白袍恐懼症

Abdominal Aortic Aneurysm

1.Definition: aortic diameter at least one and one-half times (1.5x) the diameter

            measured at the level of the renal arteries

2.Sizes:

Normal - 2.0cm (range 1.4~3.0)

Aneurysmal - >3.0cm

Clinically significant - >4.0cm

3.Epidemiology - abdominal aorta is the most common site of arterial aneurysm

             - 最常見的位置是在 renal artery 跟 IMA 之間(95% infrarenal)

4.Risk Factors - >60 yrs 後發生率會隨著年齡而提升

             - smoking

             - male: female=3:1

             - atherosclerosis

             - HTN

             - family history

5.Clinical Manifestation – 75% asymptomatic

                   – 有症狀的 aneurysm 比較會 rupture

Ruptured Aneurysm - 通常有 severe abdominal, flank, or back pain

- hypotension, and

                 -50% pulsatile mass at or above the umbilicus

                 - survival rate is 25%

Inflammatory Aneurysm - abdominal or back pain, tenderness on palpation of

                      the abdomen, weight loss, and an elevated erythrocyte

                      sedimentation rate

6.Diagnosis – CT angiography (gold standard)

7.Management- the risk of aneurysm rupture correlates best with aneurysm size

(1)Medical Management- aneurysm diameter<5.5cm without risk factors for rupture can be followed using ultrasound or CT yearly.

-Doxycycline: MMP-inhibiting

(2)Surgical Management indication:

-symptomatic aneurysms of any size

-aneurysms diameter >5.5 cm

-increase in diameter>0.5 cm/year

-saccular aneurysms