Electrocardiography ECG , is a test that records the heart rhythm and electrical activity of the heart's conduction system . It's this electrical activity that makes your heart contract, so when measured, it can identify problems with your heart rate and rhythm. An ECG is painless and only takes about minutes. In this test, several small adhesive patches are placed on your wrist, ankle, and chest. These patches are connected to wires that lead to a recording machine. The machine doesn't give you electrical shocks or affect your heart in any way. The machine records a few beats on paper. Your doctor will review this to see if :<br />• If there are any heart rhythm problems .<br />• I got it with a heart attack Recently or long ago .<br />• Your blood supply is decreased (ischemia