心臟病及保健 Heart Disease And Health http://心臟病.tw www.heartdisease.idv.tw
DISEASES OF AORTA
Andrew Ying-Siu Lee, MD,PhD.
(1) AORTIC ANEURYSM:-
Common causes are : (1) atherosclerosis, leading to vessel wall weakness forming aneurysms, (2) cystic medial
necrosis, leading to decreased elasticity and tortuosity of vessel wall forming aneurysms, (3) syphilis and other infections,
causing occlusive arteritis known as endarteritis obliterans, (4) trauma, (5) risk factors such as hypertension, smoking,
diabetes mellutis, hyperlipidemia, genetics etc.
Majority is asymptomatic (40%), but rupture of aortic aneurysm may be the first fatal presentation. Abdominal
aortic aneurysm may cause hypogastric or low back pain due to lumbar compression. Thoracic aortic aneurysm may
likewise cause chest or back pain. Aortic aneurysm may also cause pneumonia, stridor (tracheal compression), dysphagia
(esophageal compression), hoarseness of voice (compression of recurrent laryngeal nerve) etc. Thoracic aortic aneurysm
may cause aortic insufficiency and hence heart failure and myocardial ischemia. Thrombi formation in the aortic aneurysm
may embolize systematically causing stroke, limb ischemia and gangrene etc.
For abdominal aortic aneurysm, a pulsatile mass with bruit may be observed. Thoracic aortic aneurysms seldom have
abnormal signs. Diagnosis include X-ray, ultrasound, computerized tomography, magnetic resonance imaging, angiography.
Therapy of aortic aneurysms is mainly surgical. If the aortic aneurysm is greater than 6 cm in diameter, or complicated
with aortic insufficiency or obvious symptoms, percutaneous endovascular stent-graft or surgical operation are required.
Medical treatment include antihypertensive drugs, stop smoking, control hyperlipidemia etc.
(2) AORTIC DISSECTION:-
Etiology similar to that of aortic aneurysm, causing medial rupture and hence dissection of vessel wall forming
pseudo vessel lumen.
Symptoms include: sudden onset of severe chest pain, abdominal pain or back pain, tearing and stabbing in character,
migratory in quality. It may also lead to myocardial infarction, stroke, mesenteric ischemia, renal failure, limb ischemia etc.
Occasionally aortic dissection and rupture may lead to cardiac tamponade and cardiogenic shock.
Majority has very high blood pressure (80-90%), associated with pulse deficit, heart murmur and neurological
abnormality. Diagnosis include : electrocardiogram, chest X-ray, ultrasound, computerized tomography, magnetic
resonance imaging, aortography etc.
Patients with ascending aortic dissection usually die within several days without surgical intervention. Patients with
descending aortic dissection may be treated with antihypertensive drugs. Surgical intervention is needed if pain persists
or dissection enlarged.
(3) AORTOARTERITIS SYNDROMES :-
Due to syphilis or other infections, autoimmune diseases , causing inflammation of aorta and branches.
Nonspecific aortoarteritis include Takayasa’s arteritis, Reiter syndrome, gaint cell arteritis etc.
Symptoms include: fever, poor appetite, weakness, cold sweating, chest discomfort, joint pain. Aortoarteritis
syndromes may also lead to vessel occlusion causing stroke, limb ischemia, myocardial ischemia, heart failure etc.