Exploring cardiovascular involvement in IgG4-related disease: a case series approach with cardiovascular magnetic resonance.

Background: IgG4-related disease (IgG4-RD) is a relapsing-remitting, fibroinflammatory, multisystem disorder. Cardiovascular involvement from IgG4-RD has not been systematically characterised. In this study, we sought to evaluate consecutive patients with IgG4-RD using a detailed multiparametric cardiovascular magnetic resonance (CMR) imaging protocol.

Methods: We prospectively enrolled 11 patients with histology-confirmed IgG4-RD; with active disease at time of scan. We undertook a detailed multiparametric CMR imaging protocol at 1.5T including cine imaging, native T1 and T2 mapping, stress perfusion imaging with inline quantitation of myocardial blood flow and late gadolinium enhancement (LGE) imaging.

Results: All patients exhibited at least one abnormality on CMR imaging. Abnormal elevation of global or segmental left ventricular myocardial T1 and T2 values was present in four patients, suggesting myocardial oedema or inflammation. Abnormal LGE, suggesting myocardial scar fibrosis, was present in nine patients, with eight displaying a non-ischaemic pattern, and one showing an ischaemic pattern. Four patients fulfilled both Lake Louise Criteria for active myocardial inflammation, while a further six fulfilled one criterion. Myocardial perfusion reserve was normal in all evaluable patients. Ten patients had normal ventricular volumes, mass and systolic function. In addition, thoracic aortitis was identified in three patients who underwent ¹⁸F-flourodeoxyglucose PET/CT imaging, with resolution following anti-B-cell treatment.

Conclusions: In this cohort of patients with histology-confirmed IgG4-RD, multiparametric CMR revealed no changes in gross cardiac structure and function, but frequent myocardial tissue abnormalities. These data suggest a plausible pathophysiological link between IgG4-RD and cardiovascular involvement.