Frequency and predictors of hyperkalemia in patients <GT>=60 years of age with heart failure undergoing intense medical therapy. - Muzzarelli S; Maeder MT; Toggweiler S; Rickli H; Nietlispach F; Julius B; Burkard T; Pfisterer ME; Brunner-La Rocca HP; TIME-CHF Investigators (American Journal of Cardiology, 2012)