Short- and long-term prognostic value of the corrected QT interval in the non–ST-elevation acute coronary syndrome.

Abstract: Background and purpose: Myocardial ischemia prolongs the QTc interval. Very little data exists about its prognostic implications in the non–ST-elevation acute coronary syndromes (NST-ACS). Methods: This is and observational and prospective study in which we evaluated the prognostic implications of the QTc obtained at admission (AQTc) in the short- and long-term of the NST-ACS. The median of the follow-up was 17 months. Results: AQTc correlated adequately with the incidence of adverse events in the short- and long-term (P < .001), with the best cut-off point in 450 milliseconds. Patients with AQTc ≥450 presented higher frequency of in-hospital death: 8.8% vs 1.2%; P = .001, and MACE (death, recurrent ischemia, or urgent coronary revascularization): 72% vs 25%; P < .001. In a Cox regression analysis, we found 3 independent predictors of cardiovascular death after discharge: AQTc ≥450 (14.7% vs 2.1%; P < .0001), age >65 years and left ventricular ejection fraction <40%. Coronary revascularization reduced the risk of posthospitalary cardiovascular death in AQTc ≥450 milliseconds (5% vs 24%; P < .0001) but had no significant effect in AQTc<450 milliseconds. Conclusion: These findings provide a new evidence supporting the prognostic value of the AQTc in predicting unfavorable events in the short- and long-term of the NST-ACS. [Copyright &y& Elsevier]