In patients with chronic heart failure, the addition of aliskiren to enalapril led to more adverse events without an increase in benefit. There was a higher risk of hypotensive symptoms in the combination-therapy group than in the enalapril group (13.8% vs. 11.0%, p=0.005), as well as higher risks of an elevated serum creatinine level (4.1% vs. 2.7%, p=0.009) and an elevated potassium level (17.1% vs. 12.5%, p<0.001).