Clinical value of thallium 201 in a cardiology service

At present the most widely used element in isotopic cardiology is undoubtedly 201Tl. In the few years since its appearance many publication testify to its growing use in the external detection of coronary thrombosis, the discovery of ischemia exertion, the non-traumatic observation of patients after an aortocoronary bridging operation, the diagnosis of coronary deficiency associated with another heart disease (aorta narrowing, mitral prolapsus, obstructive cardiomyopathy) and in combination with two other radioisotopic methods. The present work is intended as a modest contribution, still very recent, to the critical study of this new technique in all its present aspects. Part one presents the various characteristics responsible for the advantages and limits of 201Tl, then describes the techniques and apparatus used. The production, dosimetry, toxicity and biological behaviour of 201Tl are also discussed. A hundred and twenty-five examinations were performed in the Nuclear Medicine Service of the Limoges UHC between May 1977 and October 1978. The results are analysed in part two. This is followed by a discussion which attempts, in the light of our experience, to situate the place occupied by 201Tl in the range of complementary examinations useful in declared or assumed coronary cases. We then propose an examination procedure and precise indications we believe to be justified, accounting for economic problems before considering the future prospects of myocardium scintigraphy