Kinetics of ischaemia modified albumin during ongoing severe myocardial ischaemia

Release kinetics of ischaemia modified albumin (IMA) have not been described in detail and never in ongoing acute coronary syndrome. We compared IMA kinetics with early necrosis biomarkers during ST-segment elevation myocardial infarction (STEMI) and in different populations with ischaemic heart disease and healthy subjects.

We investigated 1. patients with ongoing STEMI (n=25), 2. patients with non-ST segment elevation MI (n=5), 3. patients with stable angina (n=5), and 4. healthy subjects (n=5). Groups 1-3 underwent percutaneous coronary intervention (PCI). Fourteen blood samples were collected, of which 11 were obtained during the first 24 h following PCI. Samples were analyzed for IMA, cardiac troponin T, CKMB mass, myoglobin, and heart-type fatty acid binding protein.

In the STEMI group, mean IMA increased to 16% above upper limit of normal, peaking 40 min after PCI, and nearly normalizing within 2.5 h. Relative concentrations of IMA were low compared to other cardiac biomarkers. In all other groups, changes were non-significant.

IMA is a marker of cardiac ischaemia with rapid clearance and a narrow diagnostic time window that may decrease NPV and clinical usefulness due to its dependency of short symptoms duration. Sensitivity of the assay was low compared to other markers.