Cardiac Electrophysiology Studies (EPS) is the study of the heart’s electrical structure and function (physiology). Electrical activity in the heart tells the muscle when to beat and pump blood out and on its journey through the body.
Sometimes the electrical impulse becomes “out of sync”. Symptoms for this can range from the odd “skipped beat” to recurrent “palpitations”. These arrhythmias (abnormal heart rhythms) mean that the heart may not contract properly and therefore may not pump blood as it should. Arrhythmias are a failure of your natural pacemaker or conduction system to work properly, resulting in an inappropriately slow or fast heart
Treatment for these conditions depends on exactly where the problem originates. Generally, the arrhythmias that we are most concerned about are the ones that produce either a very slow heart rate (bradycardia) or a very rapid heart rate (tachycardia) that result in inefficient pumping action of your heart. The result of blood not being pumped efficiently is that you may become dizzy or, in extreme cases, actually blackout.
In an EPS, a few small incisions are made in your right groin using local anaesthetic and up to four long, thin wires called catheters are advanced into the heart via the blood vessels. These catheters are guided into the heart using X-ray imaging. The catheters have small electrodes on them that enable electrical information (electrograms) to be recorded, and specific pacing/stimulation to be performed on your heart. By positioning the catheters in specific areas of your heart and by reading the electrical impulses that pass through it, the normal electrical conduction sequence is determined. When the heart is in an arrhythmia the conduction sequence alters. By fine tuning the catheter positions the precise location and mechanisms of the arrhythmias can be worked out. Treatment of the arrhythmia can now be tailored to suit the individual problem. Bradycardias can be effectively and reliably treated using implantable cardiac pacemakers. Tachycardias are treated either with radio-frequency (RF) ablation, drug therapy or implantable devices.