Fragmented QRS – a new predictor of prognosis in Brugada Syndrome

Multiple spikes within the QRS is known as fragmented QRS (f-QRS). Morita et al, from Okayama, Japan has found an association between f-QRS and ventricular fibrillation in Brugada Syndrome (Circulation. 2008;118:1697-1704). 115 patients were evaluated – 13 resuscitated from ventricular fibrillation, 28 with syncope and 74 asymptomatic. 43% of them had f-QRS. The highest occurrence was in the group with ventricular fibrillation (85%) while the lowest was in the asymptomatic individuals (34%; P<0.01). Those with f-QRS were more likely to have SCN5A mutations (33% in those with f-QRS vs 5% in those without f-QRS). In the group with ventricular fibrillation or syncope, only 6% without f-QRS had VF during follow up while 58% with f-QRS had recurrent syncope due to ventricular fibrillation (P<0.01). The authors go on to recommend implantation of an ICD (implantable cardioverter defibrillator) in Brugada Syndrome patients who experienced syncope without detected ventricular fibrillation, but have f-QRS as they are at increased risk for a subsequent arrhythmic event. In those with prior ventricular fibrillation, f-QRS indicates a risk of recurrent ventricular fibrillation including arrhythmic storm.