CMR right atrial strain adds prognostic information in HFmrEF

This retrospective study included patients with HFmrEF referred for echocardiography and cardiac MRI at four tertiary centers. The development cohort comprised 1,317 patients enrolled from April 2016 to September 2024; a further 385 patients formed the validation cohort. The primary endpoint was a composite of all-cause mortality, heart-failure-related hospitalization, and cardiac transplantation. Median follow-up was 2.8 years in the development cohort and 2.1 years in the validation cohort.

The primary endpoint occurred in 243 patients in the development cohort and 72 in the validation cohort. CMR-derived right atrial conduit strain was independently associated with the outcome (hazard ratio 0.86, 95% CI 0.82–0.90; P<.001). A model combining clinical variables, conventional imaging measures, and right atrial strain had C-indices of 0.80 and 0.81 in the two cohorts, respectively. The findings indicate incremental prognostic information, but the retrospective design and use of a composite outcome limit conclusions about how this measure should affect clinical management.