Complementary Alternative Cardiovascular Medicine

38 Alternative Cardiovascular Medicine
extract compared to placebo in a 3-mo randomized, double-blind, placebo-controlled
trial of 88 patients with NYHA stage II CHF (69).
The German Commission E recognized hawthorn for the treatment of
mild CHF. However, at this time, hawthorn should be seen primarily as
an adjunctive therapy for all but the mildest cases of CHF, because a
clear reduction in morbidity and mortality has been seen with the use of
angiotensin-converting enzyme (ACE) inhibitors, which should remain,
if appropriate, a first-line treatment for CHF.
Hawthorn’s flowers, leaves, and berries often find their way into
antihypertensive formulas. It has been postulated that the mild hypotensive
activity of hawthorn may result from inhibition of ACE (70). Ex
vivo studies indicate that the flavonoids induce endothelium-dependent
NO-mediated relaxation (71).
However, reductions in systolic and diastolic blood pressures in
humans are small with the use of hawthorn (67,72). Therefore, hawthorn
should not relied on as a sole therapy for hypertension treatment.
Herbalists typically combine hawthorn with a diuretic agent (i.e., dandelion
leaf), a nervine (i.e., valerian), and peripheral vasodilators (i.e.,
ginger). Because this type of individualized combination therapy has not
been subjected to randomized trials, its efficacy is unknown.
Hawthorn reduces cholesterol in rabbits that were fed a high-cholesterol
diet (73,74). The study by Zhang et al. (73) found that hawthorn
fruit does not affect the activities of HMG-CoA reductase or cholesterol
7-alpha-hydroxylase (CH) but does suppress the activity of intestinal
acyl CoA:cholesterol acyltransferase (ACAT) (p < 0.05). The authors
conclude that the lipid-lowering effects of hawthorn may, in part, result
from the inhibition of cholesterol absorption mediated by downregulation
of intestinal ACAT activity.
Although hawthorn is often found in dietary supplements that are
designed to reduce cholesterol, there are no human clinical trials available
to determine if the fruit, leaves, or flowers lower lipids humans, and,
if they do, to what extent and at what dose.
The dose typically given for hawthorn leaf with flower is 2.0–3.5 g/d
as an infusion or decoction or equivalent dose in tincture. Standardized
extracts are also available and generally provide 30–168.7 mg
procyanidins, calculated as epicatechin, or 3.5–19.8 mg flavonoids,
calculated as hyperoside taken in two or three individual doses (19). The
majority of studies have been conducted on two distinct preparations of
hawthorn. Special extract WS 1442 (Dr. Willmar Schwabe Pharmaceuticals)
contains 80 mg hawthorn leaf with a 5/1 (w/w) dry flower extract
standardized to 18.75% oligomeric procyanidins (15 mg) per capsule.