August 29th, 2010
Downshifting Heart Rate in HF Found Beneficial
In the SHIFT trial, Karl Swedberg and colleagues tested the effects of ivabradine, a selective sinus-node inhibitor, in 6558 patients with heart failure who had a heart rate ≥70 bpm. After a median 23 months of follow-up, the rate of cardiovascular death or hospital admission for worsening heart failure was 24% in the ivabradine group and 29% in the placebo group (hazard ratio, 0.82; 95% CI 0.75–0.90, P<0.0001). The results were presented at the ESC in Stockholm and published simultaneously in the Lancet.
In an accompanying comment in the Lancet, John Teerlink noted that many patients in SHIFT did not receive optimal medical therapy, especially high-dose beta-blockers. Therefore, he writes: “Whether ivabradine can improve outcomes in addition to optimally managed heart failure therapies or its benefits relative to other therapies, especially beta blockers, remains unknown.”
In a second paper published in the Lancet, Michael Böhm and colleagues analyzed data from SHIFT and found that in the placebo group, patients with heart rates in the highest quintile at baseline had double the risk of patients in the lowest quintile. In the placebo group, the investigators observed a direct correlation between heart rate at 28 days and subsequent outcome, and concluded that “the effect of ivabradine is accounted for by heart-rate reduction.”