Diagnosis and Management of Wide QRS Complex Tachycardia

Initial Assessment and Diagnosis

The American College of Cardiology recommends that if a patient is hemodynamically unstable, proceed immediately to synchronized DC cardioversion regardless of the underlying mechanism 2, 1, 3
The presence of a two-peaked QRS pattern, also known as notching, is most commonly associated with right bundle branch block (RBBB) or ventricular tachycardia (VT), with the immediate priority being determining hemodynamic stability followed by distinguishing between these entities 1
Stable vital signs do not help distinguish between supraventricular tachycardia (SVT) and VT 1
A tachyarrhythmia is typically characterized by a heart rate greater than 100 bpm, requiring urgent diagnosis 3
The American College of Cardiology suggests that a baseline conduction abnormality, such as a sinus rhythm with bundle branch block, should be considered in the differential diagnosis 3

The American College of Cardiology states that complete right bundle branch block (RBBB) is characterized by a QRS duration of 120 ms or greater, an rsr', rsR', rSR', or rarely qR pattern in leads V1 or V2, and an S wave of greater duration than the R wave or greater than 40 ms in leads I and V6 4, 3
Ventricular tachycardia (VT) should be considered when the two-peaked pattern occurs during tachycardia, especially in patients with a history of previous myocardial infarction, which strongly suggests VT 2, 1
The American College of Cardiology recommends that an RS interval greater than 100 ms from the initial R to the nadir of the S wave in any precordial lead is highly specific for VT 2, 1

The American College of Cardiology suggests that when the diagnosis is uncertain, it is safest to treat as VT 1, 3
For hemodynamically stable patients, the American College of Cardiology recommends IV procainamide and/or sotalol for stable wide QRS-complex tachycardia of ventricular origin, and amiodarone for patients with impaired left ventricular function or heart failure 1
The American College of Cardiology advises against administering verapamil or diltiazem for wide-complex tachycardia of uncertain etiology, as this can cause severe hypotension or accelerated ventricular rate in VT or pre-excited atrial fibrillation 3

After successful termination of wide QRS-complex tachycardia of unknown etiology, the American College of Cardiology recommends referring patients to an arrhythmia specialist 1
For confirmed Wolff-Parkinson-White (WPW) syndrome, long-term management options include catheter ablation or drug therapy, as recommended by the American College of Cardiology 1