A chest CT can show some heart abnormalities. Chest CTs are not usually done to evaluate the heart. There are much better tests to look at the heart like echocardiograms (US of the heart), dedicated CTs of the heart and invasive coronary angiograms.
Why is chest CT limited for the heart?
CT scan of the chest is usually limited in evaluating the heart. We sometimes pickup abnormalities however. CT is not very good for evaluating the heart because CT shows just one picture in time. Often there is not enough detail because the slices are too thick. Also the heart is constantly pumping and moving which causes a fuzzy picture.
Can a chest CT show the coronary arteries?
A specialized CT test of the coronary arteries can show narrowing or blockages. A routine chest CT does not have enough detail. A coronary angiogram done by a cardiologist is more invasive but offers a detailed look at the coronaries and the opportunity for potential treatment.
What are some things chest CT picks up in the heart?
Fluid accumulation around the heart is called a pericardial effusion. This is easily detected on routine chest CTs. There are many causes for fluid accumulating around the heart like systemic inflammatory conditions, infections, cancer, treatment with radiation and kidney failure.
Chest CT will show enlargement of the heart or its chambers. Heart enlargement can occur from a variety of conditions like diseases of the valves, inflamed heart muscle (myocarditis), lung disease, cardiomyopathies that represent diseases of the heart muscle that impair function, and a variety of systemic diseases. We can not tell the exact cause most of the time in CT. We can report this so that further workup can be done.
CT of the chest can show masses of the heart. These are rare and are better detected with echocardiogram or ultrasound of the heart. A clot in one of the chambers can sometimes be identified as a darker spot or filling defect. This is important to identify as the clot can travel to other parts of the body.
What are the limitations of CT in evaluating the heart?
CT does not show us how the heart functions. Function of the heart is better evaluated with ultrasound or echocardiogram. CT does not show the valves between the cardiac chambers. CT does not show how well the heart is pumping since it’s one picture. Ultrasound can show how the heart is pumping since it takes many pictures continuously.
CT of the chest is rarely done to evaluate the heart. There are dedicated CT tests of the heart to look at the coronary arteries. They feed the blood to the heart. A blockage of one of the arteries can lead to heart attack. Echocardiograms or ultrasound of the heart can identify heart function, look at the valves and the wall. CT of the chest can pickup findings in the heart at times. These findings may need further evaluation with dedicated heart tests.