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