An aneurysm consists of a weak part of a blood vessel that fills with blood and balloons out. Aneurysms that develop in the chest are called thoracic aortic aneurysm. In the abdomen, they are called abdominal aortic aneurysm and in the brain, cerebral aneurysm. The National Heart Lung and Blood Institute indicate that most aneurysms develop in the aorta, killing about 14,000 Americans per year. Prior to rupturing, aneurysms generally do not cause symptoms; however, many complications develop after rupturing.
Causes
Cerebral aneurysms have varying causes, the National Institute of Neurological Disorders and Stroke reports, including genetic diseases, such as certain circulatory disorders and "an inborn abnormality in an artery wall." Other causes, reports the same source, include blows to the head, high blood pressure, infection, tumors, fatty build-up in artery walls, smoking cigarette and drug abuse. Aortic aneurysms share some of the same causes, MayoClinic.com states, including cigarette use, high blood pressure and injury. Rarely, the aneurysm may be caused by an infection in the aorta that weakens the wall; this condition tends to run in families.
Unruptured Cerebral Aneurysms
Not all aneurysms will rupture, according to MayoClinic.com, and many never cause symptoms. However, as they grow, they may begin to produce pressure in the brain, chest or abdomen resulting in symptoms. Cerebral aneurysms may eventually grow large enough, the Aneurysm Foundation indicates, to press on regions of the brain or nerves coming out of the brain, causing neurological symptoms to develop. In unruptured cerebral aneurysms, MayoClinic.com identifies the following symptoms: pain above and behind the eye, dilated pupil, vision abnormalities, weakness, numbness or paralysis on one side of the face and drooping eyelid. The Aneurysm Foundation also identifies that the individual may experience problems with speech.
Unruptured Aortic Aneurysms
Aortic aneurysms grow at differing rates and may never grow large enough to cause symptoms, according to MayoClinic.com. The National Heart Lung and Blood Institute identifies that abdominal aortic aneurysms usually grow slowly over years. If they grow large enough some of the following symptoms may develop: a throbbing feeling in the abdomen, deep pain in the back or side of the abdomen and a steady, gnawing pain in the abdomen lasting for prolonged periods of time. MayoClinic.com identifies further symptoms, including "a pulsating feeling near the navel" and tenderness in the area as well. Thoracic aortic aneurysms act in the same manner as abdominal aneurysms, in that they do not cause symptoms unless they grow large enough. If this occurs, the National Heart Lung and Blood Institute indicate that the following symptoms may develop: pain in the neck, jaw, back or chest and "coughing, hoarseness or trouble breathing or swallowing."
Ruptured Cerebral Aneurysms
A ruptured cerebral aneurysm may result in a subarachnoid hemorrhage, producing sudden symptoms, according to the Aneurysm Foundation. The National Institute of Neurological Disorders and Stroke identify that the individual may experience extreme headache, a loss of consciousness, nausea, vomiting and double vision. Additionally, the burst aneurysm may cause a seizure, prolonged coma, changes in mental status and sensitivity to light. This source warns that individuals experiencing their worst headache ever should seek immediate medical care. In some cases of cerebral aneurysm, the individual may experience what the National Institute of Neurological Disorders and Stroke call "sentinel" headaches, which results from an aneurysm leaking blood. This may occur days to weeks prior to a rupture.
Ruptured Aortic Aneurysms
When an aortic aneurysms ruptures, whether thoracic or abdominal, sudden symptoms may develop. According to the National Heart Lung and Blood Institute these symptoms include severe and sudden pain in the back and abdomen, nausea, vomiting, rapid heart rate when standing and clammy, sweaty skin. Internal bleeding caused by a ruptured aneurysm may cause shock, a dangerous condition where not enough blood flow reaches the body's organs. If any of these symptoms are left untreated, the National Heart Lung and Blood foundation warns that organ damage or death may occur.
