#1
What does the P wave represent in an electrocardiogram (ECG)?
Atrial depolarization
ExplanationAtrial depolarization is represented by the P wave in an ECG.
#2
What does the QRS complex represent in an ECG?
Ventricular depolarization
ExplanationThe QRS complex represents ventricular depolarization in an ECG.
#3
Which ECG lead is positioned at the right sternal border in the 4th intercostal space?
V1
ExplanationLead V1 is positioned at the right sternal border in the 4th intercostal space for ECG placement.
#4
Which ECG lead is commonly used to assess the lateral part of the heart?
Lead aVL
ExplanationLead aVL is commonly used to assess the lateral part of the heart in an ECG.
#5
What does the term 'cardiac axis' refer to in the context of an ECG?
Direction of electrical conduction in the heart
ExplanationIn the context of an ECG, 'cardiac axis' refers to the direction of electrical conduction in the heart.
#6
Which ECG lead is commonly used for monitoring the heart's electrical activity?
Lead II
ExplanationLead II is commonly used for monitoring the heart's electrical activity.
#7
What is the normal duration of the PR interval in an ECG?
0.12 to 0.20 seconds
ExplanationThe normal duration of the PR interval in an ECG ranges from 0.12 to 0.20 seconds.
#8
Which segment of the ECG represents the time when both ventricles are fully depolarized?
ST segment
ExplanationThe ST segment represents the time when both ventricles are fully depolarized in an ECG.
#9
What does the T wave represent in an ECG?
Ventricular repolarization
ExplanationThe T wave represents ventricular repolarization in an ECG.
#10
What is the typical duration of the QT interval on an ECG?
0.20 to 0.40 seconds
ExplanationThe typical duration of the QT interval on an ECG ranges from 0.20 to 0.40 seconds.
#11
Which condition is characterized by a prolonged QT interval on an ECG?
Long QT syndrome
ExplanationLong QT syndrome is characterized by a prolonged QT interval on an ECG.
#12
In the limb lead system, which lead represents the electrical activity between the right arm and the left leg?
Lead III
ExplanationLead III represents the electrical activity between the right arm and the left leg in the limb lead system.
#13
Which lead in the precordial (chest) leads is commonly used to assess the anterior part of the heart?
V3
ExplanationLead V3 is commonly used to assess the anterior part of the heart in the precordial leads.
#14
In the context of ECG, what does the term 'isoelectric' mean?
Constant electrical activity
ExplanationIn the context of ECG, 'isoelectric' means constant electrical activity.
#15
What is the primary function of the SA (sinoatrial) node in the heart?
Initiation of the heartbeat
ExplanationThe primary function of the SA node in the heart is the initiation of the heartbeat.