Download - Supravetricular Tachyarrhythmias Part 2
SupravetricularTachyarrhythmias
Part 2
Rey Vivo, MDAssistant Professor of Medicine
Texas Tech University Health Sciences Center
Objectives
• Describe the AVNRT
• Recognize and differentiate the Supraventricular Tachyarrhythmias
• PRACTICE, PRACTICE, PRACTICE!!!
Review of last week
• Two most important aspects of arrhythmias:
1. Their mechanism
2. Their site of origin
The two mechanisms that produce arrhythmias are:
1. Automaticity (problems of impulse formation)
2. Block or Reentry(problems of impulse
conduction)
The two mechanisms that produce arrhythmias are:
1. Automaticity (problems of impulse formation)
2. Block or Reentry(problems of impulse
conduction)
SVTs
• Accelerated Automaticity1. Sinus Tachycardia
2. Atrial Tachyarrhythmias
e.g. PAT with Block, MAT
3. Accelerated Junctional Rhythm
• Reentrant Atrial Tachyarrhythmias1. Atrial Flutter
2. Atrial Fibrillation
• Reentrant Junctional Tachyarrhythmias- The Atrioventricular Nodal and Bypass Tachycardias
RJT
• Reentrant Junctional Tachyarrhythmias
1. AVNRT – Atrioventricular Nodal Reentrant Tachycardia
2. Atrioventricular Bypass Tachycardia
AVNRT
• Rate: 140 – 220 beats/minute• Usually 1:1 atrial-ventricular association• Every QRS has a P (concealed, fused or retrograde)
AVNRT
AVNRT
SVT Differentials
SVT Rate Rhythm P wave Adenosine effect
Sinus tach 100 - (220-age) Regular Discrete anterograde
P waves
Gradual slowing, then reaccelerates
AAR 140 - 250 Regular “Not sinus”
antegrade P
Gradual slowing to reveal atrial activity
MAT > 100 Irregular > 3 different forms in 1 lead
NA
AJR 60 - 130 Regular Inverted, absent or after QRS
Gradual slowing, then reaccelerates
Flutter A: 220-430
V: <300
Regular or Reg. Irreg.
F waves Gradual slowing to reveal atrial activity
Fibrillation A: 350-650
V: slow to rapid
Irreg. Irreg. f waves Gradual slowing to reveal atrial activity
AVNRT 140-220
(A:V 1:1)
Regular Absent or discrete retrograde P waves
“Breaks” abruptly, converts to sinus
Narrow Complex Tachs
• Regular– “Normal” ante Ps..ST– Abnormal Ps
• Rate < 140……….AJR• Rate > 140
– Ante P…………AAR– No or Retro P...AVNRT
– F waves………….Flut
• Irregular– Polymorphic Ps…..MAT– f waves…………….Fib– (Reg. irreg, F……...Flut)
Let’s practice!
Bix rule
Whenever the P of an SVT is halfway between QRS complexes always suspect that an extra P is hiding within the QRS
EKG 1
EKG 2
EKG 3
EKG 4
EKG 5
EKG 6
EKG 7
EKG 8
EKG 9
EKG 10
The End