Cardiac Rhythm and Monitors Flashcards
What portion of the heart do leads II, III, and aVF monitor? What artery?
Inferior
RCA
What portion of the heart do leads I, aVL, V5 and V6 monitor? And what artery?
Lateral
Circumflex
What portion of the heart do leads V1 and V2 monitor? What artery?
Septum
LAD
What portion of the heart do leads V3 and V4 monitor? What artery?
Anterior heart
LAD
What are 3 bipolar leads?
I, II, III
What are 3 limb leads?
aVR
aVF
aVL
In extreme right axis deviation, what is the position of lead I and Lead aVF?
Both arrows pointing down 👇
(Just think…it’s the opposite of a normal axis, which is both leads pointing up ^^)
In left axis deviation, what is the position of lead I and lead aVF?
Leaving each other in Left axis deviation
Lead I ^
Lead aVF 👇
In right axis deviation, what is the position of lead I and lead aVF?
reaching each other in right axis deviation
(like a little puzzle piece)
(Lead I 👇 but lead aVF ^)
In normal axis, what is the position of lead I and lead aVF?
Both are upright ^^
What is normal axis in degrees?
-30 to +90
What is left axis deviation in degrees?
< - 30 degrees
What are some causes of right axis deviation?
COPD
Acute Bronchospasm
Cor Pulmonale
Pulmonary hypertension
Pulmonary Embolus
What are some causes of left axis deviation?
Chronic htn
LBBB
Aortic stenosis
Aortic insufficiency
Mitral regurge
What does the mean electrical vector point towards? The hat what does it shy away from?
Towards hypertrophy
Away MI
What is a useful medication in the setting of beta-blocker overdose or calcium channel overdose?
Glucagon
What are some treatment options for afib?
Beta-blockers, calcium channel blockers, and digoxin
What is acute onset afib treated with?
Cardioversion (100 joules)
What must be performed if the onset of afib is > 48 hours?
TEE to rule out thrombus
What is the most common postoperative tachydysrhythmia?
Afib
What should hemodynamically unstable atrial flutter treated with?
Cardioversion (start at 50 joules)
What are PVCs that arise from a single location?
Unifocal
What are PVCs that arise from multiple locations?
Multifocal
What is the most common cause of sudden cardiac death?
Vfib
what is brugada syndrome?
Sodium ion channelopathy in the heart.
Common cause of nocturnal death d/t vtach/vfib
During Sinus arrhythmia, heart rate increases during what?
***Inhalation ~ decrease in intrathoracic pressure —> increase venous return —> increase heart rate
Exhalation ~ increase in intrathoracic pressure —> decrease venous return —> decrease heart rate
What reflex initiates sinus arrhythmia?
Bain ridge reflex
What is a 1st degree heart block?
PR interval > .20 sec
(AV node or bundle of his is affect)
Tx: nothing
What is a second degree heart block (type 1)?
Longer, longer, longer, and drop
PR becomes progressively longer and then drops a QRS
(AV node affected)
Tx: asymptomatic ~ monitor
Symptomatic ~ atropine
What is a 2nd degree heart block (Mobitz II)?
All the QRS have ps, but not all the ps go through resulting in a QRS.
(Affects bundle of his/BB)
Tx: pacemaker (atropine is NOT effective)
What is a 3rd degree heart block?
Ps and Qs don’t agree ~ no connection
(Degeneration of atrial conduction system)
Tx: pacemaker or isoproterenol
What do class 1 antiarrhythmic drugs inhibit?
Inhibit fast sodium channels (think lidocaine)
What do class 2 antiarrhythmic drugs inhibit?
Decrease the rate of depolarization (beta blockers)
What are class 3 antiarrhythmic agents?
Inhibit potassium ion channels (amiodarone)
What are class 4 antiarrhythmic drugs?
Inhibit slow calcium channels (CCB)
What are the common EKG characteristics in WPW?
DELTA wave
Short PR (bypass the AV)
Wide QRS complex
Possible T wave inversion
What is Orthodromic AVNRT?
(Type of WPW) Orthodromic AV nodal recently Tachycardia
More common ~ atrium —> AV node —> ventricle —> accessory pathway —> atrium
Block conduction at the AV node (vagal, cardioversion, adenosine, BB, verapamil, amiodarone)
What is antidromic AVNRT?
Antidromic AV node reentry tachy (WPW)
Atrium —> accessory pathway —> ventricle —> AV node —> atrium
Tx: cardioversion or procainamide
(AVOID: ADENOSINE, LIDO, CCBS, BBS, and DIGOXIN)
What is the definite treatment of WPW?
Ablation.
What are some conditions that prolong the QTc?
Hypokalemia
Hypomagnesemia
Hypocalcemia
What are some drugs that increase the QTc?
Methadone
Droperidol
Haloperidol
Ondansetron
Amiodarone
Quinidine
What are some cardiac conditions that increase the QTc?
Hypertrophic cardiomyopathy
Subarachnoid hemorrhage
Bradycardia
What is position 1 of n the pacemaker?
This is the chamber being paced
O: none
A: atrium
V: ventricular
D: Dual
What is position 2 of the pacemaker?
This is the chamber that is sensed
O: none
A: atrium
V: ventricle
D: Dual
What is position 3 of the pacemaker?
This is the response to the sensed native cardiac activity
T: tells the pacemaker to fire
I: tells pacemaker NOT to fire
D: if native activity is sensed ~ pacing is inhibited; if native activity is not sense ~ pacemaker fires
What is position 4 of the pacemaker?
Indicated the programmability of the pacemaker
O: none
R: rate modulation
What are examples of asynchronous pacing?
AOO, VOO, DOO
Pacemaker delivers at a constant rate
No sense/inhibition
Can result in R on T
What are examples of single-chamber demand pacing?
AAI or VVI
Back-up mode
Only fires when the native heart rates falls below a predetermined rate
What are examples of dual-chamber AV Sequential demand Pacing?
DDD
Mode is very flexible and is the most common mode of pacing.
Makes sure the atrium contracts first followed by the ventricle
Improves AV synchrony
What does placing a magnet over a pacemaker do to the pacemaker portion?
Usually converts it to an asynchronous mode
What does placing a magnet of a device due to the ICD?
Suspends the ICD and prevents shock delivery
What does placing a magnet do for a pacemaker + ICD?
Suspends the ICD and prevents shock.
Has no effect on pacemaker function
What is the only contraindication for a pacemaker or ICD?
MRI?
What are not contraindications for a Pacemaker or ICD?
Lithotripsy
Electroconvulsive therapy
Which setting of electrocautery causes more EMI?
The coagulation setting is the worst.
Which cautery causes more EMI (think bipolar vs monopolar)
Monopolar cautery
