Left Ventricular Hypertrophy by the Surface ECG

Left ventricular hypertrophy (LVH) is defined as an increase in left ventricular mass (LVM) associated with structural changes of myocardium. The increase in LVM and associated changes are associated with changes in depolarization and repolarization, manifested as a variety of altered QRS and T patterns. Increased QRS voltage has been considered to be a specific ECG finding in LVH, and ECG criteria based on this increased QRS voltage are generally recommended. These ECG changes are also predictive of adverse cardiovascular outcomes. However, it must also be noted that the majority of patients with increased LVM do not have increased QRS voltage. While this is often considered a limitation of ECG in LVH diagnosis, the authors of this minireview consider it more likely that the electrical effects, represented in the altered ECG, and the increased LVM are independent effects, associated by virtue of their common relationship with an underlying pathologic state. This revised view challenges cardiologists and electrocardiologists to explore the interrelationships between electrical, biochemical, and mechanical alterations of myocardial remodeling seen with heart disease, to advance our understanding of this process and its effects, including the evolution of the ECG changes known as "LVH".