Hawthorn Extract Randomized Blinded Chronic Heart Failure (HERB CHF) Trial

Inclusion Criteria:

Ambulatory individuals 18 years and older who had been diagnosed with CHF (NYHA functional classes II-IV) for > 3 months
Left ventricular ejection fraction (LVEF) of ≤ 40 percent
Receiving indicated standard therapy (if not contraindicated or intolerant for > 3 months) defined as a diuretic, an ACE-inhibitor or an angiotensin receptor blocker (ARB) and a beta-blocke
Patients with NYHA class III or IV symptoms were also required to receive spironolactone. Doses of these drugs had to be stable for ≥ 3 months, except for diuretics, for which ≥ 1 month of stability was required.

Exclusion Criteria:

Hemodynamically severe uncorrected primary valvular disease
Active myocarditis
Hypertrophic cardiomyopathy
Restrictive cardiomyopathy
Myocardial infarction, stroke, unstable angina, coronary artery bypass graft surgery, valvular surgery, or angioplasty < 3 months before randomization
Symptomatic or sustained ventricular tachycardia not controlled by antiarrhythmic drugs or an implantable cardioverter-defibrillator
Any condition other than heart failure that would be expected to limit exercise (e.g., angina, peripheral vascular disease, pulmonary disease, arthritis, or an orthopedic problem severe enough to limit exercise)
Nursing mothers, pregnant women and those planning a pregnancy during the study period