1-100 Flashcards
Bundle-branch block typically features
discordant ST-T-wave changes, meaning that the ST segment and T wave are directed opposite the major polarity of the QRS complex. In leads with positive QRS complexes, ST-segment depression and T-wave inversion are expected, and in leads with a primarily negative QRS complex, ST-segment elevation and an upright T wave are anticipated.
Fascicular blocks
do not significantly prolong the qrs complex duration but rare important because they can cause changes that mimic previous infarction and in certain circumstances identify patients at greater risk to develop DC
the left bundle branch splits into two fascicles, two
fascicular blocks are possible: the more common Left anterior ; and the relatively rare left posterior
TABLE 2.1. Causes of intraventricular conduction abnormalities
Atherosclerotic heart disease Congenital heart disease Connective tissue disease (eg, scleroderma; electrolyte abnormalities, fibrotic heart disease, latrogenic, infectious disease, inflitrative cardiomyopathy; PE; normal variant toxicologic
describe normal QRS complex: Consider the two precordial electrodes, V1 and V6 as being essentially
opposite each otehr in the horizontal plane in a vector representatino of ventricular depolarization
Also remember that a waveform; eg a Q an R or an S wave is positive if the depolarization vector is coming toward the electrode.
lead V1; demonstrates a small R wave followed by a large S wave
lead v6 ; a small initial Q wave; septal Q wave; followed by a large R wave
causes of R wave amplitude greater than S wave amplitude in lead V1
hypertrophic cardiomyopathy
normal variant especially children and adolescents
duchenne type pseudohypertrophic muscular dystrophy
PH
RBBB
RVH
true posterior MI
WPWS
a general rule: recognition of dominant R wave in lead V1 should prompt consideration of RBBB
criteria RBBB?
- in V6; small initial Q wave from the septum; then signifcant R wave, then wide S wave from delayed depolarization of the RV
criteria LBBB?
slurred monophasic R wave in V5-6 can be absent, but present in leads I and aVL
linker hartas is not a prerequisite for diagnosis but can occur with it ; more often it is however normal
if it is really negative; -90, that suggest preexisting or coincident left anterior fascicular block
in leads with a predominantly positive QRS complex, the ST segments and T waves are isoelectric or depressed; and vise versa, the transition leads in which the overall QRS complex is neutral do not necessarily follow this pattern;;;; deviation from this can suggest MI
dd large amplitude negative QS or rS complexes in leads V1 and V2 (right precordial leads)
criteria left anterior fascicular block
linker hartas is belangrijk; more liberal definition starts with -30, but in general -45
once left axis is noted, the next step focuses on analysis of the limb leads not the precordial leads
IMPORTANT; a key finding is poor precordial R wave progression or displacement of the transition zone
LVH should not be diagnosed by aVL R wave amplitude higher than 11 mm in the presence of this condition because R wave in lead aVL is bigger than normal
this abnormality is the most common intraventricular conduction abnormality seen in acute MI
left posterior fascicular block
type of bradycardias
escape pacemaker rhythms
heart blocks
AV blocks
third av block rest
causes of clinically significant av block
mobitz 1 vs 2
third degree AV block
narrow complex tachycardias
mechanisms of tachyarrhythimas
focal atrial tachyacardia caused by enhanced automaticity
multifocal atrial tachycardia
characteristics AF
characterisitics atrial flutter
nonparoxysmal junctional tachycardia
characteristics atrioventricular AVNRT
characteristics atrioventricular AVRT
how to diagnose narrow complex tachycardias
causes wide complex tachycardia
supraventriculr causes of wide complex tachycardia
causes of wide complex tachycardia foto explanatino
ventricular causes of wide QRC complex tachycardia
wide QRC complex tachycardia regular vs irregular
criteria VT
stemi location
reciprocoal st segment depressions according to the area of infarction
criteria wellens syndrome
Q-wave equivalents in the precordial leads
dd pathologic Q waves
when should you do additional lead ECGs in emergency department?
sgarbossa criteria
smith modified sgarbossa criteria
de winter pattern
wellens forms
st eleveation mimics
how to distinguish between MI and left ventricular aneurysm?
describe st segments in pericarditits?
describe early repolarization?
what is afro caribbean pattern ?
pharmacologic causes of st segment elevation
what is spiked helmet
what is spiked helmet shape
pulmonolagy pathology?
causes of st segment depressions
physiological j junctional depression with sinus rhythm
foto physiological j junctional depression with sinus rhythm
secondary st-t wave repolarization abnormality
causes of t wave flattening
causes of t wave inversions
causes of biphasic t wave
causes of tall t wave
causes of t wave notching
causes pericarditits
symptoms pericarditits
common ecg findings in pericarditits
stages pericarditits
which questions should you ask in pericarditits?
symptoms myocarditis
common ecg findings in myocarditits
ecg findings in pericardial effusion and tamponade
ecg WPW
avrt subtypes
key points brugada syndrome
key points hypertrophic cardiomyopathy
key points long QT syndrome
key points right ventricular cardiomyopathy
congenital arrhythmic syndromes
types of Brugada syndrome
suggestive of hypertrophic cardiomyopathy
criteria for diagnosis of arrhthmogenic right ventricular cardiomyopathy
nongenetic causes of QTc prolongation
Long QT syndrome diagnostic criteria
findings in potassium abnormalities
key points hypothermia
key points thoracic aortic disseaction
key points pneumothorax
key points PE
key points COPD
keypoints central nervous system events
hypothermia findings
PE details
thoracic aortic disseaction rhythm morphology
pneumothorax left vs right
copd rhythm morphology
findings cholecystitis; intestinal obstruction; pancreatititis
common sodium channel lblockers
medications that cause bradycardia
medications that cause tachycardia
medications that cause potassium rectifier current inhibition
drugs that cause hyper and hypo kalemia
RVH criteria
not all need to be met
LVH criteria in children
not all need to be met
right atrial enlargement in children
not all need to be met
left atrial enlargement in children
not all need to be met
how to distinugish RBBB vs RVH
both might show q R variant
hartas >110, right atrial enlargement, S wave larger than 0.7 mv in lead V6, R:S ratio <1 in V5-6; all of this favor RVH
how to distinguish RBBB vs. acute MI
ST-segment and T wave changes in RBBB are, in V1-3, opposite to the overall direction the QRS (depression and t wave inversion); no other segments are affected
in MI you see ST segement elevations in V1-3
