Collateral Arteries are new artery structures (which includes blood vessels and smaller capillaries) that are grown as a result of pushing your heart into a zone beyond where it is getting adequate blood supply during exercise.
These new “remodeled branches” – the medical term for them – seem to be more common in people with existing coronary artery disease. These vessels provide an alternative source of blood supply to the myocardium in cases of coronary artery disease or an acute (sudden) event such as a heart attack (where blood flow to heart muscle is stopped). Increasing evidence indicates that collateral arteries provide a relevant protective role in patients with coronary artery disease.
Harvard Medical School has released studies showing that patients with CAD should focus on the development of collateral arteries as a means of reducing the negative health effects of CAD and additionally minimize the chance of permanent heart damage in patients who experience a heart attack.