How is the QRS complex traditionally presented on lead V6?

How is the QRS complex traditionally presented on lead V6?

• A. It is normally negative
• B. It is normally positive
• C. It varies widely
• D. It is absent

Answer: (B)

The QRS complex in lead V6 is typically presented as positive in a healthy individual, reflecting the normal electrical activity of the heart as it depolarizes. Lead V6 is placed on the left side of the chest, in the mid axillary line, which is an area conducive to detecting the left ventricular activity prominently.

In lead V6, a positive QRS suggests that the bulk of the ventricular depolarization is directed towards this lead. This positive deflection corresponds to the left ventricle being the primary source of depolarization during the heartbeat, as the left ventricle normally makes up the greater part of the heart’s mass and hence contributes significantly to the electrical vectors during depolarization.

Other presentations of the QRS complex are less typical in a healthy heart; for instance, a negative QRS in this lead may signify certain types of abnormalities or conditions related to heart position or structural changes. Therefore, identifying the QRS complex as normally positive in lead V6 is crucial for interpreting EKG readings correctly.