The following is a summary of “IgG4-related disease as a variable-vessel vasculitis: A case series of 13 patients with medium-sized coronary artery involvement,” published in the June 2023 issue of the Seminars in Arthritis and Rheumatism by Katz et al.

IgG4-related disease (IgG4-RD) may affect multiple organ systems, a systemic autoimmune fibroinflammatory disorder. Even though large-vessel vasculitis is a well-known manifestation of IgG4-RD, this condition is typically not considered vasculitis. The researchers sought to describe coronary artery involvement (CAI), a poorly understood vascular distribution in IgG4-RD. From a large, prospective IgG4-RD cohort, patients with IgG4-related CAI were identified. 

Imaging evidence of arterial or periarterial inflammation in any coronary artery confirmed the presence of CAI. They extracted information regarding demographics, IgG4-RD characteristics, and CAI manifestations. Thirteen (4%) of the 361 patients in the cohort had IgG4-related CAI. All subjects were male and had serum IgG4 concentrations that were significantly elevated, with a median value of 955 mg/dL (IQR: 510–1,568 mg/dL; reference: 4–86 mg/dL). At the time of CAI diagnosis, the median disease duration was 11 years (IQR: 8.23–15.0 years). Most patients (85%) had extensive coronary artery disease, with all three main coronary arteries affected in 11 patients. 

Wall thickening or periarterial soft tissue encasement (85%), stenosis (69%), calcification (69%), and aneurysms or ectasia (62%) were the coronary artery manifestations. About 5 patients (38%) were diagnosed with myocardial infarctions, 2 (15%) required coronary artery bypass grafting, and two (15%) developed ischemic cardiomyopathy. Coronary arteritis and periarteritis are prominent manifestations of IgG4-RD, which should be considered variable-vessel vasculitis, one of the most diverse varieties known. Coronary artery aneurysms, myocardial infarction, and ischemic cardiomyopathy are potential CAI complications.

Source: sciencedirect.com/science/article/abs/pii/S0049017223000240