Coronary Periarteritis and Pericardial Thickening Could Be Predictors for Coronary Artery Events Complicated by IgG4-Related Disease

BACKGROUND: IgG4-related disease (IgG4-RD) is a systemic disease characterized by serum IgG4 upregulation, massive infiltration of IgG4-positive plasma cells, and storiform fibrosis, which results in nodules or thickening of the involved organs. Cardiologists have recently recognized that IgG4-RD can be complicated by coronary artery events (CAEs); however, the mechanisms and clinical characteristics of this phenomenon are unknown. We evaluated the clinical signs of patients with coronary periarteritis (CP), aortic periarteritis (AP), and pericardial thickening, which are complications of IgG4-RD, to determine the contributing factors. METHODS: We retrospectively examined 19 patients with IgG4-RD who attended or consulted a cardiologist in our department at the University of Tokyo Hospital between January 1, 2004, and December 31, 2021. RESULTS: The frequency of CAEs was significantly higher in the CP group than in the non-CP group. Furthermore, the CP group had significantly lower event-free survival than the non-CP group (log-rank test, P = 0.008). However, the frequency of incidents and event-free survival for CAEs after IgG4-RD diagnosis did not differ significantly between the AP and non-AP groups. Although no statistically significant difference was present between the frequency of CAEs for those with vs without pericardial thickening, the group with pericardial thickening had significantly worse event-free survival than the group without pericardial thickening (log-rank test, P = 0.017). CONCLUSIONS: The incidence and clinical course of CAEs complicated by IgG4-RD could be predicted by identifying CP and pericardial thickening in IgG4-RD but not AP.