Myocardial imaging with I-123 phenylpentadecanoic acid in normal volunteers

Uptake and washout (Δ%) of I-123 phenylpentadecanoic acid (IPPA) was studied at rest and following exercise in normal volunteers. I-123 PPA (3-8 mCi) was injected at rest in 6 and at peak exercise in 7 individuals. Gamma camera images were obtained for 60 minutes postinjection (p.i.). Blood samples were analyzed for free I/sup -/ and lipid soluble activity (Bligh and Dyer). Myocardial washout rates and plasma lipid soluble (CHCl/sub 3/) activity were calculated and are presented in this paper. Total blood activity remained unchanged from 10-60 min p.i. and free iodide in plasma was <10% at all times. Heart/lung and heart/liver ratios were also reported observations. The distribution and washout of radioactivity was uniform throughout the myocardium. No adverse reactions were noted in any of the volunteers. This study indicates excellent myocardial images can be obtained from 4 to 40 min. following the injection of IPPA at rest and peak exercise. IPPA may be useful for studying patients with heart disease