Multipolar QRST isointegral maps and QT dispersion in old myocardial infarction.
Chronic myocardial infarction (CMI) may create, due to structural heterogeneity, abnormal electrophysiological substrates which trigger re-entrant life-threatening ventricular arrhythmias.


METHODS
Electrical instability is assessed using body surface mapping (BSM) [multipolar isointegral QRST maps (mp I(QRST))] and 12-lead ECG (QT dispersion: QTd: the difference between maximal and minimal QT interval). The aim was to find the relation between mp I(QRST) and QTd in CMI patients.


RESULTS
The 32 CMI patients, underwent 12-lead ECG and 64-lead BSM. The 80% (25) of the patients had mp I(QRST) maps. QTd was larger in patients with mp than those with dipolar maps (dp): 170 +/- 20 ms in mp vs 94 +/- 19 ms in dp, respectively. The latter, mp I(QRST) was associated with a decrease of maximum and a stronger minimum.


CONCLUSIONS
Multipolar I(QRST) is associated with a loss of maximum values and increased absolute values of the minimum in CMI patients. I(QRST) and QTd provide similar information in predicting postinfarction arrhythmia risk.
Department of Pathophysiology, University of Medicine and Pharmacy "Victor Babes", Timisoara, Romania. ioanamozos@umft.ro
Ioana
I
Mozos
M
M
Hancu
N
N
Jost
A
A
Cristescu
D000368:Aged; D001145:Arrhythmias, Cardiac / Q000175:diagnosis; D018780:Body Surface Potential Mapping / Q000295:instrumentation / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000503:physiopathology* / Q000534:rehabilitation*; D011379:Prognosis; D013997:Time Factors