A 56-year old male patient without cerebrovascular disease or risk factors presented with a painless, pulsatile right-sided cervical swelling. Ultrasonography showed a large aneurysm of the right common and internal carotid artery with homogeneous thickening of the vessel wall as well as a parietal thrombus and a dilation of the left common and internal carotid artery with markedly reduced blood flow velocities. In the enlarged lumen of the right internal carotid artery spontaneous echo contrast was apparent with slow, ineffective but orthograde blood flow motions. Ensuing diagnostic procedures revealed multiple aneurysms involving the aorta and its branches. Despite surgical removal of the aneurysm and glucocorticoid therapy, the patient died from a ruptured aneurysm of a coronary artery a few weeks later. Post-mortem examination showed panarteritis consistent with Takayasu's disease. Spontaneous echo contrast is a frequent echocardiographic finding in patients with atrial fibrillation and mitral stenosis, indicating decreased blood flow. This is associated with an increased risk of embolism. In our patient, spontaneous echo contrast indicated severely disturbed haemodynamics due to a large aneurysm of the carotid artery. In the rare case of multiple aneurysms, differential diagnosis should include dissections, infections, and connective tissue diseases. Takayasu's arteritis, however, should also be considered, which usually presents with stenoses, but may be associated with multiple aneurysms of the aorta or its branches. If the diagnostic criteria are present, immunosuppressive treatment should be initiated.