Influence of time-to-treatment, TIMI-flow grades, and ST-segment resolution on infarct size and infarct transmurality as assessed by delayed enhancement magnetic resonance imaging.
OBJECTIVE
The time-to-treatment, ST-segment resolution (STR), and TIMI-flow might be associated with infarct size (IS) and infarct transmurality in humans. Delayed enhancement magnetic resonance imaging (DE-MRI) has excellent spatial resolution to uncover these relations.


RESULTS
This study analysed 135 ST-elevation myocardial infarction (STEMI) patients randomized to prehospital fibrinolysis or prehospital initiated facilitated percutaneous coronary intervention (PCI). Reperfusion-times, 90 min STR, and TIMI-flow grades were assessed. IS at 6-month follow-up was determined as percentage of left ventricular mass (% LV). Transmurality was defined if segments exceeded > 50% DE. The median time-to-treatment was 93 min [interquartile range (IQR) 66.5; 158.8] for prehospital fibrinolysis and 85 min (IQR 60.0; 143.5) for facilitated PCI patients (P = 0.35). In facilitated PCI, the pre-interventional TIMI-flow correlated with IS [TIMI 0-1 10.8% LV (IQR 7.6; 17.3) vs. TIMI 2-3 3.9% LV (IQR 0.9; 9.6); P = 0.002] and segments with transmurality 1.5 (IQR 0.0; 3.0) vs. 0 (IQR 0.0; 1.5; P = 0.02). In a multivariable model, incomplete STR < 70% was the strongest predictor of high IS [odds ratio (OR) 6.96, P < 0.001] and transmurality (OR 5.71, P < 0.001) followed by time-to-treatment delay (OR/30 min, 1.24; P = 0.01 for high IS and 1.23, P = 0.01 for transmurality).


CONCLUSIONS
Time-to-treatment, STR, and TIMI-flow correlate with IS and transmurality underlining the assumed pathophysiological link between early flow restoration and perfusion in the infarct-related artery.
Thiele
Holger
H
Department of Internal Medicine/Cardiology, University of Leipzig-Heart Centre, Strümpellstr. 39, 04289 Leipzig, Germany. thielh@medizin.uni-leipzig.de
Kappl
Mathias J
MJ
Linke
Axel
A
Erbs
Sandra
S
Boudriot
Enno
E
Lembcke
Alexander
A
Kivelitz
Dietmar
D
Schuler
Gerhard
G
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D017023:Coronary Angiography; D003326:Coronary Circulation; D004562:Electrocardiography; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006329:Heart Conduction System; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy*; D012039:Regional Blood Flow; D013997:Time Factors; D016896:Treatment Outcome
D005343:Fibrinolytic Agents