arrhythmias Flashcards
aterial cells fire occasionally from a focus
premature atrial contraction (PACs)
atrial cells fire continuously due to a looping re entrant circuit
atrial flutter
re-enter pathway occurs when
an impulse loops and results in self perpetuating impulse formation
atrial cells fire continuously from multiple foci or fire continuously due to multiple micro re-entrant ‘wavelets’
atrial fibrillation
The AV junction fire continuously due to a looping re entrant circuit
proximal supravetricular tachycardia
The AV junction block impulses coming from the SA node
AV junctional blocks
ventricular cells fire occasionally from one or more foci
premature ventricular contractions(PVCs)
ventricular cells fire continuously from multiple foci
ventricular fibrillation
ventricular cells fire continuously due to a looping re-entrant circuit
ventricular tachycardia
HR <60 bpm
SA node is depolarizing slower than normal ,impulse is conducted normally(normal PR and QRS interval)
bradycardia
HR >100 bpm
SA is depolarizing faster than normal ,impulse is conducted normally
sinus tachycardia
sinus………. is a response to physical or psychological stress , not a primary arrhytmia
sinus tachycardia
premature atrial contractions ,these ectopic originates in ……………………
in the atria but not in the SA node
when an impulse originates anywhere in the atria (SA node ,atrial cells , AV node , bundle of his ) and then conducted normally through the ventricles, the QRS will be …………….
narrow (0.04-0.12s)
when ectopic beats originate in the ventricles resulting in …………………….QRS complexes.
wide and bizarre
the 12 leads include :
-3 limb leads (I,II,III)
-3 AUGMENTED LEADS (aVR,aVL,aVF)
-6 PRECORDIAL LEADS (V1-V6)
how we can diagnose of an acute MI
-elevation of the ST segment(greater than one small box)(transmural or Q-wave )
-Non-ST elevation (subendocardial or non-Q-wave)
The anterior portion of the heart is best viewed with which leads ?
V1-V4
if you see changes in V1-V4 with a myocardial infarction , you can conclude that it is an …………………..
an anterior wall myocardial infarction
the leads II,III and aVF see electrical activity moving from which side of heart?
inferiorly
the leads I and aVL see electrical moving from which side of heart ?
left
which leads see electrical activity in the posterior to anterior direction of heart ?
precordial leads
what leads the lateral portion of the heart is best viewed ?
leads I,aVL,and V5-V6
what leads best viewed the inferior portion of heart?
leads II,III,aVF
when myocardial blood supply is abruptly reduced or cut off to a region of the heart a sequence of injurious events occurs name them?
1.ischemia (inadequate tissue perfusion )
2.necrosis (infarction)
3.fibrosis scarring)
what are the change in ECG in ischemiain ST elevation in MI?
ST depression, peaked T-waves, then T-wave inversion
what are the changes in the ECG in the infarction(necrosis) in ST elevation of MI?
ST elevation&appearance of Q-waves
what are the changes in the ECG in the fibrosis in ST elevation of MI?
ST segments and T-waves return to normal, but Q-waves persist
what are the changes in ECG in ischemia in non-ST elevation infarction ?
ST depression & T-wave inversion
what are the changes in ECG in infarction(necrosis) in non-ST elevation infarction
ST depression & T-wave inversion
what are the changed in ECG in fibrosis in non-ST elevation infarction ?
ST returns to baseline, but T-wave inversion persists
depolarizationof the bundle branches and parking fibers are seen as the ……………. wave on the ECG.
QRS COMPLEX
with bundle branch blocks you will see which change on ECG?
1.QRS complex widens(>0.12s)
2.QRS morphology changes
why does the QRS complex widen ?
when the conduction pathway is blocked it will take longer for the electrical signal to pass throughout the ventricles
what QRS morphology is characteristic of right bundle branch blocks?
for RBBBB the wide QRS complex assumes a unique , virtually diagnostic shape in those leads overlying the right ventricle(V1-V2)
the rabbit ears IN ECG show what?
RBBB(right bundle branch block)
