Effect of Interleukin-1 Blockade on Left Ventricular Systolic Performance and Work: A Post Hoc Pooled Analysis of 2 Clinical Trials

Background: Interleukin-1 (IL-1) blockade seems to improve anaerobic exercise in patients with systolic heart failure through improved left ventricular (LV) systolic performance. However, it is unclear whether IL-1 blockade affects LV systolic performance. Methods: We pooled data from 2 clinical trials of patients with systolic heart failure who were randomized to IL-1 blockade or placebo. We estimated changes in LV systolic performance (LV ejection fraction [LVEF] and end-systolic elastance [LVEes]) and pressure-volume area (PVA), a surrogate of oxygen consumption, after 14 days of treatment. Results: LVEF increased from 30% (24%-38%) to 36% (29%-43%) between baseline and day 14 only in anakinra-treated patients (P = 0.03 for within-group change and P = 0.02 for between-group change compared with placebo). LVEes increased from 1.0 mm Hg/mL (0.7-1.5) to 1.3 mm Hg/mL (0.8-1.6) in anakinra-treated patients between baseline and day 14 but not in placebo-treated patients (P = 0.03 for within-group change and P = 0.08 for between-group change). A change in PVA between baseline and 14 days was not detected in either anakinra or placebo patients. Conclusions: In this post hoc analysis, LVEes and LVEF increased significantly in patients treated with an IL-1 blocker but not in placebo-treated patients. An effect of IL-1 blockade on calculated PVA was not detected.