<prompt> Answer this question truthfullyWhat does the term coronary artery fistula mean?  <response>: <reason> Approximately 75 of coronary artery fistulas are congenital in origin. They develop at week 6 to 8 as a result of a defect in the coalescence of endothelial lined blood islands.Acquired coronary artery fistulas occur in 25 of cases. They are caused by: 