- Heart failure (HF) with preserved ejection fraction (HFpEF) is a clinical condition characterized by large pathophysiology heterogeneity with lack of effective therapies as proven by the disappointing results generated by randomized controlled trials. - The TOPCAT trial and its design have been previously described in detail, as have its main results.The trial was an international, multicenter, double-blinded, randomized clinical trial of the aldosterone antagonist spironolactone for patients with HFpEF, defined as symptomatic HF at the time of screening and within the preceding 12 months in patients with a left ventricular EF of 45% or greater.