The hyperkalemic Brugada sign

BackgroundA few case reports have indicated that hyperkalemia can induce a Brugada pattern in the electrocardiogram. The specific clinical and electrocardiographic features of the hyperkalemic Brugada sign, however, have not been previously described.MethodsA case series was collected from hospitalized hyperkalemic patients with a type I Brugada pattern in the electrocardiogram, and a literature review was performed. Electrocardiograms were examined for rhythm and morphology, and clinical characteristics were analyzed.ResultsNine new cases with the hyperkalemic Brugada sign were identified with an additional 15 cases found in the literature. Of the 9 cases, 8 were male patients, and all were critically ill; 5 of the 9 died within 48 hours. The mean (±SD) serum potassium level was 7.8 ± 0.5 mEq/L. The mean QRS width was 144 ± 31 milliseconds, and all had abnormal QRS axis. In 6 cases, there was a wide complex rhythm without visible P waves. The clinical and electrocardiographic characteristics of 15 cases found in the literature were remarkably similar to those in our series.ConclusionsThe hyperkalemic Brugada pattern differs in substantial ways from the electrocardiogram of patients with the genetic Brugada syndrome. Many patients have wide complex rhythms without visible P waves, marked QRS widening, and an abnormal QRS axis. Most patients are male, and many are critically ill. Prompt recognition of this clinical and electrocardiographic entity may expedite the initiation of appropriate treatment for hyperkalemia.