ECG Lectures ECG Lectures Wide Complex Tachycardias Wide Complex Tachycardias

Selim Krim, MDSelim Krim, MDAssistant ProfessorAssistant Professor

Texas Tech University Health Sciences CenterTexas Tech University Health Sciences Center

ObjectivesObjectivesUnderstand the importance and clinical consequence of Understand the importance and clinical consequence of making the right diagnosis of wide complex tachycardiamaking the right diagnosis of wide complex tachycardia

Get familiar with the different etiologies of wide complex Get familiar with the different etiologies of wide complex tachycardiatachycardia

Step wise approach to diagnosing wide complex Step wise approach to diagnosing wide complex tachycardiatachycardia

Recognize SVT with aberrancy from ventricular Recognize SVT with aberrancy from ventricular TachycardiaTachycardia

Differential Diagnosis of Wide QRS Tachycardias

Ventricular TachycardiaVentricular Tachycardia

Supraventricular Tachycardia with BBB or WPWSupraventricular Tachycardia with BBB or WPW

Atrial fibrillation with aberration or with WPWAtrial fibrillation with aberration or with WPW

Clinical pearlsClinical pearls

One of the most common lethal errors made in One of the most common lethal errors made in arrhythmia diagnosis is to mistake VT for SVT and treat arrhythmia diagnosis is to mistake VT for SVT and treat with with verapamil, diltiazem, and adenosineverapamil, diltiazem, and adenosine, all of which , all of which can precipitate ventricular fibrillation in patients in VT, can precipitate ventricular fibrillation in patients in VT, even if initially stable.even if initially stable.

Therefore, all wide-complex tachycardias should be Therefore, all wide-complex tachycardias should be assumed to be VT until proven otherwise.assumed to be VT until proven otherwise.

Bedside Clues to V-TachBedside Clues to V-Tach

Advanced heart diseaseAdvanced heart disease (e.g., coronary heart (e.g., coronary heart disease) statistically favors ventricular tachycardia disease) statistically favors ventricular tachycardia

Cannon 'a' wavesCannon 'a' waves in the jugular venous pulse in the jugular venous pulse suggests ventricular tachycardia with suggests ventricular tachycardia with AV dissociationAV dissociation. . Under these circumstances atrial contractions may Under these circumstances atrial contractions may occur when the tricuspid valve is still closed which occur when the tricuspid valve is still closed which leads to the giant retrograde pulsations seen in the JV leads to the giant retrograde pulsations seen in the JV pulse. With AV dissociation these giant a-waves occur pulse. With AV dissociation these giant a-waves occur irregularly.irregularly.

If the patient is hemodynamically unstable, If the patient is hemodynamically unstable, think think ventricular tachycardiaventricular tachycardia and act accordingly! and act accordingly!

Ventricular TachycardiaVentricular Tachycardia

A run of three (3) or more consecutive PVCsA run of three (3) or more consecutive PVCs

Sustained (lasting >30 sec) vs. nonsustained Sustained (lasting >30 sec) vs. nonsustained

Monomorphic Monomorphic (uniform morphology) vs. (uniform morphology) vs. polymorphicpolymorphic vs. vs. Torsade-de-pointesTorsade-de-pointes    

Torsade-de-pointesTorsade-de-pointes:: a polymorphic ventricular a polymorphic ventricular tachycardia associated with the long-QT syndromes tachycardia associated with the long-QT syndromes characterized by phasic variations in the polarity of characterized by phasic variations in the polarity of the QRS complexes around the baseline.  the QRS complexes around the baseline.  

Monomorphic Ventricular Tachycardia

Torsades de Pointes

ECG Clues to Ventricular ECG Clues to Ventricular TachycardiaTachycardia

Regularity of the rhythmRegularity of the rhythm:: If the wide QRS tachycardia is If the wide QRS tachycardia is sustained and monomorphic, then the rhythm is usually regular sustained and monomorphic, then the rhythm is usually regular (i.e., RR intervals equal)(i.e., RR intervals equal)

A-V DissociationA-V Dissociation strongly suggests strongly suggests ventricular tachycardiaventricular tachycardia! ! Unfortunately AV dissociation only occurs in approximately 50% Unfortunately AV dissociation only occurs in approximately 50% of ventricular tachycardias . of ventricular tachycardias .

Fusion beats or capturesFusion beats or captures often occur when there is AV often occur when there is AV dissociation and this also strongly suggests a ventricular origin dissociation and this also strongly suggests a ventricular origin for the wide QRS tachycardia. for the wide QRS tachycardia.

