Rhythm diagnosis in regular wide complex tachycardia: Difference between revisions

No edit summary
No edit summary
Line 1: Line 1:
<big>''Assume [[ventricular tachycardia]] until proven otherwise''</big>
==Background==
==Background==
*Ventricular Tachycardia vs. Supraventricular Tachycardia
*Ventricular tachycardia vs. supraventricular tachycardia
**<big>'''Assume V-tach until proven otherwise'''</big>


== V-Tach vs. [[SVT]]  ==
== V-Tach vs. [[SVT]]  ==
{| class="wikitable"
{| class="wikitable"
|-
|-
Line 92: Line 92:
=== Brugada Algorithm  ===
=== Brugada Algorithm  ===


#Absence of an RS complex in all precordial leads?  
*Absence of an RS complex in all precordial leads?  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#RS interval &gt;100ms in any precordial lead? (onset of R wave to deepest part of S wave)  
*RS interval &gt;100ms in any precordial lead? (onset of R wave to deepest part of S wave)  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#AV dissociation?  
*AV dissociation?  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Morphology criteria for v-tach present in both V1-2 and V6?  
*Morphology criteria for v-tach present in both V1-2 and V6?  
##If yes then VT  
**If yes then VT  
##If no then possibly SVT w/ aberrant conduction
**If no then possibly SVT w/ aberrant conduction


=== aVR Algorithm  ===
=== aVR Algorithm  ===
Line 109: Line 109:
*In lead aVR:
*In lead aVR:


#Presence of an initial R wave?  
*Presence of an initial R wave?  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Presence of an initial r or q wave &gt;40ms  
*Presence of an initial r or q wave &gt;40ms  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Presence of a notch on descending limb of a negative onset, predominantly negative QRS?  
*Presence of a notch on descending limb of a negative onset, predominantly negative QRS?  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Ventricular activation-velocity ratio (Vi/Vt) ≤1?  
*Ventricular activation-velocity ratio (Vi/Vt) ≤1?  
##If yes then VT  
**If yes then VT  
##If no then SVT
**If no then SVT


=== Niemann Algorithm<ref>James Niemann MD FACEP is EM Faculty at Harbor-UCLA Medical Center and prominent resuscitation researcher</ref>  ===
=== Niemann Algorithm<ref>James Niemann MD FACEP is EM Faculty at Harbor-UCLA Medical Center and prominent resuscitation researcher</ref>  ===
Line 127: Line 127:
Acronym: <big>CARMA</big> -> '''Concordance -> aVR ->Regular -> Morphology ->AV dissociation'''
Acronym: <big>CARMA</big> -> '''Concordance -> aVR ->Regular -> Morphology ->AV dissociation'''


#Presence of an initial '''R wave in aVR'''? <ref>Vereckei A et al. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachy- cardia. Heart Rhythm 2008; 5:89-98</ref><ref>Szelenyi Z, et al. Acad Emerg Med 2013;20:1121- 1130</ref>
*Presence of an initial '''R wave in aVR'''? <ref>Vereckei A et al. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachy- cardia. Heart Rhythm 2008; 5:89-98</ref><ref>Szelenyi Z, et al. Acad Emerg Med 2013;20:1121- 1130</ref>
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Is there '''concordance''' (monophasic with same polarity) in all of the precordial leads? <ref>Brugada P et al. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation 1991;83:1649-1659</ref>
*Is there '''concordance''' (monophasic with same polarity) in all of the precordial leads? <ref>Brugada P et al. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation 1991;83:1649-1659</ref>
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Is there evidence of '''AV dissociation'''?  
*Is there evidence of '''AV dissociation'''?  
##If yes then VT  
**If yes then VT  
##If no then continue
**If no then continue
#Is the QRS '''morphology''' in V1 and V6 consistent with either '''LBBB''' or '''RBBB'''? <ref>Brugada, Circulation; Griffith MJ et al. Lancet 1994;343:386-388</ref><ref>Wellens HJJ et al. Am J Med 1978; 64:27-33</ref>
*Is the QRS '''morphology''' in V1 and V6 consistent with either '''LBBB''' or '''RBBB'''? <ref>Brugada, Circulation; Griffith MJ et al. Lancet 1994;343:386-388</ref><ref>Wellens HJJ et al. Am J Med 1978; 64:27-33</ref>
##If no then VT  
**If no then VT  
##If yes then SVT with aberrancy
**If yes then SVT with aberrancy


=== R-Wave Peak Time Method===
=== R-Wave Peak Time Method===
#In lead II, if the TIME in (ms) it takes the R wave to go from the isoelectric line to its peak voltage is greater than 50ms, it is VT
*In lead II, if the TIME in (ms) it takes the R wave to go from the isoelectric line to its peak voltage is greater than 50ms, it is VT
#Positive Likelihood ratio of 34.8
*Positive Likelihood ratio of 34.8


