EKG: Enlargement and Hypertrophy Flashcards
Most hypertrophy is caused by _____
pressure overload
○ Pressure overload occurs with conditions like Aortic Stenosis, HTN, etc
The term _____ refers to dilation
of a particular cardiac chamber.
“Enlargement”
The term _____ refers to an increase in muscle mass.
“Hypertrophy”
Most cases of enlargement are caused by
_____
volume overload
○ Volume overload can occur with CHF,
various valvular disorders, and congenital heart defects
T/F enlargement and hypertrophy can coexist in the same patient
T
There are three possible changes that may occur on an EKG when a chamber
of the heart hypertrophies or enlarges. These include:
○ 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.
To assess the atria for enlargement, we examine the _____
P waves
When studying for evidence of atrial enlargement, pretty much all of the
information we need can be gathered from leads ____
II and V1.
____ is oriented nearly parallel to the
normal mean P wave vector, and
therefore records the largest positive
deflection of atrial depolarization.
Lead II
_____ is oriented perpendicular to the
normal mean P wave vector, and therefore
is biphasic, allowing for easy separation of
right and left atrial depolarization
Lead V1
With right atrial enlargement, the amplitude of the first portion of the P wave ____
increases
The presence of _____ is characteristic and
diagnostic of right atrial enlargement
P waves with an amplitude exceeding 2.5
mm in the inferior leads (II, III, or AVF)
The classic picture of Right Atrial Enlargement
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.
Because of the strong association between right atrial enlargement and severe lung disease (like late stage COPD), these EKG findings are often called _____
“P Pulmonale.”
With left atrial enlargement, the amplitude of the second portion of the P wave ____
increases.
Left atrial enlargement EKG manifestations
● 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.
you may
also see an M-like appearance of the P wave in Lead II with ____
LAE
Because left atrial
enlargement is commonly
caused by mitral valve
disease, these EKG
findings are commonly
called _____
“P Mitrale.”
T/F ventricular hypertrophy cannot be diagnosed if there
is a BBB.
T
Additional evidence of right ventricular hypertrophy can
be obtained by looking at the _____
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
Right ventricular hypertrophy often
occurs in congenital heart disease and
severe pulmonary disease, and it is
commonly seen along with ____
right atrial enlargement
not considered a
specific indicator for diagnosis of LVH.
LAD (though it may be seen)
The most common criteria for LVH used is the Sokolow Criteria:
○ The S wave amplitude in V1 or V2 plus the R wave amplitude in V5 or V6
(whichever is tallest) exceeds 35 mm
In the presence of ventricular hypertrophy, these abnormalities include:
○ Downsloping ST Segment Depression
○ T Wave Inversion (no longer same direction as QRS)
