Assessment of myocardial perfusion-CMR in left main stem disease (LMS) in the CEMARC study

Left main stem (LMS) disease is found in approximately 5% of patients with stable angina and in approximately 7% of patients presenting with an acute myocardial infarction. Accurate assessment of the degree of left main stem stenosis has important prognostic and therapeutic implications. Clinically, angiographic LMS stenosis of 50% or more is considered significant. However, it is not known how accurately myocardial perfusion imaging detects LMS disease at this severity threshold.