Cardiac catheterization or coronary angiography are invasive, diagnostic procedures that are performed to obtain information about the heart or its blood vessels. These procedures involve directing a catheter or catheters into the right and/or heart chambers and into the origin of the coronary arteries.
During cardiac catheterization the pressure and blood flow in the cardiac chambers are measured. Blood in these different chambers can also be collected to look for shunts or abnormal connections between chambers.  During coronary angiography contrast material is directly injected into the coronary arteries and the subsequent image recorded on x ray.
Cardiac catheterization is performed: HOW THE TEST IS PERFORMED    Abraham Salacata, MD, FACC