الوقت المتطلب للقراءة 5 دقيقةWhat is meant by heart valve replacement surgery? The heart muscle consists of four chambers: two upper chambers, known as the right atrium and left atrium, and two lower chambers, known as the right ventricle and left ventricle. The heart also contains four valves as follows: Tricuspid valve: Located between the right atrium and right ventricle. Mitral valve: Found in the left atrium, it allows oxygen-rich blood from the lungs to pass into the heart in preparation for pumping it to all parts of the body. Pulmonary valve: Located between the right ventricle and the pulmonary artery... Let me know if you'd like to continue with this text or need further assistance.