[Isotopes and idiopathic dilated cardiomyopathy].

Idiopathic dilated cardiomyopathy is a myocardial disease of unknown cause which carries a poor prognosis. Different isotopic techniques provide information about the factors which influence its development and about its severity and potential to progress. The results of isotopic right and left ventriculography are important in establishing the prognosis. Thallium 201 myocardial scintigraphy can show myocardial perfusion defects which are often multiple and widespread. The prognostic significance of these abnormalities has not been fully established. Gallium-67 myocardial scintigraphy may show inflammatory phenomena within the myocardium, orientating the diagnosis to myocarditis. MIBG scintigraphy assesses adrenergic presynaptic activity which, when decreased (heart/mediastinum uptake < 1.2), carries a very poor prognosis. Finally, anti-myosin antibody myocardial scintigraphy may show regions of acute or subacute cellular destruction which may be markers of myocardial toxicity of alcohol and have important prognostic implications in the medium term.