Abstract 12098: Early Detection of Hemorrhagic Myocardial Infarction With Multidetector Computed Tomography Immediately After Primary Angioplasty in Patients With Acute Myocardial Infarction

Abstract

Background: Recent studies have shown that transmural delayed enhancement pattern on multidetector computed tomography (MDCT) without iodine re-injection immediately after primary percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction (STEMI) was correlated with non-viable myocardium. Non-invasive assessment of microvascular obstruction (MVO) and interstitial myocardial hemorrhage by cardiovascular magnetic resonance (CMR) provides a specific biomarker of severe ischemia-reperfusion injury. The aim of this study was to determine whether MDCT enhancement patterns immediately after PCI was related to the presence of myocardial hemorrhage determined by T2*-CMR in patients with STEMI.

Methods: The study population consisted of 54 consecutive patients with a first STEMI successfully treated with PCI. 64-slice MDCT without iodine re-injection was performed immediately after PCI. Myocardial enhancement was considered transmural when involving≥75% of myocardial thickness (n=29), subendocardial (<75%, n=18)) or normal (n=7). T2*-CMR performed within 3 days after primary PCI was used to identify the presence of reperfusion hemorrhage and contrast enhancement was used to detect and quantify MVO. A semiquantitative scale score was defined for the 17 left ventricular segments to assess the extent of delayed enhanced area determined by MDCT.

Results: Thirty-seven/54 (69%) patients had MVO and 27 (50%) of them showed myocardial hemorrhage. Patients with MVO and hemorrhagic myocardial infarction were more frequently observed in patients with transmural delayed enhancement pattern by MDCT compared to those without transmural pattern (97% vs 36%, p<0.0001; 79% vs 16%, p<0.0001, respectively). The total sizes of LGE and MVO correlated with the extent of delayed enhancement of MDCT (r²=0.61, p<0.0001; r²=0.43, p<0.0001, respectively).

Conclusion: Transmural myocardial delayed enhancement immediately after primary PCI without iodine re-injection for STEMI is a reliable method for evaluating severe ischemia-reperfusion injury, followed by hemorrhagic myocardial infarction.