Aneurysm: Complications

The following are the most important diseases or complications that may be contributed to by an aneurysm:

Cardiovascular system (I00-I99)

• Aortic dissection (synonym: aneurysm dissecans aortae) – acute splitting (dissection) of the wall layers of the aorta (main artery), with a tear of the inner layer of the vessel wall (intima) and hemorrhage between the intima and the muscular layer of the vessel wall (outer media), in the sense of aneurysm dissecans (pathological widening of the artery); may lead to the following disorders:
  • Acute renal failure (ANV).
  • Apoplexy (stroke)
  • Leg ischemia (reduced blood flow to the leg)
  • Hypotension
  • Mesenteric ischemia (reduced supply to the arteries supplying the intestine) or infarction (vascular occlusion).
  • Paraplegia due to spinal ischemia (reduced blood supply in the spine).
• Aortic valve insufficiency – defective closure of the aortic valve of the heart.
• Aneurysm rupture (rupture (tear) of aneurysm; free or covered) – risk depends on diameter and growth rate:
  • 1-2% for a diameter <5 cm
  • 20-40% for a diameter > 5 cm
  • Approximately one third of all brain aneurysm

  The mortality (mortality rate) of aneurysm rupture is circa 85%.

• Plaque embolization/embolism (partial or complete occlusion of a vessel by an embolus/entrained material).
• Right-sided heart failure (right-sided heart failure; due to penetration of an abdominal aortic aneurysm into neighboring organs; in this case: Inferior vena cava)
• Subarachnoid hemorrhage (SAB; hemorrhage between the spider meninges and the soft meninges; incidence: 1-3%); symptomatology: proceed according to “Ottawa rule for subarachnoid hemorrhage”:
  • Age ≥ 40 years
  • Meningismus (symptom of painful neck stiffness in irritation and disease of the meninges).
  • Syncope (brief loss of consciousness) or impaired consciousness (somnolence, sopor and coma).
  • Onset of cephalgia (headache) during physical activity.
  • Thunderclap headache/destructive headache (about 50% of cases).
  • Restricted mobility of the cervical spine (Cervical spine).
• Thrombosis (blockage of a vessel by a blood clot/thrombus).
• Hypovolemic shock (within a few seconds after free aneurysm rupture).

Further

• Approximately one-third of all patients with acute subarachnoid hemorrhage require long-term care.

Prognostic factors

• The risk of aneurysm rupture depends on the axial diameter of the aneurysm:
  • 4.0-4.9 cm: approx. 3%.
  • 5.0-5.9 cm: 10%
  • 6.0-6.9 cm: 15 %
  • 5.0-5.9 cm: 10%
  • 6.0-6.9 cm: 15 %
  • > 7 cm: 60
• Only one in four patients with an aneurysm died from the risks of the aneurysm (17% from rupture of the index aneurysm, 5% from rupture of another brain aneurysm or bleeding recurrence of a treated aneurysm, 2% from subarachnoid hemorrhage, SAB). The remaining 76% of patients died of cardio- and cerebrovascular disease (myocardial infarction (heart attack), apoplexy/stroke), as well as tumor and other diseases. Independent risk factors for death were:
  • Male sex
  • Excessive alcohol consumption (> 300 g alcohol/week)
  • Tobacco consumption

  Patients who did not smoke and drank little alcohol outlived the group of patients who smoked and drank by 10 to 20 years.

The major risk factors for aneurysm rupture listed below were generated from six prospective cohort studies involving nearly 8400 aneurysm patients:

• Ethnic origin (see below Origin).
• Blood pressure (hypertension)
• Age of patients
• Aneurysm diameter
• Previous cerebral hemorrhage due to aneurysms
• Aneurysm localization

Over the course of more than 29,000 person-years, 230 patients experienced aneurysm rupture, yielding a 1.4% one-year rate and a 3.4% five-year rate. From the risk factors presented, the researchers developed a risk score called PHASES (see Table 1). Based on the score obtained, a table shows the 5-year risk of rupture (see Tab. 2). Tab.1: PHASES score

Table 2: 5-year risk of rupture.