=== Lesser Known Criteria===
=== Lesser Known Criteria===
#Josephson's sign --- notching or slurring near the nadir of the S-wave is characteristic of V. Tach[[File:Josephson’s sign.jpg|thumbnail|Josephson's Sign Vtach]]
*Josephson's sign --- notching or slurring near the nadir of the S-wave is characteristic of V. Tach[[File:Josephson’s sign.jpg|thumbnail|Josephson's Sign Vtach]]
#Rsr' sign --- A taller left R wave in v1-v2 is very specific for VT, as opposed in a RBBB where the second/right R-wave (R') is taller
*Rsr' sign --- A taller left R wave in v1-v2 is very specific for VT, as opposed in a RBBB where the second/right R-wave (R') is taller
#"Northwest" axis deviation -- Negative QRS complex in I, AVF and Positive QRS in AVR
*"Northwest" axis deviation -- Negative QRS complex in I, AVF and Positive QRS in AVR


== See Also  ==
== See Also  ==

Revision as of 04:10, 9 April 2015

Assume ventricular tachycardia until proven otherwise

Background

  • Ventricular tachycardia vs. supraventricular tachycardia

V-Tach vs. SVT

Factor
 V Tach SVT w/ Aberrancy
Age >50 <35
History MI, CHF, CABG, MVR MVR, WPW
Cannon A Waves Present Absent
Arterial Pulse Variation No variation
First heart sound Variable Not variable
Fusion Beats Present Absent
AV dissociation Present Absent
QRS >0.14sec <0.14sec
Axis Extreme LAD (< -30) Normal or slightly abnl
Vagal Maneuvers No response Slows or terminates

QRS morphology

(RBBB-like pattern)

V1 - R or qR

V6 - rS

V1 - rsR'

V6 - R(slurredS)

QRS morphology

(LBBB-like pattern)

V1 or V2 - Broad R wave (>40msec)

V6 - Any Q or QS

V1 - rS or QS

V6 - qRs

Algorithms

  • Only for regular rhythms
  • Only for treatment decision if pt is stable
  • Assume V-tach until proven otherwise

Brugada Algorithm

  • Absence of an RS complex in all precordial leads?
    • If yes then VT
    • If no then continue
  • RS interval >100ms in any precordial lead? (onset of R wave to deepest part of S wave)
    • If yes then VT
    • If no then continue
  • AV dissociation?
    • If yes then VT
    • If no then continue
  • Morphology criteria for v-tach present in both V1-2 and V6?
    • If yes then VT
    • If no then possibly SVT w/ aberrant conduction

aVR Algorithm

  • In lead aVR:
  • Presence of an initial R wave?
    • If yes then VT
    • If no then continue
  • Presence of an initial r or q wave >40ms
    • If yes then VT
    • If no then continue
  • Presence of a notch on descending limb of a negative onset, predominantly negative QRS?
    • If yes then VT
    • If no then continue
  • Ventricular activation-velocity ratio (Vi/Vt) ≤1?
    • If yes then VT
    • If no then SVT

Niemann Algorithm[1]

  • Combination of the most specific aspects of the above two algorithms

Acronym: CARMA -> Concordance -> aVR ->Regular -> Morphology ->AV dissociation

  • Presence of an initial R wave in aVR? [2][3]
    • If yes then VT
    • If no then continue
  • Is there concordance (monophasic with same polarity) in all of the precordial leads? [4]
    • If yes then VT
    • If no then continue
  • Is there evidence of AV dissociation?
    • If yes then VT
    • If no then continue
  • Is the QRS morphology in V1 and V6 consistent with either LBBB or RBBB? [5][6]
    • If no then VT
    • If yes then SVT with aberrancy

R-Wave Peak Time Method

  • In lead II, if the TIME in (ms) it takes the R wave to go from the isoelectric line to its peak voltage is greater than 50ms, it is VT
  • Positive Likelihood ratio of 34.8

Lesser Known Criteria

  • Josephson's sign --- notching or slurring near the nadir of the S-wave is characteristic of V. Tach
    Josephson's Sign Vtach
  • Rsr' sign --- A taller left R wave in v1-v2 is very specific for VT, as opposed in a RBBB where the second/right R-wave (R') is taller
  • "Northwest" axis deviation -- Negative QRS complex in I, AVF and Positive QRS in AVR

See Also

Source

  • James Niemann MD. Harbor-UCLA Grand Rounds 2013
  • Pava et al. R-wave peak time at DII: a new criterion for differentiating between wide complex QRS tachycardias. Heart Rhythm. 2010 Jul;7(7):922-6
  1. ↑ James Niemann MD FACEP is EM Faculty at Harbor-UCLA Medical Center and prominent resuscitation researcher
  2. ↑ Vereckei A et al. New algorithm using only lead aVR for differential diagnosis of wide QRS complex tachy- cardia. Heart Rhythm 2008; 5:89-98
  3. ↑ Szelenyi Z, et al. Acad Emerg Med 2013;20:1121- 1130
  4. ↑ Brugada P et al. A new approach to the differential diagnosis of a regular tachycardia with a wide QRS complex. Circulation 1991;83:1649-1659
  5. ↑ Brugada, Circulation; Griffith MJ et al. Lancet 1994;343:386-388
  6. ↑ Wellens HJJ et al. Am J Med 1978; 64:27-33
Retrieved from "https://www.wikem.org/w/index.php?title=Rhythm_diagnosis_in_regular_wide_complex_tachycardia&oldid=35803"