This Nuclear Medicine scan is a means of assessing the heart’s pumping ability. It allows an accurate means of measuring how efficiently the ventricles of the heart are contracting. The scan also may indicate the presence of underlying diseases such as cardiomyopathy or coronary artery disease. This scan is also used to assess heart function in cancer patients who are receiving powerful chemotherapy that may potentially have an adverse effect on the heart. By measurement of what is called the left ventricular ejection fraction, the oncologist or haematologist can better estimate the optimal chemotherapy dose for the patient, and by repeating the scan over the course of treatment can estimate the patient’s tolerance of the drug within safe levels.