Abstract

Background Resistant hypertension is a salt-retaining condition possibly attributable to inappropriate aldosterone secretion. Methods and Results This study was a secondary analysis of the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist) trial. Patients with heart failure with preserved ejection fraction (HFpEF) with (n=1004) and without (n=2437) resistant hypertension were included. Resistant hypertension was defined as systolic blood pressure ≥130 mm Hg and/or diastolic blood pressure ≥80 mm Hg in a patient with hypertension, despite the concurrent use of a renin-angiotensin system blocker (angiotensin-converting enzyme inhibitor/angiotensin receptor blocker), a calcium channel blocker, and a diuretic; or as those patients using ≥4 classes of antihypertensive medication. The primary outcome was a composite of cardiovascular death, aborted cardiac arrest, or heart failure hospitalization. We analyzed hazard ratios (HRs) for outcomes with 95% CIs in the spironolactone group and compared them with the placebo group using Cox proportional hazard models. The risk of primary outcome events in patients with HFpEF with resistant hypertension was significantly lower in the spironolactone group than in the placebo group (HR, 0.70; 95% CI, 0.53-0.91; <i>P</i>=0.009), whereas the risk of primary outcome events in patients with HFpEF without resistant hypertension was not significantly different between the 2 groups (HR, 1.00; 95% CI, 0.83-1.20; <i>P</i>=0.97). There was a significant interaction between spironolactone use and resistant hypertension (<i>P</i>=0.03). Similar associations were also observed in patients with HFpEF from the Americas (United States, Canada, Brazil, and Argentina) only. Conclusions Spironolactone may be an effective add-on medication for patients with HFpEF with resistant hypertension taking angiotensin-converting enzyme inhibitors/angiotensin receptor blockers, calcium channel blockers, and diuretics.