Chambers and valves of the heart. A typical heart has two upper and two lower chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump blood out of the heart. The heart valves, which keep blood flowing in the right direction, are gates at the chamber.

Your four heart valves are: Tricuspid: Lets oxygen-poor blood flow from your right atrium (upper chamber) to your right ventricle (lower chamber). Pulmonary: Lets oxygen-poor blood move from your right ventricle (lower chamber) to your pulmonary artery, which takes blood to your lungs to get oxygen.