Interrupted aortic arch is a birth defect where the aorta is completely split, so blood to the lower body must detour through a small vessel that soon closes. Symptoms start in the first days of life and snowball fast. Gray or blue color is the first clue. Babies look ashen, especially the lower half, and lips can turn dusky when they cry. Fast, labored breathing is constant. The infant uses more breaths per minute and may grunt with each exhale. Weak or absent pulses show up in the legs. You can feel a good pulse in the arm, but the... Learn more