Gastric varicose veins. Gastroscope (endoscope) view of widened (varicose) veins in the stomach of a 69 year-old woman. The appearance of the veins (gastric varices) is caused by high blood pressure, and can signify a number of conditions. In this case the endoscope showed no varices in the oesophagus (gullet), and the patient was diagnosed with splenic vein thrombosis, a blockage of the vein formed from smaller veins from the stomach and spleen. Treatment may involve anti- clotting drugs or surgery to reduce the pressure on the vein.