Myocardial Fibrosis quantified by T1 mapping Predicts Outcomes in Diabetes Mellitus Patients with Preserved Ejection Fraction: A cardiac MRI study (RF_FR_350)

Friday, January 31, 2025

11:10 AM – 11:20 AM East Coast USA Time

Location: Blue Room PreFunction

Presenting Author(s)

wY

wenJing Yang, PhD

Dr
Fuwai Hospital, Chinese National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, China (People's Republic)

Co-Author(s)

DZ

Di Zhou, MD

PhD
Chinese Academy of Medical Sciences and Peking Union Medical College, Fuwai Hospital, China (People's Republic)

Primary Author(s)

ML

Minjie Lu, MD

PhD
Fuwai hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, China (People's Republic)

Co-Author(s)

ML

Minjie Lu, MD

PhD
Fuwai hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, China (People's Republic)

Background: Cardiac magnetic resonance(CMR) could serve as a robust tool for the assessment of myocardial fibrosis in diabetes mellitus(DM). We aimed to evaluate the prognostic significance of CMR T1 mapping as a new noninvasive way to risk stratify patients with DM, with particular attention to its role in different clinical scenarios.

Methods: DM participants with preserved ejection fraction who completed CMR T1 mapping examinations between October 2016 and December 2022 were enrolled in this study. Extracellular volume fraction(ECV) was calculated from pre- and post-T1 mapping for the assessment of interstitial fibrosis. The primary composite outcome was cardiovascular death or heart failure hospitalization.

Results: A total of 377 DM participants (mean age, 56 years±13; 274 men) completed follow-up and were enrolled in the final analysis. During a median follow-up of 30.1 months, 58 DM patients experienced the primary outcome. The ECV was significantly higher in patients who experienced the primary outcome (30.5±3.8% vs 28.9±3.2%, P< 0.001). In univariate Cox analysis, the presence of LGE and ECV were both associated with the primary outcome(P< 0.05). In multivariate analysis, ECV remained significantly associated with the outcome in two separate models incorporating clinical variables and CMR parameters. In a final model consisting of the strongest predictors, ECV(HR: 1.105, 95% CI: 1.031 to 1.184; P=0.005) remained an independent predictor along with NT-proBNP and left ventricular end-diastolic volume index. The final multivariate model predicted outcome with a C-statistic of 0.74. In addition, the prognostic value of ECV remained consistent in all subgroups of clinical interest, such as DM patients with or without other comorbidities (hypertension and obesity), and those with or without heart failure. Kaplan-Meier survival curves showed that DM patients without LGE but with ECV≥30.48% had no significant difference in survival probability compared to patients with LGE.

Conclusion: ECV derived from CMR T1 mapping was significantly associated with the primary outcome in DM patients in different clinical scenarios. Notably, interstitial fibrosis assessed by T1 mapping could provide prognostic value independent of any form of replacement scar in DM patients.