Calculation of viable and infarcted myocardial mass from thallium-201 tomograms.

The feasibility of determining the mass of both viable and infarcted myocardium from tomographic images of thallium-201 distribution in the heart was studied in two normal dogs and ten dogs with acute infarction. Twenty-four hours after occlusion, thallium-201 was injected and 10 min later the hearts were removed and transaxial emission computed tomograms were obtained. Using the computer, an operator defined the epi- and endocardial surfaces of the left ventricle and the area of infarction in each tomogram.

Myocardial infarct quantification in the dog by single photon emission computed tomography.

Radionuclide techniques for sizing acute myocardial infarction have been hampered by the intrinsic limitations of the scintillation camera. Emission computed tomography can overcome these limitations. Single photon emission computed tomograms of the distribution of technetium-99m pyrophosphate in acute anterior and posterior infarcts were obtained in 16 dogs after death.

Myocardial imaging using emission computed tomography.

Single-photon emission computed tomography (ECT) was evaluated during myocardial studies in dogs. Acute anterior and posterior infarcts were imaged following injection of 99mTc-pyrophosphate or 201Tl. In most cases, tomographic delineation of infarct location and extent correlated with tissue section.