- Patients with a history of a cardiovascular illness including but not confined to: CHF (grade III or IV NYHA); a history of angina pectoris within the previous year; history of any cardiac arrhythmia; QTc prolongation as determined by Bazett's formula and defined as QTc interval >480 msec (including patients on medication which may prolong QTc), or history of myocardial infarction within one year of study enrollment