NCMA EKG and Cardiovascular Procedures

Question 1

How many electrodes are placed on the patient for a standard 12-lead EKG?

Accepted Answer

10 electrodes (4 limb + 6 precordial)

Answer

12 electrodes (one per lead)

Answer

6 electrodes (one per precordial lead only)

Answer

8 electrodes (4 limb + 4 chest)

Question 2

Where is the V1 precordial electrode placed for a standard 12-lead EKG?

Accepted Answer

Fourth intercostal space, right sternal border

Answer

Fourth intercostal space, left sternal border

Answer

Fifth intercostal space, midclavicular line

Answer

Second intercostal space, right sternal border

Question 3

What does the P wave represent on an EKG tracing?

Accepted Answer

Atrial depolarization

Answer

Ventricular depolarization

Answer

Ventricular repolarization

Answer

Atrial repolarization

Question 4

A patient's EKG shows a heart rate of 110 bpm with regular rhythm and normal P waves before each QRS. This rhythm is classified as:

Accepted Answer

Sinus tachycardia

Answer

Atrial fibrillation

Answer

Sinus bradycardia

Answer

Ventricular tachycardia

Question 5

What is the primary reason for skin preparation before placing EKG electrodes?

Accepted Answer

To reduce skin resistance and ensure good electrical contact, reducing artifact

Answer

To mark the correct electrode placement sites on the skin

Answer

To disinfect the skin before the sterile electrode is applied

Answer

To prevent the patient from feeling pain when electrodes are removed

Question 6

What does a prolonged QT interval on an EKG indicate, and why is it clinically significant?

Accepted Answer

Prolonged ventricular repolarization; increases risk of life-threatening ventricular arrhythmias such as Torsades de Pointes

Answer

Delayed atrial conduction; can cause atrial flutter

Answer

Delayed AV node conduction; indicates first-degree heart block

Answer

Rapid ventricular repolarization; normal variant in athletes