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Negative concordant T waves during paced ventricular rhythm: An honest enemy is better than a false friend

Irene di Matteo1, Pasquale Crea2

  • 1Interventional Cardiology Unit, De Gasperis CardioCenter -ASST Grande Ospedale Metropolitano Niguarda, Milan.

Journal of Electrocardiology
|March 28, 2017
PubMed

Insights

Diagnosing heart attacks in pacemaker patients is difficult. Sgarbossa criteria and ECG comparisons help detect myocardial ischemia, but cardiac memory can cause errors. Adjusting AV delay may clarify diagnosis.

Area of Science:

  • Cardiology
  • Medical Diagnostics
  • Electrophysiology

Background:

  • Electrocardiogram (ECG) interpretation for myocardial infarction and ischemia is complicated in pacemaker patients.
  • Established criteria like Sgarbossa's for left bundle branch block (LBBB) have shown validity in pacemaker recipients.
  • Recent research links concordant negative T waves during ventricular pacing to acute myocardial injury.

Observation:

  • Comparison with prior ECGs is essential for accurate diagnosis.
  • Cardiac memory can persist during fusion beats, creating misleading concordance between negative T waves and QRS axis.
  • This phenomenon may lead to erroneous suspicion of acute myocardial injury.

Findings:

  • The Sgarbossa criteria are applicable for diagnosing myocardial ischemia in pacemaker patients.
  • Concordant negative T waves in ventricular paced rhythm can indicate acute myocardial injury.
  • Cardiac memory effects during fusion beats can mimic ischemia, necessitating careful ECG review.

Implications:

  • Accurate ECG interpretation is vital for timely intervention in pacemaker patients with suspected heart attack.
  • Understanding artifacts like cardiac memory is crucial to avoid misdiagnosis.
  • Modifying atrioventricular (AV) delay may serve as a diagnostic tool to differentiate true ischemia from artifactual findings.

Keywords:
Cardiac memoryMyocardial ischaemiaNegative T wavesPaced ventricular rhythm

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