The purpose of this study is to determine whether intra-coronary adenosine or sodium
nitroprusside (SNP) delivered selectively via a thrombus aspiration catheter (or if
unsuccessful via a coronary microcatheter) following thrombus aspiration in Primary
Percutaneous Coronary Intervention (P-PCI) reduces microvascular obstruction (MVO) parameters
and infarct size as measured with cardiac MRI, compared with standard treatment following
thrombus aspiration in patients presenting with ST-elevation myocardial infarction (STEMI).