Quantitative Pericardial Delayed Hyperenhancement Informs Clinical Course in Recurrent Pericarditis.

OBJECTIVES: The aim of this study was to evaluate the prognostic value of quantitative assessment of pericardial delayed hyperenhancement (DHE) among patients with recurrent pericarditis (RP).

BACKGROUND: Pericardial DHE on cardiac magnetic resonance may persist beyond the acute phase of pericarditis, suggesting continued pericardial inflammation.

METHODS: This is a retrospective cohort study of 159 patients with RP who underwent DHE imaging and had a follow-up period of more than 6 months. Pericardial inflammation was quantified on short-axis DHE sequences by contouring the pericardium, selecting normal septal myocardium as a reference region, and then quantifying the pericardial signal that was >6 SD above the reference. Our primary outcome was clinical remission; secondary outcomes were time to recurrence and recurrence rate.

RESULTS: The mean age of our patients was 46 ± 14 years, and 52% were women. During a median follow-up period of 23 months (interquartile range: 15 to 34 months), 32 (20%) patients achieved clinical remission. In the multivariable Cox proportional hazards model, lower quantitative pericardial DHE (hazard ratio: 0.77; 95% confidence interval: 0.64 to 0.93; p = 0.008) was independently associated with clinical remission. When added to background clinical and laboratory variables, quantitative pericardial DHE had incremental prognostic value over baseline clinical and laboratory variables (integrated discrimination improvement: 8%; net reclassification improvement: 36%). Furthermore, patients with a higher quantitative DHE had shorter time to subsequent recurrence (p = 0.012) and had a higher recurrence rate at 6 months (p = 0.026).

CONCLUSIONS: Quantitative assessment of pericardial DHE was associated with clinical outcomes among patients with RP and provided incremental information regarding the clinical course of patients with RP.