Thanks for your question.
An infarct is short for infarction, which is a medical term for tissue that has lost its blood supply and is no longer viable. If this occurs in the brain, it is a cerebral infarction, or stroke. In the heart, it is a myocardial (heart muscle) infarction, or heart attack. With time, this area undergoes changes that eventually lead to a scar.
When doctors talk about the heart as a pump, we usually are talking about the left ventricle which is the main pumping chamber. The right ventricle is not a very effective pump, and gains much of its function by piggy backing on the left ventricle.
The main areas of the left ventricle are the anterior wall (front of the heart), the posterior wall (back of the heart), the lateral wall (left side of the heart), and the inferior wall (the bottom of the heart). Different blood vessels supply each area, with the right coronary artery supplying blood to the inferior wall.
An inferior wall infarct is a myocardial infarction involving the bottom of the left ventricle, usually caused by a blockage within the right coronary artery.
I hope this has been helpful.
Martin Cane, M.D.