Abstract 14588: Quantification of Diffuse Myocardial Fibrosis by Cardiac Magnetic Resonance Contrast-Enhanced T1 Mapping is Associated with Subclinical Myocardial Dysfunction in Diabetic Heart Disease
Background: Diabetic patients have increased interstitial myocardial fibrosis indicative of diabetic heart disease. Magnetic resonance imaging (MRI) T1 mapping can quantify the burden of interstitial fibrosis. The present study aims to quantify the burden of interstitial fibrosis in diabetic patients with normal left ventricular (LV) ejection fraction (EF), and correlate it with myocardial functional assessment by echocardiographic 2-dimensional speckle tracking analysis.
Methods: A total of 50 diabetic patients (mean age 51 ± 10 years, 54.0% male) with normal LVEF and no MRI delayed enhancement suggestive of previous myocardial infarction were prospectively recruited. LV volumes, mass and EF were quantified by MRI. The burden of interstitial fibrosis was quantified by global contrast-enhanced myocardial T1 time using MRI T1 mapping. Myocardial function was quantified by global longitudinal strain using 2-dimensional echocardiography.
Results: Mean end-diastolic volume index, end-systolic volume index and LVEF were 79.1 ± 14.4 mL/m2, 33.3 ± 7.6 mL/m2, and 58.1 ± 4.6% respectively. There was a wide range of interstitial fibrosis as reflected by the global contrast-enhanced myocardial T1 time (425 ± 72 ms, range 271 – 604 ms). There was no correlation between the burden of interstitial fibrosis and LVEF (r = 0.14, p = 0.32). However, there was good correlation between the burden of interstitial fibrosis and global longitudinal strain (r = −0.73, p < 0.001). Multivariate analyses demonstrated that the burden of interstitial fibrosis was the strongest independent determinant of LV myocardial function (β = −0.701, p < 0.001).
Conclusions: MRI T1 mapping can quantify the burden of interstitial myocardial fibrosis in diabetic patients. A higher burden of interstitial fibrosis was associated with more impaired longitudinal myocardial function.
- © 2010 by American Heart Association, Inc.