Comparison of infarct size changes with delayed contrast-enhanced magnetic resonance imaging and electrocardiogram QRS scoring during the 6 months after acutely reperfused myocardial infarction.
BACKGROUND
Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium that has infarcted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size.


OBJECTIVE
The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases.


METHODS
In 31 patients (26 men, age 56 +/- 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were taken from 1 to 2 days (acute), 1 month (healing), and 6 months (chronic) after the MI. Selvester QRS scoring was used to estimate the infarct size from the ECG.


RESULTS
The correlation values between infarct size measured by DE-MRI and QRS scoring range from 0.33 to 0.43 higher for anterior than inferior infarcts. The infarct size estimated by QRS scoring was larger (about 5% of the left ventricle) than infarct size by DE-MRI acute and 1 month, but at 6 months, there was no difference. In about half of the patients, the QRS score agreed with DE-MRI in change of infarct size from acute to 6 months.


CONCLUSIONS
In conclusion, the Selvester QRS scoring system is in half of the patients with reperfused first time MI in good accordance with DE-MRI in identifying a decrease or no change in the extent of left ventricle occupied by infarction in the acute and chronic phases.
Bang
Lia E
LE
Department of Cardiology, The Heart Center, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark. Lia@dadlnet.dk
Ripa
Rasmus S
RS
Grande
Peer
P
Kastrup
Jens
J
Clemmensen
Peter M
PM
Wagner
Galen S
GS
D003287:Contrast Media; D003936:Diagnosis, Computer-Assisted / Q000379:methods*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015428:Myocardial Reperfusion Injury / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media