03 - Hypertrophy and Enlargement Flashcards Preview

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Flashcards in 03 - Hypertrophy and Enlargement Deck (34):
0

Enlargement vs hypertrophy

Enlargement happens when the chamber dilates to accommodate an increased amount of blood
Hypertrophy refers to an increased muscle mass

1

What is enlargement caused by?

Volume overload from aortic insufficiency or mitral regurgitation

2

What causes hypertrophy?

Pressure overload from systemic hypertension or aortic stenosis

3

Enlargement and hypertrophy cause ______ in wave duration, ______ in wave amplitude, and _____ of electrical axis

Increase - chamber takes longer to depol
Increase - chamber can generate more current
Shift - larger percentage of total current can move through expanded chamber

4

The ECG records the _________ of electrical forces at a given moment. The average vector of all of these is the _______. Its direction is called the

Instantaneous vector
Mean vector
Mean electrical axis

5

Complete depol can be represented by

Sequential vectors

6

The first vector represents ______ depol and each successive vector represents depol of the

Ventricles

7

The mean electrical axis points

Leftward and inferiorly
Represents the average during ventricular depol

8

Any mean QRS vector between -90 and +90 will produce positive QRS in

Lead I

9

Any mean QRS vector between 0 and 180 produces a positive QRS in

Lead aVF

10

If the QRS is positive in both lead I and aVF, the QRS axis lies between

0 and +90

11

With right axis deviation, the deflections will be positive in ______ and negative in ______ with the electrical axis between

aVF, lead I
+90 and 180

12

If the axis is between -90 and 180, this is called
The QRS complex will be

Extreme right axis deviation
Negative in both lead I and aVF

13

The electrical axis lies between 0 and 90 for

Left axis deviation

14

Left axis deviation has ______ aVF and ______ lead I

Negative
Positive

15

All of the information needed to assess atrial enlargement is on leads

II and V1

16

Lead II is oriented ______ to the flow of current through atria

Parallel

17

Lead V1 is oriented _______ to electrical flow

Perpendicularly

18

In right atrial enlargement, amplitude of the first portion of the P wave ______, _____ in width, and P wave axis may shift _______

Increases
No change
Rightward, beyond 90

19

Right atrial enlargement is often called

P pulmonale

20

Left atrial enlargement is called

P mitrale
Mitral valve disease is a common cause

21

The second portion of the P wave may increase in amplitude during

Left atrial enlargement
Increase in P wave duration

22

In left atrial enlargement, the terminal portion of the P wave should

Drop at least 1 mm below baseline in V1
Increase by at least .04 sec in duration

23

Causes of RVH?

Pulm HTN
Tetrology of Fallot
Pulm valve stenosis
Ventricular septal defect
Pulm disease

24

Why does RVH cause an electrical axis > 100 and right axis deviation?

It is reflective of the new electrical dominance of the usually "submissive" right ventricle

25

In RVH, lead I is slightly more

Negative than positive

26

No R wave progression
In V1, the R wave is larger than the S wave
In v6, the S wave is larger than the R wave

RVH

27

Causes of LVH?

Hypertension
Aortic stenosis
Athleticism
Hypertrophic cardiomyopathy

28

Left axis deviation in the limb leads can represent LVH but it is

Not very useful

29

Which criteria of LVH is the most accurate and sensitive?

R wave in aVL > 14 mm

These are the others:
R wave in aVF > 21 mm
R wave in lead I > 14 mm
R wave in lead I plus S wave in lead III > 25

30

In LVH, increased ____ amplitude over leads overlaying left ventricle

R wave

31

In LVH, increased _____ amplitude in leads overlying the right ventricle

S wave

32

Which criteria of LVH is the most selective and accurate?

R wave in V5 or V6 plus S wave in V1 or v2 exceeds 35 mm

Others:
R wave in V5 > 26 mm
R wave in V6 > 18 mm
R wave in V6 exceeds R wave in V5

33

Global hypertrophy can cause ______ ST segment and T wave

Downsloping
Inversion