undersensing

un·der·sens·ing

(ŭn'dĕr-sens'ing), Nonsensing of the intracardiac atrial or ventricular depolarization signal by a pacemaker.

undersensing

Cardiology Failure of a pacemaker to sense the P or R waves, which may cause the pacemaker to emit inappropriately timed impulses. See Pacemaker.