EKG: Enlargement and Hypertrophy

Question 1

Most hypertrophy is caused by _____

Answer 1

pressure overload
○ Pressure overload occurs with conditions like Aortic Stenosis, HTN, etc

Question 2

The term _____ refers to dilation
of a particular cardiac chamber.

Answer 2

“Enlargement”

Question 3

The term _____ refers to an increase in muscle mass.

Answer 3

“Hypertrophy”

Question 4

Most cases of enlargement are caused by
_____

Answer 4

volume overload
○ Volume overload can occur with CHF,
various valvular disorders, and congenital heart defects

Question 5

T/F enlargement and hypertrophy can coexist in the same patient

Answer 5

T

Question 6

There are three possible changes that may occur on an EKG when a chamber
of the heart hypertrophies or enlarges. These include:

Answer 6

○ Increased Wave Duration - The chamber wall can take longer to depolarize.
○ Increased Wave Amplitude - The chamber wall can generate more current, and thus a larger voltage.
○ Axis Deviation - A larger percentage of the total electrical current can move through the abnormal chamber, shifting the direction of the mean electrical vector and deviating the axis.

Question 7

To assess the atria for enlargement, we examine the _____

Answer 7

P waves

Question 8

When studying for evidence of atrial enlargement, pretty much all of the
information we need can be gathered from leads ____

Answer 8

II and V1.

Question 9

____ is oriented nearly parallel to the
normal mean P wave vector, and
therefore records the largest positive
deflection of atrial depolarization.

Answer 9

Lead II

Question 10

_____ is oriented perpendicular to the
normal mean P wave vector, and therefore
is biphasic, allowing for easy separation of
right and left atrial depolarization

Answer 10

Lead V1

Question 11

With right atrial enlargement, the amplitude of the first portion of the P wave ____

Answer 11

increases

Question 12

The presence of _____ is characteristic and
diagnostic of right atrial enlargement

Answer 12

P waves with an amplitude exceeding 2.5
mm in the inferior leads (II, III, or AVF)

Question 13

The classic picture of Right Atrial Enlargement

Answer 13

Tall P waves in the inferior leads (look at lead II first), and a dominant right atrial component of the biphasic P wave in lead V1.

Question 14

Because of the strong association between right atrial enlargement and severe lung disease (like late stage COPD), these EKG findings are often called _____

Answer 14

“P Pulmonale.”

Question 15

With left atrial enlargement, the amplitude of the second portion of the P wave ____

Answer 15

increases.

Question 16

Left atrial enlargement EKG manifestations

Answer 16

● This manifests primarily in Lead V1 in two important ways
○ Increased negative amplitude in the terminal
component of the P wave, descending at least 1 mm below the isoelectric line in V1.
○ The duration of the P wave increases in general, and the terminal negative portion of the P wave must be at least 1 mm (0.04 seconds) in width.

Question 17

you may
also see an M-like appearance of the P wave in Lead II with ____

Answer 17

LAE

Question 18

Because left atrial
enlargement is commonly
caused by mitral valve
disease, these EKG
findings are commonly
called _____

Answer 18

“P Mitrale.”

Question 19

T/F ventricular hypertrophy cannot be diagnosed if there
is a BBB.

Answer 19

T

Question 20

Additional evidence of right ventricular hypertrophy can
be obtained by looking at the _____

Answer 20

precordial leads
○ In Lead V1, the R wave is larger than the S wave.
○ In Lead V6, the S wave is larger than the R wave

Question 21

Right ventricular hypertrophy often
occurs in congenital heart disease and
severe pulmonary disease, and it is
commonly seen along with ____

Answer 21

right atrial enlargement

Question 22

not considered a
specific indicator for diagnosis of LVH.

Answer 22

LAD (though it may be seen)

Question 23

The most common criteria for LVH used is the Sokolow Criteria:

Answer 23

○ The S wave amplitude in V1 or V2 plus the R wave amplitude in V5 or V6
(whichever is tallest) exceeds 35 mm

Question 24

In the presence of ventricular hypertrophy, these abnormalities include:

Answer 24

○ Downsloping ST Segment Depression
○ T Wave Inversion (no longer same direction as QRS)