1. WIDE QRS TACHYCARDIA - BEDSIDE DIAGNOSIS
Dr.K.Chandrasekaran.MD.DM
Interventional cardiologist and
Cardiac Electrophysiologist

2. CLASSIFICATION OF TACHYCARDIAS WITH A BROAD QRS COMPLEX
SVT WITH BBB
ATRIAL TACHYCARDIA
ATRIAL FLUTTER
ATRIAL FIBRILLATION
AV NODAL RE-ENTRANT TACHYCARDIA
CMT WITH AV CONDUCTION OVER AV NODE AND VA CONDUCTION OVER ACC PATHWAY

3. SVT WITH AV CONDUCTION OVER ACC PATHWAY
ATRIAL TACHYCARDIA
ATRIAL FLUTTER
ATRIAL FIBRILLATION
AV NODAL RE-ENTRANT TACHYCARDIA

4. Antidromic circus movement tachycardia using an accessory pathway in the antegrade direction and AV Node or another acc pathway in the retrograde direction
AV Reentry tachycardia using a Mahaim fibre in the antegrade direction and AV Node or another acc pathway in the retrograde direction

5. VENTRICULAR TACHYCARDIA

6. VT
Regular
SVT with BBB
SVT with AV conduction
Over accessory pathway

7. AF Irregular PMVT with Normal QT PMVT with long QT BBB
Accessory Pathway
Irregular
PMVT with Normal QT
PMVT with long QT

11. THE ECG DIAGNOSIS IMPORTANCE OF AV DISSOCIATION AVD HALLMARK OF VT .
VA CONDUCTION DURING SLOW VT.
P WAVES CAN BE DIFFICULT TO RECOGNISE
NON ECG SIGNS
FUSION CAPTURE BEATS
AVD IN AVJT WITH BBB AFTER CARDIAC SURGERY OR DURING DIG INTOXICATION

15. A 47 year old man with a long history of palpitations and blackouts.
Wolf-Parkinson-White syndrome with atrial fibrillation
irregularly irregular, wide complex tachycardia
impulses from the atria are conducted to the ventricles via either
both the AV node and accessory pathway producing a broad fusion complex
or just the AV node producing a narrow complex (without a delta wave)
or just the accessory pathway producing a very broad 'pure' delta wave
people who develop this rhythm and have very short R - R intervals are at higher risk of VF 15 15

16. A 23 year old male with palpitations
Wolf-Parkinson-White syndrome with atrial fibrillation
irregularly irregular, wide complex tachycardia
impulses from the atria are conducted to the ventricles via either
both the AV node and accessory pathway producing a broad fusion complex
or just the AV node producing a narrow complex (without a delta wave)
or just the accessory pathway producing a very broad 'pure' delta wave
people who develop this rhythm and have very short R - R intervals are at higher risk of VF 16 16

17. WIDTH OF QRS COMPLEX SITE OF ORIGIN OF VT
ORIGIN IN THE LATERALFREE WALL  VERY WIDE QRS ( SEQUENTIAL ACTIVATION OF THE VENTRICLES)
ORIGIN IN OR CLOSE TO THE IVS  NARROWER QRS ( SIMULTANEOUS ACTIVATION OF THE VENTRICLES )
SCAR TISSUE , VENTRICULAR HYPERTROPHY AND MUSCULAR DISARRAY
QRS WIDTH > 0.14 SECS IN RBBB TACHYCARDIAS AND > 0.16 SECS IN LBBB TACHYCARDIAS  ARGUES FOR A VT.

