What is QT QTc normal range?
What is QT QTc normal range? Definitions of normal QTc vary from being equal to or less than 0.40 s (≤ 400 ms), 0.41 s (≤ 410 ms), 0.42 s (≤ 420 ms) or 0.44 s (≤ 440 ms). For risk of sudden cardiac death, "borderline QTc" in males is 431–450 ms; and, in females, 451–470 ms. What is the difference between QT and QTc in ECG? Generally, QT intervals are corrected for heart rate so that QTc is equal to QT if the heart rate is 60 beats per minute, i.e., RR interval of 1 s. What is normal...