Cardiovascular magnetic resonance detects subclinical cardiac involvement in giant cell arteritis

To assess cardiac involvement in patients with newly diagnosed giant cell arteritis (GCA) using cardiovascular magnetic resonance (CMR).

In this prospective single-center study, patients with newly diagnosed GCA underwent CMR at baseline and under therapy 6 months later. The imaging protocol enabled evaluation of cardiac function and volumes, edema, late gadolinium enhancement (LGE), and T1 and T2 mapping, including extracellular volume fraction (ECV). Healthy controls were included for comparison. Group comparisons were performed using t-tests, Mann-Whitney U, and chi-square tests. Paired t-tests assessed longitudinal changes.

A total of 45 GCA patients (mean age 73±9 years; 42.2% female) and 30 healthy controls were included. Active inflammatory cardiac disease was found in 3/45 (6.7%) of patients, comprising active pericarditis in 2/3 (66.7%) and active myocarditis in 1/3 (33.3%). LGE was observed in 12/45 (26.7%) of patients (5/12 [41.7%] with ischemic, 5/12 [41.7%] with non-ischemic, and 2/12 [16.7%] with pericardial pattern). Compared to controls, GCA patients had significantly elevated native T1 relaxation times (987±29 vs. 968±22 ms; p=0.003) and ECV values (27.3±3.8% vs. 25±2.1%; p=0.003). Patients with large-vessel involvement (24/45 [53.3%]) showed higher myocardial ECV values (28.7±4.2% vs. 25.8±2.5%, p=0.008). Follow-up CMR was performed in 35 patients; here, no significant changes were observed compared to baseline CMR (e.g., native T1: 984±25 vs. 980±20 ms, p=0.397).

In patients with newly diagnosed GCA, CMR reveals subclinical cardiac involvement, including active inflammatory disease (myocarditis and pericarditis), post-ischemic scars, and signs of non-ischemic myocardial fibrosis.