Coronary Arteritis in Indolent IgG4 Disease

Area of Science:

• Cardiovascular Imaging
• Immunology
• Rheumatology

Background:

• IgG4-related disease (IgG4-RD) is a multisystem fibroinflammatory condition.
• Coronary artery involvement in IgG4-RD, or IgG4-related coronary arteritis, is rare and challenging to diagnose.
• Patients may present with nonspecific symptoms or be asymptomatic, complicating early detection.

Purpose of the Study:

• To highlight the diagnostic challenges of IgG4-related coronary arteritis.
• To emphasize the role of advanced imaging in managing this condition.
• To present a case of successful treatment guided by imaging and serological markers.

Main Methods:

• Coronary CT angiography (CCTA) for initial assessment of coronary artery thickening.
• Cardiac MRI to evaluate wall thickening and inflammation.
• PET/CT with 18F-fluorodeoxyglucose (FDG) to assess metabolic activity and inflammation.
• Serological tests for immunoglobulin G4 (IgG4) and erythrocyte sedimentation rate (ESR).

Main Results:

• Incidental coronary artery thickening detected on CCTA.
• Progressive thickening and FDG avidity on serial imaging over eight years.
• Elevated serum IgG4 and ESR levels confirmed.
• Significant reduction in coronary wall thickening and FDG uptake following immunosuppressive therapy (prednisone and rituximab).

Conclusions:

• IgG4-related coronary arteritis poses diagnostic difficulties, often presenting incidentally.
• Multimodality advanced imaging (CCTA, cardiac MRI, FDG-PET/CT) is essential for diagnosis, surveillance, and assessing treatment response.
• Prompt diagnosis and treatment are crucial, even in asymptomatic individuals, to prevent potential cardiovascular complications.