Cardiovascular System

• Parts of the Blood Vascular System


  • Blood
  • Heart
  • Circulatory system
  • Lymphatic system

  
• Blood


  Fluid that transports oxygen and nutrients around the body and collects the waste product of tissues
• Circulatory system


  Network of artery, veins and capillaries in which blood flow through

  
• Lymphatic system


  Network of lymphatic vessels that transport lymph or excess tissue fluid around body and responsible for returning them into circulation

  
• Types of Circulation


  • Pulmonic
  • Systemic
• Pulmonic circulation


  Flows through right side of the heart to the lungs
• Systemic circulation


  Flows through left side of the heart to the heart itself and rest of the body
• Blood


  • Transports oxygen and nutrients
  • Collects waste products of tissues
  • Around 6-8% of animal's body weight
  • Circulation time: 30 seconds in large animals, 7 seconds in cats
• Heart


  • Muscular and four chambered organ
  • Pumps blood into circulatory system

  
• Heart (in dogs)


  • Ovoid shape with blunt apex and base
• External Structures of the Heart


  • Pericardium
  • Pericardial space
  • Pericardial fluid

  
• Pericardium


  The heart sac, a double-walled membrane enclosing the heart
• Pericardial space


  Found between the two layers of the serous pericardium, contains the pericardial fluid
• Pericardial fluid


  Prevents friction between the heart and the pericardium
• Deep Layers of the Heart


  • Epicardium
  • Myocardium
  • Endocardium

  
• Epicardium/Visceral Pericardium


  External layer, also part of the serous layer of the pericardium
• Myocardium


  Middle and thickest layer, considered as the actual "heart muscle"

  
• Endocardium


  Inner layer, lines the heart chambers and valves
• Other Structures of the Heart


  • Coronary Groove
  • Interventricular Groove
  • Ligamentum Arteriosum
  • Coronary Sinus

  
• Coronary Groove


  Partially encircling the heart, separates the atria and the ventricle, contains the Coronary Artery

  
• Interventricular Groove


  On the heart's exterior, indicates the interventricular septum separating the two ventricles, contains the Paraconal artery on the left side and the Subsinousal artery on the right side

  
• Ligamentum arteriosum


  Remnant of fetal ductus arteriosus

  
• Coronary sinus


  Termination of the coronary vein emptying into the right atrium
• Chambers of the Heart


  • Right Atrium
  • Right Ventricle
  • Left Atrium
  • Left Ventricle
• Right Atrium


  Forms the right dorsocranial part of the base, receives deoxygenated blood of the body

  
• Structures in the Right Atrium


  • Sinus of vena cava
  • Right auricle
  • Interarterial septum
  • Intervenous tubercle
  • Oval fossa/Fossa Ovalis
  • Muscular bands/Pectinate muscle

  
• Openings of the Right Atrium


  • Cranial Vena Cava
  • Caudal Vena Cava
  • Coronary sinus
  • Right Atrioventricular Orifice

  
• Right Ventricle


  Receives blood from the right atrium, contracts to send the deoxygenated blood to pulmonary trunk to the lungs, does not extend into the apex

  
• Structures in the Right Ventricle


  • Conus Arteriosus
  • Supraventricular crest
  • Right Artrioventricular Valve/Tricuspid valve
  • Chordae Tendinae
  • Papillary Muscles

  
• Left Atrium


  Forms the left, dorsocaudal part of the base, receives oxygenated blood from the lungs via pulmonary veins

  
• Left Ventricle


  Forms the apex of the heart, has the thickest wall among the heart compartments, pumps the oxygenated blood to the aorta to the body

  
• Structures of the Left Ventricle


  • Left Atrioventricular Valve or Bicuspid or Mitral Valve
  • Papillary muscles
  • Aortic orifice
• Valves of the Heart


  • Right Atrioventricular or Tricuspid Valve
  • Aortic Valve/Semilunar Valve
  • Pulmonary Valve
  • Left Atrioventricular or Bicuspid Valve
• Right Atrioventricular or Tricuspid Valve


  3 cusps: Parietal Cusp, Angular Cusp, Septal Cusp
• Aortic Valve/Semilunar Valve


  3 cusps: Septal semilunar valvula, Right semilunar valvula, Left semilunar valvula
• Pulmonary Valve


  3 cusps: Right semilunar valvula, Left semilunar valvula, Intermediate semilunar valvula
• Left Atrioventricular or Bicuspid Valve

  2 cusps: Parietal cusp, Septal cusp
• Cardiac Conducting System


  Sinoatrial node (SA node), Atrioventricular node, Atrioventricular bundle of His, Right and Left branches of the bundle of His, Subendocadial Purkinje fibres or Purkinje fibers
• Sinoatrial node (SA node)


  Pacemaker of the heart, superior to the sulcus terminalis of the right atrium, below opening of superior vena cava, generates and propagates electrical impulses, governs the contraction of cardiac muscles producing the heart beats, branches out to the atrioventricular node
• Atrioventricular node


  Smaller than SA node, located in the right atrium, posteroinferior part is at the interatrial septum next to septal cusps, picks up and continues action potentials by SA nodes, may propagate some of its own action potential, innovative area covers the atria of the heart, branches into the bundle of His