Subclinical myocardial involvement in a cohort of patients with antisynthetase syndrome.

OBJECTIVES: There is an increasing interest in knowing whether patients with antisynthetase syndrome (ASSD) may have silent myocardial interstitial involvement. Mapping techniques in cardiac magnetic resonance (CMR) can detect subclinical myocardial involvement. The purpose of this study was to identify alterations in multiparametric CMR in ASSD patients without overt cardiac involvement. METHODS: Patients diagnosed with ASSD underwent a CMR along with the standard clinical workup, investigation of specific and associated myositis antibodies, and high-resolution chest CT. The CMR protocol includes routine morphologic, functional, and late gadolinium enhancement sequences in standard cardiac planes, as well as native T1 and T2 mapping sequences and extracellular volume (ECV) calculation. RESULTS: Twenty-five patients were included in this study (56% women; median age 56.3 years). Three patients were considered in the acute phase at the time of inclusion. Eight patients (32%) showed pathological findings in CMR (6 stable disease, 2 acute phase). Elevated T1, T2 and ECV mapping values were found in 20% (5/25), 17% (4/25) and 24% (6/25) of the group, respectively. Two patients in the acute phase had increased values of both T2 and ECV. CONCLUSIONS: Subclinical myocardial involvement in ASSD is not rare (32%) although its clinical significance is uncertain. Myocardial oedema (T2) was the most frequent finding, followed by increased T1 and/or ECV values likely signalling interstitial fibrosis. Of note, patients in the acute phase showed elevated T2 values.

Substrate characterization of the right ventricle in repaired tetralogy of Fallot using late enhancement cardiac magnetic resonance.

BACKGROUND: Three-dimensional (3D) substrate characterization by high-resolution late gadolinium enhancement cardiac magnetic resonance (LE-CMR) is useful for guiding ventricular tachycardia ablation of the left ventricle in ischemic heart disease. OBJECTIVE: The purpose of this study was to validate the substrate characterization and 3D reconstruction of LE-CMR images of the right ventricle (RV) in patients with repaired tetralogy of Fallot (rTOF) and to identify the algorithm that best fits with electroanatomic mapping (EAM). METHODS: RV LE-CMR images were compared with RV EAM in 10 patients with rTOF. RV LE-CMR images were postprocessed and analyzed to identify fibrotic tissue on 3D color maps. The 3D RV substrate reconstructions were created using an adjustable percentage of the maximum voxel signal intensity (MSI) of the scar region to define the threshold between core, transitional zone (TZ), and healthy tissue. Extensions of the core and TZ areas were compared with the scar (<0.5 mV) and low-voltage (0.5-1.5 mV) areas obtained by RV EAM. Agreement on anatomic isthmi identification was quantified. RESULTS: The best match between core and scar was obtained at 65% MSI cutoff (mean areas 17.4 ± 9.9 cm2 vs 16.9 ± 10.0 cm2, respectively; r = 0.954; P <.001). Agreement on anatomic isthmi identification was best at 60% MSI cutoff, which identified 95% of isthmi and achieved a total fit in 90% of patients. CONCLUSION: This study demonstrates that characterization of the RV substrate by postprocessing LE-CMR images in rTOF patients is feasible and validates the technique against RV EAM, which could help in planning target ablation.