Clinical value of lead aVR.

Lead aVR is the only lead in the surface ECG that does not face the "typically" relevant walls of the left ventricle. Historically, its value has been neglected most likely due to its unusual configuration and direction, which appeared to have little correlation with other more congruous and easily diagnostic frontal leads. The isolation of the unipolar leads in the Standard surface ECG presentation may also have played an important role. Even with this "unfair" neglect, we know nowadays that it is very sensitive to locate obstructed epicardial coronary arteries. Besides helping distinguishing the culprit lesion of an infarct, lead aVR also helps recognizing other conditions that could be of clinical significance such as pericarditis, Brugada syndrome, fascicular blocks of the right branch, ectopic left atrial rhythms, etc. The purpose of this review is to revise the clinical value of lead aVR in the recognition of frequent and not so frequent clinical conditions. ©2011, Wiley Periodicals, Inc.