Pediatric Electrophysiology and Arrhythmia Conditions and Treatments

Here at Stanford Medicine Children’s Health, we are well known for our ability to treat all types of arrhythmias, even such rare ones as the inherited catecholaminergic polymorphic ventricular tachycardia, which affects one to five out of 10,000 children born each year. We treat atrial and ventricular arrhythmias and slow heartbeats (bradycardias) and fast heartbeats (tachycardias) alike. We treat the following arrhythmias and more:

• Arrhythmogenic right ventricular cardiomyopathy (ARVC): An inherited arrhythmia that can cause electrical instability and conduction abnormalities in the heart, which in turn can cause fainting and sometimes lead to heart failure or unexpected sudden cardiac arrest.
• Atrial flutter: A fast heartbeat in the upper chamber of the heart caused by changes in the electrical system of your child’s heart, usually seen in adult congenital heart disease.
• AV-nodal reentrant tachycardia (AVNRT): Also called A-V nodal reentry. A heart abnormality that produces a fast rhythm where the electrical impulse travels in and around the A-V node in a circle; the most common type of supraventricular tachycardia.
• Brugada syndrome: A rare genetic disorder that affects the heart’s electrical system with an increased risk of sudden cardiac arrest.
• Catecholaminergic polymorphic ventricular tachycardia (CPVT): A fast heart rhythm that can be triggered by stress or physical activity and develop into a complex arrhythmia.
• Complete heart block: When the electrical signal from the upper chamber of the heart can’t travel to the bottom chamber of the heart, it results in a slow heart rhythm originating from the bottom chamber of the heart.
• Hypertrophic cardiomyopathy (HCM): A thickening of the heart muscle over time, usually in the left ventricle, which can block the flow of blood to the heart or affect the mitral valve.
• Long QT syndrome: A rare genetic disorder of the heart’s electrical system that can lead to dangerous heart rhythms, fainting, and sudden cardiac arrest. 
• Second degree heart block: A disruption of the electrical conduction system from the upper to lower chambers of the heart, which results in skipped beats.
• Sinus node dysfunction (or sick sinus syndrome): The heart’s natural pacemaker, called the sinus node, doesn’t function properly, causing slow or fast rhythms.
• Supraventricular tachycardia (SVT or ARVT): From time to time, a heart beats very fast for a reason other than exercise, high fever, or stress. The electrical activity travels in a circle from the upper chamber to the lower in the heart and then back up again.
• Ventricular tachycardia:  A life-threatening condition in which an electrical signal is sent from the ventricles at a very fast but often irregular rate.
• Wolff-Parkinson-White Syndrome (WPW): A condition in which an electrical signal may arrive at the ventricle over an extra conduction pathway or a shortcut from the atria to the ventricles. This abnormality can cause SVT.

Treatments for Childhood Arrhythmias

Many types of arrhythmia can be managed with medication. Other therapies include ablation, which is a minimally invasive catheterization therapy to cure abnormal fast heart rhythms, or implantable devices, such as an ICD or pacemaker, to control the heartbeat and keep it steady.

Treatments include:

• Ablation: In this safe, outpatient procedure with a high success rate, we pinpoint the source of the arrhythmia and ablate, or eliminate it. We insert a catheter (a flexible, long wire) into a blood vessel to reach the heart. During this endoscopic, minimally invasive procedure, we employ three-dimensional navigational systems that allow us to see exactly where the catheter is in the heart. Once we identify the source of arrhythmia, we either burn (with radio waves) or freeze (with cryoenergy) the abnormal tissue, instantly curing the irregular heartbeat. Deciding which to use, heat or cold, depends on where the source of arrhythmia is located. In general, cryoenergy allows us to ablate without having to worry about damage to the heart’s normal system. We’ve perfected a method of using cryoenergy to ablate, called cryoablation, with less chance of recurrence than other methods. We have an outstanding 96 percent success rate of cure. Ablation is an extremely safe and reliable solution often used to correct a too-fast heart rate.
• Medicine: Various types of medicines are used to control arrhythmia. We determine the best one for your child and use it in a safe, efficient manner to minimize side effects. When it is deemed necessary, we will monitor the effectiveness of medication with a cardiac monitoring device.
• Implantable cardioverter defibrillator (ICD): An ICD is a specialized device that can recognize a dangerous fast heart rhythm and deliver a shock to the heart to normalize the beat. ICDs save lives by preventing cardiac arrest. In older kids, the ICD is placed under the collarbone. In babies, it is placed in the abdomen. ICDs can also have pacing capabilities and can recognize a too-slow heartbeat and increase the heartbeat accordingly.
• Pacemaker: A small device placed in the body and connected to the heart with wires (leads) to monitor the heart’s electrical signals and send electrical pulses to correct an abnormal slow heartbeat.