Director’s question: What are the 7 ways to identify ventricular tachycardia or supraventricular tachycardia?

The QRS wave is the depolarization wave of the ventricle, and its width is both the depolarization Time of the ventricle and the time of excitation conduction in the ventricle. The normal adult QRS wave group time limit is 0.06-0.10 s, the longest is not greater than 0.12 s.

Wide QRS tachycardia is defined as tachycardia in which the ventricular rate is greater than 100 beats/min and the QRS wave time frame is greater than 0.12 s. About 80% of these tachycardias are ventricular. About 80% of these are ventricular tachycardia (VT); about 20% are supraventricular tachycardia (SVT) with intraventricular variability and some rare arrhythmias.

The rapid onset and progression of wide QRS wave tachycardia is often a problem for physicians, and a timely and correct diagnosis can provide more favorable evidence for treatment. Therefore, this article provides an inventory of methods to identify wide QRS tachycardia.

Wellens method

There are 4 diagnostic criteria, which are mainly used for the diagnosis of left ventricular tachycardia.

① QRS wave duration > 140 ms.

② Left deviation of the electrical axis.

③ V1 lead: QRS wave is RS or RSr (rabbit ear sign) type, V6 lead: QRS wave is rS or QS type.

④ Atrioventricular separation and ventricular seizure.

Image source: Ding Xiang Yuan Forum

Kindwall method

There are 5 diagnostic criteria, mainly used for the diagnosis of right ventricular tachycardia.

① r-wave time limit in V1 and V2 leads > 30 ms.
(2) The presence of cut marks in the descending S-wave in V1 and V2 leads.
③ rS interval in V1 and V2 leads > 60 ms.
④ q-wave or Q-wave in V6 leads.
⑤ QRS wave duration ≥ 160 ms.

Griffith method

Exclusionary methods to diagnose ventricular tachycardia.

(1) left bundle branch block type of supraventricular tachycardia: rS or QS type in V1 and V2, QRS wave group start to S wave nadir interval < 70 ms, R type without Q wave in V6.

(ii) Supraventricular tachycardia with right bundle branch block: V1 with rSR, R’ > r, V6 with RS (including Q-wave < 40 ms and 0.2 mV), R > S.

(iii) ECG patterns in tachycardia consistent with Griffith’s definition of bundle branch block patterns are diagnostic of supraventricular tachycardia, and vice versa.

④ The diagnosis of supraventricular tachycardia could not be confirmed, and ventricular tachycardia was taken as the diagnosis.

Brugada method

4-step process method.

① No RS-type QRS waves in all anterior chest leads.
② RS interval > 100 ms.
③ Atrioventricular separation.
④ Graphical characteristics of ventricular tachycardia QRS waves.

If all of the above are negative, the diagnosis is SVT.

To further differentiate preexcited tachycardia from ventricular tachycardia, an additional 3-step process was added to the above 4-step process.

(i) predominantly negative waves in V4-6 leads.
(ii) The presence of qR waves in leads V4-6.
(3) Atrial separation.

Image credit: Courtesy of the authors

Vereckei single AVR conduction method

4-step process method.

① Observe whether the AVR lead initially shows a large R wave and the QRS wave in the AVR lead is R or RS shaped.
② QRS wave start r or q wave width > 40 ms.
(3) Stuttering of negative QRS wave onset in AVR leads.
④ Ventricular terminal excitation velocity (Vt, voltage change in the last 40 ms of QRS) ≥ ventricular initial excitation velocity (Vi, voltage change in the first 40 ms of QRS), and the Vi/Vt value of QRS wave < 1 is ventricular tachycardia.

If all of the above are negative, the diagnosis is SVT.

Image source: Courtesy of the authors

Ventricular tachycardia integration method

① V1 lead QRS wave with significant R wave.
② r-wave time limit of V1 or V2 lead QRS wave > 40 ms.
(③) The S wave of V1 lead QRS wave has a tangent.
④ V1 to V6 QRS waves without RS pattern.
(⑤) AVR lead QRS wave is initially R wave.
(6) R-wave peak time in lead II ≥ 50 ms.
(7) Atrial separation.

Among the above 7 criteria, 2 points will be awarded for positive atrial separation and 1 point will be awarded for the rest.

The diagnostic zone of ventricular tachycardia: ventricular tachycardia can be diagnosed when the score of ventricular tachycardia is ≥ 2, and the specificity of ventricular tachycardia diagnosis is 89% and the accuracy is 81.4%.

The gray zone of ventricular tachycardia diagnosis: when the ventricular tachycardia integral method accumulates 1 point, the percentage of ventricular tachycardia (54.5%) and supraventricular tachycardia (45.5%) are similar at this time.

Diagnostic zone of supraventricular tachycardia: those with a score of 0 after evaluation by the ventricular tachycardia integration method should be diagnosed with supraventricular tachycardia.

Limb lead method

① If the AVR leads show monomorphic R waves, then ventricular tachycardia is diagnosed and supraventricular tachycardia is excluded.

(ii) If the QRS waves in leads I, II, and III are predominantly negative and can be QS, Qr, rS, Qrs, qrS, rSr’, or even quadruple or more phase waves, then the diagnosis is ventricular tachycardia and supraventricular tachycardia is excluded.

(iii) If neither step 1 nor step 2 is satisfied, the same diagnosis of ventricular tachycardia is made if the limb leads have opposing QRS waves. This step contains the following two levels.

  • (i) All three inferior wall leads (II, III, AVF) have a monomorphic QS/R shape with the same polarity (i.e., all are positive or negative, including staccato R or QS shapes).
  • Two or three of the remaining three limb leads (I, AVL, AVR) show a monomorphic R/QS shape, but the polarity of the QRS wave is opposite to that of the inferior wall lead.

If the AVR leads show a monomorphic R wave, the diagnosis is ventricular tachycardia and supraventricular tachycardia is excluded.


The differential diagnosis of wide QRS wave tachycardia has always been a clinical hotspot and a difficult problem, and as research continues to progress, there are more and more differential diagnosis methods for wide QRS wave tachycardia, but no matter which differential method is chosen, early diagnosis and treatment is the key.