Cardiac anatomy

• Blood circulation in the body


  1. Deoxygenated blood enters heart through superior and inferior vena cava into right atrium

  2. Blood goes through tricuspid valve into right ventricle

  3. Right ventricle pumps blood through pulmonary valve into pulmonary artery to lungs

  4. Oxygenated blood returns to heart through pulmonary veins into left atrium

  5. Blood goes through bicuspid valve into left ventricle

  6. Left ventricle pumps blood through aortic valve into aorta to body
• Pulmonary circulation


  Circuit where blood goes from heart to lungs and back
• Systemic circulation


  Circuit where blood goes from left ventricle to body and back to heart
• Heart


  • Apex directed forward and downward to left
  • Base directed backward and slightly right, connected to great vessels
• Surfaces of the heart


  • Pulmonary surface
  • Sternocostal surface
  • Diaphragmatic surface
• Margins of the heart


  • Only right margin, between sternocostal and diaphragmatic surfaces
• External structures of the heart


  • Coronary sulcus separates atria from ventricles
  • Anterior and posterior interventricular sulci separate right and left ventricles
• Interventricular septum


  Wall separating right and left ventricles, has muscular and membranous parts
• Interatrial septum


  Wall separating right and left atria
• Anatomy of right atrium


  1. Anterior wall has right auricle with pectinate muscle

  2. Superior wall has opening for superior vena cava

  3. Posterior wall has opening for inferior vena cava, sinus of vena cava, and valve for inferior vena cava

  4. Medial wall is interatrial septum with oval fossa, border of oval fossa, opening for coronary sinus with valve

  5. Inferior wall has right atrioventricular orifice guarded by tricuspid valve
• The heart is tilted forward, so the inferior vena cava becomes part of the posterior wall
• The sinus of vena cava is the area for the SA node, the conductive system
• The valve for the inferior vena cava is an embryonic valve that allows blood to bypass the lungs in the fetus
• Limbus of oval fossa


  Structure found in the heart
• Coronary sinus


  Opening for the main vein draining blood from the heart
• Valve for the coronary sinus


  Fold covering the opening of the coronary sinus
• Openings of the smallest cardiac veins


  Small openings returning blood directly from the layers of the heart's wall
• Right atrioventricular orifice/opening


  Opening between the right atrium and the right ventricle
• Tricuspid valve


  Valve with three cusps/leaflets that prevents the backflow of blood between the right atrium and right ventricle
• Tricuspid valve


  • Anterior cusp
  • Posterior cusp
  • Septal cusp
• Trabeculae carneae


  Rough inner layer of the right ventricle that prevents the blood from swirling around
• Papillary muscles


  Muscles connected to the tricuspid valve that control its opening and closure
• Pulmonary valve


  Valve with three semilunar cusps that allows blood to flow from the right ventricle to the pulmonary artery
• Pulmonary valve


  • Semilunar cusps
  • Nodules of the semilunar valve
  • Sinus of the pulmonary trunk
• Blood flow through the right side of the heart


  1. Right atrium

  2. Tricuspid valve

  3. Right ventricle

  4. Pulmonary valve

  5. Pulmonary artery
• Left auricle


  Muscle pouch containing pectinate muscle on the anterior wall of the left atrium
• Pulmonary veins


  Blood vessels on the posterior wall of the left atrium that bring oxygenated blood from the lungs
• Interatrial septum


  Medial wall of the left atrium that separates the two atria
• Left atrioventricular opening


  Opening between the left atrium and left ventricle
• Bicuspid valve/Mitral valve


  Valve with two cusps that guards the left atrioventricular opening
• Mitral valve


  • Anterior cusp
  • Posterior cusp
  • Commissural cusps
• Trabecula carneae


  Rough inner layer of the left ventricle that prevents the blood from swirling around
• Papillary muscles


  Muscles connected to the mitral valve that control its opening and closure
• Aortic vestibule


  Region inside the left ventricle that leads to the aortic opening
• Aortic valve


  Valve with three semilunar cusps that allows blood to flow from the left ventricle to the aorta
• Aortic valve


  • Right semilunar cusp
  • Posterior semilunar cusp
  • Left semilunar cusp
  • Nodules
• Aortic sinuses


  Depressions formed by the semilunar cusps of the aortic valve
• Blood flow through the left side of the heart

  1. Left atrium

  2. Mitral valve

  3. Left ventricle

  4. Aortic valve

  5. Aorta