Time course of thallium-201 redistribution after transient myocardial ischemia
The mechanism and time course of thallium-201 (/sup 201/Tl) redistribution after transient myocardial ischemia was investigated in 27 anesthetized dogs given 1.5 mCi of /sup 201/Tl intravenously 10 minutes after occlusion of the left anterior descending coronary artery. Coronary reperfusion (RP) was accomplished 10 minutes after /sup 201/Tl administration. Transmural myocardial biopsies were obtained in situ from normal (N) and ischemic (IS) regions during occlusion and 5 minutes (four dogs), 20 minutes (eight dogs), 90 minutes (six dogs), 4 hours (five dogs) and 6 hours (four dogs) after RP. There was a twofold rise in /sup 201/Tl activity (counts/10 min/mg) in the IS region after only 5 minutes of reflow with as yet no detectable change in /sup 201/Tl concentration in the N zone. In dogs undergoing 90 minutes of RP, /sup 201/Tl activity was 700 +- 150 (SEM) in the IS zone during occlusion and markedly increased (p < 0.001) to 3200 +- 100 at 90 minutes of reflow. During this period /sup 201/T1 activity in the N region decreased only slightly, from 7000 +- 800 to 6000 +- 450 (NS). In dogs that underwent 6 hours of RP, /sup 201/Tl activity in the IS zone increased from 1700 +- 500 during occlusion to 3300 +- 200 (p < 0.001) after RP. In this group, bbaTl activity in the N zone +- 1200 to 3900 +- 400 over the 6 hours of reflow, reflecting the magnitude of thallium washout after ischemia. This near-equalization of /sup 201/Tl activity between N and IS zones was already apparent by 4 hours of RP. These data indicate that /sup 201/Tl redistribution after transient myocardial ischemia is related to both delayed accumulation of /sup 201/Tl into ischemic myocardial segments and to a more rapid washout of the radionuclide from normal segments.
- Research Organization:
- Univ. of Virginia School of Medicine, Charlottesville
- OSTI ID:
- 6058004
- Journal Information:
- Circulation; (United States), Vol. 61:4
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ISCHEMIA
DIAGNOSIS
SCINTISCANNING
THALLIUM 201
DOGS
MYOCARDIUM
NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
COUNTING TECHNIQUES
DAYS LIVING RADIOISOTOPES
DIAGNOSTIC TECHNIQUES
DISEASES
ELECTRON CAPTURE RADIOISOTOPES
HEART
HEAVY NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MEDICINE
MUSCLES
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPE SCANNING
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
THALLIUM ISOTOPES
VASCULAR DISEASES
VERTEBRATES
550601* - Medicine- Unsealed Radionuclides in Diagnostics