Cardiovascular System

• Cardiovascular System

  • Regulates blood supply
  • Generates blood pressure
  • Routes blood
  • Ensures 1-way blood flow
• Pericardium - doublelayered sac that anchors and protects heart
• Parietal pericardium - membrane around heart’s cavity
• Visceral pericardium - membrane on heart’s surface
• Pericardial cavity - space around heart
• Heart Layers

  • Epicardium: surface of heart (outside)
  • Myocardium: thick, middle layer composed of cardiac muscle
  • Endocardium: smooth, inner surface
• Coronary sulcus - separates atria from ventricles
• veins - carry deoxygendated blood
• artery - carry oxyganated blood away from the heart
• Atria - The upper chambers of the heart that r, contract minimally to push blood into ventricles
• Interatrial septum - separates right and left atria
• Valves - prevent backflow of blood into the heart and allow blood to flow in 1 one direction
• Ventricles - The two lower chambers of the heart that pump blood out of the heart.
• Atrioventricular valves (AV): between atria and ventricles

  • Tricuspid valve - AV valve between RA and RV; 3 cusps
  • Bicuspid valve (mitral) - AV valve between LA and LV; 2 cusps
• Semilunar valves

  • Pulmonary: base of pulmonary trunk
  • Aortic: base of aorta
  • Chordae tendineae: attached to AV valve flaps ; support valves
• coronary sinus - drains blood from the heart to the lungs
• Superior vena cava - drains blood above diaphragm
• Inferior vena cava - drains blood below diaphragm
• Right Atrium - receives blood from 3 places: superior and inferior vena cava and coronary sinus
• Right Ventricle - opens into pulmonary trunk
• Aorta - carries blood from Left Ventricle to body
• Left Atrium - 4 openings (pulmonary veins) that receive blood from lungs
• Coronary arteries - supply blood to heart wall
• Peacemaker potential - Changes in membrane channels’ permeability are responsible for producing action potentials
• Depolarization phase

  • Sodium ions channels open
  • Calcium ions channels open
• Plateau phase


  • Sodium ions channels close
  • Potassium some open
  • Calcium open
• Conduction System - contraction of atria and ventricles by cardiac muscle cells
• Electrocardiogram - a recording of the electrical activity of the heart.
• Stethoscope - used to hear lung and heart sounds
• Intrinsic Regulation - mechanisms contained within heart
• Chemical Regulation - chemicals can affect heart rate and stroke volume
• Factors Modifying Basic Heart Rate

  • Neural (ANS) controls
  • Hormones and ions
  • Physical factors
• Aortic valve - Heart valve that prevents backflow from the aorta to the left ventricle
• Mitral valve - The valve that regulates blood flow between the left atrium and left ventricle
• Tricuspid valve - The valve that regulates blood flow between the right atrium and right ventricle
• Pulmonic valve - The valve that regulates blood flow between the right ventricle and pulmonary arteries
• Heart sound is First sound is lubb, second is dupp
• Left Ventricle - opens into aorta
• Stroke volume - The amount of blood ejected by the heart with each beat / volume of blood pumped per ventricle per contraction
• Rhythmicity - Term applied to the heart’s ability to beat regularly