Cardiac MRI for assessment of myocardial perfusion: Current status and future perspectives

Cardiac magnetic resonance imaging (MRI) has recently been applied successf ully to the assessment of myocardial perfusion. Cardiac MRI offers potentia l advantages over radioisotopic techniques because it provides superior spa tial resolution, does not use ionizing radiation, and has no imaging orient ation constraints. Current MRI perfusion approaches measure the alteration of regional myocardial magnetic properties after the intravenous injection of contrast agents. Several studies have validated the ability of perfusion MRI to detect the presence of significant coronary artery stenoses by dete cting decreased signal intensity upslope or reduced maximal enhancement in the ischemic territories, Perfusion MRI has also been shown to assess accur ately the extent of injury after a myocardial infarction and the presence o f myocardial viability. With the introduction of newer contrast media, tech nologic improvements on MRI hardware and software, and the enhancement of q uantitative analysis, MRT is likely to become a clinical tool for assessmen t of myocardial perfusion imaging in the near future.