Hypertrophy Flashcards
(23 cards)
Hypertrophy vs enlargement and what we use to refer to these
Hypertrophy = (ventricles, thicken), which is why size is effected
Enlargement = Atria (stretch out) - which is why time is effected
What are the types of hypertrophy vs enlargement
RAE
LAE
RVH
LVH
atria = enlargement
ventricle = hypertrophy
What is a normal P wave?
< 0.12 seconds (3 boxes)
<2.5 mm (2.5 boxes atrial activity is pretty small)
short and small
What leads are good indicators of a normal P waves?
Lead II (right at the mean vector)
Lead V1 (biphasic, because right atrium is towards it while left atrium is away from it)
Deviation from these
What would happen if a right atrium is larger in a P wave and why?
The first part of the p wave is indicative of the electricity from the right atrium, so it will NOT effect the time, but would rather effect the height of the p wave.
best visualized in lead II and V1
What is the criteria of RAE and rationale?
Leads to heightened amplitude of P wave > 2.5 mm (2.5 boxes in 1 inferior lead (II, III, aVF)
Just need 1 inferior lead!
Rationale: takes more voltage to depolarize a bigger right atrium
What does a lead VI look like in RAE?
First part of p wave is heightened, but negative deflection is normal
Because right atrium is affected NOT the left
What does a left atrial enlargement lead to?
A prolonged p wave that may be notched. It affects time and NOT amplitude because it takes longer to depolarize the left atrium.
What does lead VI look like in LAE?
Normal positive deflection with a prolonged negative deflection.
Because left atrium is affected NOT the right
What is the criteria for LAE?
Criteria:
P wave > 0.12 sec (3 boxes) w/ terminal portion > 0.04 sec (1 box, which is where it is notched)
Terminal portion of P wave in V1 > 1 mm below (negative
Can you have biatrial enlargement?
Yes, but must meet both criteria
What is a normal QRS net vector?
Down and to the left in the axis between 0 and 90 (4th quadrant)
What happens to the QRS segment in the pericordial leads as you go from V1 –> V6
Start mostly negative deflection at V1 and progresses to mostly positive at V6
R waves start small at v1 (because the lead is closer to the right ventricle, which does not depolarize as much) and increase at v6 (which is closer to the left ventricle, which depolarizes the most)
S wave = opposite
v1 and v2 tells us the most about the RV
v4 is the transition point
v5 and v6 tells you the most about the
What happens with RVH limb leads?
- Right axis deviation (NEEDED) negative QRS in lead 1 and aVL and positive QRS in aVF (this is because the vector is pointing AWAY and to the right instead of the left)
If you see right axis deviation, it is VERY likely this
What happens with RVH chest leads?
Instead of R wave progression, it is OPPOSITE, because it is pointing to the right instead (pointing towards limb lead 1)
Starts with big R positive wave at lead 1 and then small R wave at 6
What happens with LVH in chest leads?
Larger amplitude of R wave
Do you need to have EKG abnormalities for LVH?
NO, there can be other conditions that mask it
e.g. chest wall hypertrophy that masks the electricity
meeting the criteria though is HIGHLY suggestive of LVH
sensitive but not specific
What is the limb lead criteria for LVH? Which lead do we look at?
Limb Lead Criteria:
The R-wave amplitude in lead aVL exceeds 11 mm (11 boxes) (lead 1 will be increased as well)
same vector as normal (because it is typically is the whole LV) just larger
Left axis deviation
What is the chest lead criteria for LVH?
Chest Lead Criteria:
The R-wave amplitude in lead V5 or V6(positive) plusthe S wave amplitude in lead V1 or V2 (negative) exceeds 35 mm
What is the combined criteria for LVH that is used to make sure there is not displacement?
The R-wave amplitude in aVL plus the S-wave amplitude in V3 exceeds 20 in women and 28 in men
The more criteria they meet, the more likely they have LVH
Don’t need to memorize this
What are downfalls of ventricular hypertrophy criteria?
Not accurate in <35 yo (because some have stronger hearts)
If there is LVH with repolarization then there is concern and you should get an echo
Does ventricular hypertrophy effect amplitude, timing, or both?
Only amplitude (still fast)
What are secondary repolarization abnormalities d/t ventricular hypertrophy?
Can lead to downsloping (linear) ST segment depression
T-wave inversion
seen in both right (V1 V2) and left (lead 1 AVL, V5, V6)
This can cause false readings for ischemia