18. WIDTH OF QRS COMPLEX
SVT WITH QRS WIDTH > 0.14 SECS (RBBB) OR > 0.16 SECS (LBBB) IN THREE CONDITIONS:
IN THE PRESENCE OF BBB IN THE ELDERLY WITH FIBROSIS IN THE BB SYSTEM AND VENTRICULAR MYOCARDIUM
DURING SVT WITH AV CONDUCTION OVER AN ACCESSORY AV PATHWAY
WHEN CLASS 1 C DRUGS ARE PRESENT DURING SVT

21. QRS AXIS IN THE FRONTAL PLANE
SUPERIOR AXIS  VT ORIGIN IN THE APICAL PART OF THE VENTRICLE.
RBBB SHAPED QRS + SUPERIOR AXIS  VT
INFERIOR AXIS  VT ORIGIN IN THE BASAL VENTRICLE.
LBBB SHAPED QRS + INFERIOR AXIS VT

23. CONFIGURATIONAL CHARACTERISTICS OF THE QRS COMPLEX
RBBB SHAPED TACHYCARDIA
qR OR R IN VI  VT
rSR PATTERN IN VI  SVT
R/S RATIO < 1 IN V6  VT
R/S RATIO < 1 IN V6 TYPICALLY FOUND WITH LEFT AXIS
DEVIATION.
WITH INFERIOR AXIS V6 OFTEN SHOWS R/S RATIO > 1
qRS in V6 with R/S in V6 > SVT

24. CONFIGURATIONAL CHARACTERISTICS OF THE QRS COMPLEX
LBBB SHAPED VT
V1,V2 SHOW INITIAL POSITIVE QRS ( r wave)> 30 mSecs,
SLURRING / NOTCHING OF THE DOWN STROKE OF
THE S-WAVE,
AN INTERVAL BETWEEN THE BEGENNING OF QRS
AND THE NADIR OF THE S-WAVE OF 70 msecs .
qR PATTERN IN V6  VT IS MORE LIKELY

25. CONFIGURATIONAL CHARACTERISTICS OF THE QRS COMPLEX
SVT WITH LBBB
V1 SHOWS NO OR MINIMAL INITIAL POSITIVITY,
A VERY RAPID DOWNSTROKE OF THE SWAVE
A SHORT INTERVAL BETWEEN THE BEGENNING
OF THE QRS AND THE NADIR OF THE SWAVE

28. INTERVAL ONSET QRS TO NADIR OF SWAVE IN PRECORDIAL LEADS
RS INTERVAL > 100 msecs IN 1 OR MORE PRECORDIAL LEADS  VT
DIFFERENTIAL DIAGNOSIS
SVT WITH AV CONDUCTION OVER AN ACC
PATHWAY,
SVT DURING ADMINISTRATION OF DRUGS
LIKE FLECAINIDE.
IN SVT WITH PRE-EXISTENT BBB.

29. CONCORDANT PATTERN NEGATIVE CONCORDANCY VT ARISING IN THE APICAL AREA
POSITIVE CONCORDANCY  VT ARISING IN THE LEFT POSTERIOR WALL OR TACHYCARDIAS USING A LEFT POSTERIOR ACC PATHWAY FOR AV CONDUCTION

31. TACHYCARDIA QRS MORE NARROW THAN SINUS QRS
NARROW QRS DURING TACHYCARDIA THAN DURING SINUS RHYTHM 
VT ORIGIN CLOSE TO IVS

33. PRESENCE OF QR COMPLEXES
QR DURING WIDE QRS TACHYCARDIA INDICATES A SCAR IN THE MYOCARDIUM
QR COMPLEX DURING VT IN 40% OF VTs AFTER MI

35. RVOT VT IDIOPATHIC VT ARISING FROM RVOT 3 PATTERNS.
QRS AXIS + 70 AND LEAD 1 SHOWS A POSITIVE QRS
 ORIGIN OF VT IN THE LATERAL PART OF
RVOT
INFERIOR QRS AXIS, QRS NEGATIVE IN LEAD 1 
VT ORIGIN ON THE SEPTAL SIDE IN THE RVOT
INFERIOR QRS AXIS, NEGATIVE QRS IN LEAD 1 &
V1,V2 SHOWING INITIAL POSITIVITY OF THE QRS 
EPICARDIAL ORIGIN OF VT BETWEEN THE ROOT
OF THE AORTA AND THE POSTERIOR PART
OF THE RVOT .

