Standard and feature tracking magnetic resonance evidence of myocardial involvement in Churg–Strauss syndrome and granulomatosis with polyangiitis (Wegener’s) in patients with normal electrocardiograms and transthoracic echocardiography

The aim of the study was to evaluate the presence and spectrum of cardiac abnormalities identified by cardiac magnetic resonance (CMR) in subjects in clinical remission of Churg–Strauss syndrome (CSS) and granulomatosis with polyangiitis (Wegener’s) (WG) with normal ECG and transthoracic echocardiography (TTE). Eleven (7 females, 4 males, mean age 42.4 ± 9.6 years) CSS and 10 (4 females, 6 males, mean age 45.3 ± 10.9 years) WG patients in clinical remission with normal ECG and TTE underwent CMR. Segmental peak-systolic myocardial strain (ε_ps) was measured using feature tracking cine-sequence based technique. Left ventricular (LV) ejection fraction, end-diastolic volume and myocardial mass indexes were 66.2 ± 5.8 %, 66.1 ± 6.6 ml/m², and 61.0 ± 8.9 g/m², respectively. No patient showed regional wall motion abnormalities and signs of myocarditis. Nine CSS and 8 WG patients demonstrated decreased segmental longitudinal, circumferential or radial ε_ps and myocardial late gadolinium enhancement (LGE) (6 subendocardial, 10 midwall, 8 subepicardial) areas. In CSS and WG subjects with LVLGE lesions the mean LVLGE extent was 2.0 ± 1.6 % and 2.3 ± 1.5 % (p = 0.65), respectively. Segmental ε_ps was decreased longitudinally (−11.8 ± 5.6 %) for subendocardial LGE, radially (13.7 ± 8.7 %) for subepicardial LGE, and circumferentially (−16.6 ± 4.2 %), longitudinally (−13.2 ± 5.5 %) and radially (18.8 ± 8.1 %) for midwall LGE, if compared to longitudinal (−22.7 ± 5.1 %), circumferential (−23.6 ± 5.6 %) and radial (34.2 ± 15.7 %) ε_ps in controls (11 females, 10 males, mean age 43.9 ± 10.5 years) (all p < 0.01). Despite clinical remission, normal ECG and TTE, most CSS and WG patients demonstrate decreased segmental ε_ps and non-ischemic LGE lesions without signs of myocarditis.