My study materials use the word vesselcompression chamber of aorta to emphasize aorta's elastic property.
The arch of the aorta only coils, not its straight part. I think the reason why the arch coils is the elasticity of aorta (artery) is high. If the elasticity is too high, then the aorta is stiff. This means that heart has to work harder so higher systolic pressure and lower diastolic pressure.
Why does the arch of the aorta coils?