ANATOMY
LIMB VASCULATURE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Lead I
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Lead III
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Lead II
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Lead aVL
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Lead aVF
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Detailed explanation-1: -The most efficient way to estimate axis is to look at LEAD I and LEAD aVF. A positive QRS in Lead I puts the axis in roughly the same direction as lead I. A positive QRS in Lead aVF similarly aligns the axis with lead aVF. Combining both coloured areas – the quadrant of overlap determines the axis.
Detailed explanation-2: -AVL is on the left wrist or shoulder and looks at the upper left side of the heart. Lead l travels towards AVL creating a second high lateral lead. AVf is on the left ankle or left lower abdomen and looks at the bottom, or inferior wall, of the heart.
Detailed explanation-3: -AVf. Augmented vector foot. Left foot. These 3 leads create a triangle with the heart in the middle, as below. The lines into the centre indicate the line of sight of these leads.