Global Myocardial Edema in Antisynthetase Syndrome Detected by Cardiovascular Magnetic Resonance Mapping Techniques
A 56-year-old man presented with 7 months of fever, breathlessness, cough, and proximal muscle weakness with tenderness. His medical history was hypertension. His examination was unremarkable except for peripheral edema and a new, scaly, fissured erythematous rash on the hands and fingers (Figure 1). Blood tests revealed normocytic anemia, low total protein, raised inflammatory markers (C-reactive protein, 59 mg/L [normal, 0–5 mg/L]; erythrocyte sedimentation rate, 43 mm/h [normal, 1–20 mm/h]), and negative infective screen. The ECG was normal. Chest radiography and subsequent computed tomography showed interstitial lung disease. Echocardiography was normal (Movie IA in the online-only Data Supplement), but N-terminal pro-brain natriuretic peptide was very elevated at 245 pmol/L (normal, <47 pmol/L; high, >236 pmol/L).
Conventional cardiovascular magnetic resonance (CMR) showed a small pericardial effusion but normal cardiac size and function (Movie IIA in the online-only Data Supplement). There was no edema or focal fibrosis on T2-weighted imaging and late gadolinium enhancement, respectively. However, with the use of novel CMR parametric mapping techniques to assess T1, T2, and the extracellular volume, abnormalities were found: elevated native myocardial T1 (1090 milliseconds; normal, 968±32 milliseconds; Figure 2A) using a shortened modified look locker inversion recovery sequence, elevated T2 (62 milliseconds; normal, 52±3 milliseconds; Figure 2B) using T2 mapping, and increased extracellular volume at 15 minutes after contrast administration (0.40; normal, 0.25±0.04), values obtained from averaging all 6 segments on a mid short-axis slice, suggesting global myocardial edema. Rheumatology review raised the clinical suspicion of antisynthetase syndrome, confirmed by a positive anti-PL12 antibody. A right ventricular biopsy showed a mild interstitial cellular infiltrate, no vasculitis, no granulomas, and no fibrosis. The patient was treated with oral steroid therapy with dramatic clinical improvement. His CMR was repeated 2 months later, and all mapping parameters had returned to normal (T1=994 milliseconds, T2=53 milliseconds, extracellular volume=0.29; Figure 2C and 2D and Movie IIB in the online-only Data Supplement), with a decrease in N-terminal pro-brain natriuretic peptide to nearly normal at 53 pmol/L and normalization of inflammatory markers (C-reactive protein, 2 mg/L; erythrocyte sedimentation rate, 7 mm/h).
Antisynthetase syndrome is a rare autoimmune disease in which antibodies are generated to the machinery of protein synthesis. Autoantibodies to aminoacyl-transfer RNA synthetases (antisynthetase antibodies) are implicated in the pathogenesis and correlate with disease activity.1 Multisystem involvement includes interstitial lung disease, myositis, arthropathy, fever, Raynaud phenomenon, and skin (“mechanic’s hands,” as seen in this patient; Figure 1). Cardiac involvement has previously been described only in the right ventricle of 1 patient.2 The disease can be treated, as here, by immunosuppression.
CMR has become the gold standard method for the evaluation of myocardial edema, but conventional CMR can miss diffuse, global disease. Here, mapping techniques permitted the detection of previously undefined cardiac involvement, manifesting as global myocardial edema, providing new insights into the disease and potential methods for diagnosis and monitoring therapy in clinical practice. Developments in CMR imaging techniques are enabling rapid, clinically feasible parametric mapping,3,4 as in this case.
The online-only Data Supplement is available with this article at http://circ.ahajournals.org/lookup/suppl/doi:10.1161/CIRCULATIONAHA.115.017430/-/DC1.
- © 2016 American Heart Association, Inc.
- Moon JC,
- Messroghli DR,
- Kellman P,
- Piechnik SK,
- Robson MD,
- Ugander M,
- Gatehouse PD,
- Arai AE,
- Friedrich MG,
- Neubauer S,
- Schulz-Menger J,
- Schelbert EB