To evaluate this, the investigators are planning to examine patients who are scheduled for a clinically indicated myocardial scintigraphy. These examinations are routinely done by the Department of Nuclear Medicine in either a 1-day or a 2-day protocol according to the diagnostic reference values of the Federal Department for Radiological Protection. Blood samples will be taken from these patients at predefined time steps before and after the examination and DNA double-strand breaks will be determined from these blood samples specifically considering the applied activity of the tracer and the exposition kinetics.