AbstractBackground: Acute aortic dissection (AOD) is associated with high mortality and early diagnosis and treatment are essential. Ischemia‐modified albumin (IMA) is a marker of myocardial ischemia whereas cardiac enzymes are released when myocardial necrosis occurs. We investigated, for the first time, whether IMA increases in AOD either at presentation or after surgery. Methods: We studied 46 consecutive patients with documented AOD; we also evaluated 13 consecutive patients with dilated ascending aortas scheduled for elective surgery and admitted for preoperative coronary angiography; 46 age‐matched normal subjects served as controls. Only patients with acute onset of symptoms were included. We evaluated IMA, cardiac enzymes, N‐terminal pro‐B‐type natriureticpeptide, albumin, C‐reactive protein (CRP), and D‐dimers on admission, 24 hr post‐operatively and 4 days post‐operatively. Duration from symptom onset to the first sample was 23±17 hr. Results: IMA did not differ between patients with AOD at presentation (93±19 U/ml), patients with chronic aneurysms (90±14 U/ml) and normal controls (91±9 U/ml). In addition, IMA did not change significantly after surgical repair. IMA, at baseline, however, correlated positively with time from symptom onset as well as CRP levels (P=0.05 and P=0.007, respectively). Conclusion: IMA is not elevated in AOD when blood sampling is performed within 23±17 hr after symptom onset nor increases after surgery. J. Clin. Lab. Anal. 24:399–402, 2010. © 2010 Wiley‐Liss, Inc.