37. IDIOPATHIC LEFT VT
LEFT AXIS DEVIATION  ORIGIN OF THE VT IS IN OR CLOSE TO THE POSTERIOR FASCICLE OF THE LBB
FURTHER LEFTWARD QRS AXIS (NORTH-WEST AXIS) ORIGIN OF VT MORE ANTERIORLY CLOSE TO THE IVS
INFERIOR QRS AXIS VT ORIGIN IN THE ANTERIOR FASCICLE OF THE LBB

39. ARVD 3 PREDILECTION SITES IN THE RV THE INFLOW THE OUTFLOW THE APEX
LEFT AXIS DEVIATION IN A YOUNG PERSON WITH LBBB SHAPED VT  ARVD

40. BBRT
WHEN THE BROAD QRS IS IDENTICAL DURING TACHYCARDIA AND SINUS RHYTHM  BBRT OR SVT WITH PRE-EXISTENT BBB
BBRT OCCUR IN PATIENTS WITH ASMI, DCMY, MYOTONIC DYSTROPHY, AFTER AORTIC VALVE SURGERY

43. VALUE OF ECG DURING SINUS RHYTHM
ECG DURING SINUS RHYTHM MAY SHOW PRE-EXISTENT BBB, VENTRICULAR PRE-EXCITATION OR AN OLD MI
PRESENCE OF AV CONDUCTION DISTURBANCES DURING SINUS RHYTHM  VERY UNLIKELY THAT A BROAD QRS TACHYCARDIA IN THAT PATIENT HAS A SUPRAVENTRICULAR ORIGIN

44. Emergency Approach – Wide QRS Tachycardia
Do not panic when confronted with WCT
Obtain a 12 Lead ECG

45. If Hemodynamically Unstable
Carrdiovert
Obtain a history
Examine the pre and post cardioversion ECG’S to determine the etiology of the arrhythmia

46. If Hemodynamically Stable
Examine the patient for clinical signs of AVD
Systematically evaluate the 12 Lead ECG
Obtain a history

47. If Ventricular Tachycardia
Give Procainamide 10mg/kg IV bolus over 5 minutes
If Ischemia related – Give Lidocaine
If unsuccessful, Cardiovert
Examine the ECG during VT and during sinus rhythm to determine the etiology of the arrhythmia

48. If SVT with aberration Vagal stimulation. If unsuccessful,
Adenosine 6 mg rapid IV bolus. If unsuccessful,
Give 12 mg rapid IV bolus. May be repeated once. If unavailable ,
Verapamil 10 mg IV over 3 minutes, reduce to 5 mg if the patient is on beta blocker or hypotensive. If unsuccessful,
Procainamide 10 mg/kg IV over 5 minutes. If unsuccessful,
Cardiovert

49. Examine SVT and post- conversion ECG’s to determine the mechanism
If in doubt, do not give verapamil, give IV Procainamide
If irregular, Do not give AV nodal blocking drugs like BB, CCB, Adenosine or Digitalis
Give Procainamide IV or Amiodarone or Propafenone

50. Polymorphic VT with Normal QT
Most frequently caused by Acute ischemia or MI
Poorly tolerated
Tends to degenerate into VF quickly
Rarely it is caused by ARVD, IPMVT (short coupled variant of TDP) or familial catecholaminergic PMVT

51. Polymorphic VT with long QT
Initiation of tachycardia is pause dependent with late coupled PVC (long short initiating sequence)
Usually non sustained
Syncope
ECG abnormalities – Long QTc, abnormally shaped T waves

52. Treatment
Sustained PMVT – unstable rhythm with hemodynamic compromise and frequent degeneration into VF
Electrical cardioversion is the first line of therapy to decrease the recurrence and as treatment for NSPMVT
BB recommended for PMVT with normal QT
Magnesium for PMVT with long QT

53. CONCLUSION
WCT– VT MOST COMMON
HISTORY IS IMPORTANT
POST MI - WCT IS ALWAYS VT UNLESS PROVED OTHERWISE
PMVT WITH NORMAL QT - ACUTE ISCHAEMIA

54. THANK YOU