The Prognostic Significance of Right Ventricular Dilation Assessed by Cardiac Magnetic Resonance Imaging in Heart Failure With Reduced Ejection Fraction

Background: Quantitative volumetric assessment of the right ventricle (RV) can significantly enhance risk stratification in heart failure (HF), especially with the increasing availability of cardiac MRI (CMR). The prognostic value of RV dilation measured by RV end diastolic volume indexed to body surface area (RVEDVi) is not yet well established. In this analysis, we investigate the prognostic significance of RVEDVi measured by CMR in a stable HF cohort. Methods: We conducted a retrospective analysis on the DERIVATE registry, a large cohort of stable HF patients who underwent baseline CMR and echocardiography assessment. We used the cut-off value 90ml/m 2 as the upper limit of normal for CMR-derived RVEDVi. The primary outcome was all-cause mortality (ACM), while the secondary outcome was a composite of ACM and/or heart failure hospitalization (HFH). A Cox proportional hazard model was used to evaluate the association with outcomes. Results: 2,447 patients with HF and reduced ejection fraction (HFrEF) were included, with a median follow-up time of 959 days (IQR: 560-1590). Mean LVEF was 34.0 ± 10.8, mean age was 59.8 ± 14.0 years and 42% were females. Mean RVEDVi was 75.0 ± 29.4 ml/m 2 and 23.2% had an RVEDVi >90 ml/m 2 . Elevated RVEDVi (>90 ml/m 2 ) was significantly associated with an increased risk for ACM (aHR= 1.40, 95% CI [1.17-1.67] p =0.01) and the composite of ACM/HFH (aHR= 1.40, 95% CI [1.03-1.90] p = 0.03). Conclusion: In a large cohort of HFrEF undergoing baseline CMR, elevated RVEDVi was associated with an increased risk of ACM and ACM and/or HFH, independent of LV systolic function.