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- Böhm, Michael, et al.
(författare)
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Heart rate as a risk factor in chronic heart failure (SHIFT): the association between heart rate and outcomes in a randomised placebo-controlled trial
- 2010
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Ingår i: Lancet. - 0140-6736. ; 376:9744, s. 886-894
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Raised resting heart rate is a marker of cardiovascular risk. We postulated that heart rate is also a risk factor for cardiovascular events in heart failure. In the SHIFT trial, patients with chronic heart failure were treated with the selective heart-rate-lowering agent ivabradine. We aimed to test our hypothesis by investigating the association between heart rate and events in this patient population. METHODS: We analysed cardiovascular outcomes in the placebo (n=3264) and ivabradine groups (n=3241) of this randomised trial, divided by quintiles of baseline heart rate in the placebo group. The primary composite endpoint was cardiovascular death or hospital admission for worsening heart failure. In the ivabradine group, heart rate achieved at 28 days was also analysed in relation to subsequent outcomes. Analysis adjusted to change in heart rate was used to study heart-rate reduction as mechanism for risk reduction by ivabradine directly. FINDINGS: In the placebo group, patients with the highest heart rates (>or=87 beats per min [bpm], n=682, 286 events) were at more than two-fold higher risk for the primary composite endpoint than were patients with the lowest heart rates (70 to <72 bpm, n=461, 92 events; hazard ratio [HR] 2.34, 95% CI 1.84-2.98, p<0.0001). Risk of primary composite endpoint events increased by 3% with every beat increase from baseline heart rate and 16% for every 5-bpm increase. In the ivabradine group, there was a direct association between heart rate achieved at 28 days and subsequent cardiac outcomes. Patients with heart rates lower than 60 bpm at 28 days on treatment had fewer primary composite endpoint events during the study (n=1192; event rate 17.4%, 95% CI 15.3-19.6) than did patients with higher heart rates. The effect of ivabradine is accounted for by heart-rate reduction, as shown by the neutralisation of the treatment effect after adjustment for change of heart rate at 28 days (HR 0.95, 0.85-1.06, p=0.352). INTERPRETATION: Our analysis confirms that high heart rate is a risk factor in heart failure. Selective lowering of heart rates with ivabradine improves cardiovascular outcomes. Heart rate is an important target for treatment of heart failure. FUNDING: Servier, France.
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| 2. |
- Swedberg, Karl, 1944, et al.
(författare)
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Ivabradine and outcomes in chronic heart failure (SHIFT): a randomised placebo-controlled study
- 2010
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Ingår i: Lancet. - 0140-6736. ; 376:9744, s. 875-885
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Chronic heart failure is associated with high mortality and morbidity. Raised resting heart rate is a risk factor for adverse outcomes. We aimed to assess the effect of heart-rate reduction by the selective sinus-node inhibitor ivabradine on outcomes in heart failure. METHODS: Patients were eligible for participation in this randomised, double-blind, placebo-controlled, parallel-group study if they had symptomatic heart failure and a left-ventricular ejection fraction of 35% or lower, were in sinus rhythm with heart rate 70 beats per min or higher, had been admitted to hospital for heart failure within the previous year, and were on stable background treatment including a beta blocker if tolerated. Patients were randomly assigned by computer-generated allocation schedule to ivabradine titrated to a maximum of 7.5 mg twice daily or matching placebo. Patients and investigators were masked to treatment allocation. The primary endpoint was the composite of cardiovascular death or hospital admission for worsening heart failure. Analysis was by intention to treat. This trial is registered, number ISRCTN70429960. FINDINGS: 6558 patients were randomly assigned to treatment groups (3268 ivabradine, 3290 placebo). Data were available for analysis for 3241 patients in the ivabradine group and 3264 patients allocated placebo. Median follow-up was 22.9 (IQR 18-28) months. 793 (24%) patients in the ivabradine group and 937 (29%) of those taking placebo had a primary endpoint event (HR 0.82, 95% CI 0.75-0.90, p<0.0001). The effects were driven mainly by hospital admissions for worsening heart failure (672 [21%] placebo vs 514 [16%] ivabradine; HR 0.74, 0.66-0.83; p<0.0001) and deaths due to heart failure (151 [5%] vs 113 [3%]; HR 0.74, 0.58-0.94, p=0.014). Fewer serious adverse events occurred in the ivabradine group (3388 events) than in the placebo group (3847; p=0.025). 150 (5%) of ivabradine patients had symptomatic bradycardia compared with 32 (1%) of the placebo group (p<0.0001). Visual side-effects (phosphenes) were reported by 89 (3%) of patients on ivabradine and 17 (1%) on placebo (p<0.0001). INTERPRETATION: Our results support the importance of heart-rate reduction with ivabradine for improvement of clinical outcomes in heart failure and confirm the important role of heart rate in the pathophysiology of this disorder. FUNDING: Servier, France.
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