Cardio

• Heart


  The major pumping organ of the body
• Heart


  • In resting adult the heart contracts 60–100 bpm while pumping 4 – 5L/min blood
  • Located in the thoracic cavity between the lungs and above the diaphragm in an area known as mediastinum
• Anatomical divisions of the heart

  • Base - uppermost portion which includes the left and right atria as well as the aorta, pulmonary arteries and superior vena cava and inferior cava
  • Apex – lower portion which extends into the left thoracic cavity covering the heart to appear as if it is lying on the right ventricle
• Pericardium


  The sac that encloses the heart, made up of three layers: outer fibrous layer, a pair of inner serous membranes (parietal and visceral), and pericardial fluid between the serous layers
• Heart walls

  • Epicardium (visceral pericardium)
  • Myocardium - muscular layer
  • Endocardium - thin sheet of endothelium that lines the heart chambers
• Heart valves

  Allow blood to flow in only one direction through the heart chambers—from the atria through the ventricles and out the great arteries leaving the heart
• Atrioventricular (AV) valves

  • Left AV valve (bicuspid/mitral valve) - two flaps
  • Right AV valve (tricuspid valve) - three cusps
• Semilunar valves

  • Pulmonary valve
  • Aortic valve
• Cardiac cycle

  • Systole - contraction phase, triggered by the depolarization of cardiac muscles
  • Diastole - relaxation or filling of blood; repolarization phase
• Heart sounds

  • S1 - closure of the AV valves
  • S2 - closure of the semilunar valves
  • S3 - ventricular gallop (often normal in younger than 30 but pathologic in older ages)
  • S4 - atrial gallop due to the resistance to ventricular filling as in ventricular hypertrophy
• S1


  Dull, low-pitched sound described as "lub", occurs when the atrioventricular (AV) valves close
• S2


  Higher pitch than S1 and shorter in duration, occurs when the semilunar valves close
• Systole


  Period in which the ventricles contract, begins with S1 and ends at S2, normally shorter than diastole
• Diastole


  Period in which the ventricles relax, starts with S2 and ends at the subsequent S1
• Heart conduction system

  • Sinoatrial node - major pacemaker of the heart, initiating electrical impulses at an intrinsic rate of 60-100
  • Atrioventricular node > Bundle of His > Right and Left Bundle Branches > Purkinje Fibers
• Phases of cardiac contraction

  • P - atrial depolarization
  • QRS - ventricular depolarization
  • T - ventricular repolarization
  • U - precise activity is unknown
• Health history factors

  • Age: Childhood onset - rheumatic fever, Adult onset - HTN, CAD, MI, AAA
  • Gender: Female and Male
  • Race: may predispose to higher risk for CVA, CAD, HTN, DM
• Common chief complaints

  • Chest pain
  • Syncope
  • Palpitations
  • Peripheral edema
  • Extremity pain
• Components of cardiovascular assessment

  • Assessment of the precordium
  • Assessment of the periphery
• Assessment of the precordium

  1. Simultaneously inspect and palpate for abnormal pulsations, lifts or heaves

  2. Inspect jugular vein for distention

  3. Locate the valve areas of the heart
• Cardiac landmarks and locations

  • Angle of Louis - prominence on sternum
  • Aortic area - 2nd intercostal space right of sternum
  • Pulmonic area - 2nd intercostal space left of sternum
  • Tricuspid area - 5th intercostal space left of sternum
  • Mitral/apical area - 5th intercostal space left midclavicular line
• Precordial palpation techniques

  • Pulsations - using finger pads
  • Thrills - using palmar surface of hand
  • Heaves - using palmar surface of hand
• Normal precordial findings

  • Pulmonic - no pulsations visible
  • Aortic - no pulsations visible
  • Tricuspid - no pulsations visible
  • Apical - with or without pulsations visible
  • Epigastric - abdominal aortic pulsations visible
• Auscultation of the heart

  1. Eliminate room noise

  2. Keep patient in supine position with head elevated 15-45 degrees

  3. Use both diaphragm and bell to listen in all areas

  4. Distinguish S1 and S2 sounds in each area

  5. Focus on one sound at a time - S1, systole, S2, diastole
• Normal auscultation findings


  • S1 - usually heard at all sites, usually louder at apical area
  • S2 - usually heard at all sites, usually louder at base of heart
  • Systole - silent interval, slightly shorter than diastole
  • Diastole - silent interval, slightly longer than systole
• Cardiac landmarks and locations (mnemonic)

  • All - Aortic area, 2nd intercostal space right of sternum
  • People - Pulmonic area, 2nd intercostal space left of sternum
  • Eat - Erb's Point/Midprecordial area, 3rd intercostal space left of sternum
  • Tinolang - Tricuspid/septal area, 5th intercostal space left of sternum
  • Manok - Mitral/apical/PMI area, 5th intercostal space left midclavicular line
• Murmurs


  Longer duration than heart sounds, can be functional (normal blood flow) or pathological (related to structural abnormalities)
• Murmur grading

  • Grade I - Very faint, barely audible
  • Grade II - Clearly audible, faint thrills
  • Grade III - Moderate sound and thrills
  • Grade IV - Loud with palpable thrill
  • Grade V - Very loud with palpable thrill, can be heard with partial stethoscope contact
  • Grade VI - Extremely loud, heard with stethoscope lifted off chest, palpable thrill
• Carotid artery auscultation

  1. Turn patient's head slightly away from side being examined

  2. Auscultate one carotid artery then the other

  3. Listen for presence of bruit, palpate for thrill if bruit heard
• Pulse palpation sites

  • Temporal
  • Carotid
  • Apical
  • Brachial
  • Radial
  • Femoral
  • Popliteal
  • Posterior tibial
  • Dorsalis pedis
• Pulse assessment

  • Rate
  • Strength (0 absent, +1 weak, +2 normal, +3 bounding)
  • Rhythm (regular or irregular)
• Homan's test


  With patient's knee slightly bent, sharply dorsiflex the patient's foot and ask if this elicits calf pain
• Allen's test


  Assess patency of radial and ulnar arteries, usually performed prior to radial artery cannulation