Pfeffer M & Eugene Braunwald E. JAMA Cardiol. Published online February 24, 2016. doi:10.1001/jamacardio.2015.0356
"Heart failure (HF) with preserved ejection fraction (HFpEF) is a syndrome that occurs in about one-half of all patients with HF and is being recognized with increasing frequency. Although its specific causes have not been elucidated in the majority of patients, HFpEF occurs most commonly in elderly individuals who have 1 or more comorbidities that include hypertension, obesity, diabetes, metabolic syndrome, atrial fibrillation, anemia, and chronic kidney disease. While by its usual definition the left ventricular ejection fraction is 45% or more (and in some instances ≥50%), HFpEF may also be characterized by diastolic dysfunction that impairs ventricular filling resulting from slowed ventricular relaxation and an increase in passive ventricular stiffness. In some patients with HFpEF, this elevation in filling pressure is manifest only during exercise, whereas in others it is more sustained, and results in pulmonary hypertension...
Based on this rationale and the public health burden resulting from HFpEF, the National Heart, Lung, and Blood Institute initiated the Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist (TOPCAT) trial...
From a strictly statistical point of view, the results of TOPCAT must be regarded as neutral. However, HFpEF is often a disabling and life-shortening condition. Other than the administration of diuretics for fluid accumulation and the management of hypertension (if present), there is little to offer these patients. Based on the findings in TOPCAT in North and South America and in the absence of other more definitive data, it now appears reasonable to treat patients with HFpEF resembling those enrolled in North and South America with spironolactone to improve outcomes. This drug is generic, inexpensive, and generally well tolerated, although periodic monitoring of electrolytes and creatinine must be conducted to detect the occasional development of hyperkalemia and renal dysfunction."