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"What can a CT angiography show that an EKG cannot?"


Hi. I'm a 33 year old woman scheduled to have a CT angiography. What will this test show that an EKG will not?


An EKG is performed by placing several electrical leads on the chest wall and extremities. It is a painless and non-invasive procedure used to look at the electrical activity generated by the heart. This is an optimal way of determining the heart's rhythm and rate, and the pattern in which the heart utilizes this electricity.

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It can show signs of prior heart disease (based on abnormalities of the electrical patterns) or an active heart attack, and can suggest abnormalities in the size of the different chambers of the heart. A CT angiography is performed by using CT technology (several combined "slices" of x-rays used to generate an image) and contrast dye injected into a blood vessel. It is a relatively non-invasive method of getting a better look at the body's vessels. In the case of a CT-A focusing on the heart, the coronary arteries can be assessed. The path of the vessels around the heart can be seen, and to a degree, the buildup of calcium and cholesterol plaques within the arteries can be assessed. While a picture of the vessels can be generated, the CT-A does not reveal any information about the electrical patterns of the heart like the EKG does.

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