1. INTRINSIC CONTROL OF THE HEART
    1. ▪ Cardiac tissue is capable of AUTOCONDUCTION ▪ CARDIAC CONDUCTION SYSTEM (CCS) has own conduction system – initiates own pulse without neural control.
    2. Components of Cardiac Conduction System : ▸SA node ▸AV node ▸AV Bundle ▸Purkinje fibers
  2. EXTRINSIC CONTROL OF THE HEART
    1. Controls of the cardiovascular system include neuronal, humoral, reflex, and chemical regulatory mechanisms. These extrinsic controls regulate heart rate, myocardial contractility, and vascular smooth muscle to maintain cardiac output, blood flow distribution, and arterial blood pressure.
  3. THE HEART
    1. HEART RATE
      1. Increase work will increase HR
      2. RHR increases with age
      3. MHR = 220 – age
    2. STROKE VOLUME
      1. volume of blood pumped per stroke
      2. SV increases with increase rate of work
    3. CARDIAC OUTPUT (Q)
      1. total volume of blood pumped out in 1 minute
      2. Q = HR x SV (average = 60-80ml in adults)
      3. Q increases with increase rates of work
    4. BLOOD FLOW
      1. ➠ During rest = 15-20% of resting Q ➠ During exercise = increase up to 80% of Q
      2. During exercise in the heat, there is increase blood flow to the skin
    5. BLOOD PRESSURE
      1. pressure exerted by blood against the blood vessels
      2. Systolic = highest P in the artery Diastolic = lowest P in the artery
      3. normal BP = 120/80 mmHg
    6. BLOOD
      1. transporting oxygen and nutrients to the lungs and tissues
      2. forming blood clots to prevent excess blood loss
  4. STRUCTURE AND FUNCTION OF THE CARDIOVASCULAR SYSTEM
    1. ► The Heart (The pump) ► The Vascular System ► The Blood ⊳ Cardiac muscle is called the MYOCARDIUM.
  5. ARRYTHMIA
    1. Bradycardia : slow heartbeat
    2. Tachycardia : fast heartbeat
    3. Flutter/fibrillation : irregular heartbeat
    4. Premature contraction : early heartbeat
  6. CARDIAC CYCLE
    1. Relaxation phase (Diastole)
    2. Contraction phase (Systole)
  7. Hematocrit
    1. is the % rbc volume in the whole blood
  8. VASCULAR SYSTEM
    1. ➭ Arteries ➭ Arterioles ➭ Capillaries ➭ Venules ➭ Veins
  9. Distribution of blood
    1. At rest – 15% to skeletal muscles ☛ 22% to kidneys ☛ 27% to liver
    2. During exercise – up to 80% to skeletal muscles