Natural
history[1] of vascular aneurysm
Thoracic Aneurysm
§ If aortic dissection is excluded, the vast majority of cases have been examples of atherosclerotic aneurysm, and these predominantly involve the descending aortic segment
- Recent
studies suggest that the 5 year mortality rate may approach 75%
- 33 —
50% of deaths result from rupture of the aneurysm
- Location
of aneurysm did not affect mortality rate, but advanced age, and aneurysm
more than 6 cm in size, the presence of hypertension, cerebrovascular
disease and the association of other cardiovascular disease all increased
the risk of death
- Outlook
for patients with ascending aortic aneurysm attributable to medial
degeneration is very grim; in one series 52 of 56 patients with Marfan’s
died as a consequence of aortic disease
- The
surgical mortality rate for all aneurysms of the ascending or descending
aorta is about 15%; however it is higher for those affecting the
transverse arch and origins of the brachiocephalic arteries
- Long
term survival is good; deaths during this period are usually due to
associated diseases [although aneurysms occasionally develop in other
parts of the aorta]
Abdominal Aneurysm
- The
chance of dying from rupture are 1 in 3
- Chance
of dying from rupture is greater if aneurysm exceeds 6 cm in diameter
- Mortality
rate for operative repair is less than 5%
Aortic Dissection
- Without
medical or surgical intervention mortality post aortic dissection:
- Hypotension
usually indicates aortic rupture with a very serious immediate prognosis
[almost 100% mortality in untreated patients]— almost all such patients
have a proximal dissection. They constitute 25% of those patients with
involvement of ascending aorta
§ Have a more favourable survival rate for descending aorta dissection — 50% mortality in first 2 weeks
- Almost
50% of all survivors die within 3 months; Those who survive for longer
than a year may expect reasonable longevity.
- Late
deaths may be due to cerebrovascular complications of hypertension, heart
failure from severe AR or rupture of a saccular aneurysm complicating the
dissection
- Surgical
mortality [short term]
- Type I 15%
- Type
II 5%
- Type
III 12%
- Surgical
mortality [10 years]
- Overall35%
- Type
II > 50%