4.3. Arteries That Travel Superiorly and Laterally
The diagram shows the three main branches of the aortic arch, although this time in more detail.
Now consider the subclavian artery on each side of the thorax. Beginning at the proximal part of each artery, the branches are:
1. Vertebral artery (going to supply the posterior lobe of the cerebrum)
2. Internal thoracic artery (supplying the anterior thoracic and abdominal walls)
3. Thyrocervical trunk (going to supply part of the thyroid gland and the neck)
4. Costocervical trunk (going to supply the first two intercostal spaces and the neck)
As you can see, the names of these arteries often tell what regions they supply or the path they take. So if you can't remember a specific name, have an educated guess!
Look at the diagram and note the presence of the left supreme/superior intercostal artery – it is a branch of the costocervical trunk. As mentioned above, this artery will supply the first two intercostal spaces (those between ribs 1 and 2, and ribs 2 and 3). This is an exception to the rule, because most of the posterior intercostal arteries arise directly from the descending aorta. The costocervical trunk provides an effective alternative blood supply.
If you've left exam revision a bit late, you might struggle to remember all of these details in one cramming session. Instead, focus on the basics, and knowing the basics well - make sure you can draw a quick sketch of the aortic arch and its three main branches, and note that the internal thoracic artery on each side comes off the subclavian artery.