Benjamin Marty1,2, Raymond Gilles3, Marcel Toussaint1,2, Anthony Béhin4, Tanya Stojkovic4, Bruno Eymard4, Pierre G Carlier1,2, Karim Wahbi4. 1. NMR Laboratory, Neuromuscular Investigation Center, Institute of Myology, Bâtiment Babinski, Groupe Hospitalier Pitié-Salpêtrière, 47-83 boulevard Vincent Auriol, Paris, France. 2. NMR Laboratory, CEA/DRF/IBFJ/MIRCen, Groupe Hospitalier Pitié-Salpêtrière, 47-83 Boulevard Vincent Auriol, Paris, France. 3. Cardiology Department, CHWAPI, Site Union, 51 rue des Sports, 7500 Tournai, Belgium. 4. Centre de Référence de Pathologie Neuromusculaire Nord/Est/Ile-de-France, Institute of Myology, Assistance Publique des Hôpitaux de Paris, Groupe Hospitalier Pitié-Salpêtrière, 47-83 Boulevard Vincent Auriol, Paris, France.
Abstract
AIMS: Becker muscular dystrophy (BMD) is a genetic neuromuscular disease characterized by an alteration of the dystrophin protein. Myocardial involvement is frequent, eventually progressing to a dilated cardiomyopathy, and represents the most common cause of death for this pathology. We performed a comprehensive evaluation of myocardial functional and structural alterations encountered in a large cohort of BMD patients using quantitative cardiac magnetic resonance (CMR) imaging. METHODS AND RESULTS: Eighty-eight BMD patients and 26 age-matched volunteers underwent standard cine and tag imaging to assess myocardial function and dyssynchrony, while native T1, T2, and extracellular volume fraction (ECV) were measured for tissue characterization. The left ventricular ejection fraction (LV-EF) was significantly reduced in 26% of the BMD patients. Patients exhibited higher dyssynchrony index than controls (6.94 ± 3.17 vs. 5.09 ± 1.25, P = 0.005). Diastolic dyssynchrony also exists in patients where systolic function was normal. BMD subjects, compared with controls, had significantly higher native T1, T2, and ECV (1183 ± 60 ms vs. 1164 ± 22 ms, 47.5 ± 4.5 ms vs. 45.6 ± 3.4 ms, 0.282 ± 0.050 vs. 0.231 ± 0.027, respectively, P < 0.05). Native T1, T2, and ECV correlated with LV-EF (R = -0.79, -0.70, and -0.71, respectively, P < 0.001) and N-terminal-pro brain natriuretic peptide (R = 0.51, 0.58, and 0.44, respectively, P < 0.001). CONCLUSION: Quantitative CMR represents a powerful tool to evaluate structural and functional impairments in the myocardium of BMD subjects. Native T1, T2, and ECV provided quantitative biomarkers related to inflammation and fibrosis, and could stratify disease severity. Published on behalf of the European Society of Cardiology. All rights reserved.
AIMS: Becker muscular dystrophy (BMD) is a genetic neuromuscular disease characterized by an alteration of the dystrophin protein. Myocardial involvement is frequent, eventually progressing to a dilated cardiomyopathy, and represents the most common cause of death for this pathology. We performed a comprehensive evaluation of myocardial functional and structural alterations encountered in a large cohort of BMDpatients using quantitative cardiac magnetic resonance (CMR) imaging. METHODS AND RESULTS: Eighty-eight BMDpatients and 26 age-matched volunteers underwent standard cine and tag imaging to assess myocardial function and dyssynchrony, while native T1, T2, and extracellular volume fraction (ECV) were measured for tissue characterization. The left ventricular ejection fraction (LV-EF) was significantly reduced in 26% of the BMDpatients. Patients exhibited higher dyssynchrony index than controls (6.94 ± 3.17 vs. 5.09 ± 1.25, P = 0.005). Diastolic dyssynchrony also exists in patients where systolic function was normal. BMD subjects, compared with controls, had significantly higher native T1, T2, and ECV (1183 ± 60 ms vs. 1164 ± 22 ms, 47.5 ± 4.5 ms vs. 45.6 ± 3.4 ms, 0.282 ± 0.050 vs. 0.231 ± 0.027, respectively, P < 0.05). Native T1, T2, and ECV correlated with LV-EF (R = -0.79, -0.70, and -0.71, respectively, P < 0.001) and N-terminal-pro brain natriuretic peptide (R = 0.51, 0.58, and 0.44, respectively, P < 0.001). CONCLUSION: Quantitative CMR represents a powerful tool to evaluate structural and functional impairments in the myocardium of BMD subjects. Native T1, T2, and ECV provided quantitative biomarkers related to inflammation and fibrosis, and could stratify disease severity. Published on behalf of the European Society of Cardiology. All rights reserved.