Background Late gadolinium enhancement (LGE) imaging is an established technique for the assessment of myocardial replacement fibrosis/scar. The presence of mid-wall LGE has been described in ∼30% of patients with dilated cardiomyopathy (DCM) of non-ischemic aetiology and is known to be associated with poor clinical response to pharmacological therapy and worse outcome. Conversely, little is known regarding the clinical significance of additional mid-wall LGE in patients with ischemic cardiomyopathy (ICM). The aim of the present study was therefore to investigate the prevalence and clinical/imaging correlates of mid-wall LGE in a consecutive cohort of patients with ICM.
Methods The UHSM-redCAP database was searched for patients with ICM (defined as the presence of LV ejection fraction <50% in the context of multivessel disease and/or previous myocardial infarction) who had clinically-indicated CMR with LGE imaging for the assessment of LV volumes, LV regional/global systolic function and presence/extent of myocardial replacement fibrosis/scar.
Results A total of 606 consecutive patients with ICM were identified and included in the study. Mean age of the study population was 64±11 years and 85% of the patients were males. Mid-wall LGE was observed in 34 (6%) patients. No significant difference in age (64±11 vs. 65±11 years), male gender (85% vs. 94%), and prevalence of NYHA functional class 3–4 (29% vs. 32%) was observed between ICM patients without vs. with additional mid-wall LGE. However, ICM patients with mid-wall LGE had larger LV end-diastolic volume (261±79 ml vs. 220±60 ml; p<0.001), larger LV end-systolic volume (176±74 ml vs. 140±54 ml; p<0.001) and lower LV ejection fraction (34%±8% vs. 38±9%; p=0.019).
Conclusion Additional mid-wall LGE is present in a small proportion (6%) of patients with ICM and is a marker of worse LV dilatation and systolic function. The clinical meaning of this finding (i.e. dual pathology vs. epiphenomenon of severe LV dilatation and wall stress) and its implication with respect to outcome remains to be determined.
Funding acknowledgement This research was funded by the NIHR Leicester Cardiovascular Biomedical Research Centre.