Body surface electrodes record heart's electrical activity. Electrodes have positive or negative polarity. Paper speed is 25 millimeters per second. Small box (1mm) traversed in .04 seconds, large box (5mm) in .2 seconds
VFib is a dangerous heart rhythm that stops blood pumping. Electrical signals in heart go haywire, causing ventricles to quiver. Without treatment, it's fatal within 3-5 minutes. Most common cause of sudden cardiac death
PR interval measures electrical delay between atrial and ventricular contractions. Normal PR interval ranges from 0.12 to 0.20 seconds. Each small box on EKG strip represents 0.04 seconds
First wireless EKG monitor invented by Polar Electro in 1977 for Finnish ski team. Consumer monitors started retail sales in 1983 with wireless technology
QT interval measures heart's electrical characteristics from Q to T wave. Lead II is most commonly used for QT measurement. Bazett's formula corrects QT using heart rate and QRS interval
Platform offers practice drills, quizzes, coaching and reference guides. Practice tests provide interactive multiple-choice interpretation with immediate feedback. Quizzes include over 50 categories for different healthcare professionals. Training modules cover EKG basics and rhythm analysis