Ischemic left ventricular dysfunction assessed on ECG-gated thallium-201 myocardial perfusion images.
Ischemic dysfunction of the left ventricle can be suggested by ancillary data derived from thallium-201 myocardial perfusion images. In this study, qualitative and quantitative assessments of global and segmental contraction derived from ECG-gated left anterior oblique images were analyzed to define more precisely transient ischemic hypokinesis. Immediate (4 mins post stress) and delayed (2 to 4 h) images were compared in 200 patients; 165 had coronary angiography and 35 had a low probability of coronary artery disease based on pretest and test outcome variables. For both immediate and delayed images, a quantitative index of left ventricular contraction (derived from the time-activity curve of the left ventricular cavity and validated in a previous study), correlated well with contrast ventriculography scores. The index derived from the immediate image also was related to the severity/extent of coronary artery lesions and to thallium-201 lung uptake. The ratio of indices (immediate/delayed) was depressed (P less than 0.001) in patients with two or three critically diseased vessels, and reflected the qualitative assessment of stress-induced dysfunction on cinematic images. These data suggest that the quantitative index derived from ECG-gated perfusion scans may be a valuable indicator of stress-induced ventricular contractile dysfunction.
Hurwitz
G A
GA
Department of Diagnostic Radiology/Nuclear Medicine, University of Western Ontario, London.
Laurin
N R
NR
Powe
J E
JE
Driedger
A A
AA
MacDonald
A C
AC
D003327:Coronary Disease / Q000000981:diagnostic imaging*; D015637:Gated Blood-Pool Imaging; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D009200:Myocardial Contraction / Q000502:physiology; D005082:Physical Exertion; D013318:Stroke Volume / Q000502:physiology*; D013794:Thallium Radioisotopes
D013794:Thallium Radioisotopes