Abstract
There is an increasing need for nurses to interpret a 12-lead electrocardiogram, both in critical care units and in other areas. This can be a challenging task, especially in the presence of hypertrophies, bundle-branch blocks, and fascicular blocks. This article reviews the pathophysiology of intraventricular blocks and hypertrophy, characteristics found in the 12-lead electrocardiogram, and discusses what the significance of these findings may be.