Table 2. Artificial blood vessels of different diameters.

	Artery diameter	Usage sites	Indications	Main challenges	Commercial materials
Large	> 8 mm	Aortoiliac arteries.	Open aortic aneurysm repair. Coarctation of the aorta.	Weak mechanical durability. Compliance mismatch. Aneurysmal-like dilation.	Non-degradable materials: PET, ePTFE
Medium	6-8 mm	Carotid artery. Femoral artery.	Similar to large	Similar to large	Similar to large
Small	< 6 mm	Coronary arteries. Infrainguinal arteries (below the inguinal ligament). Infrageniculate arteries (below the knee). Coronary artery bypass.	Arteriovenous shunts. Coronary artery bypass. Peripheral arterial occlusive disease.	Stenosis/occlusion caused by thrombosis or intimal hyperplasia. Low haemocompatibility.	Autologous vessels: ITA, SV

Note: ePTFE: expanded polytetrafluoroethylene; ITA: internal thoracic artery; PET: poly(ethylene terephthalate); SV: saphenous vein.