Normal ECG Flashcards
P Wave positioning and values
Upright in 1, 2, V4-6, aVF
Inverted in aVR
PR Interval definition and timing
Time it takes from SA node to ventricular muscle fiber
0.12-0.2 seconds
QRS complex timing
0.05-0.12 seconds duration.
Q waves values and appearance
Should not be more than 0.03 seconds.
Q waves should be narrow/small. 1-2 mm is normal.
ST segment and appearance
Normally is isoelectric, but should not be elevated more than 1 mm in standard leads and 2 mm in chest leads.
Never should be depressed more than 0.5 mm.
Depressed ST segment could be a sign of:
Subendocardial pathology
Elevation of ST segment could be a sign of:
Subepicardial, transmural injury or ischemia.
T wave values and orientation
Upright 1, 2, V3-6.
Inverted in aVR.
Should not be greater than 5 mm in standard leads and 10 mm in chest leads.
Deviations of QT duration could be a sign of:
Myocardial ischemia, myocardial injury, or MI.
Inverted T wave could mean:
Ischemia
Q wave or QS complex abnormalities could mean:
Pattern of necrosis or infarction.
Absence of P waves could mean:
AFib, atrial flutter, ventricular escape rhythms, junctional tachycardia, VT.
Normal axis is a deflection in which leads?
Positive deflection in leads I and aVF
Left axis is a deflection in which leads?
Positive deflection in lead I and negative deflection in lead aVF
Right axis is a deflection in which leads?
Negative deflection in lead I and a positive deflection in aVF.
