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An upright QRS complex in leads I and aVF typically indicates a normal or right axis deviation. However, if lead II shows ambiguity, it complicates the interpretation. In standard ECG interpretation, an upright QRS in leads I and aVF confirms that the heart's electrical activity is directed downwards and to the left, which aligns with normal axis characteristics. When lead II is ambiguous, it often suggests the heart's axis does not align neatly with the standard definitions, leading to the possibility of other interpretations.

In this scenario, the upright complexes in both leads I and aVF suggest that the axis is either normal or deviated to the right, but the ambiguity in lead II makes it uncertain. This suggests a need to consider a broader range of possibilities, including left axis deviation or even an indeterminate axis due to this conflicting information.

While left axis deviation would typically present with a negative QRS in lead I and a positive QRS in lead II, the given information conflicts with that pattern. Hence, in light of the provided ECG findings, it suggests an indeterminate axis due to the equivocal nature of lead II in relation to the confirmed orientations in leads I and aVF.