What ECG rhythm corresponds to a heart rate of 87 beats per minute with a wide QRS complex and preserved T‑waves?

Wide QRS Complex Tachycardia at Rate 87 BPM

This is most likely an accelerated idioventricular rhythm (AIVR) or a supraventricular rhythm with bundle branch block, NOT ventricular tachycardia. The rate of 87 bpm falls below the typical threshold for tachycardia (>100 bpm by most definitions), making this a wide-complex rhythm at a relatively slow rate with preserved T-waves.

Key Diagnostic Considerations

Rate Analysis

• Wide-complex tachycardia is defined as rate >100 bpm with QRS >120 ms 1, 2
• At 87 bpm, this rhythm is technically not tachycardia but rather an accelerated rhythm
• This rate makes ventricular tachycardia unlikely, as VT typically presents at faster rates

Differential Diagnosis for Wide QRS at 87 BPM

Most likely possibilities:

1. Accelerated idioventricular rhythm (AIVR)

   • Rate typically 60-100 bpm (fits your 87 bpm)
   • Wide QRS with preserved T-waves
   • Often benign, seen post-MI or with reperfusion
   • Does not require treatment if hemodynamically stable

2. Supraventricular rhythm with bundle branch block

   • Pre-existing RBBB (QRS >140 ms) or LBBB (QRS >160 ms) 3
   • Could be sinus rhythm, atrial rhythm, or junctional rhythm
   • T-waves typically preserved and discordant to QRS 4

3. Junctional rhythm with aberrant conduction

   • Rate 60-100 bpm fits junctional escape
   • Wide QRS from underlying conduction disease
   • May have retrograde P-waves or AV dissociation 1

Critical ECG Features to Evaluate

Look for these specific findings:

• AV dissociation: P-waves independent of QRS complexes strongly suggests ventricular origin 3
• Fusion or capture beats: Pathognomonic for ventricular rhythm 3
• QRS morphology in V1 and V6:
  • "Typical" bundle branch block pattern suggests SVT with aberrancy
  • "Atypical" pattern suggests ventricular origin 3
• Precordial concordance: All positive or all negative QRS in chest leads suggests ventricular origin 3
• RS interval >100 ms in any precordial lead suggests VT 3

Management Approach

If Hemodynamically Stable (Most Likely Scenario)

Do NOT treat as VT at this rate. The guidelines emphasize that treatment decisions for wide-complex rhythms depend heavily on hemodynamic stability and rate 2.

Recommended steps:

1. Obtain 12-lead ECG immediately to assess morphology 1
2. Compare to prior ECG in sinus rhythm if available 3
3. Monitor closely - no immediate intervention needed if stable
4. Identify underlying cause:
   • Recent MI or reperfusion (suggests AIVR)
   • Known bundle branch block
   • Electrolyte abnormalities
   • Drug effects (antiarrhythmics, hyperkalemia) 3

Critical Pitfall to Avoid

Do NOT administer verapamil or diltiazem for wide-complex rhythms - these are contraindicated and may cause hemodynamic collapse if the rhythm is ventricular in origin 3, 2. However, at 87 bpm with preserved T-waves and hemodynamic stability, aggressive treatment is rarely indicated.

When to Treat

• Only if hemodynamically unstable (hypotension, altered mental status, chest pain) - then synchronized cardioversion 2
• If rate accelerates >100 bpm and becomes sustained VT
• If underlying reversible cause identified (treat the cause, not the rhythm)

Bottom Line

At 87 bpm with wide QRS and preserved T-waves, this represents an accelerated rhythm, not true tachycardia. Most likely AIVR or SVT with bundle branch block. Observation and ECG analysis are appropriate; aggressive antiarrhythmic therapy is not indicated unless the patient becomes unstable or the rate accelerates significantly. The presence of T-waves and relatively slow rate make this a benign presentation in most cases.