Clinical Question: Is hawthorn extract an effective treatment for patients with chronic heart failure?
Setting: Outpatient (any)
Study Design: Meta-analysis (randomized controlled trials)
Synopsis: The authors of this meta-analysis identified 13 trials that evaluated the effectiveness of extract from the hawthorn leaf (Crataegus monogyna or Crataegus laevigata) in the treatment of patients with heart failure. The authors independently searched a number of databases (including herbal databases), hand-searched relevant journals, and checked bibliographies of identified articles to find the randomized studies included in this analysis. They also translated articles published in other languages.
Eight of the studies evaluated the effect of hawthorn extract on maximal workload, and five studies evaluated the effect on symptoms. Most of the studies used hawthorn extract without standard therapy or with limited treatment (diuretics). The daily dosages ranged from 160 mg to 1,800 mg, usually using a product standardized to 18.8 percent oligomeric procyanidins.
Maximal workload was significantly improved in patients who used hawthorn extract when compared with those who used placebo (weighted mean difference = 7 watts, 95 percent confidence interval, 3 to 11 watts). In four of the studies that evaluated symptoms, there was more improvement with hawthorn extract therapy than with placebo (results could not be combined). Two studies that used the same symptom score showed a significant improvement in symptoms with hawthorn extract compared with placebo (n = 169). Adverse events were generally mild and transient. Dizziness was the most common adverse effect, reported in eight patients in the the eight studies.
Bottom Line: The herbal product hawthorn extract, which has prescription-only status in Germany, has positive inotropic activity and improves symptom scores in patients with heart failure. Currently, there are no data about whether it has any impact on mortality rates. The most effective dosage is also not known. Although hawthorn extract should not replace standard therapy for heart failure, patients may add it to existing therapy if they wish. (Level of Evidence: 1a–)
Used with permission from Shaughnessy AF. Herbal treatment for chronic heart failure. Retrieved July 24, 2003, from: www.InfoPOEMs.com.