Thallium 201 kinetics in stunned myocardium characterized by severe postischemic systolic dysfunction

Journal Article · Tue May 01 00:00:00 EDT 1990 · Circulation; (USA)

DOI:https://doi.org/10.1161/01.CIR.81.5.1622· OSTI ID:6809539

Moore, C A; Cannon, J; Watson, D D; Kaul, S; Beller, G A ^[1]

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1. Univ. of Virginia Health Sciences Center, Charlottesville (USA)

The hypothesis tested in this study was that despite the presence of severe postischemic myocardial dysfunction (stunning), the extraction and subsequent intracellular washout of thallium 201 should be preserved as long as irreversible sarcolemmal membrane injury was avoided. To produce myocardial stunning, 19 open-chested dogs with a critical left anterior descending coronary artery (LAD) stenosis underwent 10 5-minute periods of total LAD occlusion, each interspersed by 10 minutes of reperfusion by reflow through the critical stenosis. In another 12 control dogs observed for the same time period, no LAD occlusions were performed after placement of the critical stenosis. Hemodynamics, regional myocardial thickening by quantitative two-dimensional echocardiography, and microsphere-determined regional blood flows were serially measured. In 18 stunned dogs, systolic thickening in the LAD zone was markedly reduced to 0.4 +/- 2.4% at 40 minutes after the 10th reperfusion period compared with 32.5 +/- 2.2% thickening (p less than 0.001) in 12 control dogs at a matched time. The 201Tl first-pass extraction fraction determined by a double-isotope method using intracoronary 201Tl administration was comparable after the 10th reflow in a subgroup of 13 stunned (0.78) and six control (0.79) dogs. The T1/2 for the intracellular washout rate was also not significantly different in another group of six stunned (60 +/- 13 minutes) and six control (53 +/- 14 minutes) dogs, nor was the percentage of the 201Tl dose initially distributed in the interstitial compartment (11 +/- 3% vs. 7 +/- 2%). Systemic hemodynamics and regional flows were comparable in the two groups at 40 minutes after the 10th reflow. No dog had evidence of myocardial necrosis by triphenyl tetrazolium chloride staining.

• OSTI ID: 6809539
• Journal Information: Circulation; (USA), Journal Name: Circulation; (USA) Vol. 81:5; ISSN 0009-7322; ISSN CIRCA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
ARTERIES
BETA DECAY RADIOISOTOPES
BLOOD FLOW
BLOOD VESSELS
BODY
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CORONARIES
DAYS LIVING RADIOISOTOPES
DIAGNOSIS
DIAGRAMS
DISEASES
DOGS
ELECTROCARDIOGRAMS
ELECTRON CAPTURE RADIOISOTOPES
HEART
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MUSCLES
MYOCARDIUM
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
THALLIUM 201
THALLIUM ISOTOPES
VERTEBRATES