Which of the following is QT interval?: (A) A, (B) B, (C) C, (D) D
Answer is B. Ans. (b) QT intervalPR interval (A)120-200msec and represents spread of impulse from SAN to AV nodeRR interval (C)Inversely related to heart rateQT interval (B)400-430 msec and represents ventricular depolarization and repolarization.