- Patients with ECG results of any conduction delays (PR interval > 200 ms, corrected QT [QTC] > 480 ms), sinus bradycardia (resting heart rate < 50 beats per minute), sinus tachycardia (heart rate >120 beats per minute) will be evaluated by a cardiologist prior to starting the trial; patients with any arrhythmias, including atrial fibrillation/atrial flutter, excessive ectopy (defined as > 20 premature ventricular contractions [PVCs] per minute), ventricular tachycardia or 3rd degree heart block will be excluded from the study unless cleared by a cardiologist