Which lead placement is most useful for assessing the inferior wall of the heart?

The inferior wall of the heart is primarily supplied by the right coronary artery in most individuals. To assess the inferior wall through an electrocardiogram (ECG), leads that focus on the inferior aspect are utilized. Lead II provides an optimal view of the inferior wall because it is oriented in a way that aligns with the electrical activity of the inferior wall, capturing signals as they move from the atria down towards the ventricles.

Lead II records the electrical impulses traveling from the right arm to the left leg, essentially providing a perspective that reflects the inferior wall's activity. This makes it particularly valuable when detecting any abnormalities that might indicate ischemia or other pathologies affecting the inferior wall of the heart.

In contrast, the other leads mentioned do not focus specifically on the inferior wall. For instance, Lead I looks at the heart's activity from the left to the right arm and does not provide information on the inferior aspect, while Lead III also offers a view related to the left arm but again from a different angle that is less effective for directly assessing the inferior wall. Lead V1, being a precordial lead, focuses on ventricular activity but predominantly represents the right side. Therefore, Lead II is the most useful for assessing the inferior wall