A cardiogram is bad for you. Nothing.

Cardiography is a common medical procedure used to assess the function and structure of the heart and vascular system. Although it is invasive, it is usually safe to perform under the guidance of a professional doctor.

Cardiography also carries potential risks, among which may be allergic reactions to iodinated contrast media. Iodinated contrast media are substances used to highlight blood vessels and heart structures, and some patients may be allergic to them, such as rashes, breathing difficulties, nausea, etc. Therefore, before performing a cardiography, your doctor will ask you if you are allergic to iodine and take appropriate precautions.