Cardiac PET
Cardiac PET | |
---|---|
ICD-10-PCS | C23G, C23Y |
OPS-301 code | 3-741 |
Cardiac PET (or cardiac
Uses
Cardiac PET-CT scan can assess blood flow,
Radiopharmaceuticals
Rubidium-82 is produced from the decay of Strontium-82 through electron capture in a generator. It is used to access the blood vessels supplying the heart. Strontium-82 has a half-life of 25.5 days while Rubidium-82 has a half-life of 76 seconds. Heart muscles can take up Rubidium-82 efficiently through sodium–potassium pump. Compared with Technetium-99m, Rubidium-82 has higher uptake by the heart muscles. However, Rubidium-82 has lower uptake by heart muscles when compared to N-13 ammonia. But the positron energy emitted by Rubidium-82 is higher than N-13 ammonia and Fluorodeoxyglucose (18F). On the other hand, the positron range (the distance travelled by a positron from its production site until its annihilation with an electron) is longer when compared to other radiopharmaceuticals, causing reduced image resolution.[2]
Myocardium has higher uptake for N-13 ammonia when compared to Rubidium-82, thus useful for myocardial perfusion imaging. However, its half-life is only 9.96 minutes. Therefore, on-site facilities such as cyclotron and radiochemistry synthesis facilities should be available. There may be patchy uptake if the subject has defects in lateral ventricular wall. N-13 ammonia may occasionally be degraded by liver, thus causing reduced visibility of the inferior wall of the heart. N-13 ammonia uptake by the lungs is minimal.[2]
Indications
- Patients with many risk factors e.g. , high stress occupation, family history of heart attack
- Patients who are unable to exercise
- Patients suspected of heart attack
- Patients newly diagnosed with heart failure
- Patients with abnormal ECG or treadmill
Requirements
- Facility: taking into consideration clinical workflow, as well as regulatory requirements such as requisite shielding from radiation exposure
- Capital equipment: PET or PET/CT scanner
- Radiopharmaceutical: Rubidium-82 generator system or close access to cyclotron produced isotopes such as Nitrogen-13 ammonia
- Personnel: including specially trained physician, radiographers, radiation safety supervisors and optional nursing support
- Operations: stress test monitoring, as well as emergency response equipment, processing and review workstations, administrative and support personnel are additional considerations
References