EXAM CURRENT FOR 2026/2027 PRACTICE QUESTIONS
AND STUDY GUIDE COMPLETE ACCURATE EXAM ACTUAL
QUESTIONS AND CORRECT VERIFIED ANSWERS WITH
DETAILED RATIONALES (RELIABLE SOLUTIONS) A NEW
UPDATED VERSION 2026 EDITION ||JUST RELEASED
What is the P wave?
atrial depolarization (contraction)
First upward deflection
Represents Atrial Depolarization (contraction)
Usually followed by QRS
,What is the PR interval?
Time impulse takes to move through atria and AV node (time needed
for atrial depolarization/contraction). “The time between atrial
depolarization & ventricular depolarization”
From beginning of P wave to next deflection on the baseline
(beginning of QRS complex)
Length: 0.12 – 0.20 sec (3 to 5 small boxes)
,What is the QRS wave?
Composition of 3 Waves
Represents Ventricular Depolarization (contraction)
Much variability
Length: < 0.12 sec (less than 3 small boxes)
Q- first negative depolarization of the complex (may or may not be
present)
R – first positive upward deflection following the P wave
S – first negative deflection following R wave
What is the ST segment?
Early repolarization of ventricles
Measured from J point to onset of T wave
Elevation or depression may indicate abnormality (possible MI)
Length: nonspecific. (we do not measure the ST segment, we monitor
where it falls)
, What is the T wave?
Repolarization of ventricles
Concurrent with end of ventricular systole
May become tented (peaked) in hyperkalemia
Length: nonspecific
Remember when potassium is high T wave is taller and when K is low
an U wave will appear. T is taller than u