EDITOR—The study reported by Verhamme et al has several noteworthy limitations.1 Firstly, the mortality benefit conferred by spironolactone therapy in heart failure has been shown only among patients with severe disease2 and hence, as the authors acknowledged, such patients are far more likely to be prescribed this therapy than patients with, for example, relatively asymptomatic echocardiographic evidence of impaired left ventricular function. Given …