HA PREFINAL

• Cardiovascular System


  Also known as Circulatory System, an organ system that permits blood to circulate and transport nutrients, oxygen, carbon dioxide, hormones, and blood cells to and from the cells in the body
• Functions of the Cardiovascular System

  • Provide nourishment
  • Help in fighting diseases
  • Stabilize temperature and pH
  • Maintain homeostasis
• Heart


  A muscular pump that forces blood through a system of vessels made of arteries, veins and capillaries
• Functions of the Heart

  • Generate Blood Pressure
  • Route Blood
  • Ensure One-way Blood Flow
  • Regulation of Blood Supply
• Size of the Heart

  Size of a fist, hollow, cone-shaped heart has a mass of 250 to 350 grams-less than a pound
• Dimensions of the Heart

  • Broad, flat base, or posterior surface, is about 9 cm wide and directed toward the right shoulder
  • The base extends vertically from the left second and fifth intercostal space and horizontally from the right edge of the sternum to the left midclavicular line
  • Its apex points inferiorly toward the left hip
• Mediastinum


  The central compartment of the thoracic cavity surrounded by loose connective tissue, as region that contains a group of structures within the thorax
• Precordium


  The part of the front of the chest wall that overlays the heart and the epigastrium
• Pericardial Cavity


  The cavity formed by the Pericardium that surrounds the heart
• Pericardium


  • Surrounds the heart and anchors it within the mediastinum
  • Has 2 layers: Fibrous pericardium and Serous pericardium
• Fibrous Pericardium


  Layer of connective tissue that provides support and protection for the heart, with attachments to the diaphragm, the sternum, and the vertebral column
• Serous Pericardium


  Contains the pericardial fluid, has 2 layers: Parietal pericardium and Visceral pericardium (epicardium)
• Layers of the Heart

  • Epicardium (visceral pericardium)
  • Myocardium
  • Endocardium
• Myocardium


  Cardiac muscles responsible for the contraction of the chambers
• Endocardium


  Lines the inner surface of the heart which allows blood to move easily through the heart
• Heart Chambers


  2 atria and 2 ventricles: Right and Left Atrium, Right and Left Ventricle
• Heart Septa


  Interatrial septum and Interventricular septum
• Heart Valves


  • Tricuspid Valve
  • Bicuspid (Mitral valve)
  • Pulmonic Semilunar Valves
  • Aortic Semilunar Valves
• Chordae Tendineae


  Tendon-resembling fibrous cords of connective tissue that connect the papillary muscles to the tricuspid valve and the bicuspid valve in the heart
• Coronary System


  Circulation of blood that supply oxygen to the myocardium, includes Coronary arteries and Coronary veins
• Sequence of Systemic Circulation

  Not provided
• Mechanism of a Heart Beat

  • The heart's conduction system consists of special electrical cells that generate and coordinate electrical impulses to the myocardial cells
  • Properties of the myocardial cells: Rhythmicity, Automaticity, Conductivity, Contractility, Excitability
• Components of the Conduction System

  • Sinoatrial Node (SA Node)
  • Atriventricular Node (AV Node)
  • Bundle of His / Atrioventricular Bundle
  • Left and Right Bundle Branches
  • Purkinjie Fibers
• Phases of the Electrocardiogram (ECG)

  • P wave: Atrial depolarization
  • PR interval: Time from beginning of atrial depolarization to beginning of ventricular depolarization
  • QRS complex: Ventricular depolarization
  • ST segment: Period between ventricular depolarization and beginning of ventricular repolarization
  • T Wave: Ventricular repolarization
  • QT interval: Total time for ventricular depolarization and repolarization
  • U wave: Final phase of ventricular repolarization
• Examples of Arrhythmia


  • Not provided
• Electrocardiogram (ECG/EKG)


  Procedure that measures electrical signals in the heart
• Normal Heart Beat


  60-100 beats per minute
• Normal Heart Sounds


  • Lubb (S1): Lower in pitch, occurs at beginning of ventricular systole from closure of AV valves
  • Dubb (S2): Occurs at beginning of ventricular diastole from closure of semilunar valves
• Cardiac Cycle


  Filling and emptying of heart chambers, has two phases: Diastole (filling, relaxation of ventricles) and Systole (emptying, contraction of ventricles)
• Atrial Systole


  Contraction of two atria
• Ventricular Systole


  Contraction of two ventricles
• Atrial Diastole


  Relaxation of two atria
• Ventricular Diastole


  Relaxation of two ventricles
• Cardiac Output


  Volume of blood pumped by either ventricle per minute, calculated as Stroke Volume x Heart Rate
• Stroke Volume


  Volume of blood pumped per ventricle each time the heart contracts, approximately 70mL per beat
• Heart Rate


  Number of times the heart contracts per minute, 72 bpm for adults
• Points of Auscultation


  • Aortic Area
  • Pulmonic Area
  • Erb's Point
  • Mitral (Apical Area)
  • Tricuspid Area
• How to Auscultate
• Blood Vessels


  Tubular structures carrying blood through tissues and organs, including veins, arteries, and capillaries
• Functions of Blood Vessels

  • Carry Blood
  • Exchange Nutrients, Waste Products and Gases
  • Transport Substances
  • Help Regulate Blood Pressure
  • Direct Blood Flow to Tissues