<s>[INST] context: • “90% all abdominal aortic aneurysms are related to atherosclerotic disease and most of these aneurysms are below the level of renal arteries.”
• Aneurysm: permanent and irreversible localized dilatation of blood vessel with at least 50% increase in diameter
• Ectasia: dilatation <50% of normal diameter
• AAA (abdominal aortic aneurysm) is diagnosed if diameter >3 cm in males or >2.6 cm in females
• MC location: Aorta >Iliac >Popliteal >Femoral (AIPF)
• MC site of extra-cranial arterial aneurysm is infrarenal aorta
• MC site of peripheral aneurysm: Popliteal aneurysm
• Degenerative aneurysms (caused by atherosclerosis) are MC AAA (90%)
• Width of aneurysm is most important predicting factor of rupture.
• Juan Parodi introduced endovascular aortic aneurysm repair (EVAR).
Classification
• True (all three layers of vessel are involved), false (do not have all three layers of vessel)
• Infected (mycotic) aneurysm are false aneurysm
• Dissecting aneurysm (dissection with aneurysmal dilatation of false lumen)
• Fusiform (symmetrical enlargement involving whole circumference of artery)
• Saccular (affect only part of the arterial circumference) have higher risk of rupture [/INST] question: Most common cause of abdominal aortic aneurysm is: | options: A: Trauma B: Vsculitis C: Syphilis D: Atherosclerosis | answer: D </s>