Blockage in which artery is likely involved when a patient has a complete heart block?
Answer: Right Coronary Artery in 70-80% of the population and left coronary artery in the rest.
“A branch off of the right coronary artery is responsible for the blood supply of the AV node in 70%-80% of the population. This is referred to as being “right dominant.” In the remaining portion of the population, the left coronary artery provides flow to the AV node. In complete heart block, there is no communication between the atrium and ventricle because of interruption of electrical flow through the AV node in the setting of acute ischemia to the node.”
Note:
The Sinoatrial node receives its blood supply from the right coronary artery in 55% of patients and left coronary artery in 45% of patients.