#1
Which of the following is NOT a standard limb lead in a 12-lead ECG?
Lead IV
ExplanationLead IV is not a standard limb lead; leads I, II, and III are.
#2
What is the purpose of placing electrodes for a 12-lead ECG?
To measure electrical activity of the heart from different angles
ExplanationElectrodes are positioned to capture cardiac electrical signals from various perspectives.
#3
Which of the following is the standard placement for the right arm electrode in a 12-lead ECG?
Fourth intercostal space, right sternal border
ExplanationThe right arm electrode is typically positioned at the fourth intercostal space, right sternal border.
#4
What does the P-wave represent in an ECG?
Atrial depolarization
ExplanationThe P-wave signifies atrial depolarization.
#5
In a 12-lead ECG, where is the electrode placed for Lead aVR?
On the right arm
ExplanationThe electrode for Lead aVR is positioned on the right arm.
#6
Which of the following chest leads typically corresponds to the fifth intercostal space at the left midclavicular line?
Lead V4
ExplanationLead V4 is placed at the fifth intercostal space, left midclavicular line.
#7
In which lead of a 12-lead ECG would you expect to see the most positive deflection for a typical QRS complex?
Lead II
ExplanationLead II commonly displays the most positive QRS complex deflection.
#8
Which lead serves as the 'ground' lead in a standard 12-lead ECG?
Lead aVR
ExplanationLead aVR functions as the 'ground' lead in a standard 12-lead ECG.
#9
What does the ST segment represent in an ECG?
Isoelectric period between ventricular depolarization and repolarization
ExplanationThe ST segment reflects the period between ventricular depolarization and repolarization, where the line is isoelectric.
#10
Which lead is considered reciprocal to Lead III in a 12-lead ECG?
Lead aVF
ExplanationLead aVF is reciprocal to Lead III in a 12-lead ECG.
#11
In the standard limb leads, which electrode placement serves as the reference point (zero potential)?
Right leg
ExplanationThe right leg electrode serves as the reference point in standard limb leads.
#12
Which lead is often used to monitor the inferior wall of the left ventricle?
Lead aVF
ExplanationLead aVF is frequently employed to assess the inferior wall of the left ventricle.
#13
Which of the following is NOT typically measured directly from the ECG?
Blood pressure
ExplanationBlood pressure is not typically directly measured from an ECG.
#14
In Lead V6 of a 12-lead ECG, where is the electrode typically placed?
Fifth intercostal space, left midaxillary line
ExplanationThe electrode for Lead V6 is typically placed at the fifth intercostal space, left midaxillary line.
#15
In Lead V3 of a 12-lead ECG, where is the electrode typically placed?
Between V2 and V4
ExplanationThe electrode for Lead V3 is typically placed between V2 and V4.