6.6, 6.6a - 6.6g, and 6.7 - Precordial Leads, Wilson's Central Terminal, and Precordial Vector Views

Precordial leads use the ____________ plane to view the heart:

Transverse (horizontal)

How do precordial leads differ from limb leads in terms of perspective?

They view the heart from the transverse plane rather than the coronal plane

The transverse plane divides the heart into which two halves?

A top half and a bottom half

Precordial leads allow ECG recordings from which perspectives?

Front-to-back and side-to-side

Another name for precordial leads is ____________ leads:

Chest

How many precordial leads are used in an ECG?

Six

The six precordial leads are labeled ____________ through ____________:

V1 through V6

The letter "V" in precordial leads stands for ____________:

Vector

Where are precordial electrodes placed to obtain an accurate ECG?

On specific locations on the chest

Why is it important to place precordial leads in defined locations?

To ensure an accurate ECG recording

Who was the first to describe using a central point of reference for unipolar potentials?

Frank Norman Wilson and his colleagues

Wilson called the central point of reference the ____________:

Central terminal

Wilson’s theory found that the average potential over the body could be approximated by ____________:

The potential average of the three limb leads

By using this central terminal, the body becomes the ____________ pole:

Negative

All six precordial leads are considered ____________ unipolar leads:

Positive

How do precordial leads measure electrical impulses?

In only one direction

By adding the six unipolar leads to the limb leads, what could be accurately determined?

A three-dimensional picture of the heart’s electrical activity

Who was the first to use the letter "V" for the six unipolar chest leads?

Frank Norman Wilson

The letter "V" in precordial leads stands for ____________:

Vector

What numbers are used to label the six unipolar chest leads?

1–6

How many leads are used in a normal ECG?

12

Which precordial lead is the only one placed on the right side of the chest?

V1

Lead V1 is positioned on the __________ side of the sternum in the __________ intercostal space:

Right, fourth

What anatomical structure does lead V1 primarily provide a transverse plane view of?

The interventricular septum

Lead V2 is placed on the __________ side of the sternum in the fourth intercostal space:

Left

The V2 electrode is positioned __________ of the V1 electrode:

Opposite

Lead V2 provides another transverse plane view of the __________:

Interventricular septum

Where is lead V3 placed in relation to leads V2 and V4?

Halfway between them

Lead V3 provides a transverse plane view of the __________ wall of the __________ ventricle:

Anterior, left

Lead V4 is positioned in the __________ intercostal space along the __________ line:

Fifth, midclavicular

What part of the heart does lead V4 provide a view of?

The anterior wall of the left ventricle

Lead V5 is positioned in the fifth intercostal space at the __________ line:

Left anterior axillary

Lead V5 provides a view of the __________ wall of the __________ ventricle:

Lower lateral, left

Where is lead V6 placed on the chest?

At the midaxillary line

Which three leads are positioned in the fifth intercostal space?

V4, V5, and V6

Lead V6 provides a view of the __________ wall of the __________ ventricle:

Lower lateral, left

What plane is used to show all precordial views?

The transverse plane

The concept of __________ in the coronal plane can also be applied to the transverse plane:

Vectors

Using a __________, the precordial leads can be mapped in the transverse plane:

Circle

What do the precordial leads provide a picture of?

The direction of the electrical impulses of the heart during one cardiac cycle