Management of Regular Wide QRS Complex Tachycardias
Management of Regular Wide QRS Complex Tachycardias
Presented at the Electrophysiology (EP) Session, Jordan Cardiac Society (JCS) Taskforce Congress, 2025
Speaker: Dr. Laith Saleh, Interventional Electrophysiologist
Reference: Based on AHA/ESC 2023–2025 Tachyarrhythmia Algorithms and Advanced Life Support Guidelines.
Keynotes :
1. Overview and Clinical Challenge
• Wide QRS Complex Tachycardia (WCT) represents one of the most critical emergency arrhythmias encountered in acute care.
• The key difficulty: distinguishing VT from SVT with aberrancy, as diagnostic algorithms are complex and sometimes unreliable.
• Rapid deterioration is possible, particularly with VT, so a structured algorithmic approach is essential for safe and timely management .
2. Step 1 – Determine Regularity and QRS Width
• First visual step: assess whether the rhythm is regular or irregular (ECG examples shown on slides 6–7).
• Then evaluate if the QRS complex is narrow (<120 ms) or wide (≥120 ms) — the latter mandates urgent evaluation for VT until proven otherwise .
3. “Word of Caution” – When to Prepare for Shock
• If the rhythm is irregular with variable QRS morphology, consider:
• Polymorphic VT, or
• Atrial fibrillation with WPW (pre-excitation).
• Immediate preparation for defibrillation and expert help is warranted in these cases .
4. Hemodynamic Assessment
• Management depends on hemodynamic stability, not ECG appearance alone.
• Unstable patients: hypotension, chest pain, altered consciousness, or shock.
• Stable patients: maintained blood pressure and perfusion despite tachycardia.
• Always ensure team-based evaluation and continuous monitoring .
5. Immediate Cardioversion for Unstable WCT
• For unstable but conscious patients:
• Perform synchronized cardioversion.
• Use sedation and analgesia if feasible.
• Select shock type based on ECG pattern (monomorphic vs polymorphic VT) .
6. Diagnostic Approach in Stable Patients
• Obtain 12-lead ECG and record rhythm strips.
• Attempt vagal maneuvers or adenosine if the tachycardia is regular and monomorphic — these can provide both diagnostic and therapeutic benefit.
• Always record the ECG during the maneuver to capture changes .
7. Vagal Maneuvers – Dual Role
• Diagnostic: may unmask underlying atrial activity (flutter, AT).
• Therapeutic: can terminate AV node–dependent SVTs (AVNRT, AVRT).
• Ineffective in most cases of VT, though may reveal AV dissociation (helpful diagnostically).
• Examples: Valsalva maneuver, carotid sinus massage (with caution in elderly or carotid disease) .
8. Adenosine Use – Indications and Caution
• Can terminate:
• AVNRT, AVRT, and some idiopathic VTs (notably RVOT VT).
• Helps differentiate SVT with aberrancy from VT if response is diagnostic.
• Must always be given with resuscitation equipment ready due to risk of transient asystole or worsening conduction in pre-excitation .
9. If Rhythm Persists – Treat as VT
• When etiology remains uncertain after initial interventions, always treat as VT.
• Continue monitoring, initiate antiarrhythmic infusion (amiodarone or procainamide), and avoid AV nodal blockers until diagnosis is certain .
10. Pharmacologic Cardioversion in VT
• Amiodarone:
• 150 mg IV over 10 min → then 1 mg/min for 6 h.
• Procainamide:
• 20–50 mg/min infusion → stop when rhythm converts or 15 mg/kg max reached.
• Both may cause hypotension; close hemodynamic and ECG monitoring is mandatory .
11. Special Considerations
• Idiopathic VT (structurally normal heart):
• May respond to β-blockers or calcium-channel blockers.
• Underlying cardiac disease:
• Correct ischemia, heart failure, electrolytes, and drug toxicity before further interventions .
12. Stepwise Management of SVT (Algorithm Summary)
1. Vagal maneuvers.
2. Adenosine (if regular and monomorphic).
3. IV beta-blocker or calcium-channel blocker.
4. Electrical cardioversion if refractory.
(Flowchart displayed on slides 24–25 mirrors AHA ACLS 2020 and ESC 2022 updates.) .
13. WCT in Patients with Pacemakers or ICDs
• Pacemaker patients:
• WCT may result from tracking atrial arrhythmia or pacemaker-mediated tachycardia.
• Magnet application sets device to asynchronous pacing (VOO/DOO), terminating PMT.
• ICD patients:
• Always assume VT until proven otherwise.
• If multiple shocks occur without resolution → suspect VT storm or lead malfunction.
• Magnet suspends shocks but does not stop pacing .
14. Recurrent or Persistent WCT
• Reassess triggers: ischemia, electrolytes, toxicity.
• Reattempt cardioversion or give amiodarone infusion for suppression.
• Seek EP consultation for resistant or recurrent arrhythmias .
15. Long-Term Management
• For VT:
• Evaluate for ICD implantation if no reversible cause.
• Ablation to reduce recurrent VT episodes.
• For SVT:
• Manage per guideline-based therapy (rate/rhythm control, ablation if recurrent).
• Idiopathic VT:
• Treated effectively with ablation or medical therapy, not ICD .
16. Take-Home Message
“In any regular wide complex tachycardia of uncertain origin — always assume VT until proven otherwise.
Simplicity, safety, and structured teamwork save lives.”
