Air Methods Critical Care Practice Exam

Lead II is primarily utilized to view the apex of the heart. This is because Lead II is positioned to create an angle of about 60 degrees relative to the heart’s electrical activity, allowing it to capture the impulses as they travel toward the apex. The positive electrode of Lead II is placed on the left leg, while the negative electrode is on the right arm, creating an effective path for detecting the predominantly downward and leftward electrical impulses during depolarization of the heart.

This positioning results in a strong waveform when the heart beats, as the electrical activity points toward the positive lead during the P wave, QRS complex, and T wave phases, making it particularly sensitive to changes in the apex This unique perspective provides significant information for interpreting cardiac conditions, especially those affecting the inferior wall of the heart.