Cardiac Medicine Certification Practice Exam 2025 – Comprehensive Prep Guide

The presence of lead changes in V4, V5, and V6 is primarily associated with abnormalities in the left lateral wall of the heart. These leads are positioned over the left ventricle, and changes here typically reflect pathology involving that region. Therefore, if changes are noted in these leads, it is indicative of some form of left ventricular involvement.

While the confusion might stem from the broader context of cardiac enlargement or ischemia, the specific question regarding lead changes in V4, V5, and V6 most directly points to the left ventricle. This involvement can manifest due to conditions like ischemia, but in the context of your choices, the main takeaway is that these leads represent that area of the heart. The possibility of right ventricular wall involvement would be better reflected in leads such as V1 and V2, which are focused on the right ventricle. Normal heart activity would not typically present with changes in these leads, and infarction in the anterior wall is more commonly associated with leads V1 through V3.