141-171 Flashcards
In 3rd degree AV block we can find __ wave moving at - bpm, but bearing no relationship to the __ complexes.
P
60-100
QRS
What are the 3 criteria for RBBB?
- QRS>0.12 (wide)
- RSR’ in V1 and V2 (rabbit ears)+ST depression + T -wave inversion
- Reciprocal changes in V5, V6, I, and aVL
What are the 4 criteria for LBBB?
- QRS>0.12 (wide)
- Broad/notched R wave + prolonged upstroke in V5, V6, I, and aVL with ST depression and T-wave inversion
- Reciprocal changes in V1 and V2
- Left axis deviation may be present
BBB is diagnosed by looking at the width and configuration of the ___ complexes
QRS
_BBB is fairly common in otherwise normal hearts
R
_BBB rarely occurs in normal hearts
L
The term hemiblock refers to a conduction block of just one of which fascicles?
septal/left anterior/left posterior
Hemiblock applies only to _BBB
L
Hemiblocks cause ___
axis deviation
Left anterior hemiblock cause __ axis deviation between - degrees
left
-30 and -90
Left posterior hemiblock cause __ axis deviation
right
The QRS complex in hemiblocks is __, and there are no __ segment or __ wave changes
normal
ST
T
Which type of hemiblock is more common?
Left anterior
What does the term bifascicular block refers to?
The combination of either left anterior or left posterior hemiblock with RBBB
What are the 3 criteria for bifasicular block?
- QRS > 0.12 seconds
- RSR’ in V1 and V2
- Left axis deviation between -30 and -90
What is an incomplete BBB?
left/right BBB with rabbit ears in V1, but QRS is between 0.10-0.12 seconds
How do you call the bypass pathway in Wolff Parkinson White syndrome?
bundle of Kent
WPW criteria: X3
- PR interval <0.12 (less than 3 small cubes)
- wide QRS complexes
- Delta wave
What is the reason for wide QRS in WPW?
premature ventricular activation
What are the 4 stages of MI seen on an ECG?
- T-wave peaking
- T- wave inversion
- ST-segment elevation
- formation of Q wave
In MI T waves inversion will persist for __ to __
months to years
In MI T-waves are inverted in a __ fasion
symmetric
Inferior infraction is often caused by occlusion of the __ coronary artery. It can be seen in leads ,,_.
right
II
III
aVF
Lateral infraction is often caused by occlusion of the __ circumflex coronary artery. It can be seen in leads ,,,.
left I aVL V5 V6
Anterior infraction is often caused by occlusion of the __ coronary artery. It can be seen in leads leads -
LAD
V1-6
Posterior infraction is often caused by occlusion of the __ coronary artery. It can be seen by looking at__changes in the anterior leads, especially in __.
right
reciprocal
V1
Which area of the heart does it involve?
- Inferior infraction?
- lateral infraction?
- anterior infraction?
- posterior infraction?
- diaphragmatic surface
- left lateral wall
- anterior surface of the left ventricle
- posterior surface
Hyperkalemia will show __ waves peaking, __ interval prolongation, flattening of the __ wave and ultimately the __ complex widens until it merges with the T wave- forming __ wave pattern
T PR P QRS sine
What are the 4 changes seen in an ECG of a patient with hypokalemia?
- ST-segment depression
- flattening of the T wave
- prolongation of the QT interval
- U waves
Hypercalcemia __ the QT interval, while hypocalcemia __ it. Remember that QT prolongation may lead to __
prolongs
shortens
Torsade de pointes
What are the 8 steps when reading an ECG?
- heart rate
- intervals
- axis
- rhythm
- AV blocks (AV/BBB/hemi)
- preexcitation
- enlargement and hypertrophy
- coronary artery disease
