Abstract 17372: Factors Associated with Interstitial Fibrosis by CMR T1 Mapping After 10 Years: The Multi-Ethnic Study of Atherosclerosis (MESA)

Abstract

Introduction: Cardiac magnetic resonance (CMR) using T1 mapping (T1map) has the potential to quantify diffuse myocardial fibrosis. The purpose of this study was to describe clinical and imaging determinants of interstitial myocardial fibrosis evaluated in a large-scale multicenter study (Multi-Ethnic Study of Atherosclerosis, MESA). Materials and

Methods: All MESA participants were free of cardiovascular disease at the baseline exam (2000-2002) and traditional risk factors, image biomarkers, and CMR parameters were measured at that time. The 1,230 participants underwent CMR exam as part of a 10 year follow-up exam (2010-2012). Gadolinium contrast (0.15mmol/kg) was administrated and single slice T1 mapping was performed at the mid-ventricular level before and after (12 and 25 minutes) the infusion using a Modified Look Locker Inversion Recovery (MOLLI) sequence. The partition coefficient (λ) was determined as ΔR1myo / ΔR1blood. Multivariable regression analysis was performed for the traditional risk factors, packyears of smoking and imaging biomarkers, adjusting for study site.

Results: The participants’ mean age was 67.8 ± 8.8 years old and 51.2% were men. The mean partition coefficient was 45.2±4.4%. In the first multivariable model, older age, female gender, current smoking status and higher packyears were independent determinants of interstitial fibrosis. With the addition of imaging variables, higher age (β=0.9 % per year) was associated with higher interstitial fibrosis. Female gender (β=1.68) was more likely to have diffuse myocardial fibrosis (p<0.001). From the image parameters, ascending aorta diameter was significantly associated with diffuse fibrosis (p<0.001) (Table).

Conclusion: Higher age, female gender, current smoking status and aortic diameter were independently associated with interstitial myocardial fibrosis by T1 mapping CMR in MESA.