How does lead reversal affect an EKG reading?

Lead reversal can significantly impact the interpretation of an EKG reading by misrepresenting the cardiac axis. When leads are placed incorrectly, the electrical activity of the heart is not accurately captured, leading to a distortion in the EKG waveform. Specifically, this can cause the EKG to reflect an altered position of the heart's electrical activity, making it appear as if the heart is oriented differently than it actually is.

For instance, if the leads are reversed, what should be positive deflections may turn negative, which can lead to confusion in diagnosing various cardiac conditions. This misinterpretation can have consequential effects, including incorrect assessments of arrhythmias or other heart problems. Correct lead placement is crucial to obtaining a reliable interpretation of the heart's electrical activity, emphasizing the importance of accurate lead positioning in EKG testing.