ECG Clues for V TachECG Clues for V Tach

Bizarre frontal-plane QRS axis (i.e. from +150 degrees to -90 Bizarre frontal-plane QRS axis (i.e. from +150 degrees to -90 degrees or degrees or NW quadrantNW quadrant) suggests ) suggests ventricular tachycardiaventricular tachycardia

QRS morphology similar to previously seen PVCs suggests QRS morphology similar to previously seen PVCs suggests ventricular tachycardiaventricular tachycardia

If all the QRS complexes from V1 to V6 are in the If all the QRS complexes from V1 to V6 are in the same directionsame direction (positive or negative), (positive or negative), ventricular tachycardiaventricular tachycardia is likely   is likely  

Especially wide QRS complexes Especially wide QRS complexes (>0.16s)(>0.16s) suggests suggests ventricular ventricular tachycardiatachycardia

Ventricular Tachycardia

Ventricular Tachycardia

V-Tach vs. SVT with AberrancyV-Tach vs. SVT with Aberrancy

Features favoring VT:Features favoring VT:

RBBB PatternRBBB Pattern

MonophasicMonophasic R or R or biphasicbiphasic qR, qR, QR, or RS in V1 QR, or RS in V1

S > R or QS in V6 S > R or QS in V6     LBBB patternLBBB pattern

Broad R wave or wide R-S Broad R wave or wide R-S length (> 30msec) in V1 or V2length (> 30msec) in V1 or V2

Notched downstroke of S-Notched downstroke of S-

wave in V1 or V2wave in V1 or V2 qR or QS pattern in V6   qR or QS pattern in V6  

Features favoring SVT:Features favoring SVT:

RBBB patternRBBB pattern

TriphasicTriphasic rSR' in V1 rSR' in V1

Triphasic rSR' in V6Triphasic rSR' in V6 R > S in V6R > S in V6

LBBB patternLBBB pattern

No R in V1 No R in V1

No slurring of S-wave No slurring of S-wave downstroke downstroke

Monophasic R in V6 Monophasic R in V6

Presence of septal Q in I & V6 Presence of septal Q in I & V6

Aberrancy vs. EctopyAberrancy vs. Ectopy

If the QRS in V1 is mostly positiveIf the QRS in V1 is mostly positive the the following possibilities exist:  following possibilities exist:  rsRrsR' or ' or rSR'rSR' QRS QRS morphologies suggests morphologies suggests RBBB aberrancyRBBB aberrancy >90% of the time! >90% of the time!

Aberrancy vs. EctopyAberrancy vs. Ectopy

Monophasic R waves or R waves with a notch Monophasic R waves or R waves with a notch or slur on the or slur on the downstrokedownstroke of the R waves of the R waves suggests suggests ventricular ectopyventricular ectopy > 90% of the time > 90% of the time (see below)!(see below)!

R waves with a notch or slur on the R waves with a notch or slur on the downstrokedownstroke of the R waves of the R waves

Monophasic R wave with a notch or slur on Monophasic R wave with a notch or slur on the the upstrokeupstroke of R wave: 50-50 possibility or of R wave: 50-50 possibility or either!either!

Four-step Algorithm to Wide Four-step Algorithm to Wide Complex TachycardiaComplex Tachycardia

Step 1:Step 1: Absence of RS complex in Absence of RS complex in allall leads V1-V6? leads V1-V6?Yes: Dx is ventricular tachycardia! Yes: Dx is ventricular tachycardia!

Step 2: No: Is interval from beginning of R wave to nadir of S wave Step 2: No: Is interval from beginning of R wave to nadir of S wave >0.1s in any RS lead? >0.1s in any RS lead? Yes: Dx is ventricular tachycardia! Yes: Dx is ventricular tachycardia!

Step 3: No: Are AV dissociation, fusions, or captures seen?Step 3: No: Are AV dissociation, fusions, or captures seen?Yes: Dx is ventricular tachycardia! Yes: Dx is ventricular tachycardia!

Step 4: No: Are there Step 4: No: Are there morphology criteriamorphology criteria for VT present both in leads for VT present both in leads V1 and V6?V1 and V6?Yes: Dx is ventricular tachycardia! Yes: Dx is ventricular tachycardia!

NO: Diagnosis is supraventricular tachycardia with NO: Diagnosis is supraventricular tachycardia with aberration!aberration!

Atrial Fibrillation With WPW

Atrial FibrillationAtrial Fibrillation

V-tach or SVT with BBB?V-tach or SVT with BBB?

Diagnosis?Diagnosis?

Let’s practice!Let’s practice!

ECG 1

ECG 2

ECG 3

ECG 4

ECG 5

ECG 6

ECG 7

ECG 8

ECG 9

Brugada Criteria

Questions ?Questions ?

Thank youThank you