Unrecognized myocardial infarction assessed by cardiac magnetic resonance imaging is associated with adverse long-term prognosis.

BACKGROUND:Unrecognized myocardial infarctions (UMIs) are common. The study is an extension of a previous study, aiming to investigate the long-term (>5 year) prognostic implication of late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) detected UMI in patients with suspected stable coronary artery disease (CAD) without previously diagnosed myocardial infarction (MI). METHODS:In 235 patients with suspected stable CAD without previous MI, LGE-CMR imaging and coronary angiography were performed. LGE with a subendocardial component detectable in more than one imaging plane was required to indicate UMI. The stenosis grade of the coronary arteries was determined, including in the artery supplying an infarcted area. Stenosis ≥70% stenosis was considered significant. Patients were followed for 5.4 years in mean regarding a composite endpoint of cardiovascular death, MI, hospitalization due to heart failure, stable or unstable angina. RESULTS:UMI were present in 58 of 235 patients (25%). Thirty-nine of the UMIs were located downstream of a significant coronary stenosis. During the follow-up 40 patients (17.0%) reached the composite endpoint. Of patients with UMI, 34.5% (20/58) reached the primary endpoint compared to 11.3% (20/177) of patients with no UMI (HR 3.7, 95% CI 2.0-6.9, p