Laboratory and Diagnostic Test

• CBC


  For evaluation of general health status.
• CBC

  Elevated RBCs suggest inadequate tissue oxygenation. Hypoxia stimulates renal secretion of erythropoietin. This stimulates the bone marrow to increase RBC production (polycythemia)
• CBC

  Elevated WBCa may indicate infectious heart disease and myocardial infarction.
• CBC

  Normal Values:

  • RBC - 4.5 to 5.5. M/cu.mm.
  • WBC - 5000 to 10000 /cu.mm
  • Platelets - 150000 to 450000 /cu.mm
  • Hemoglobin
  • Male - 13 to 18 g/dL
  • Female - 12 to 16 g/dL
  • Hematocrit
  • Male - 39 to 54 %
  • Female - 36 to 48 %
• Erythrocyte Indices

  MCV - mean corpuscular volume

  MCH - mean corpuscular hemoglobin

  MCHC - mean corpuscular hemoglobin concentration

  • These are the best indicators of anemia.
  • MCV and MCH are increased in macrocytic anemia; decreased in microcytic anemia.
  • MCHC is decreased in severe hypochromic anemia.
• Blood Coagulation Test

  Prothrombin Test (PT)

  • measures the time required for clotting to occur after thromboplastin and calcium are added to decalcified plasma.
• Blood Coagulation Test

  Partial Thromboplastin Test (PTT)

  • measures the time required for clotting to occur after partial thromboplastin reagent is added to plasma.
• Blood Coagulation Test

  Activated Partial Thromboplastin Time

  • same purpose as PTT.
• Blood Coagulation Test

  Prothrombin Test (PT)

  • It is valuable in evaluating the effectiveness of coumadin.
• Blood Coagulation Test

  Partial Thromboplastin Test

  • It is the best single screening test for disorders of coagulation.
• Blood Coagulation Test

  Partial Thromboplastin Test

  • It is determined to evaluate the effectiveness of Heparin.
• Blood Coagulation Test

  Activated Partial Thromboplastin Test

  • It is the most specific test to evaluate effectiveness of Heparin.
• Blood Coagulation Test

  PT

  • Normal range: 11 to 16 seconds
  • Therapeutic range: 1.5 to 2 times
• Blood Coagulation Test

  PPT

  • Normal range: 60 to 70 seconds
  • Therapeutic range: 2 to 2.5 times
• Blood Coagulation Test

  APPT

  • Normal range: 30 to 45 seconds
  • Therapeutic range: 2 to 2.5 times
• Blood lipids

  Cholesterol: <200

  Triglycerides: <150

  LDL: <100

  HDL: >50
• Enzyme Studies

  Creatinine Phosphokinase (CK-MB)

  • It is the most cardiac specific enzyme.
• Enzyme Studies

  CK-MB

  • It is an accurate indicator of myocardial damage.
• Enzyme Studies

  Troponin

  • Best indicator for MI.
• Enzyme Studies

  Troponin

  • Negative result is normal.
• Electrocardiography 


  It is the graphical recording of the electrical activities of the heart.
• ECG 


  It is the first diagnostic test done when a cardiovascular disorder is suspected.
• Electrocardiography

  P wave: Atrial Depolarization

  Duration is 0.04 to 0.11 secs
• Electrocardiography

  PR interval: Time of impulse transmission from SA node to AV node.

  Duration is 0.12 to 0.20 secs
• Electrocardiography

  QRS complex: ventricular depolarization

  Duration is 0.05 to 0.10 secs
• Electrocardiography

  ST Segment: represents the plateau phase of the action potential.
• Electrocardiography

  T wave: Ventricular repolarization

  Should not exceed 5 mm amplitude.
• Common ECG Changes

  Hypokalemia

  • U wave
  • Depressed ST segment
  • Flat T wave
• Common ECG Changes

  Hyperkalemia

  • Wide QRS complex
  • Prolonged PR
  • Tall T wave
  • Flat P wave
• ECG:

  Myocardial Injury - ST Elevation

  Myocardial Ischemia - ST Depression

  Myocardial Infarction - pathologic Q wave
• ECG: Types

  Holter Monitoring

  • It is continuous ECG monitoring, over a 24 - hour period.
  • The portable monitor is called telemetry unit.
  • This attempts to assess the activities which precipitate dysrhythmias and the time of the day the patient experiences it.
  • The client records his activities during the entire period of monitoring.
  • The client may remove the monitor only when bathing.
• ECG: Types

  Stress Testing or Exercise Testing

  • ECG is monitored during exercise on a treadmill or a bicycle- like device.
• ECG: Types

  Stress Testing or Exercise TestingNursing Interventions

  Nursing Interventions

  • Avoid tea, coffee and alcohol on the day of the test. These may affect heart function.
  • Avoid smoking and taking nitroglycerine, 2 hours before the test. To prevent postural hypotension.
• ECG: Types

  Holter Monitoring

  • Coffee - yes
  • Antihypertensive - yes
  • Bath - yes
• ECG: Types

  Stress Test

  • Coffee - no
  • Antihypertensive - yes
  • Bath - no
• Cardiac Catheterization or Arteriogram


  Involves radiographic examination of the heart following administration of contrast medium via a catheter.
• Cardiac Catheterization

  For right - sided catheterization, the catheter is inserted via a vein; for left - sided catheterization, the catheter is inserted via an artery.
• Cardiac Catheterization

  Nursing Interventions: Before

  • Assess allergy to iodine and seafood.
  • Obtain baseline VS.
  • NPO for 4 to 6 hours.
  • Ask client to void to promote comfort.
  • Done under local anesthesia.
• Cardiac Catheterization

  Nursing Interventions: After

  • Bed rest. If a blood vessel in the upper extremity is involved, until VS are stable; if in the lower extremity, for 6 to 8 hours.
  • Monitor VS, especially peripheral pulses. Diminished or absent pulse indicates obstruction.
  • Apply pressure dressing over the puncture site. To prevent bleeding.
  • Immobilize affected extremity, in extension.
  • Monitor extremities for color, temperature, and tingling to assess for impaired circulation.
• MRI


  Strong magnetic field and radiowaves are used to detect and define differences between healthy and diseased tissues.