Cardiac Output Autonomic Stimulation Therapy for Heart Failure - Hemodynamic Effects

Inclusion Criteria: * Normal sinus rhythm by ECG * Men and women 21-75 years old * Patients with stable symptomatic heart failure, New York Heart Association (NYHA) class II, III, or IV. Exclusion Criteria: * Systolic Blood Pressure \< 90 mmHg or \> 160 mmHg * Current amiodarone therapy or any other antiarrhythmic therapy * Coronary artery bypass graft surgery or percutaneous coronary intervention within prior 1 month * Enzyme-positive MI within prior 1 month * Patients who have been hospitalized for heart failure and who required the use of HF IV therapy within 30 days before enrollment (measured from release) * History of recent severe ventricular arrhythmias * Pre-existing carotid artery or cerebral disease * Patients with hypertrophic obstructive cardiomyopathy or infiltrative cardiomyopathy (e.g. amyloidosis, sarcoidosis) * Patients with prior vagalotomy * Patients with current or prior vagal nerve stimulators * Subjects with narrow angle glaucoma * Renal failure - on dialysis or serum creatinine \> 2.0 mg/dl * Hepatic failure - bilirubin, SGOT, or SGPT \> 4X upper limit of normal * Patients with a life expectance \< 12 months per physician judgment * Women who are pregnant * Allergy to fentanyl, midazolam, propofol, eggs, egg products, soybeans, or soy products * Subjects unwilling or unable to provide consent for the protocol