Assessment of cardiac abnormalities in Duchenne's muscular dystrophy by (99m)Tc-MIBI gated myocardial perfusion imaging.

Cardiac abnormalities in Duchenne's muscular dystrophy (DMD) are often detected in adult patients and their early detection is warranted. Studies have suggested that myocardial damage may be detected by cardiovascular magnetic resonance imaging or by echocardiography at the early stage of DMD. We aimed to identify early changes of cardiac abnormalities in children with DMD by technetium 99m-methoxyisobutylisonitrile ((99m)Tc-MIBI) gated myocardial perfusion imaging (GMPI). Forty-three boys aged 3 to 14 years (mean age 8.2±3.6 years) with DMD and 12 age-matched normal boys as control were studied by G-MPI. These patients were at early stage according to previous studies on DMD. Uptake of (99m)Tc-MIBI in 7 regional walls and 17 segments of the left ventricle were visually analyzed. Quantitative gated single photon emission tomography (QGSSPET) analysis of myocardium was performed to evaluate left ventricular function (LVEF). Gated myocardial perfusion imaging revealed cardiac abnormalities in 81.4% of all patients. Regional perfusion decrease involving multiple walls of LV was present. Four of the patients demonstrated mild abnormalities (11.4%), 7 moderate (20.0%) and 24 severe abnormalities (68.6%). Evident LV ejection fraction (EF) decrease (42.1±6.4%) and dilation with globally poor perfusion were found in three patients, aged 10 to 14, which had significant difference compared with the control group (EF=58.4±4.7%, P=0.001). The rest cases, aged 3 to 9 years, had normal LVF. In conclusion, from the 35 cases of DMD patients (aged 3 to 14 years), regional myocardial perfusion decrease was detected in multiple walls by (99m)Tc-MIBI G-MPI at an early stage, while left ventricular function decrease (3/35, 8.6%) appeared late at about 10 years of age or older as compared with the control group in this study.