Cardiovascular magnetic resonance imaging in asymptomatic patients with connective tissue disease and recent onset left bundle branch block.

Background-aim: Recent LBBB in connective tissue diseases (CTDs) is challenging, due to high incidence of underlying pathology that may remain undetected, due to limitations of imaging tests. We hypothesized that cardiovascular magnetic resonance (CMR) may be of diagnostic value in CTDs with recent LBBB and normal echocardiogram.

Patients-methods: 26 CTDs, aged 32 ± 7 yrs (19 F) and 26 controls without CTDs, aged 60 ± 4 yrs (10 F) with recent LBBB and normal echo were evaluated by CMR. The CTDs included 6 sarcoidosis (SRC), 4 systemic sclerosis (SSc), 6 systemic lupus erythematosus (SLE), 6 rheumatoid arthritis (RA) and 4 inflammatory myopathies (IM). CMR was performed by 1.5T. LVEF, T2 ratio (oedema imaging) and late gadolinium enhancement (LGE) (fibrosis imaging) were evaluated. Acute and chronic lesions were characterised by T2>2 and positive LGE and T2<2 and positive LGE, respectively. According to LGE, lesions were characterised as diffuse subendo-, subepicardial/intramural not following and subendocardial/transmural following the distribution of coronaries, indicative of vasculitis, myocarditis and myocardial infarction, respectively.

Results: CTDs were younger (p<0.001), with higher incidence of abnormal CMR (42.31 vs 30.77%, p=NS), including dilated cardiomyopathy (11.54%), diffuse subendocardial fibrosis (11.54%), myocardial infarction (7.69%) and acute myocarditis (11.54%) vs dilated cardiomyopathy (19.23%), myocardial infarction (7.69%) and acute myocarditis (3.85%), detected in non-CTDs.

Conclusions: In CTDs with recent LBBB, CMR documented acute and chronic cardiac pathology, particularly myocarditis. CMR should be considered as an adjunct to conventional diagnostic workup in both patient groups, more so in CTDs.