electrokymograph

[ĭ-lĕk′trō-kīmə-grăf′]
n.
  1. An apparatus for recording the movements of the heart and great vessels by observing changes in the x-ray silhouettes. No longer in technical use.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.