I-123 labeled hexadecenoic acid in comparison with Thallium-201 for myocardial imaging in coronary heart disease. A preliminary study.

The imaging properties of 123I-16-iodo-9-hexadecenoic acid (123I-HA), a terminally iodinated 17-carbon atom fatty acid analogue, were compared with Thallium-201 (201Tl). Because of its shorter half-life, favourable photon-energy and rapid myocardial turnover rate, 123I-HA possesses potential advantages in the study of regional myocardial perfusion and metabolism. Twelve patients with documented coronary artery disease (CAD) were studied; eight patients sustained an acute myocardial infarction, four patients suffered from unstable angina. Visually assessed, a similar distribution pattern and comparable imaging quality was demonstrated with both radionuclides. The scintigraphic results were also correlated with coronary arteriographic findings. A good relationship was found between the perfusion defects and the location of the coronary artery lesions in the patients with acute myocardial infarction. We conclude that 123I-HA is comparable to 201Tl in detecting areas of reduced myocardial perfusion in patients with CAD with the advantage of studying myocardial metabolism.