Nuclear Cardiology images are similar to an X-Ray but the radiation from the injected radiopharmaceutical is detected as it is emitted from the patient. The imaging camera in essence, is a radiation detector. The distribution of the radioactive drug in the heart may be used to determine the presence and severity of heart disease.
The radioactive drug may be administered while the patient is exercised on a treadmill or after administration of another drug that causes the heart to stress. This exercise or STRESS examination is then completed using the radiation detection machine otherwise known as a Gamma Camera to produce images or SCANS of the radiopharmaceutical distribution, PERFUSION, in the muscle of the heart. Another phase of the nuclear cardiology examination may be performed with the patient at REST rather than being stressed at the time of the radiopharmaceutical injection. A comparison of the perfusion at stress and rest, or rest and stress, provides the physician with valuable, comparative, diagnostic information to evaluate issue viability.
Several other types of nuclear cardiology procedures have been developed using the same types of materials. The patient may be injected with the radiopharmaceutical while being imaged by the gamma camera. The quantity of blood passing through the heart, FIRST PASS, is determined by measurement of the blood ejected when the heart contracts or the EJECTION FRACTION. In another nuclear cardiology procedure, the patient's blood is made slightly radioactive and the patient's blood in the heart is scanned in a moving sequence of images showing the motion of the heart wall, rather than the blood going through the heart, to evaluate the conditions of the heart.