The internal thoracic artery (ITA), formerly referred to as the internal mammary artery, is a vital blood vessel that provides circulation to the front of the chest wall and breast tissue. This artery exists in pairs, with one running on each side of the breastbone. At its termination point, the ITA splits into two branches: the superior epigastric and musculophrenic arteries.

In the field of cardiac surgery, the ITA is highly valued for coronary artery bypass grafting procedures. Particularly, the left ITA has demonstrated superior long-term patency compared to other graft options, including saphenous vein grafts and alternative arterial conduits such as the radial or gastroepiploic arteries. This makes it the preferred choice for revascularizing the left anterior descending coronary artery, which is often considered the most clinically significant vessel to treat in bypass surgery.