The case of a patient with severe dilative cardiomyopathy and cardiomegaly demonstrates that M-mode echocardiography and planar chest radiographs are not always sufficient to follow up the disease correctly. Using other non-invasive imaging modalities, in this case radionuclide ventriculography and NMR tomography, which provide more precise information with regard to morphology and function of both the right and the left heart, allows a more reliable follow-up of the disease.