Effect of decreased blood flow and ischemia on myocardial thallium clearance
To determine the effect of reduced coronary blood flow on myocardial thallium-201 clearance over a range of flows, miniature radiation detectors were inserted into the left ventricular apex and positioned against the anterior and posterior endocardial walls in 21 dogs. Thallium was administered intravenously and myocardial tracer activity was monitored continuously for 1 hour in both walls. A balloon occluder was then partially inflated around the left anterior descending coronary artery in 19 dogs, producing a range of anterior wall blood flow reductions as assessed by the microsphere technique. Thallium activity was monitored continuously for 3 hours in both walls. Two dogs served as control animals and had no coronary artery occlusion at 1 hour. At the end of the 4 hour experiment, the dogs were sacrificed and the hearts counted in a well counter. The 19 dogs with coronary artery stenosis were divided into three groups (mild, moderate and severe flow reduction groups) on the basis of their poststenosis anterior/posterior wall regional myocardial blood flow ratios. The two control dogs had similar thallium clearances in the anterior and posterior left ventricular walls during the 3 hour period, as assessed by the radiation detectors, and by a final anterior/posterior wall thallium ratio near unity. All three groups of dogs with coronary stenosis had comparable fractional thallium clearances from the anterior and posterior walls before and after the balloon occluder inflation. The final anterior/posterior left ventricular wall thallium ratios were not significantly different than unity for all three groups of dogs.
- Research Organization:
- Massachusetts General Hospital, Boston
- OSTI ID:
- 6747102
- Journal Information:
- J. Am. Coll. Cardiol.; (United States), Journal Name: J. Am. Coll. Cardiol.; (United States) Vol. 3:3; ISSN JACCD
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL MODELS
BLOOD FLOW
BLOOD-PLASMA CLEARANCE
BODY
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CLEARANCE
DAYS LIVING RADIOISOTOPES
DISEASES
DOGS
ELECTRON CAPTURE RADIOISOTOPES
HEART
HEAVY NUCLEI
ISCHEMIA
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
MAMMALS
MICROSPHERES
MUSCLES
MYOCARDIUM
NUCLEI
ODD-EVEN NUCLEI
ORGANS
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
THALLIUM 201
THALLIUM ISOTOPES
VASCULAR DISEASES
VERTEBRATES