A 54-year-old Caucasian male with a history of IE complicated by cerebrovascular accident 15 years prior presented to the emergency department complaining of slurred speech for the past two days. He reported that his lower mouth felt as though it had been “numbed by a dentist,” resulting in subjective dysarthria. At the time of presentation, he denied headaches, visual changes, nausea, vomiting, or numbness or weakness in the extremities.
The patient was febrile at 102.3 degrees Fahrenheit, and his cardiovascular exam revealed a 3/6 holosystolic murmur most prominent at the left midclavicular line with radiation to the axilla. The neurologic exam was significant for left facial weakness, subtle slurring of speech, and diffuse hyperreflexia of all four extremities. Marked clubbing of his fingers on both hands was appreciated.
The head CT showed an old left posterior cerebral artery infarct and prominent basal ganglia calcification, but neither active bleeding nor acute infarction. The MRI was significant for a small acute nonhemorrhagic infarct in the right frontal periventricular white matter as well as scattered punctate areas of chronic blood products (). The echocardiogram visualized large mobile vegetations on the mitral valve (). 6 of 6 blood cultures were positive for Streptococcus viridans. Intravenous Penicillin G and Gentamicin were started immediately, and after 5 days of antibiotic treatment, the patient's dysarthria and left facial weakness improved.
Figure 1 MRI of brain on presentation: (a) sagital view showing acute right side frontal lobe infarct marked by arrow. (b) Axial view with same right side frontal lobe infarct marked by arrow. (c) Diffusion-Weighted Image of ischemic stroke in the right centrum (more ...)
Four chamber view echocardiogram showing large vegetation on the MVL marked by arrow. LV-left ventricle, LA-left atrium, RV-right ventricle, RA-right atrium, TV-tricuspid valve, MVL-mitral valve leaflet.
Six days into antibiotic therapy, the patient complained of a severe headache and was noticeably slow to respond. The slurred speech and left facial weakness also returned. A noncontrast CT head was repeated and showed acute subarachnoid hemorrhage (). The patient's condition deteriorated; he became obtunded and required endotracheal intubation and mechanical ventilation.
Figure 3 Progression of the ruptured Mycotic Aneurysm: (a) initial subarachnoid hemorrhage after 6 days IV antibiotics. Note interhemispheric hemorrhage. (b) Repeat noncontrast CT Brain 12 hours later, intraparenchymal hemorrhage is marked by arrow. Note prominent (more ...)
The subsequent CT Cerebral Angiogram established a multilobulated cerebral aneurysm at the A3 segment of the right distal anterior cerebral artery measuring 13
mm by 8.7
mm at the coronal plane, as well as interval development of intraventricular and intraparenchymal hemorrhage (). After the placement of a ventriculostomy catheter, the patient was emergently taken to the operating room to undergo aneurysm clipping and ligation. The aneurysm was located during dissection of the falx interhemispheric fissure. As is typical of a mycotic aneurysm, it was of poor consistency with degenerated and friable walls. The operation was complicated by aneurysm rupture for which hemostasis was achieved with microcottonoids and clipping. During the recovery period the patient was eventually able to follow basic commands, though the extent of his intracranial and valvular disease was severe. He ultimately required a tracheostomy, and percutaneous gastric tube. Because of the presence of intracranial hemorrhage and acute infarct, replacement of his mitral and aortic valves was deferred. The patient was transferred to a long-term nursing facility and given followup with the cardiothoracic surgery team for reassessment after a 6 week course of IV antibiotics.
Figure 4 CT Cerebral angiogram showing a large fusiform aneurysm at the distal anterior cerebral artery (ACA). (a) Shaded Surface Display CT coronal view showing a large fusiform aneurysm at the distal segment of the ACA marked by the large arrow. Proximal ACA (more ...)