6 - EKG #2 Flashcards
What are the learning objectives?
1) Recognize three different classes of tachyarrhythmias in both the atria and ventricles (paroxysmal tachycardia, flutter and fibrillation) on an EKG
2) Recognize first, second and third-degree AV blocks on an EKG
3) List medications (or other factors) that can potentiate the above arrhythmias
4) Develop a systematic approach to analyzing lead 2 of an EKG
At rest:
150 - 250 bpm indicates what?
paroxysmal tachycardia
At rest:
250-350 bpm indicates what?
tachycardia flutter
At rest:
350 - 450 bpm indicates what?
tachycardia fibrillation
For Age 20:
What is the target HR zone for tachycardias?
100-170 bpm (50-85%)
For Age 20:
What is the maximum HR (average)?
200 bpm
For Age 30:
What is the target HR zone for tachycardias?
95-162 bpm
For Age 30:
What is the maximum HR (average)?
190 bpm
For Age 40:
What is the target HR zone for tachycardias?
90-153 bpm
For Age 40:
What is the maximum HR (average)?
180 bpm
For Age 50:
What is the target HR zone for tachycardias?
85-145 bpm
For Age 50:
What is the maximum HR (average)?
170 bpm
What is PSVT?
Paroxysmal Supraventricular Tachycardia
Paroxysmal Supraventricular Tachycardia:
Rate?
Usually 140-250 ppm and “takes off” in a single beat
Paroxysmal Supraventricular Tachycardia:
Rhythm?
regular ventricular rate
Paroxysmal Supraventricular Tachycardia:
P waves?
often absent
Paroxysmal Supraventricular Tachycardia:
PR interval?
normal
Paroxysmal Supraventricular Tachycardia:
QRS ?
narrow
Atrial Flutter:
Atria Rate?
250-350 bpm
Atrial Flutter:
Ventricular Rate?
125-175 bpm
Atrial Flutter:
Rhythm?
usually regular
Atrial Flutter:
P waves ?
saw tooth pattern
Atrial Flutter:
PR interval?
variable
Atrial Flutter:
QRS ?
normal
Atrial Fibrillation:
Rate?
variable, but usually 350-450 bpm
Atrial Fibrillation:
Rhythm?
Irregularly irregular
Atrial Fibrillation:
P waves?
chaotic activity
Atrial Fibrillation:
PR interval?
none
Atrial Fibrillation:
QRS ?
normal
Ventricular Flutter:
Rate?
200-300 bpm
Ventricular Flutter:
Rhythm?
regular
Ventricular Flutter:
P waves?
NONE
Ventricular Flutter:
PR interval?
NONE
Ventricular Flutter:
QRS?
wide, bizarre, sine-wave appearance
__________ _________ = VERY BAD FOR THE PATIENT = DEATH
Ventricular Fibrillation
Ventricular Fibrillation:
Rate?
very hard to determine
Ventricular Fibrillation:
Rhythm?
chaotic
Ventricular Fibrillation:
P waves?
None
Ventricular Fibrillation:
PR interval?
None
Ventricular Fibrillation:
QRS?
cannot determine
______ __ _______ = also very bad for the patient
Torsade de Pointes
Torsade de Pointes can cause ?
QT Prolongation
Torsade de Pointes:
Rate?
200-250 bpm
Torsade de Pointes:
Rhythm?
Irregular
Torsade de Pointes:
P waves?
None
Torsade de Pointes:
PR Interval?
None
Torsade de Pointes:
QRS?
variable
What are some QT prolonging drugs?
- antipsychotics
- antidepressants
- antibiotics (fluoroquinolones)
- azole antifungals
- antiarrhythmics
What are some stimulant drugs?
- illicit drugs
- caffeine
- nicotine
- OTC decongestants
- ADHD treatments
______ = holiday heart syndrome
alcohol
1st degree heart block:
Rate?
variable (their example on page 3 is bradycardic)
1st degree heart block:
Rhythm?
normal
1st degree heart block:
P waves?
normal
1st degree heart block:
P:QRS ratio?
1:1
1st degree AV block:
PR interval?
prolonged > than 0.2 seconds (1 large square)
1st degree AV block:
QRS ?
normal
2nd degree AV block
Mobitz 1 (Wenchebach):
Rate?
variable (this one is ~65 bpm)
2nd degree AV block
Mobitz 1 (Wenchebach):
Rhythm?
regularly irregular
2nd degree AV block
Mobitz 1 (Wenchebach):
P waves?
normal
2nd degree AV block
Mobitz 1 (Wenchebach):
P:QRS ratio?
variable (5:4)
2nd degree AV block Mobitz 1 (Wenchebach): PR interval?
increases until beat is dropped
2nd degree AV block
Mobitz 1 (Wenchebach):
QRS ?
normal
2nd degree AV block
Mobitz 2:
Rate?
variable (this one is 75-83 bpm)
2nd degree AV block
Mobitz 2:
Rhythm?
regularly irregular
2nd degree AV block
Mobitz 2:
P waves?
normal
2nd degree AV block
Mobitz 2:
P:QRS ratio
P+1:QRS (ex. 3:2, 4:3, 5:4)
2nd degree AV block
Mobitz 2:
PR interval?
normal (not the difference between Mobitz 1)
2nd degree AV block
Mobitz 2:
QRS?
Normal
3rd degree AV block = _____
complete
3rd degree AV block:
Rate?
separate rates for atria and ventricles
ventricles = 38 bpm atria = 115 bpm
3rd degree AV block:
Rhythm?
normal
3rd degree AV block:
P waves?
normal (there’s usually lots of them)
3rd degree AV block:
P:QRS ratio ?
variable
3rd degree AV block:
PR interval?
variable (no pattern)
3rd degree AV block:
QRS ?
normal or wide
What drugs can cause heart block?
- beta blockers
- digoxin
- non-dihydropyridine calcium channel blockers (verapamil, diltiazem)
- some anti arrhythmic drugs (procainamide, amiodarone, quinidine, adenosine)
What are other (non-drug) things can cause heart block?
- heart disease and cardiac surgery
- high vagal tone (athletes)
- hyperkalemia (increased K+)