Levo-Transposition of the great arteries accompanying defect(s). If a right-to-left or bidirectional shunt is present, the list of symptoms may include mild cyanosis. In a normal heart, oxygen-depleted ("deoxygenated") blood is pumped from the right atrium into the right ventricle, then through the pulmonary artery to the lungs where it is oxygenated. The oxygen-rich ("oxygenated") blood then returns, via the pulmonary veins, to the left atrium from which it is pumped into the left ventricle, then through the aorta to the rest of the body, including the heart muscle itself. With l-TGA, deoxygenated blood is pumped from the right atrium into the morphological left ventricle
Vein vs. systemic, and large vs. small. Most veins are equipped with valves to prevent blood flowing in the reverse direction. Veins are translucent, so the color a vein appears from an organism's exterior is determined in large part by the color of venous blood, which is usually dark red as a result of its low oxygen content. Veins appear blue because the subcutaneous fat absorbs low-frequency light, permitting only the highly energetic blue wavelengths to penetrate through to the dark vein and reflect back to the viewer. The colour of a vein can be affected by the characteristics of a