Pharmacotherapy for diastolic HF improves symptoms but not mortality
MedWire News: Pharmacologic therapy for diastolic heart failure (DHF) is associated with an improvement in exercise tolerance but not in mortality, a meta-analysis has found.
The finding contrasts with the established efficacy of pharmacotherapy in systolic HF and may reflect the greater comorbidity burden in patients with DHF, according to the study authors.
The meta-analysis was undertaken by Thomas Marwick (Cleveland Clinic Heart and Vascular Institute, Ohio, USA) and colleagues, and aimed to bring together all available evidence from trials of pharmacologic treatment for DHF (also known as HF with a preserved ejection fraction).
"We hypothesized that since previous studies have been neutral, combining them might bring a different result for treatment effects not only on mortality but also on exercise tolerance and diastolic function," they explain in the Journal of the American College of Cardiology.
A literature search identified 18 randomized controlled trials (n=11,253) and 12 observational studies (n=42,625). Many different agents were tested in these trials, including both monotherapies and drug combinations, with either placebo or diuretic acting as control.
In the randomized trials, combined therapy did not reduce mortality (relative risk [RR]=0.99) or diastolic function (quantified by transmitral flow, E/A ratio, weighted mean difference [MD]=-0.01) but did significantly improve exercise tolerance (assessed by treadmill time, MD=51.5).
In the observational studies, combined therapy reduced all-cause mortality in unadjusted analyses (RR=0.80) but not after adjusting for clinical and demographic characteristics (RR=0.93). Individual treatment (with either beta-blockers or renin-angiotensin-aldosterone system blockers) also had no effect on adjusted mortality.
Marwick's team concludes that, in contrast to systolic HF, treatment options for patients with HF with a preserved ejection fraction remain unproven.
"Current recommendations support the treatment of underlying etiologies, although the associated benefits of these therapies on hard endpoints are anticipated rather than proven in this group," they write.
"As patients with HF with a preserved ejection fraction are often older than their systolic HF counterparts, improvement in symptoms, rather than reduction of mortality, may present more important and pragmatic outcomes."
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By Joanna Lyford