Anatomy of the Heart and Major Blood Vessels

Cardiovascular System Anatomy

Structure of the Heart

  • Epicardium
    • The outer layer of the heart wall.
  • Myocardium
    • The muscular middle layer of the heart responsible for contracting and pumping blood.
  • Endocardium
    • The inner layer of the heart, lining the chambers and valves.

Heart Chambers

  • 4 Heart Chambers
    • Comprised of:
    • 2 Ventricles
      • The lower chambers that pump blood out of the heart.
    • 2 Atria
      • The upper chambers that receive blood returning to the heart.

Major Blood Vessels

  • Superior Vena Cava
    • Large vein carrying deoxygenated blood from the upper body to the heart.
  • Inferior Vena Cava
    • Large vein carrying deoxygenated blood from the lower body to the heart.
  • Right Pulmonary Vein
    • Vessel carrying oxygenated blood from the right lung to the heart.
  • Right Pulmonary Artery
    • Carries deoxygenated blood from the heart to the right lung.
  • Left Pulmonary Vein
    • Vessel carrying oxygenated blood from the left lung to the heart.
  • Left Pulmonary Artery
    • Carries deoxygenated blood from the heart to the left lung.
  • Pulmonary Trunk
    • Large vessel that splits into the right and left pulmonary arteries.
  • Great Cardiac Vein
    • Drains blood from the heart muscle back to the right atrium.

Heart Valves

  • Atrioventricular Valves
    • Ensure unidirectional blood flow from the atria to the ventricles.
    • Tricuspid Valve
      • Located between the right atrium and right ventricle.
    • Mitral Valve
      • Located between the left atrium and left ventricle.
  • Semilunar Valves
    • Control blood flow into the arteries leaving the heart.
    • Pulmonary Valve
      • Located at the entrance to the pulmonary trunk.
    • Aortic Valve
      • Located at the entrance to the aorta.

Septa of the Heart

  • Interatrial Septum
    • The wall that separates the left and right atria.
  • Interventricular Septum
    • The wall that separates the left and right ventricles.

Major Arteries Related to the Heart

  • Left Coronary Artery
    • Supplies blood to the left side of the heart.
  • Right Coronary Artery
    • Supplies blood to the right side of the heart.
  • Left Common Carotid Artery
    • Supplies blood to the left side of the head and neck.
  • Ascending Aorta
    • The part of the aorta that rises from the heart.
  • Descending Aorta
    • The portion of the aorta that descends into the abdomen.
  • Left Subclavian Artery
    • Supplies blood to the left arm.
  • Brachiocephalic Trunk
    • Branches into the right common carotid and right subclavian arteries, supplying blood to the right arm and head.