IgG4 related coronary artery involvement: A scoping review of the literature

Immunoglobulin (Ig)G4-related disease (IgG4-RD) can affect any organ, but coronary artery involvement (CAI) is a potentially life-threatening manifestation of this disease. In this scoping review, we critically appraised the literature on IgG4-related CAI, aiming to explore clinical, radiological and histopathological characteristics as well as treatment strategies and prognosis.

A comprehensive search was performed on January 02, 2025 in PubMed® to identify studies describing individuals with IgG4-related CAI, including both coronaritis (true arteritis of the coronary vessel wall) and periarteritis (peri-coronary involvement), and considering case reports, case series, retrospective cohort studies and observational studies. Two reviewers independently conducted the revision of literature under the guidance of the methodologist to identify eligible studies. Data extraction included clinical presentation, imaging findings, histopathology, treatment, and outcomes. Given the heterogeneity of the studies, descriptive statistical analysis was used whenever possible to summarise the data.

Out of 964 screened references, 143 articles met the above-mentioned inclusion criteria. Most CAI cases were included in case reports (90.2 %), 7 % in case series and 2.8 % in retrospective cohort studies or observational studies. CAI predominantly affected males in the sixth decade of life and frequently coexisted with aortic and large vessel involvement. All segments of the coronary arterial tree could be involved, even the smallest branches. Images detected by various methods revealed several types of lesions: stenosis, wall-thickening, aneurysm, ectasia, pseudotumor, pseudoaneurysm, dissection, and soft tissue masses. Increase serum IgG4 levels and increased inflammatory markers were reported. Histopathology was consistent with IgG4-RD in all coronary samples obtained. Glucocorticoid therapy, alone or combined with immunosuppressants and/or surgical interventions, was the most commonly reported treatment. Rituximab seemed to be an effective therapy for IgG4-related CAI even without associated glucocorticoids. Despite treatment, relapse and progression of coronary lesions were noted in some cases.

Early identification and multidisciplinary management og IgG4-related CAI are crucial to reduce morbidity and mortality. Available data on the response to various treatments are limited, as dedicated coronary artery imaging was not consistently obtained soon enough after treatment to assess response. In addition, long-term follow-up was not available for all patients. Further studies are required to understand the real prevalence, natural history, optimal diagnostic strategies, and therapeutic approaches for this serious condition.