Figure 94-15

LPFB with RBBB.A. No MI .B. . Anteroseptal MI (note q-wave inV2). C. Inferior MI (note ST- segment elevation and T wave inversion in leads 11 and AVF with slight ST-segment depression in lead I). The difference between A and C are not very marked since pure LPFB may produce an almost abnormal Q wave in the inferior leads. Conversely, this conduction disturbance, by producing an initial depolarization wave front oriented superiorly is capable of decreasing the depth (thus normalizing) the abnormal Q-wave characteristic of inferior MI in leads 11,111, and AVF.