Abstract 18894: Global Left Ventricular Remodeling Characteristics are More Important than Scar Extent and Location for Prediction of Severe Mitral Regurgitation in Advanced Ischemic Cardiomyopathy

Abstract

BACKGROUND: Mitral regurgitation (MR) is particularly common in patients with ischemic cardiomyopathy (ICM) following an acute myocardial infarction where its presence is independently associated with worse mortality. In patients with advanced ICM, unfavorable LV remodeling causes geometrical changes leading to MR development. The best management of these patients remains unclear. Whether magnetic resonance imaging (MRI) with its higher spatial resolution and scar information can add further insights remains unknown.

HYPOTHESIS: We hypothesized that MRI assessment of LV remodeling as well as scar extent, location and papillary muscle involvement could aid in the prediction of severe MR in patients with advanced ICM.

METHODS: A total of 452 patients with LVEF ≤ 40% and ≥ 70% stenosis in ≥ 1 coronary artery, history of CABG or PCI with transthoracic echocardiogram and MRI studies within 7 days were included (median=1 day). Quantitative MR assessment was performed as per ASE guidelines. LV volumes, sphericity and LVEF were calculated from cine MRI images. LV scar was measured ∼ 10-15 minutes after gadolinium injection, using phase-sensitive inversion recovery sequence.

RESULTS: The mean age was 62 ± 10 years and males represented 75%. LVEF, LV end-systolic volume index were 23 ± 0.5% and 115 ± 2 ml/m²respectively. MR was classified as: trivial/mild (63%), moderate (22%) or severe (15%). Multinomial logistic regression analysis revealed that LV remodeling changes were independent predictors of severe MR but not scar extent, location and/or papillary muscle involvement (Table).

CONCLUSION: In ICM patients with severely dilated LV, contrary to prior studies showing the importance of regional LV remodeling and scarring, global LV remodeling appears to be more important in predicting presence of severe MR. These findings further confirm the dynamic nature of the remodeling process and highlight its importance as future target for management of these patients.