The Experts below are selected from a list of 1220604 Experts worldwide ranked by ideXlab platform

Otto Muzik - One of the best experts on this subject based on the ideXlab platform.

  • coronary diameter and vasodilator function in children following arterial switch operation for complete transposition of the great arteries
    American Journal of Cardiology, 2010
    Co-Authors: Daniel R. Turner, Nancy M Sullivan, Tajinder P Singh, Otto Muzik, Thomas J. Forbes
    Abstract:

    Coronary reimplantation during arterial switch operation (ASO) may affect coronary artery growth and function during childhood. The purpose of this study was to assess coronary artery diameter and regional myocardial blood flow (MBF) and myocardial flow reserve (MFR) in children after neonatal ASO. We measured proximal diameters of left anterior descending (LAD), left circumflex, and posterior descending coronary arteries on coronary angiogram in 12 children (median age 11 years, range 7.6 to 15.1) with a history of neonatal ASO. These children then underwent cardiac positron emission tomographic imaging using Nitrogen-13 ammonia to assess MBF at baseline and during intravenous adenosine hyperemia in regions supplied by these 3 coronary arteries. Coronary artery z-scores were within normal range (−2.0 to 2.0) for 32 of 36 coronary arteries. MFR (ratio of hyperemic to basal MBF) was normal (>2.5) in all myocardial regions in 10 of 12 patients. The remaining 2 patients, 1 with a dual LAD and 1 with LAD origin from the right coronary artery, had generalized impairment of hyperemic MBF (

  • assessment of myocardial perfusion by dynamic n 13 ammonia pet imaging comparison of 2 tracer kinetic models
    Journal of Nuclear Cardiology, 2005
    Co-Authors: Aliasghar Khorsand, Otto Muzik, Senta Graf, Christian Pirich, Kurt Kletter, Robert Dudczak, Gerald Maurer, Heinz Sochor, E Schuster, Gerold Porenta
    Abstract:

    Background Measurement of myocardial blood flow (MBF) by dynamic Nitrogen 13 ammonia (NH3) positron emission tomography (PET) uses tracer kinetic modeling to analyze time-activity curves. We compared 2 commonly used models with 2 compartments (2C) and 3 compartments (3C) for quantification of MBF and coronary flow reserve (CFR).

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Background Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies. Twenty-eight healthy volunteers underwent PET imaging at rest with either13N-ammonia (n=14),82Rb (n=8), or62Cu-PTSM (n=6). Eight subjects given13N-ammonia also underwent imaging after adenosine. Activity measured in the posterolateral wall on transaxial images was significantly lower than in the septum for13N-ammonia, both at rest (p<0.005) and after adenosine (p<0.05). No differences were detected for82Rb or62Cu-PTSM. The septum/posterolateral wall activity ratios for13N-ammonia,82Rb, and62Cu-PTSM were 1.15±0.07, 1.00±0.06, and 0.97±0.08, respectively (p<0.001). Regional analysis of image data showed the percent of maximal activity data for13N-ammonia in the lateral wall to be less than that of other regions (p<0.001) and in the inferior wall to be greater than in the anterior and lateral walls (p<0.001). For62Cu-PTSM, activity in the inferior wall was greater than that in other regions (p<0.005). No regional differences were detected for82Rb. The relatively increased wall activity with13N-ammonia and62Cu-PTSM is most likely due to cross-contamination of activity from the liver. The significant reduction in activity in the lateral wall with13N-ammonia, which persists after adenosine, is most likely related to regional heterogeneity in13N-ammonia retention and may reflect regional differences in metabolic-trapping mechanisms for13N-ammonia. Further investigation is required to elucidate the underlying mechanism of this phenomenon. Reduced tracer retention in the lateral wall segment as a normal variant must be considered when evaluating clinical13N-ammonia PET studies.

Markus Schwaiger - One of the best experts on this subject based on the ideXlab platform.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Background Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies. Twenty-eight healthy volunteers underwent PET imaging at rest with either13N-ammonia (n=14),82Rb (n=8), or62Cu-PTSM (n=6). Eight subjects given13N-ammonia also underwent imaging after adenosine. Activity measured in the posterolateral wall on transaxial images was significantly lower than in the septum for13N-ammonia, both at rest (p<0.005) and after adenosine (p<0.05). No differences were detected for82Rb or62Cu-PTSM. The septum/posterolateral wall activity ratios for13N-ammonia,82Rb, and62Cu-PTSM were 1.15±0.07, 1.00±0.06, and 0.97±0.08, respectively (p<0.001). Regional analysis of image data showed the percent of maximal activity data for13N-ammonia in the lateral wall to be less than that of other regions (p<0.001) and in the inferior wall to be greater than in the anterior and lateral walls (p<0.001). For62Cu-PTSM, activity in the inferior wall was greater than that in other regions (p<0.005). No regional differences were detected for82Rb. The relatively increased wall activity with13N-ammonia and62Cu-PTSM is most likely due to cross-contamination of activity from the liver. The significant reduction in activity in the lateral wall with13N-ammonia, which persists after adenosine, is most likely related to regional heterogeneity in13N-ammonia retention and may reflect regional differences in metabolic-trapping mechanisms for13N-ammonia. Further investigation is required to elucidate the underlying mechanism of this phenomenon. Reduced tracer retention in the lateral wall segment as a normal variant must be considered when evaluating clinical13N-ammonia PET studies.

