Localization of prior myocardial infarction by repolarization variables.
BACKGROUND
To find quantitative, automatically applicable electrocardiographic (ECG) variables for detecting prior myocardial infarction (MI) in different myocardial regions.


METHODS
Observational study. Body surface potential mapping (BSPM) was recorded at rest, and automatically analyzed with regard to ECG parameters, blinded to the clinical characteristics of the study subjects, 144 patients with prior MI and 75 healthy controls. MI location was determined by cine angiography or echocardiography as anterior (66 patients), inferoposterior (89 patients), and lateral (15 patients). Patients' 12-lead ECG was interpreted according to Minnesota code (Q-wave MI in 97 patients). The QRSSTT, QRS, and STT integrals, and the T-apex amplitude in detecting prior anterior and inferoposterior MI were analyzed.


RESULTS
The T-apex amplitude, QRSSTT integral, and STT integral were functional in detecting MI in all tested locations on a single-lead basis, with areas under receiver operating characteristic curves (AUC) of over 90% (p<0.001) in optimal sites. In the best leads AUC for the QRSSTT integral in anterior MI was 93% (CI 87-99%) and for the inferoposterior MI 92% (CI 88-97%). These repolarization variables outperformed the Minnesota code in all tested MI locations. They were also able to distinguish between anterior and inferoposterior MI with an AUC of >85% (p<0.001).


CONCLUSIONS
Quantitative, automatically applicable single-lead repolarization variables detect prior MI irrespective of its location. They may simplify the screening for and localization of old infarctions as compared to the conventional ECG methods.
Vesterinen
Paula
P
Division of Cardiology, Helsinki University Central Hospital, Helsinki, Finland. paula.vesterinen@kolumbus.fi
Väänänen
Heikki
H
Stenroos
Matti
M
Hänninen
Helena
H
Korhonen
Petri
P
Tierala
Ilkka
I
Husa
Terhi
T
Mäkijärvi
Markku
M
Toivonen
Lauri
L
D019540:Area Under Curve; D018780:Body Surface Potential Mapping; D016022:Case-Control Studies; D002932:Cineangiography; D016002:Discriminant Analysis; D004452:Echocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000503:physiopathology*; D012372:ROC Curve; D012680:Sensitivity and Specificity