2026 QUESTIONS WITH ANSWERS GRADED
A+
◉ AV Node. Answer: - back up pacemaker of the heart
- expected rate: 40-60 bpm
◉ ventricles. Answer: - final pacemaker (backup) of the heart)
- expected rate: <40 bpm
◉ P wave. Answer: - waveform: shown as upright in lead II
- represents atrial depolarization
◉ PR interval (PRI). Answer: - duration: 0.12-0.2 seconds (3-5 little
boxes)
- represents signal from SA to AV nodes
◉ QRS complex. Answer: - duration: 0.04-0.12 seconds (1-3 little
boxes)
- represents ventricular depolarization
, ◉ QT interval (QTI). Answer: - duration: 0.36-0.44 seconds (about 2 big
boxes)
- represents ventricular depolarization and repolarization (contracting
and relaxing)
◉ ST segment. Answer: - returns to isoelectric baseline
- represents early ventricular repolarization
◉ T wave. Answer: - shown as upright in lead II
- shows ventricular repolarization
◉ QTc. Answer: >500msec or QTc increase 15%-20% over baseline
problematic for TDP
◉ determining the HR. Answer: - count the amount of R waves in 6
seconds (30 big boxes) -> then multiply by 10
◉ 300 block method. Answer: - 300/amount of big blocks between R-R
waves
- sequence: 300, 150, 100, 75 , 60, 50, 43, 37
◉ sinus rhythm. Answer: