Myocardial ischemia as presenting manifestation of IgG4-related disease: a case-based review.

Coronary involvement in IgG4-related disease (IgG4-RD) has been scarcely reported, and myocardial ischemia as its presenting feature is even rarer. Here, we describe an additional case with novel and relevant observations. The patient was a previously healthy, middle-aged woman who presented to the clinic with new-onset typical angina. One tumefactive lesion encasing the left anterior descending artery was found during her workup. The most common underlying malignancies with secondary cardiac involvement were rationally ruled out. Symptoms persisted despite medical treatment, and she was therefore referred to surgery. Tumor excision was successfully performed, and she received coronary bypass grafting. IgG4-related coronary arteritis with pseudotumor formation was subsequently diagnosed following the comprehensive diagnostic criteria. This condition was clinically classified as active and circulating plasmablasts were found to be increased (5480/mL), even when these were determined 38 days after surgery. A PET/CT revealed an additional hypermetabolic lymph node. She was therefore treated with rituximab as induction therapy (two 1000 mg doses, administered 15 days apart). Three months later, her disease remained clinically inactive. Circulating plasmablasts were repeated and these had dropped to 0/mL. We thereafter review the current and pertinent literature on the topic, emphasizing the previous cases with similar presenting features (n = 7). We lastly suggest that IgG4-RD should be part of the differential diagnosis of any patient with tumefactive lesions surrounding the coronary arteries, since it can initially presented as sudden cardiac death.