A pathological change of the cardiac conduction system causes a heart rhythm disturbance. Most affected do not experience symptoms, while others suffer from sudden loss of consciousness or a cardiac still-stand. Sudden cardiac death can occur as early as in the teenage years. The cause of Brugada syndrome is most often due to a primarily electrical condition stemming from a mutation of the gene SCN51. Mutations of this gene lead to a disturbance in the sodium channel, causing dysregulation of the influx and efflux of sodium. This leads to a disturbance in the depolarization/repolarization of the cardiac cells, putting those affected at risk for an arrhythmia.
Brugada syndrome can, sooner or later, lead to Ventricular Fibrillation, which can only be treated with a defibrillator, applied externally or internally. A defibrillator is typically implanted in those who have already experienced fatal arrhythmias or loss of consciousness. The defibrillator monitors the heart’s function and, when needed, automatically delivers a shock to return the heart’s pump function to its normal state.
There are two main types of implantable cardioverter-defibrillators (ICD): transvenous and subcutaneous.
A transvenous ICD is a device approximately the size of a matchbox, which is implanted in the chest area, with a lead running through a vein to connect it with the internal heart. A subcutaneous ICD is implanted below the axilla (armpit) with the lead running under the skin along the sternum. It is also able to shock the heart when a life-threatening rhythm is detected, without any direct contact to the heart or blood vessels.
Those who suffer from Brugada Syndrome can be helped temporarily with medications. A few cases have also tried ablation of certain areas of the heart muscle in an attempt to avoid dangerous arrhythmias.