Cardiac complications in pediatric patients on the ketogenic diet.

Cardiac complications of the ketogenic diet, in the absence of selenium deficiency, have not been reported. Twenty patients on the ketogenic diet at one institution were investigated. Prolonged QT interval (QTc) was found in 3 patients (15%). There was a significant correlation between prolonged QTc and both low serum bicarbonate and high beta-hydroxybutyrate. In addition, three patients had evidence of cardiac chamber enlargement. One patient with severe dilated cardiomyopathy and prolonged QTc normalized when the diet was discontinued.