What is an electrophysiological examination? An electrophysiological test is a method that accurately evaluates the function of the heart’s electrical activity. This test allows the doctor to identify abnormal areas of the heart that are causing arrhythmias (abnormal heart rhythms). During the test, a special electrode catheter (a long, flexible, bendable guidewire) is inserted into a vein and introduced into the heart. The inserted catheter can both detect electrical impulses in different parts of the heart and deliver electrical stimulation to different parts of the heart. Why is electrophysiological testing important? Electrophysiological testing provides more precise and detailed information about the electrical activity of the heart than other diagnostic methods. It can help doctors make an accurate diagnosis and choose the most effective treatment. It is the most effective way to diagnose severe life-threatening arrhythmias and persistent arrhythmias that cannot be diagnosed by other methods.