Maximilian, and Willerson, James T.

Abstract

Although infarct size correlates generally with prognosis after acute myocardial infarction, an absolute measure of infarct size may have differing prognostic significance depending on absolute left ventricular mass. To test the hypothesis that single photon emission computed tomography can accurately measure myocardial infarct size as a percent of total left ventricular mass (“infarction fraction”), thallium-201 and technetium-99m pyrophosphate tomograms were acquired in 21 dogs 24 to 48 hours after fixed occlusion of the left anterior descending or circumflex coronary artery. Pathologic infarct weight was measured as the myocardial mass that showed no staining with triphenyltetrazolium chloride. Scintigraphic infarct mass by technetium-99m pyrophosphate was calculated from the total number of left ventricular volume elements (voxels) demonstrating technetium-99m pyrophosphate uptake x voxel dimension ([0.476 cm]3) × specific gravity of myocardium (1.05 g/cm3). Scintigraphic left ventricular mass was calculated in a similar fashion using an overlay of the thallium-201 and technetium-99m pyrophosphate scans. The “infarction fraction” was calculated as: infarction fraction = infarct mass/left ventricular mass.

Published
1985
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25. Is anterior ST depression with acute transmural inferior infarction due to posterior infarction?

Author

Mukharji, Jhulan, Murray, Suzanne, Lewis, Samuel E., Croft, Charles H., Corbett, James R., Willerson, James T., and Rude, Robert E.

Abstract

The hypothesis that anterior ST segment depression represents concomitant posterior infarction was tested in 49 patients admitted with a first transmural inferior myocardial infarction. Anterior ST depression was defined as 0.1 mV or more ST depression in leads V1, V2or V3on an electrocardiogram recorded within 18 hours of infarction. Serial vectorcardiograms and technetium pyrophosphate scans were obtained. Eighty percent of the patients (39 of 49) had anterior ST depression. Of these 39 patients, 34% fulfilled vectorcardiographic criteria for posterior infarction, and 60% had pyrophosphate scanning evidence of posterior infarction. Early anterior ST depression was neither highly sensitive (84%) nor specific (20%) for the detection of posterior infarction as defined by pyrophosphate imaging. Of patients with persistent anterior ST depression (≥ 72 hours), 87% had posterior infarction detected by pyrophosphate scan. In patients with inferior myocardial infarction, vectorcardiographs evidence of posterior infarction correlated poorly with pyrophosphate imaging data. Right ventricular infarction was present on pyrophosphate imaging in 40% of patients with pyrophosphate changes of posterior infarction but without vectorcardiographic evidence of posterior infarction.

Published
1984
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26. Prospective Evaluation of Renal Allograft Dysfunction with 99mTechnetium-Diethylenetriaminepentaacetic Acid Renal Scans

Author

McConnell, John D., Sagalowsky, Arthur I., Lewis, Samuel E., Gailiunas, Peter, Helderman, J. Harold, Dawidson, Ingemar, and Peters, Paul C.

Abstract

A prospective, single-blinded study was done to determine the ability of serial 99mtechnetium-diethylenetriaminepentaacetic acid scans to diagnose renal allograft rejection. Among 28 transplant recipients 111 renal scans were obtained 1 day postoperatively and every 3 to 4 days thereafter for 3 weeks in all patients retaining an allograft. Computer-generated time-activity blood flow curves were analyzed semiquantitatively for the 1) interval between curve peaks of the allograft and iliac artery, 2) renal transit time and 3) renal washout of radionuclide. Excretory function was assessed by degree and interval to appearance of radionuclide in the calices and bladder. Deterioration of renal blood flow and excretion compared to the initial scan was considered rejection. Of 52 scans performed during clinical rejection 47 (90.4 per cent) were interpreted as showing rejection (sensitivity). Of 53 scans interpreted as showing rejection 47 (88.7 per cent) were positive for clinical rejection. The remaining 6 patients (initial false positive results) suffered clinical rejection within 24 to 72 hours. We conclude that 99mtechnetium-diethylenetriaminepentaacetic acid renal scans are useful in the differential diagnosis of renal allograft dysfunction.

Published
1984
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29. Early detection of left ventricular dysfunction in chronic aortic regurgitation as assessed by contrast angiography, echocardiography, and rest and exercise scintigraphy

Author

Huxley, Robert L, primary, Gaffney, F.Andrew, additional, Corbett, James R, additional, Firth, Brian G, additional, Peshock, Ronald, additional, Nicod, Pascal, additional, Rellas, James S, additional, Curry, George, additional, Lewis, Samuel E, additional, and Willerson, James T, additional

Published
1983
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34. Electrocardiographic, enzymatic and scintigraphic criteria of acute myocardial infarction as determined from study of 726 patients (a MILIS study)

Author

Turi, Zoltan G., primary, Rutherford, John D., additional, Roberts, Robert, additional, Muller, James E., additional, Jaffe, Allan S., additional, Rude, Robert E., additional, Parker, Corette, additional, Raabe, Daniel S., additional, Stone, Peter H., additional, Hartwell, Tyler D., additional, Lewis, Samuel E., additional, Parkey, Robert W., additional, Gold, Herman K., additional, Robertson, Thomas L., additional, Sobel, Burton E., additional, Willerson, James T., additional, and Braunwald, Eugene, additional

Published
1985
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37. Myocardial rupture after myocardial infarction

Author

Nicod, Pascal, primary, Corbett, James, additional, Leachman, Richard, additional, Croyle, Philip H., additional, Reich, Sanford, additional, Peshock, Ronald, additional, Farkas, Robert, additional, Rude, Robert, additional, Buja, L.Maximilian, additional, Mills, Lawrence, additional, Lewis, Samuel E., additional, and Willerson, James T., additional

Published
1982
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47. "Doughnut" Technetium Pyrophosphate Myocardial Scintigrams

Author

NICOD, PASCAL, primary, CORBETT, JAMES R., additional, RUDE, ROBERT E., additional, DEHMER, GREGORY J., additional, SMUCKER, MARK, additional, BUJA, L MAXIMILIAN, additional, PARKEY, ROBERT W., additional, LEWIS, SAMUEL E., additional, and WILLERSON, JAMES T., additional

Published
1982
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50. Iodine-123 phenylpentadecanoic acid: Detection of acute myocardial infarction and injury in dogs using an iodinated fatty acid and single-photon emission tomography

Author

Rellas, James S., primary, Corbett, James R., additional, Kulkarni, Padmakar, additional, Morgan, Chuck, additional, Devous, Michael D., additional, Buja, L.Maximilian, additional, Bush, Larry, additional, Parkey, Robert W., additional, Willerson, James T., additional, and Lewis, Samuel E., additional

Published
1983
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