QT dispersion within the first 6 months after an acute myocardial infarction: relationship with systolic function, left ventricular volumes, infarct related artery status and clinical outcome.
BACKGROUND
We analysed QT dispersion within the first 6 months postinfarction, its relationship with the main established risk stratifiers and its clinical value.


RESULTS
In 55 patients with a first Q-wave myocardial infarction the 12-lead electrocardiogram was scanned and digitised for analysis of QT dispersion (QT maximum-QT minimum) at first day (72 [61-96] ms), first week (69 [47-90] ms), first month (67 [46-88] ms) and sixth month (47 [40-74] ms; P<0.0001 vs. first day). Cardiac catheterization was performed at first week and at sixth month; QT dispersion was not related to ejection fraction, left ventricular volumes, infarct related artery status or contractile reserve (improvement of the infarcted area with low-dose dobutamine); no relation was found between QT dispersion decrease from first week to sixth month with regional systolic function improvement. Finally, during a mean follow-up period of 35+/-22 months QT dispersion was not independently related to clinical events.


CONCLUSIONS
QT dispersion decreases progressively during the first months after myocardial infarction. These changes should be taken into account to define cut-off values of clinical interest in this phase. This variable does not seem related to the classic prognosis predictors. In a nonselected postinfarction population it has a low clinical value.
Bodí
V
V
Cardiology Unit, Internal Medicine Department, Hospital Comarcal. Avda. Gil de Atroncillo s/n. 12500, Vinaròs, Spain. vicentbodi@hotmail.com
Sanchis
J
J
Navarro
A
A
Plancha
E
E
Chorro
F J
FJ
Berenguer
A
A
Insa
L
L
Escriche
P
P
Cabadés
F
F
Llácer
A
A
D003331:Coronary Vessels / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology*; D011379:Prognosis; D011446:Prospective Studies; D012044:Regression Analysis; D012306:Risk; D013030:Spain / Q000453:epidemiology; D016019:Survival Analysis; D013599:Systole; D016277:Ventricular Function, Left