Chest veins are actually superficial veins in the chest that are exposed, and most of them are normal physiological conditions. If the skin tension on the chest is relatively high, such as during breastfeeding and intense deep breathing or chest breathing, the superficial veins will be revealed and the veins will be visible. There are also a small number of patients who have bruising in the chest due to deep vein blockage or the presence of arteriovenous fistulas that lead to the establishment of superficial venous tortuous dilatation and collateral circulation. This requires an examination and a specialist to determine whether there is a blockage of the deep veins or an arteriovenous fistula. This is common in patients with superior vena cava obstruction syndrome or chronic renal failure on long-term dialysis, but in this case the majority of patients have clinical symptoms other than bruising of the chest. Therefore, in clinical practice, if bruising of the chest is present, it is important to go to a specialized vascular surgery department for systematic consultation and treatment.