First Multiparametric Cardiovascular Magnetic Resonance Study Using Ultrasmall Superparamagnetic Iron Oxide Nanoparticles in a Patient With Acute Myocardial Infarction
New Vistas for the Clinical Application of Ultrasmall Superparamagnetic Iron Oxide
A 50-year-old man presented with acute chest pain that had started about 6 hours prior to admission to our emergency department. His resting ECG revealed an ST-elevation myocardial infarction with typical ST-segment elevation in the leads V1 through V4 and reciprocal ST-segment depression. Consequently, immediate coronary angiography was performed and revealed a proximally occluded left anterior descending artery (Figure 1). The left anterior descending artery was recanalized and a bare-metal stent was implanted. Postinterventional blood analysis revealed a peak total creatine kinase level of 2962 U/L (normal, <190 U/L), a peak creatine kinase–muscle-brain type level of 231 U/L (normal, <25 U/L), a peak high-sensitivity troponin T level of 5705 pg/mL (normal, <14 pg/mL), and a slightly elevated N-terminal pro-brain natriuretic peptide level of 882 pg/mL (normal, <450 pg/mL).
After coronary angiography, the patient was enrolled in an ongoing clinical trial (Non-invasive myocardial inflammation imaging study 2 [NIMINI-2]) that is attempting to evaluate whether myocardial infarct imaging using ultrasmall superparamagnetic iron oxide nanoparticles (USPIO) and multiparametric cardiovascular magnetic resonance (CMR) techniques allow an improved characterization of infarct as well as peri-infarct pathology (compared with conventional gadolinium-based necrosis/fibrosis imaging). Therefore, multiparametric CMR studies were performed before and after intravenous ferumoxytol (Feraheme, a USPIO; 17 mL IV=510 mg Fe) administration. The first CMR (pre-Feraheme) was performed 3 days after presentation with acute ST-elevation myocardial infarction. Serial CMR studies were then performed 6 hours, 24 hours, 48 hours, 96 hours, and 3 months after intravenous Feraheme administration (post-Feraheme). Only the first (pre-Feraheme) and last CMR study (3 months post-Feraheme) …