The chest X-ray is less useful for heart disease diagnosis now that echocardiography is available. However it is still useful to show the lungs, since they may give a clue to respiratory causes of breathlessness e.g. COPD or pleural effusions. It may also show calcium in the valves or pericardium (the lining around the heart).

A chest X-ray is usually done before valve surgery because it can inform the surgeon about the structure of the chest and may occasionally detect unexpected abnormalities like cancers or old TB. More recently, some surgeons have preferred a CT scan of the chest to a chest X-Ray prior to surgery.