The Collaborative International Dictionary of English v.0.48:

Sphygmogram \Sphyg"mo*gram\, n. [Gr. ???? pulse + -gram.]
   (Physiol.)
   A tracing, called a pulse tracing, consisting of a series of
   curves corresponding with the beats of the heart, obtained by
   the application of the sphygmograph.
   [1913 Webster]