Short- and long-term prognostic value of the corrected QT interval in the non-ST-elevation acute coronary syndrome.
OBJECTIVE
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 > or =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 > or =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 > or =450 milliseconds (5% vs 24%; P < .0001) but had no significant effect in AQTc<450 milliseconds.


CONCLUSIONS
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.
Jiménez-Candil
Javier
J
Department of Cardiology, University Hospital, Salamanca, Spain. jjimenezcandil@yahoo.es
González
Ignacio Cruz
IC
González Matas
José M
JM
Albarrán
Carmen
C
Pabón
Pedro
P
Moríñigo
José Luis
JL
Ledesma
Claudio
C
Martín
Francisco
F
Diego
Maximiliano
M
Martín-Luengo
Cándido
C
D000368:Aged; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000453:epidemiology*; D003936:Diagnosis, Computer-Assisted / Q000379:methods / Q000706:statistics & numerical data; D004562:Electrocardiography / Q000379:methods* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008133:Long QT Syndrome / Q000175:diagnosis* / Q000453:epidemiology*; D008297:Male; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000453:epidemiology*; D011379:Prognosis; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D012680:Sensitivity and Specificity; D013030:Spain / Q000453:epidemiology