Treatment of Aneurysms
Aneurysms are defined as localized dilatations of a blood vessel wall and have been described since 2000 B.C. They generally develop slowly over time and are often only found incidentally. However, clinical symptoms can develop due to rupture, thrombosis, embolization, and compression of, or erosion into nearby structures. There is not a complete understanding of why aneurysms develop, but we do know that they can be clustered in families; up to 15% of patients with abdominal aortic aneurysms can have a first-degree relative with an aneurysm. Moreover, there is a clear association with tobacco smoking, more so than with either coronary artery disease or cerebrovascular disease. The basis for modern techniques of aneurysm repair was initially developed in the 1950s.
Less than 20 percent of aneurysms are found in the thoracic aorta, and more than two thirds of patients who are diagnosed with a thoracic aortic aneurysm will also have an abdominal aortic aneurysm. Open surgical repair of thoracic and thoracoabdominal aneurysms has been done since the 1950s. These long and complicated operations have more recently been replaced, in the appropriate patients, with endovascular techniques which have revolutionized the perioperative care and complication rate for these cases.
The abdominal aorta is the most common site for aneurysms, occurring 3 times more frequently than the thoracic aorta. However, up to 12 percent of these patients will also have thoracic aneurysms and approximately 3 percent will have lower extremity aneurysms. Abdominal aortic aneurysms concomitantly involve the iliac arteries in 25 percent. Aneurysms of the mesenteric and renal arteries are very rare. Rupture of any abdominal aneurysm is the most concerning potential complication. Perhaps the most famous aneurysm patient is Albert Einstein, who died of a ruptured aneurysm in 1955, six years after having aneurysm surgery. Ruptured abdominal aortic aneurysms are the 15th leading cause of death overall and the 10th leading cause of death in men older than age 55 years. Men over 55 with a family history of aneurysms or who have ever smoked should have a screening aortic duplex ultrasound. Similar to thoracic aortic aneurysm repairs, the surgical options for abdominal aneurysms include both open and endovascular approaches. For the majority of abdominal aneurysms nowadays, the first-line therapy involves a percutaneous, catheter-based repair.
While popliteal aneurysms constitute the majority of peripheral aneurysms, the common femoral artery is often the site of pseudoaneurysms and infected aneurysms. These peripheral aneurysms are more prone to thrombosis or embolization compared to abdominal or thoracic aneurysms. Unlike thoracic and aortic aneurysms, repair of these peripheral aneurysms still frequently requires open surgery.