For people at high risk of ventricular arrhythmias , maintaining high-normal potassium levels resulted in improved outcomes in a new randomized controlled trial of 1,200 people with implanted cardioverter defibrillators (ICDs) . The results of the trial are published in the New England Journal of Medicine . The study, conducted at three sites in Denmark, was called the POTCAST trial, for “Targeted Potassium Levels to Decrease Arrhythmia Burden in High-Risk Patients with Cardiovascular Diseases.”