Short- and long-term changes in myocardial function, morphology, edema, and infarct mass after ST-segment elevation myocardial infarction evaluated by serial magnetic resonance imaging.
BACKGROUND
Knowledge of the natural course after an ST-elevation myocardial infarction (STEMI) treated according to guidelines is limited because comprehensive serial magnetic resonance imaging (MRI) of systolic left ventricular function, edema, perfusion, and infarct size after STEMI has not been undertaken. The aim of this study was to evaluate effects of therapy for STEMI on left ventricular function and perfusion and to test the hypothesis that myocardial perfusion by MRI predicts recovery of left ventricular function.


METHODS
Cine MRI, edema, first-pass perfusion, and late enhancement imaging were performed in 58 patients at day 2 and at 1 and 6 months after successful primary percutaneous coronary stent intervention for STEMI.


RESULTS
Ejection fraction increased 6.3% during the first month (P < .001) and 1.9% from 1 to 6 months (P < .06), indicating a maximal recovery very early after the infarction. The systolic wall thickening in the infarct area almost doubled (P < .001), the perfusion of infarcted myocardium increased approximately 50% (P = .02), and perfusion improved in 72% of patients. Edema decreased with a mean of 2 segments (P < .001) during the first month and another 2.5 segments from 1 to 6 months (P < .001). Infarct size decreased to 1 month (P = .01) and was unchanged from 1 to 6 months (P = .5). Baseline perfusion did not predict improvement in ejection fraction (r = 0.2, P = .2) but did predict regional systolic function (P = .03).


CONCLUSIONS
Left ventricular function, perfusion, and infarct mass recovered substantially after STEMI, with the main part of the change within the first month. First-pass perfusion at rest appeared to predict regional ventricular recovery.
Ripa
Rasmus Sejersten
RS
Department of Cardiology, The Heart Centre, University Hospital Rigshospitalet, Copenhagen, Denmark.
Nilsson
Jens Christian
JC
Wang
Yongzhong
Y
Søndergaard
Lars
L
Jørgensen
Erik
E
Kastrup
Jens
J
D003326:Coronary Circulation; D004311:Double-Blind Method; D004487:Edema / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D009206:Myocardium / Q000473:pathology*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology*; D013997:Time Factors; D016276:Ventricular Function / Q000502:physiology*