electrical alternation

[ĭ-lĕktrĭ-kəl]
n.
  1. A varied alternation in the activity of the heart indicative of myocardial disease as measured by an electrocardiograph.electrical alternans
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.