Evaluation of myocardial damage in Duchenne's muscular dystrophy with thallium-201 myocardial SPECT.

Myocardial damage and cardiopulmonary functions in patients with Duchenne's muscular dystrophy (DMD) were assessed using thallium-201 myocardial single-photon emission computed tomography (SPECT) and technetium-99m multigated radionuclide angiography. Twenty-five patients with DMD were divided into 4 groups according to percent of perfusion defect (%PD) calculated by the bull's-eye method and age. PD was detected in 24 (96.0%) of 25 patients with DMD, and it spread from the left ventricular lateral wall to the anterior wall and/or interventricular septum. PD was detected even in a 6-year-old DMD boy. Patients in Group I (%PD > or = 10 and age < 15 years old) were shown to have a higher risk of left-sided heart failure without respiratory failure. Patients in Group II (%PD > or = 10 and age > or = 15) showed decreased pulmonary function and worsened arterial blood gas values as compared with Group IV (%PD < 10 and age > or = 15). There was no significant difference in cardiac function among the 4 groups. It is postulated that myocardial damage in Group II patients is dependent primarily on a deficiency of dystrophin and on chronic respiratory failure, and that some of them are at risk of cardiopulmonary failure. It is concluded that myocardial SPECT is useful for the early diagnosis of myocardial damage and evaluation of cardiopulmonary function in DMD patients.