Rob S. B. Beanlands - One of the best experts on this subject based on the ideXlab platform.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Background Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies. Twenty-eight healthy volunteers underwent PET imaging at rest with either13N-ammonia (n=14),82Rb (n=8), or62Cu-PTSM (n=6). Eight subjects given13N-ammonia also underwent imaging after adenosine. Activity measured in the posterolateral wall on transaxial images was significantly lower than in the septum for13N-ammonia, both at rest (p<0.005) and after adenosine (p<0.05). No differences were detected for82Rb or62Cu-PTSM. The septum/posterolateral wall activity ratios for13N-ammonia,82Rb, and62Cu-PTSM were 1.15±0.07, 1.00±0.06, and 0.97±0.08, respectively (p<0.001). Regional analysis of image data showed the percent of maximal activity data for13N-ammonia in the lateral wall to be less than that of other regions (p<0.001) and in the inferior wall to be greater than in the anterior and lateral walls (p<0.001). For62Cu-PTSM, activity in the inferior wall was greater than that in other regions (p<0.005). No regional differences were detected for82Rb. The relatively increased wall activity with13N-ammonia and62Cu-PTSM is most likely due to cross-contamination of activity from the liver. The significant reduction in activity in the lateral wall with13N-ammonia, which persists after adenosine, is most likely related to regional heterogeneity in13N-ammonia retention and may reflect regional differences in metabolic-trapping mechanisms for13N-ammonia. Further investigation is required to elucidate the underlying mechanism of this phenomenon. Reduced tracer retention in the lateral wall segment as a normal variant must be considered when evaluating clinical13N-ammonia PET studies.

Gary D Hutchins - One of the best experts on this subject based on the ideXlab platform.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Background Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies. Twenty-eight healthy volunteers underwent PET imaging at rest with either13N-ammonia (n=14),82Rb (n=8), or62Cu-PTSM (n=6). Eight subjects given13N-ammonia also underwent imaging after adenosine. Activity measured in the posterolateral wall on transaxial images was significantly lower than in the septum for13N-ammonia, both at rest (p<0.005) and after adenosine (p<0.05). No differences were detected for82Rb or62Cu-PTSM. The septum/posterolateral wall activity ratios for13N-ammonia,82Rb, and62Cu-PTSM were 1.15±0.07, 1.00±0.06, and 0.97±0.08, respectively (p<0.001). Regional analysis of image data showed the percent of maximal activity data for13N-ammonia in the lateral wall to be less than that of other regions (p<0.001) and in the inferior wall to be greater than in the anterior and lateral walls (p<0.001). For62Cu-PTSM, activity in the inferior wall was greater than that in other regions (p<0.005). No regional differences were detected for82Rb. The relatively increased wall activity with13N-ammonia and62Cu-PTSM is most likely due to cross-contamination of activity from the liver. The significant reduction in activity in the lateral wall with13N-ammonia, which persists after adenosine, is most likely related to regional heterogeneity in13N-ammonia retention and may reflect regional differences in metabolic-trapping mechanisms for13N-ammonia. Further investigation is required to elucidate the underlying mechanism of this phenomenon. Reduced tracer retention in the lateral wall segment as a normal variant must be considered when evaluating clinical13N-ammonia PET studies.

Edwin R. Wolfe - One of the best experts on this subject based on the ideXlab platform.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Background Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies.

  • heterogeneity of regional Nitrogen 13 labeled ammonia tracer distribution in the normal human heart comparison with rubidium 82 and copper 62 labeled ptsm
    Journal of Nuclear Cardiology, 1994
    Co-Authors: Rob S. B. Beanlands, Otto Muzik, Edwin R. Wolfe, Gary D Hutchins, Markus Schwaiger
    Abstract:

    Recent reports on13N-labeled ammonia (13N-ammonia) positron emission tomographic (PET) imaging have suggested a relative reduction of measured tracer activity in the posterolateral wall. Such inhomogeneity of tracer distribution could potentially affect accuracy for detection of disease. The aim of this study was to compare the regional distribution of13N-ammonia with82Rb and62Cu-labeled PTSM (62Cu-PTSM) to identify tracer-specific patterns that may be important in the clinical interpretation of cardiac flow studies. Twenty-eight healthy volunteers underwent PET imaging at rest with either13N-ammonia (n=14),82Rb (n=8), or62Cu-PTSM (n=6). Eight subjects given13N-ammonia also underwent imaging after adenosine. Activity measured in the posterolateral wall on transaxial images was significantly lower than in the septum for13N-ammonia, both at rest (p<0.005) and after adenosine (p<0.05). No differences were detected for82Rb or62Cu-PTSM. The septum/posterolateral wall activity ratios for13N-ammonia,82Rb, and62Cu-PTSM were 1.15±0.07, 1.00±0.06, and 0.97±0.08, respectively (p<0.001). Regional analysis of image data showed the percent of maximal activity data for13N-ammonia in the lateral wall to be less than that of other regions (p<0.001) and in the inferior wall to be greater than in the anterior and lateral walls (p<0.001). For62Cu-PTSM, activity in the inferior wall was greater than that in other regions (p<0.005). No regional differences were detected for82Rb. The relatively increased wall activity with13N-ammonia and62Cu-PTSM is most likely due to cross-contamination of activity from the liver. The significant reduction in activity in the lateral wall with13N-ammonia, which persists after adenosine, is most likely related to regional heterogeneity in13N-ammonia retention and may reflect regional differences in metabolic-trapping mechanisms for13N-ammonia. Further investigation is required to elucidate the underlying mechanism of this phenomenon. Reduced tracer retention in the lateral wall segment as a normal variant must be considered when evaluating clinical13N-ammonia PET studies.