Prevalence and functional impact of lipomatous metaplasia in scar tissue following myocardial infarction evaluated by MRI

Objective: To retrospectively assess the prevalence and functional relevance of lipomatous metaplasia (LM) of the left ventricle in patients with chronic ischaemic heart disease (CIHD) using cardiac magnetic resonance imaging (cMRI) with steady state free precession (SSFP) sequences. Methods: We examined 315 patients (248 male, mean age 63± 10years) with a history of CIHD by cMRI. Standard SSFP sequences were applied and results were correlated with findings from cardiac catheterisation and computed tomography. In a subgroup of patients with LM (LM+) the functional results were correlated with patients without LM (LM-) as controls matched for age, body mass index, gender and infarct size. Results: Of 315 patients, 36 showed LM. LM+ patients showed a higher tendency to develop aneurysms compared with LM-(31% vs. 17%; not significant), but no differences in ejection fraction or volumetric parameters. LM occurred significantly more often in older infarcts and patients with hyperlipoproteinaemia, while other cardiac risk factors or medication did not have a significant influence on the development of LM. Conclusions: LM is a common finding (11%) in patients with CIHD. LM does not have a significant influence on global cardiac function or ventricular size, but on local function and probably also on the development of left ventricular aneurysms.