Abstract 14397: Myocardial Fibrosis Identified by Cardiac MRI and the Associated Cardio-Renal Dysfunction
Introduction: Clinically, the association between renal dysfunction and cardiac remodeling has been demonstrated by evidence of left ventricular hypertrophy and diastolic dysfunction. The proposed mechanism behind these findings is through the development of myocardial fibrosis. We propose that the use of cardiac magnetic MRI with a delayed- gadolinium enhancement (DGE) protocol provides an accurate and novel assessment of myocardial fibrosis in the setting of cardio-renal impairment.
Methods: Using the Mayo Clinic Cardiac MRI Database, we collected data from patients who underwent a gadolinium contrast MRI beginning in January 2006 to 2008 and had a baseline serum creatinine measurement within 30 days of the scan. The MRI data collected included left ventricular ejection fraction (LVEF), left ventricular end-diastolic mass index (LVEDMi) and the presence of delayed-gadolinium enhancement (DGE). Each patient’s estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease (MDRD) formula. MRI data for 713 patients were included in the study using these criteria.
Results: The mean age of this cohort was 54.8 ± 16.8 yrs with 42% females and the mean LVEF was 52.4 ± 13.4% with LVEDMi of 50.0 ± 18.0 g/m2. The presence of DGE (N=239) was associated with a lower eGFR (73.8 ± 21.4 ml/1.73 m2) as compared to patients with no DGE (N=474) (80.5 ± 22.8 ml/1.73 m2, p <0.001), even after adjustment for gender, LVEF and LVEDMi (p =0.005). Furthermore, there were statistically significant associations between the presence of DGE and reduced LVEF (46.7 ± 14.0%), increased LVEDMi (54.5 ± 19.4 g/m2) and elevated plasma B-type natriuretic peptide (591.0 ± 740.0 pg/ml) (p <0.001) as compared to subjects without DGE, even after adjustment for age, gender and co-morbidities.
Conclusion: This retrospective analysis demonstrates an association between the presence of myocardial fibrosis and cardio-renal dysfunction. This study adds to the growing evidence in support of myocardial fibrosis as a key component of cardiac remodeling in the setting of chronic cardio-renal impairment.
- © 2011 by American Heart Association, Inc.