I'm a bit confused and concerned after my angiography. It didn't show any blockages, but they did notice some areas of narrowing. Now, they've recommended a thallium stress test. What kind of results can I expect from that? Also, why exactly is it needed when I've just had an angiography? How is it different from angiography?

The thallium stress test is used to evaluate blood flow to the heart muscle. It can help determine if there are any areas of the heart that are not receiving enough blood supply, which may indicate coronary artery disease. This test is especially useful when angiography shows no blockages but some narrowness in the arteries. During the thallium stress test, a small amount of radioactive thallium is injected into the bloodstream, and a special camera is used to take images of the heart at rest and after exercise. This helps to identify areas of the heart that may not be receiving enough blood flow, even if there are no significant blockages. The thallium stress test provides complementary information to angiography by focusing on blood flow to the heart muscle rather than just the anatomy of the coronary arteries. It can help to detect areas of reduced blood flow that may not be apparent on angiography alone. In summary, the thallium stress test can provide valuable information about blood flow to the heart muscle, especially in cases where angiography shows narrowness but no blockages.