An EKG is a simple, painless test that records the heart’s electrical activity. To understand this test, it helps to understand how the heart works. With each heartbeat, an electrical signal spreads from the top of the heart to the bottom. As it travels, the signal causes the heart to contract and pump blood. The process repeats with each new heartbeat. The heart’s electrical signals set the rhythm of the heartbeat. An EKG measures the regularity or irregularity of the heart beat and gives valuable feedback to our physician in determining if there is a potential problem with the heart.