- QTc with Bazett's correction that is unmeasurable, or exceeds 480 msec on screening electrocardiogram (ECG); if a subject has QTc > 480 msec on screening ECG, the screen ECG may be repeated twice (at least 24 hours apart); the average QTc from the three screening ECGs must be < 480 msec in order for the subject to be eligible for the study