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Cardiothoracic ratio

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Overview

The cardiothoracic ratio is the calculated by measuring the transverse diameter of the heart on a posterior / anterior chest X ray x-ray examination and dividing it by the diameter of the thoracic cage. A value > 0.5 or one half is consistent with enlargement of the heart or cardiomegaly.”[1]

Example Of An Enlarged Cardiothoracic Ratio

Example Of An Enlarged Cardiothoracic Ratio

Shown below is an example of an enlarged cardiothoracic ratio with a ratio exceeding 0.5:

References

References

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