We report the case of a 12-year-old girl who presented with heart failure symptoms that were treated as dilated cardiomyopathy. The echocardiogram showed a dilated left ventricle, poor ejection fraction, and long segment narrowing of the descending thoracic aorta. A cardiac CT further supported this finding; hence, the diagnosis of Takayasu's arteritis was proposed. The cardiac MRI revealed a non-ischemic pattern in delayed gadolinium enhancement at the lateral left ventricular wall. She was given steroidal therapy due to vasculitis but was later referred for stenting of the stenosed descending thoracic aorta.