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.