Intracoronary thrombus will be retrieved by standard aspiration catheter, washed with saline and stored on formalin as advised by the Department of pathology, OUS Ullevål. A specific protocol for morphological and immunohistochemical methods is prepared and has been shown suitable in a pilot study on 5 patients. Assessment of coronary TIMI flow and peripheral blush grade after thrombus aspiration and PCI will be done. At the same time, peripheral venous blood will be drawn, processed and stored at -80˚C for later analyses. Demographic variables will be recorded.