Rodríguez GF, Chávez GE, Machín CWJ, Reyes HLM, González FV

Language: Spanish
References: 23
Page: 101-107
PDF size: 319.74 Kb.

ABSTRACT

Introduction and objective: Myocardial ischemia increases QT dispersion in the electrocardiogram because, in these circumstances, the action potential duration decreases in the ischemic insult area by creating a dispersion of repolarization. The rapid succession of local metabolic and ionic alterations creates favorable situations in the genesis of ventricular arrhythmias during ischemia. The objective was to determine the association of the prolonged QTc dispersion, in the acute coronary syndrome, with ventricular arrhythmias and the recurrence of acute coronary disease.
Method: A total of 194 patients with acute myocardial infarction were studied. The QT interval duration was measured in a 12-lead electrocardiogram and it was corrected for heart rate in each of these leads. The dispersion of the interval was also assessed. It was taken into account the electrocardiographic evolution of these patients in relation to the occurrence of ventricular arrhythmias and a new acute coronary syndrome in a 30-day follow-up.
Results: Among the patients who had a prolonged QT dispersion, there was a prevalence of the deceased due to ventricular fibrillation (7 cases) for 7.5%, and only 2 patients (2.2%) who suffered from this arrhythmia were discharged alive. A new acute coronary syndrome was found in 17 patients with prolonged QT dispersion, versus 8 patients with normal QT dispersion.
Conclusions: Ventricular extrasystoles was the most common arrhythmia in patients with normal QT dispersion, and ventricular fibrillation was the most common in patients with prolonged QT dispersion. Most patients who had a new acute coronary syndrome had a prolonged QTc.

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