Pseudoaneurysm after ICD battery replacement

False aneurysms of the extracranial carotid arteries are rare and mainly of traumatic origin. We report on a patient who presented with a sudden onset mass in his right neck 2 weeks after routine replacement of his ICD battery. He had received systemic anticoagulation since an aortic valve replacement 5 years before. By color Doppler sonography the mass was identified as a partly thrombosed false aneurysm originating from the common carotid artery. As no spontaneous resolution occurred during the following days the aneurysm was removed surgically 5 days later without further complications. However no connection to the common carotid artery was found at surgery. Yet in the histopathological examination the specimen showed the morphological characteristics of a pseudoaneurysm. There was no history of neck-trauma and no attempted vascular access during the recent operation.