Spironolactone Initiation Registry Randomized Interventional Trial in Heart Failure with Preserved Ejection Fraction (SPIRRIT-HFpEF) is a pragmatic, registry-based randomized clinical trial that proposes to evaluate the clinical effectiveness of spironolactone versus usual care. The primary hypothesis of SPIRRIT- HFpEF is that treatment with spironolactone will reduce cardiovascular mortality compared with usual care.