Infarct size and myocardial salvage after primary angioplasty in patients presenting with symptoms for <12 h vs. 12-72 h.
OBJECTIVE
Primary angioplasty for ST-segment elevation myocardial infarction (STEMI) is recommended only if symptom duration is <12 h. We evaluated final infarct size (FIS) and myocardial salvage in early presenters (<12 h) vs. late presenters (12-72 h) undergoing primary angioplasty.


RESULTS
Myocardial perfusion imaging (MPI) was performed acutely to assess area at risk (AAR) before angioplasty and repeated after 30 days to assess FIS (% of LV myocardium), salvage index (% non-infarcted AAR), and left ventricular ejection fraction (LVEF). Late presenters (n = 55) compared with early presenters (n = 341) had larger median FIS [14% (inter-quartile range 3-30) vs. 7% (2-18), P = 0.005], lower salvage index [53% (27-89) vs. 69% (45-91), P = 0.05], and lower LVEF [48% (44-58%) vs. 53% (47-59), P = 0.04]. However, FIS, salvage index, and LVEF correlated weakly with symptom duration (R(2)-values <0.10). In patients with TIMI-flow 0 (n = 247), late presenters had lower salvage index than early presenters [44% (23-73) vs. 57% (42-86), P = 0.03], but substantial salvage (>50% of AAR) was observed in 41% of late presenters despite total infarct-artery occlusion.


CONCLUSIONS
FIS is larger in late presenters (>12 h) than early presenters after primary angioplasty for STEMI. However, substantial myocardial salvage can be obtained beyond the 12 h limit, even when the infarct-related artery is totally occluded.
Busk
Martin
M
Department of Cardiology, Aarhus University Hospital, Skejby, Brendstrupgaardsvej 100, Aarhus 8200, Denmark. martin.busk@ki.au.dk
Kaltoft
Anne
A
Nielsen
Søren S
SS
Bøttcher
Morten
M
Rehling
Michael
M
Thuesen
Leif
L
Bøtker
Hans E
HE
Lassen
Jens F
JF
Christiansen
Evald H
EH
Krusell
Lars R
LR
Andersen
Henning R
HR
Nielsen
Torsten T
TT
Kristensen
Steen D
SD
D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D017023:Coronary Angiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000473:pathology* / Q000628:therapy*; D055414:Myocardial Perfusion Imaging; D017410:Practice Guidelines as Topic; D012720:Severity of Illness Index; D013318:Stroke Volume / Q000502:physiology; D013997:Time Factors; D016277:Ventricular Function, Left / Q000502:physiology