While coronary angiography is generally a safe procedure, serious complications can occur in very rare cases. These include the formation of a tear (dissection) in the main artery (aorta) through which the catheter passes or at the entry point of a coronary artery. While aortic tears generally do not lead to serious consequences, tears at the mouth of a coronary artery can potentially result in a heart attack or death. Such risks are higher, especially in patients with severe coronary artery disease and those with significant narrowing in a major coronary artery. The overall likelihood of fatal complications during angiography is reported to be approximately one in a thousand (1/1000). However, considering the benefits and overall safety profile of the procedure, angiography is a very low-risk procedure.