What is a Cardiac PET?
A cardiac positron emission tomography (PET) scans the pictures of the heart muscle using a negligible level of radioactivity. Cardiac PET/CT results in improved accuracy, less radiation, and higher efficiency than the current model of nuclear stress testing (SPECT) in the diagnosis of coronary artery disease. Cardiac PET/CT is mainly helpful for patients with a high body mass index or BMI or dense breast/chest wall tissue, breast implants, or pleural or pericardial effusions.
What are some frequent uses of the procedure?
The cardiac PET is recommended for patients suffering from troubled heart conditions like an irregular heartbeat (arrhythmia), chest pain, chest tightness, trouble in breathing, weakness, and profuse sweating. Patients who may benefit from PET are those at high risk for major cardiac events and require more accurate identification of multivessel CAD, especially when planning for coronary artery revascularization. Relative visual understanding with SPECT may underestimate the existence and degree of the disease in question. The additional quantitative assessment of myocardial blood flow with complete hyperemia and flow reserve with PET enhances the diagnostic accuracy for detecting single or multi-vessel CAD with its vigorous attenuation correction algorithm. It also gives an incremental prognostic value to visual or semi-quantitative regional radiotracer uptake assessment with SPECT.
How should I prepare?
- Only drink a small amount of water as needed to take essential medicines before the test.
- Maintain a state of absolute fasting at least 4 hours before the test.
- Avoid all caffeine products, including coffee, tea, soft/energy drinks, cocoa, strawberries, chocolate, etc., for 24 hours.
- Avoid Medications having caffeine (such as Excedrin®, Anacin®, Nodoz®, diet pills) for 24 hours.
- Avoid smoking or using nicotine gum.
- The following medicines are also to be avoided 48 hours before the test.
- Isosorbide dinitrate (Dilatrate®, Isordil®)
- Isosorbide mononitrate (Imdur®, ISMO®, Monoket®)
- Nitroglycerin (Minitran®, Nitro Patches®, Nitrostat®)
- Dipyridamole (Persantine ®).
- Tell your physician if you have the following medical conditions and take the specified medications:
- Diabetes on insulin
- Cardiac PET and CT scans should be avoided in pregnant women, nursing mothers, and people suffering from acute medical conditions on recent treatment.
How does the procedure work?
A Cardiac PET is an imaging test that utilizes specialized dye to let the doctor view and examine the heart problems and symptoms. The stain is composed of some radioactive tracers, highlighting the affected or suspected heart areas. A cardiac PET/CT myocardial perfusion scan provides a pictorial presentation of the blood flow to the heart muscle, both at rest and under stress. It can also detect preliminary coronary artery disease by demonstrating decreased blood flow, which may benefit from angioplasty or surgery.
How is the procedure performed?
The patient sits on the chair, and his arm is inserted with an IV. Through the IV, the dye is injected into the veins. It takes around an hour for the veins to absorb the tracers in the stain. Meanwhile, the electrodes for the ECG are attached to the patient’s chest to monitor his heart rate.
Then, the patient goes under the scan process, lying on the narrow table linked to the PET machine. The table crawls inside the machine while the pictures are taken inside. Once the technician receives clear images, the table is taken out of the device. The electrodes are removed, and the test is done.
What will I experience during and after the procedure?
The injected dye may result in a headache or a warm, flushing sensation. Patients are advised to report any symptoms associated with chest, arm, or jaw pain and discomfort. Symptoms such as breathlessness, lightheadedness, and dizziness must also be immediately reported. This scan does not leave any significant radioactivity within the body after its completion. Regular activities can be resumed shortly after the exam.