Investigating the cardiac manifestations of IgG4-related disease using cardiac magnetic resonance imaging
Henry JA., Xavier R., Selvaraj E., Burrage MK., Thomas KE., Lukaschuk E., Ferreira VM., Piechnik S., Neubauer S., Rider OJ., Culver E., Lewis AJM.
Abstract Introduction IgG4-related disease (IgG4-RD) is a relapsing-remitting immune-mediated condition that affects multiple organ systems. Case reports of suspected cardiovascular involvement in IgG4-RD have emerged though no study has systematically assessed the cardiovascular phenotype of IgG4-RD using cardiac magnetic resonance (CMR) imaging. Purpose We systematically assessed patients with IgG4-RD using CMR to identify the cardiovascular manifestations, and compared them to controls. Methods We recruited 11 patients with histologically-confirmed IgG4-RD (6 female, 61±11 years, 9 with active disease (8 with pancreatic involvement, 3 parotid, 5 bile ducts, 5 kidneys and 3 cardiovascular)). Patients underwent CMR at 1.5T including cine, myocardial tagging, native T1-mapping, late gadolinium enhancement (LGE), extracellular volume (ECV) and quantitative stress perfusion mapping. Results were compared to 10 healthy controls with no cardiac disease (50% female, 35±8 years). Results are presented as mean ± standard deviation (SD) unless otherwise stated. Results Patients with IgG4-RD had similar cardiac geometry to the reference group (Table 1), with similar biventricular and bi-atrial volumes. However, despite similar biventricular ejection fractions compared to controls (patient LVEF: 55-67%, RVEF: 51-65%), IgG4-RD patients showed significantly reduced global longitudinal strain (GLS) (-16.8 ± 2.3% vs -18.7 ± 1.6%, p=0.045). Furthermore, 64% (7/11) of IgG4-RD patients showed LGE, 6 of whom showed non-ischaemic patterns (Figure 1). Male IgG4-RD patients (n=5) as a group showed a significantly higher average myocardial T1 value relative to the reference group, with 3/5 male patients having an abnormally high myocardial T1 (above the 2SD limit of normal). Female IgG4-RD patients (n=6) had similar and normal myocardial T1 values to the reference group. ECV did not significantly differ between the two groups. IgG4-RD patients showed a significantly reduced global myocardial perfusion reserve (MPR), including two patients with a qualitative inducible perfusion defect. Only 3 out of the 11 IgG4-RD patients had a completely normal CMR. Conclusion Patients with IgG4-RD show frequent cardiac abnormalities as revealed by advanced CMR phenotyping. These include subclinical systolic dysfunction, ischaemic and non-ischaemic myocardial fibrosis, reduced myocardial perfusion reserve, and elevated myocardial T1 times. These abnormalities have been described in inflammatory cardiovascular diseases, supporting a plausible pathophysiological link with IgG4-RD. Future work in larger and multicentre cohorts is warranted, to systematically define the novel cardiovascular phenotype of IgG4-RD.Table 1Figure 1