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C HAPTER 41 / Complementary and Alternative Approaches in Cardiovascular Disease 913
There are special concerns related to cardiac patients and tolerance, and reduce subjective symptoms in patients with
herbal remedies. Cardiac conditions generally require clinical sur- NYHA class II heart failure. 31,32 Tauchert 33 reported that WS
veillance by a licensed care provider. It is unwise for patients with 1442, when combined with diuretics, improved exercise tolerance
heart failure to self-medicate, whether for cardiac or noncardiac and reduced symptoms in patients with NYHA class III heart fail-
conditions. Herbal products can alter drug absorption. For exam- ure. When patients treated with hawthorn extract (900 mg/day;
ple, guar gum and psyllium reduce absorption of some pharma- LI 132) were compared with those treated with captopril (37.5 mg/
ceutical or herbal remedies. Some herbal remedies are associated day), both groups increased their maximal exercise significantly
with drug interactions. For example, several herbs increase the and similarly. 33
bleeding risk for patients taking anticoagulants. Bleeding has been There could be risks if hawthorn is taken in conjunction with
reported with the use of gingko biloba, garlic, and the Chinese drugs and herbs containing cardiac glycosides (i.e., digoxin prepa-
herbs danshen and dong quai. rations, black hellebore, Canadian hemp root, digitalis leaf, hedge
One compound merits special comment related to potential mustard, figwort, lily of the valley roots, motherwort, oleander
adverse cardiac effects. Aconite (sometimes called “chuanwu” or leaf, pheasant’s eye plant, pleurisy root, squill bulb leaf scales, stro-
“caowu”) is used in TCM to treat neuromuscular and arthritic- phanthus seeds), since the effects could be additive. There have
related pain conditions. Aconite contains diterpenoid alkaloids, been reports of interactions with anticoagulants and antihyper-
which are toxic to neurons and to the heart. Fatal cardiac ar- tensives. Other botanical products with potential cardioactive
rhythmias (bradycardia, hypotension, ventricular tachycardia, properties include calamus, cereus, cola, coltsfoot, devil’s claw,
supraventricular tachycardia, bidirectional tachycardia, heart European mistletoe, fenugreek, fumitory, ginger, Panax ginseng,
block, torsade de pointes) have been reported with the herb. Theres s white horehound, mate, parsley, quassia, scotch broom flower,
is no known antidote. Atropine may be helpful if there are brad- shepherd’s purse, and wild carrot. Hawthorn taken in combina-
yarrhythmias. Electrical cardioversion tends not to work in tion with these or with cardioactive drugs could amplify or coun-
aconite poisoning. teract the activity of those herbs or drugs. However, Daniele
Two herbal remedies commonly prescribed today in heart fail- et al. 34 completed a systematic review of the adverse events asso-
ure include Crataegus oxyacantha (hawthorn) and Terminalia ar- ciated with hawthorn and concluded that the products are rela-
juna. Although both of these products appear relatively safe and tively safe. Side effects reported include gastrointestinal symp-
somewhat effective, self-medication poses risk for interactions toms, dizziness, sleep problems, fatigue, rash (particularly on the
w
with conventional clinical management paradigms. hands), and palpitations. According to the Cochrane Review, no
data are available related to mortality or cardiac-related morbidity:
Hawthorn no rigorous trials have monitored long-term outcomes such as car-
Hawthorn (also known as maybush, maythorn, or may; the for- diac death, nonfatal myocardial infarction, and hospitalization.
a
a
mal name is C. oxyacantha) is traditionally used as a cardiac tonic.
The German Commission E approves use of hawthorn leaf and T. arjuna Tree Bark
flower extracts for patients with New York Heart Association The bark of the T. arjuna tree (sometimes called Indian al-
(NYHA) class II heart failure. Hawthorn has been recommended mond) has been used in India as a cardiac tonic for more than
to treat angina, hypertension, hypotension, arrhythmias, heart 3,000 years. Its stem bark possesses glycosides, flavonoids, tan-
failure, hyperlipidemia, atherosclerosis, and gastrointestinal symp- nins, and minerals (calcium, magnesium, zinc). Glycosides have
toms. A poultice of the hawthorn fruit is sometimes used to treat a positive inotropic effect. Flavonoids have antioxidant, anti-in-
skin lesions. flammatory, and lipid-lowering effects. T. arjuna has been used
A Cochrane Systematic Revieww 30 summarizes a meta-analysis of to treat coronary artery disease, angina, heart failure, and hy-
w
the evidence relating to the therapeutic efficacy of hawthorn ex- percholesterolemia. It has sometimes been used as an antibac-
tracts in heart failure. In 14 trials hawthorn was used, generally as terial, antimutagen, or aphrodisiac. Related products made
an adjunct to conventional clinical management of patients with from the fruit of Terminalia chebula and Terminalia belerica are
NYHA classes I to III. Hawthorn extracts compared favorably used in AM as a “health harmonizer” or to balance the vital hu-
with placebo in that treated patients demonstrated increased exer- mors. No large-scale, long-term, well-controlled studies of the
cise tolerance. Pressure-rate product (an index of myocardial oxy- efficacy of T. arjuna in cardiac disease have been published, but
gen consumption) decreased, indicating improvement. Shortness there are many small studies. Dwivedi and Agarwal 35 con-
of breath and fatigue improved with hawthorn treatment com- ducted small clinical trials in patients with angina, comparing
pared with placebo. usual care (in this case, nitrates, aspirin, and/or a calcium chan-
Hawthorn preparations have positive inotropic effect on the nel blockers) with and without powdered T. arjuna bark for
myocardium. This is likely due to phosphodiesterase inhibition 3 months. Patients receiving T. arjuna bark experienced less
activity (similar to amrinone, milrinone). However, because the angina compared with patients receiving the usual care. 35,36 In
myocardial cell refractory period is lengthened with hawthorn, another small study, patients with severe refractory congestive
preparations are antiarrhythmic (unlike other phosphodiesterase heart failure (treated with digitalis, diuretics, vasodilators) had
inhibitors which are typically proarrhythmic). Hawthorn prepara- reduced symptoms and improved left ventricular function when
tions reduce peripheral vascular resistance (i.e., afterload), possibly T. arjuna was added to the treatment regimen. 37 Studies are
the reason that myocardial oxygen consumption is reduced. Other needed analyzing the efficacy of T. arjuna in combination with
clinical actions attributed to hawthorn include increased coronary more recently recommended conventional regimens with
blood flow and reduced lipid levels; it has been suggested to have demonstrated efficacy in heart failure (i.e., -blockers, an-
antibacterial, spasmolytic, and analgesic effects. Several studies giotensin-converting enzyme inhibitors). The mechanism of
have demonstrated that standardized leaf and flower extracts action for T. arjuna is not known. The herb is thought to be rel-
(known as LI 132 or WS 1442) improve ejection fraction, exercise atively safe, but it may increase blood pressure.