SCRIPT 2026 QUESTIONS WITH
SOLUTIONS GRADED A+
◍ Normal Sinus.
Answer: 60-100 bpm0.12 - 0.20 sec PR intervalQRS <0.12
◍ Sinus Brady.
Answer: Same as sinus with <60 BPM
◍ Which pathway depolarizes the left atrium?
A. Thorel tract
B. Bachman bundle
C. Kent bundle
D. Wenckebach tract.
Answer: B. Bachman. Bundle There are 3 internodal tracts that travel from
the SA to AV node:1. Anterior internodal tract (gives rise to Bachmann
bundle)2. Middle internodal tract (Wenckebach tract)3. Posterior internodal
tract (Thorel tract)
◍ Sinus Tachycardia.
Answer: Sinus with rate of 100-160 BPM
◍ Sinus Pause, Arrest, Block.
Answer: Sinus followed by a break without electrical activity
◍ Premature Atrial Complex (PAC).
Answer: Early beat, QRS is "Skinny"Comes from an irritable place in the
atrium
◍ Conduction velocities if cardiac conduction pathway from slowest to
fastest:.
, Answer: AV nodeSA node Myocardial muscle cellsHIS bundle Bundle
branches Purkinje fibers
◍ Atrial Tachycardia / Supraventricular Tachycardia (SVT).
Answer: Regular rhythm, rate 160-200 BPM, normal QRSP wave may or
may not be present
◍ Atrial Fibrillation (A-Fib).
Answer: Irregularly irregular, QRS <0.12 sec, Wavy baseline
◍ Atrial Flutter (A-Flutter).
Answer: Usually regular, QRS <0.12, saw tooth P-waves
◍ Match each phase of the ventricular action potential to its corresponding
component on the EKG waveform: Phase 0Phase 2Phase 3T wave QT
interval QRS complex.
Answer: Phase 0- QRSphase 2- QT interval Phase 3- T wave There are 5
phases of ventricular action potential: 0= rapid depolarization (QRS) - Na
IN1= initial repolarization(QRS) - Cl in/K+ OUT2= plateau phase (QT
interval)-Ca IN/K out3= final repolarization (T wave)- K+ OUT4= resting
phase (T to QRS)- K+ leak
◍ Key components of the EKG:.
Answer: P wave- atrial depolarization begins PR interval- atrial
depolarization complete QRS- atrial repolarization + ventricular
depolarization ST segment- ventricular depolarization complete T wave-
ventricular repolarization begins
◍ Match each disease with the EKG abnormality that it is most likely to cause:
Hypokalemia WPWPericarditis Intracranial hemorrhage PR interval
depression U wave Peaked T wave Delta wave.
Answer: Hypokalemia- U wave WPW- Delta wave Pericarditis- PR interval
depression Intracranial hemorrhage- Peaked T wave
◍ Q waves suggest myocardial infarction if:.
Answer: Amplitude is greater than 1/3 of R wave Duration is greater than
0.04 secsDepth is greater than 1mm