SPECT Myocardial Perfusion Imaging
What is SPECT myocardial perfusion imaging?
SPECT Myocardial Perfusion Imaging is a valuable diagnostic tool used to evaluate coronary artery disease, especially for patients who cannot undergo traditional treadmill stress tests. This non-invasive procedure combines a chemical stress test with advanced imaging technology to provide detailed, three-dimensional images of the heart’s blood supply. It helps cardiologists identify areas of reduced blood flow, which can indicate coronary artery disease.
People with arthritis, back pain, or other heart or circulatory issues may struggle to walk on a treadmill or reach the target heart rate. In these cases, we use a nuclear imaging study to evaluate suspected coronary artery disease. The study involves giving medications like regadenoson, which temporarily dilate the coronary arteries for a few minutes.
We combine this “chemical stress test” with a low dose of radioactive isotope Tc99m. The nuclear camera detects this isotope and creates a three-dimensional image of the heart’s blood supply. This process is similar to CT scanning and is known as single photon emission computed tomography (SPECT) imaging.
How SPECT Imaging Works
If a person cannot reach the target heart rate through exercise, we perform a chemical stress test. We administer regadenoson to temporarily dilate the coronary arteries, mimicking the effects of physical exertion. This helps assess how the heart performs under stress.
We also inject a low-dose radioactive isotope (usually Tc99m) into the bloodstream. The nuclear camera detects the isotope and creates detailed, three-dimensional images of blood flow to the heart muscle. These images help identify areas of the heart that may not receive enough blood, which could indicate coronary artery disease (CAD).
Benefits of SPECT Myocardial Perfusion Imaging
- Non-Invasive: SPECT imaging does not require surgery or invasive techniques. It provides highly accurate information.
- High Diagnostic Accuracy: Combining the electrocardiogram, chemical stress test, and SPECT imaging improves the accuracy of diagnosing significant coronary artery disease (80-90%).
- Precise Visualization: The imaging provides detailed, three-dimensional images, allowing cardiologists to pinpoint areas with reduced blood flow and assess the severity of the disease.
What to Expect During SPECT Imaging
The procedure is safe and typically takes 30 to 60 minutes. First, the patient receives the radioactive isotope injection, followed by medication to induce temporary stress on the heart. We then take multiple images before and after the stress phase to provide a comprehensive view of heart function at rest and under stress.
SPECT myocardial perfusion imaging is essential for diagnosing coronary artery disease, especially in patients unable to undergo traditional treadmill tests. At RCA, we use this advanced imaging technique to provide accurate diagnoses, which guide the treatment and management of heart disease.
