UCLA EKG STUDYGUIDE EXAM WITH
CORRECT ACTUAL QUESTIONS AND
CORRECTLY WELL DEFINED ANSWERS
LATEST ALREADY GRADED A+ 2025 – 2026
What does NSR with 1 PJC premature junctional look like - ANSWERS-
Rhythm: Irregular
• Ventricular rate: 60
• P wave: Normal except for one absent P wave in the ectopy
• Atrial rate: 60
• Site of Pacemaker: Ectopic junctional foci for PJC
• QRS: Normal
• ST-segment: Isoelectric
• QT Interval: 0.48 seconds
Rhythm: Regular except for PJC
• Rate: Varies with underlying rhythm
• P wave: Occur "early" or "prematurely" or not present, or occurs after QRS
complex
• Site of Pacemaker: Ectopic junctional foci
,• PR Interval: Varies or absent for PJC
• QRS: Usually normal
• QT Interval: Normal
• Conduction: A "premature beat" is produced by an ectopic focus
discharging
spontaneously, causing a beat which appears earlier than expected.
• Causes: Digitalis toxicity, acute MI
• Treatment: Continue to observe
What does NSR with PVC look like? - ANSWERS-• Rhythm: Irregular
• Ventricular rate: 80
• Atrial rate: 50
• P wave: Absent in the PVCs
• Site of Pacemaker: SA node and ventricular ectopy
• PR Interval: 0.16 seconds for NSR
• QRS for PVC: 0.06 seconds for NSR
• ST-segment: Isoelectric
• QT Interval: Normal
Rhythm: Irregular due to premature beat
• Rate: Less atrial rate than ventricular rate
• P wave: Usually lost within the wide QRS complex of the PVC
• Site of Pacemaker: Besides, normal baseline rhythm, ventricular focus-
originates suddenly from an ectopic focus in the ventricles
• PR Interval: Normal but none in PVC
• QRS: Widened in PVC
, • QT Interval: Normal but not measurable in PVC
• Causes: Anxiety, excess caffeine, hypoxemia, hypokalemia,
hypomagnesemia, hypocalcemia, myocarditis, MI
• Treatment: Treat the cause
List in phases the electrophysiology of the heart - ANSWERS-Phase 0: Na+
flow in and rapid depolarization occurs
when stimulated
Phase 1: Rapid return to isoelectric level
Phase 2: Ca++ ions flow in and myocytes contract
Phase 3: K+ flow out and rapid depolarization occurs
Phase 4: Polarized resting phase
Name the three different type of heart cells - ANSWERS-Allow the heart to
integrate electrical and mechanical
activity of the heart
1. Pacemaker cells
2. Electrical conduction cells
3. Myocardial cells
What do pacemaker cells do? - ANSWERS-Pacemaker cells have the ability to
initiate an impulse
(automaticity)
CORRECT ACTUAL QUESTIONS AND
CORRECTLY WELL DEFINED ANSWERS
LATEST ALREADY GRADED A+ 2025 – 2026
What does NSR with 1 PJC premature junctional look like - ANSWERS-
Rhythm: Irregular
• Ventricular rate: 60
• P wave: Normal except for one absent P wave in the ectopy
• Atrial rate: 60
• Site of Pacemaker: Ectopic junctional foci for PJC
• QRS: Normal
• ST-segment: Isoelectric
• QT Interval: 0.48 seconds
Rhythm: Regular except for PJC
• Rate: Varies with underlying rhythm
• P wave: Occur "early" or "prematurely" or not present, or occurs after QRS
complex
• Site of Pacemaker: Ectopic junctional foci
,• PR Interval: Varies or absent for PJC
• QRS: Usually normal
• QT Interval: Normal
• Conduction: A "premature beat" is produced by an ectopic focus
discharging
spontaneously, causing a beat which appears earlier than expected.
• Causes: Digitalis toxicity, acute MI
• Treatment: Continue to observe
What does NSR with PVC look like? - ANSWERS-• Rhythm: Irregular
• Ventricular rate: 80
• Atrial rate: 50
• P wave: Absent in the PVCs
• Site of Pacemaker: SA node and ventricular ectopy
• PR Interval: 0.16 seconds for NSR
• QRS for PVC: 0.06 seconds for NSR
• ST-segment: Isoelectric
• QT Interval: Normal
Rhythm: Irregular due to premature beat
• Rate: Less atrial rate than ventricular rate
• P wave: Usually lost within the wide QRS complex of the PVC
• Site of Pacemaker: Besides, normal baseline rhythm, ventricular focus-
originates suddenly from an ectopic focus in the ventricles
• PR Interval: Normal but none in PVC
• QRS: Widened in PVC
, • QT Interval: Normal but not measurable in PVC
• Causes: Anxiety, excess caffeine, hypoxemia, hypokalemia,
hypomagnesemia, hypocalcemia, myocarditis, MI
• Treatment: Treat the cause
List in phases the electrophysiology of the heart - ANSWERS-Phase 0: Na+
flow in and rapid depolarization occurs
when stimulated
Phase 1: Rapid return to isoelectric level
Phase 2: Ca++ ions flow in and myocytes contract
Phase 3: K+ flow out and rapid depolarization occurs
Phase 4: Polarized resting phase
Name the three different type of heart cells - ANSWERS-Allow the heart to
integrate electrical and mechanical
activity of the heart
1. Pacemaker cells
2. Electrical conduction cells
3. Myocardial cells
What do pacemaker cells do? - ANSWERS-Pacemaker cells have the ability to
initiate an impulse
(automaticity)
