Aneurysm

An aneurysm refers to a circumscribed pathologic (abnormal) bulge in the arterial wall. Lesser bulges are referred to as ectasia. Aneurysms can occur in any artery in the body. The following forms of aneurysm can be distinguished:

• Aneurysm arteriovenosum (aneurysm varicosum) – connection between a vein and an artery, which is accompanied by dilatation of the venous portion.
• Aneurysm cordis (aneurysm of the heart wall).
• Aneurysm dissecans – fissure formation of the arterial wall originating from a tear in the intima (inner layer of the vessel); this results in the formation of a false channel, which can lead to acute bleeding via the outer wall of the artery
• Aneurysm fusiforme – aneurysm, which is noticeable by a spindle-shaped bulge.
• Aneurysm poststenoticum – outpouching of the arterial wall, which is located behind a stenosis (narrowing); the cause is the increased wall pressure.
• Aneurysm sacciforme – aneurysm, which is characterized by a sac shape and a narrow neck.
• Aneurysm venosum – rarely occurring dilation of veins.
• True aneurysm (aneurysm verum) – aneurysm characterized by localized dilatation of all wall layers.
• Embolic (mycotic) aneurysm – infectious outgrowth occurring mainly in endocarditis (inflammation of the inner wall of the heart).
• False aneurysm (aneurysm spurium) – refers to a hematoma (bruise) located on the arterial wall, which is associated with a tear in the arterial wall

According to the localization, the following significant forms can be distinguished:

• ICD-10-GM I67.9: Cerebrovascular disease, unspecified.
• ICD-10-GM I71.-: Aortic aneurysm and dissection.
  • ICD-10-GM I71.1: Aneurysm of the thoracic aorta, ruptured
  • ICD-10-GM I71.2: Aneurysm of thoracic aorta, without indication of rupture – wall bulge of aorta (main artery) to > 3.5 cm in diameter
  • ICD-10-GM I71.3: Aneurysm of the abdominal aorta (AAA), ruptured.
  • ICD-10-GM I71.4: Abdominal aortic aneurysm (AAA), without indication of rupture – bulging of the arterial wall of the infrarenal or suprarenal aorta by > 30 mm, corresponding to 150% of the “normal” vessel diameter; with more than 90% predominant proportion of aortic aneurysms [see below Abdominal aortic aneurysm (BAA); synonym. Abdominal Aortic Aneurysm (AAA)]
  • ICD-10-GM I71.5: Aortic aneurysm, thoracoabdominal, ruptured.
  • ICD-10-GM I71.6: Aortic aneurysm, thoracoabdominal, without indication of rupture.
• ICD-10-GM I72.-: Other aneurysm and other dissection.
  • ICD-10-GM I72.0: Aneurysm and dissection of the carotid artery
  • ICD-10-GM I72.3: Aneurysm and dissection of the iliac artery

Aortic dissection is differentiated on the basis of the time course from the initial event (usually thoracic pain event) into:

1. Acute aortic dissection: presentation of the patient within the first 2 weeks after symptom onset or initial diagnosis.
2. Subacute phase of aortic dissection: period of 2-6 weeks after symptom onset.
3. Chronic phase of aortic dissection: after 6 weeks or according to the European Society of Cardiology guidelines [see guidelines below] if the patient has survived more than 90 days after the acute event.

Sex ratio: aneurysm of the vessels supplying the brain: women are affected slightly more often than men. Thoracic aortic aneurysm: males to females is 2-4: 1.Abdominal aortic aneurysm: males to females is 5-6: 1.Frequency peak: the maximum incidence of thoracic aortic aneurysm is in the 6th and 7th decade of life.Abdominal aortic aneuysm occurs in smokers and in patients with hypertension (high blood pressure), hyperlipidemia (dyslipidemia) and diabetes mellitus well before the age of 65. Abdominal aortic aneurysm affects up to 10% of male hypertensive patients over 70 years of age. The prevalence (disease frequency) of aneurysms of the brain-supplying arteries is 2-3 % (in Germany). The frequency increases with age.The incidence (frequency of new cases) of great vessel aneurysm is approximately 40 cases per 100,000 population per year. The incidence of thoracic aortic aneurysm is approximately 5-10 diseases per 100,000 population per year. Course and prognosis: Prognosis depends on the location, size, and growth rate of the aneurysm. With an abdominal aortic aneurysm > 5 cm (men) or > 4.5 cm (women), the risk of rupture increases from 3% to 5% within the following year. The lethality (mortality based on the total number of people with the disease) of ruptured abdominal aortic aneurysm is circa 60-80%.