#1
What does the P wave represent in an ECG?
Atrial depolarization
ExplanationRepresents the electrical depolarization of the atria.
#2
Which segment of the ECG represents ventricular depolarization?
QRS complex
ExplanationElectrical activity as the ventricles contract.
#3
What is the normal heart rate range for an adult at rest?
60-100 beats per minute
ExplanationTypical range indicating normal cardiac function.
#4
Which wave in the ECG represents ventricular repolarization?
T wave
ExplanationRecovery phase of ventricular cells.
#5
Which lead placement is typically used to record a standard 12-lead ECG?
Lead I, II, III, aVR, aVL, and aVF
ExplanationStandard leads for comprehensive cardiac monitoring.
#6
What is the normal duration of the PR interval in milliseconds?
0.12 to 0.20 seconds
ExplanationNormal time for atrial depolarization to ventricular depolarization.
#7
Which of the following arrhythmias is characterized by chaotic, irregular atrial activity on ECG?
Atrial fibrillation
ExplanationIrregular atrial contractions leading to ineffective pumping.
#8
Which ECG lead is typically used to diagnose an inferior myocardial infarction?
Lead aVF
ExplanationFocuses on the inferior wall of the heart, sensitive to changes.
#9
Which electrolyte imbalance is associated with a prolonged QT interval on ECG?
Hypokalemia
ExplanationLow potassium levels affecting cardiac repolarization.
#10
What does a prolonged PR interval suggest on an ECG?
First-degree heart block
ExplanationDelayed conduction from atria to ventricles.
#11
What does a 'sawtooth' pattern of flutter waves typically indicate on an ECG?
Atrial flutter
ExplanationRapid regular atrial contractions, distinct from fibrillation.
#12
What is the characteristic appearance of a QRS complex in a ventricular premature contraction (PVC)?
Broad and bizarre
ExplanationAbnormal ventricular depolarization pattern.
#13
What is the most common cause of peaked T waves on an ECG?
Hyperkalemia
ExplanationHigh potassium levels affecting repolarization.
#14
What is the characteristic ECG finding in ventricular fibrillation?
Chaotic rhythm with no discernible waves
ExplanationComplete disorganization of cardiac electrical activity.
#15
What is the most common cause of a widened QRS complex on ECG?
Bundle branch block
ExplanationImpaired conduction in the heart's electrical pathways.
#16
Which arrhythmia is characterized by a regular rhythm with a wide QRS complex and absence of P waves?
Ventricular tachycardia
ExplanationAbnormal rapid heart rhythm originating in the ventricles.