An aneurysm is a permanent, localized, abnormal dilation of a blood vesselOccurring due to congenital or acquired weakening or destruction of thevessel wall.Most commonly aneurysm involvelarge elastic arteries.It causes serious ill effects like1). Thrombosis and Thromboembolism.2). Alteration in the flow of blood.3). Rupture of the vessel resulting in sever fatal haemorrhages.4). Compression of neighbouring structures.
Aneurysms are classified by three ways i.e1).Depending upon the composition of wall.2).Depending upon the shape.3).Depending upon pathogenic mechanisms
Depending upon composition of vessel wall there are 2 types of aneurysm i.e1). True aneurysm when all the 3 normal layers of the blood vessel are involved.2). False aneurysm When only fibrous layer of the wall is involved and the rest of the layers are damaged due to trauma.
There are 5 types i.e1).spherical having spherical outpouching.2).Fusiform having spindle shape dilatation.3).Cylindrical having continuous parallel dilatation.3).varicose having tortuous dilation of the vessel.4).Racemose having mass of intercommunicating small arteries and veins.
Aneurysms can occur when the the structure and function of the connective tissue within vascular wall is compromised, and it occurs in the following conditions i.e. 1)Marfan syndrome. 2)Loeys_Dietz syndrome. 3)Ehler_Danlos syndrome. 4) Vitamin C deficiency 5)Increased MMP production by macrophages in vasculitis. 6)Ischemia of the media by athersclerotic thickness of the intima and systemic hypertension. 7)Direct trauma to the vessel.
• More common in men• Frequency increases after 50 years of age.• Most common in abdominal aorta especially infrarenal , and other sites include thoracic aorta, iliac arteries,• Clinical features include,• 1.rupture• 2.Obstruction• 3.Embolism• 4.Abdominal mass
Syphilitic aneurysm occurs usually in tertiary stage of syphilis.• More common in men after the age of 50 years.• The predominant site of involvement is thoracic aorta.• Pathogenesis; Inflammatory infiltrate around the vasa vasorum endarteritis obliterans destruction of smooth muscle and elastic tissueOf media weakening of vessel wall formation of aneurysm
1. Respiratory difficulties.2. Difficulty in swallowing3. Persistent cough due to pressure on recurrent laryngeal nerve.4. Pain caused by erosion of vertebral bodies.5. Cardiac disease6. RuptureUsually death occurs due to cardiac diseases…….
It results from weakening of arterial wall by microbial infection.It originates from,1. Embolization of a septic embolus as a complication of infective endocarditis.2. Extention of adjacent suppurative process.3. Circulating organisms directly infecting the arterial wall
Berry aneurysms are saccularOr lobulated bulge arising atthe bifurcation of intracranialarteries.They are geneticallyDetermined.They are important cause ofSubarachnoid hemorrhageAnd infarction .
When the blood enters the dissected wall of the vessel and spreads for varying distance longitudinally.• It may and may not be associated with aortic dilatation.• It can be fatal if dissection ruptures through adventitia leading to sever hemorrhageIt is common in men of 40_60 yr ageWith hypertension and young patientswith Connective tissue abnormalities.
The major risk factor is hypertension.Intimal tear is the 1st step.Hypertension causes aortic medial degeneration by pressure related ischemic injury.Inherited or acquired connective tissue disorders also contributory factors.Dissection occurs b/w inner 2/3 and outer 1/3 of media.
There are 2 types of classifications 1.DeBakey classification. 2. Recent classification.
1.Chest pain2.Myocardial infarction3.Aortic insufficiency4.Vascular obstruction5.Cardiac tamponade6.Death due to rupture of dissection into pericardial ,peritoneal ,and pleural cavities. Rapid diagnosis and institution of antihypertensive therapy coupled with surgical procedures permit 65_75% of individuals to be saved.
The most common site of involvement of atherosclerotic aneurysm is???????A. Arch of aortaB.) Thoracic aortaC. Suprarenal abdominal aortaD.infrarenal abdominal aorta
The most common cause of dissecting haematoma is????????A.Cystic medial necrosis.B.Traumatic during cardic catherization.C.Systemic hypertension.D.Marfan syndrome.
Dissecting heamatoma causes separation of aortic wall as under.A. Between intima and mediaB. Between inner 1/3of media and outer 2/3 of mediaC. Between inner 2/3 of media and outer 1/3D. Between media and adventitia.