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Old 08-22-2012
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Default Heart electrical axis - what in ECG?

An electrocardiogram from a 60-year-old man with a 20-year history of poorly controlled systemic hypertension shows normal sinus rhythm and no evidence of conduction abnormalities. The mean electrical axis of ventricular depolarization is −30°. When examining the frontal plane leads of his electrocardiogram, which of the following observations regarding the net QRS voltage would most likely be made?

a) A net negative voltage in lead I
b) A positive voltage in lead aVL
c) The largest net voltage in lead II
d) The smallest net voltage in lead III
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Old 08-23-2012
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anybody?
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Old 08-23-2012
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Default correct answer

again, the correct answer for 'future generations'

The answer is b) A positive voltage in lead aVL

The positive terminal of lead aVL is located at −30°. This patient’s mean QRS axis is parallel with the positive end of lead aVL, which thus records a large positive voltage.
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