I have a heart check pen that reads single lead ecg. Keeps saying wide QRS/IVCD. What's that mean? A 12 lead I had a month ago didn't say that.

False reading? Since your EKG recently was normal it's quite possible your "heart check pen" is giving you a false reading. IVCD refers to intra-ventricular conduction delay. The AV node initiates a wave of depolarization that travels down the bundle of HIS which, in turn, divides into the left and right bundle. A partial or complete block of one of these branches causes a delay in contraction and a wide QRS.
Meaning of EKG. The EKG measures the electrical activity of your heart muscle as it appears on the surface of your body. It usually looks like a regular appearing bunch of up-and down squiggles which doctors have learned to interpret as various disease states of your heart muscle( heart attack, etc). The middle set of wiggles is called the QRS complex and if it is widened, it is taking too long. The 12 lead is be.