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Increased precordial QTc dispersion predicts ventricular fibrillation during acute myocardial infarction

A Yunus1, A M Gillis, H J Duff

  • 1Division of Cardiology, Foothills Hospital, Calgary, Alberta, Canada.

The American Journal of Cardiology
|September 15, 1996
PubMed

Insights

Patients with acute myocardial infarction and ventricular fibrillation show greater QTc interval dispersion on electrocardiograms compared to those without. This finding may help identify patients at higher risk for cardiac events.

Area of Science:

  • Cardiology
  • Electrophysiology

Background:

  • Acute myocardial infarction (AMI) is a leading cause of cardiac mortality.
  • Ventricular fibrillation (VF) is a life-threatening complication of AMI.
  • QTc interval dispersion on electrocardiograms (ECGs) may indicate arrhythmogenic substrate.

Purpose of the Study:

  • To investigate the relationship between QTc interval dispersion and the occurrence of early ventricular fibrillation in patients with acute myocardial infarction.
  • To determine if QTc interval dispersion can serve as a predictor for VF in AMI patients.

Main Methods:

  • A case-control study comparing 19 patients with AMI and early VF to 19 matched controls with AMI but without VF.
  • Electrocardiograms were analyzed to measure precordial QTc interval dispersion.

Main Results:

  • The mean precordial QTc interval dispersion was significantly greater in the AMI with VF group (73 +/- 28 ms) compared to the AMI without VF group (30 +/- 12 ms).
  • Statistical analysis showed a highly significant difference (p < 0.001).

Conclusions:

  • Elevated precordial QTc interval dispersion is associated with early ventricular fibrillation in patients experiencing acute myocardial infarction.
  • QTc interval dispersion may be a valuable non-invasive marker for identifying AMI patients at increased risk of developing ventricular fibrillation.

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