12 Lead EKG - Quiz 8 - THIS DECK WILL NOT HELP AT ALL - YOU WILL FAIL Flashcards
What does the EKG Record?
Electrical Activity of the Heart Beat
What is the Dominant Pacemaker of the Heart?
Sino-Atrial Node
@ SVC & RA Junction
What is Automaticity?
Ability of Cardiac Cells to spontaneously generate Action Potentials
List 1 - 9

- P
- Q
- R
- S
- T
- PR Interval
- QRS Interval
- ST Segment
- ST Interval
Slowing of depolarization at the AV node allows for what to happen?
Allows for the Atria to contract right before the Ventricles
What is the QT Interval a physiological marker for?
QT Interval represents Ventricular Depolarization & Repolarization
Risk markers for Arrythmias & Sudden Death
What are the Limb Leads on a 12-Lead EKG?
Leads I, II, III, aVF, aVR, aVL
Up-Down, Right-Left
What are the chest leads/precordial leads?
V1 - V6
Back-Front, Right-Left
What is Einthoven’s Triangle?
Triangle formed by the Limb Leads
What info can we get by looking at the multiple leads?
Region of the heart effected
What are two different ways to measure heart rate on a EKG?
- Since EKG is 10 seconds, Count QRS complex and multiply by 6
- Measure RR interval using the big boxes: 300-150-100-75-60-50
(So if its only 1 big box, then HR 300, 2 big box HR 150, and so on)

Sinus Arrhythmia
- Irregular Rhythm that varies w/ respiration
- All P-waves identical
- Considered Normal

Wandering Pacemaker
- Irregular Rhythm
- P-Waves Change Shape
- Rate < 100 bpm

Multifocal Atrial Tachycardia
- Irregular Rhythm
- P-Waves change shape
- Rate > 100 bpm

A-Fib
- Irregular Rhythms
- No P-Waves

Atrial Escape Beat

Junctional Escape Beat

Ventricular Escape Beat

Atrial Escape Rhythm
- 60-80 bpm

Junctional Escape Rhythm
or
Idiojunctional Rhythm
- 40-60 bpm

Ventricular Escape Rhythm
or
Idioventricular Rhythm
- 20-40 bpm

NSR w/ PACs

Premature Junctional Beat

Premature Ventricular Contraction

SVT
or
Paroxysmal Atrial Tachycardia
- 150-250 bpm

Ventricular Tachycardia
- 150-250 bpm

Torsades de Pointes

Ventricular Flutter
- 250-350 bpm

Ventricular Fibrillation

Sinus (SA) Block

First Degree AV Block
- PR Interval > 0.2 seconds

Second Degree AV Block - Type I
or
Wenckebach
- PR longer, longer, then drops = Wenckebach

Second Degree AV Block - Type II
- PR Constant
- Intermittent Drop QRS

3rd Degree (Complete) Heart Block
or
AV Dissociation

Left Bundle Branch Block
- Dominant S-wave in V1
- Broad “M”-shaped R-wave in V6

Right Bundle Branch Block
- Broad QRS > 0.12 sec
- RSR pattern in V1-3
- Wide, Slurred S-wave in lateral leads (I, aVL, V5-6)
What wave might you see on an EKG with Hypokalemia?
U-wave
What EKG changes would you expect with Hyperkalemia?
Tall, Peaked T-waves
When would you see a Delta wave on an EKG?
Wolf Parkinsons White Syndrome
Slurring Upstroke on QRS
What are the different phases of Coronary Artery Disease?
- Asymptomatic - insignificant plaque
- Stable Angina - known disease, collateral circulation, predictable symptoms
- Accelerating Angina - unstable plaque, unpredictable symptoms
- ACS - NSTEMI, STEMI
What happens with NSTEMIs?
- Partiall__y blocked artery
- Small portion of heart tissue dies
- Difficult to distinguish from unstable angina - need cardiac enzymes
What happens with STEMIs?
- Complete Block of Artery
- Lots of cardiac tissue dies
- Needs early intervention
How do you work up chest pain?
- Assess the kind of chest pain
- 12-Lead EKG - primary study for decision making
- Cardiac Enzymes
What are permanent markers of heart damage on an EKG?
Q Waves
More leads with abnormal Q’s = More heart damage
What is the criteria for abmnormal Q-Waves?
> 0.04 seconds wide
> 25% height of R-Wave
Permanent
How does depolarizaton happen in Left Bundle Branch Blocks?
Spreads from Right-to-Left instead of normally Left-to-Right
Impulse goes first to RV then LV
What are some causes of LBBB?
Anterior MI
Aortic Stenosis
HTN
Dilated Cardiomyopathy
Hyperkalemia
Digoxin Toxicity
What is Normal R-Wave Progression?
R waves should get bigger as you progress thru the precordial leads V1–> V6
What happens on the EKG w/ Myocardial Ischemia?
ST Segment and/or T Wave Inversion
(Can return to normal if O2 supply returns to normal)
Which lead is NOT useful and can be ignored when looking for ischemia, injury, or infarction?
aVR
What are abnormal levels of:
CK: ?
CK/MB: ?
Troponin I: ?
CK: > 170 IU/L
CK/MB: > 6 mg/mL
Trop I: > 2 ng/mL
Would Transient Myocardal Ischemia result in elevated Cardiac Markers?
There would be changes in ST-T waves, but the patient will NOT have elevated Cardiac markers b/c there is no actual heart cell damage
When would you see abnormal Q develop?
1-4 Days after STEMI
What are the Major Branches of the Coronary Arteries?
Right Coronary Artery (RCA)
Left Main Coronary Artery (LM)
Left Anterior Descending (LAD)
Circumflex Artery (CX)
Which part of the heart does the RCA supply?
Right Atrium
Right Ventricle
Posterior Wall
AV Node
PDA –> Inferior Wall
Which Leads represent the Anterior Wall?
V1-V4
Which Leads represent the Inferior Wall?
II, III, aVF
Which Leads represent the Lateral Wall?
I, aVL, V5-V6
Which Leads represent the Posterior Wall?
V1-V2
What does the Left Anterior Descending branch supply?
Anterior Wall
Septum
Left Bundle Branch
Right Bundle Branch
Papillary Muscles to Mitral Valve
What does the Left Circumflex supply?
Latereral and Posterior Left Ventricle