Clinical Aortic Disease Flashcards
For what do diseases of the aorta account?
significant morbidity (having the disease) and mortality (died from disease).
What happens to the aorta in terms of energy during systole?
It’s kinetic energy is converted to potential energy as the aorta is distended.
What happens to the aorta in terms of energy during diastole?
It’s potential energy is converted back to kinetic energy as it recoils (due to its elasticity) and pushes the blood into the systemic circulation.
What is important to remember about systolic pressure?
It is a function of blood volume, a function of compliance of the aorta, and resistance of blood flow in the peripheral vasculature.
Are there sensors in the aorta and heart that will regulate systolic pressure?
YES. They send afferent signals through the Vagus nerve to the brain, telling the aorta to distend, the heart to change HR, and the peripheral resistance to change.
Of what does the tunica intima consist?
a single layer of endothelium
Of what does the thick tunica media consist?
a thick smooth muscular wall with lots of elastic fibers and collagen fibers. This provides its strength and elasticity.
Of what does the outermost tunica adventitia consist?
loose connective tissue, some collagen, and the vaso vasorum (blood supply to the aorta).
With what is aortic degeneration associated?
age, men, hypertension, smoking, and hypercholesterolemia.
Do athletes tend to maintain their elasticity and distensibility as they age?
YES :)
What happens to the collagen/elastin ratio as we age?
It increases :(
What pathological processes can lead to disease of the aorta?
- cystic medial degeneration
- atherosclerosis
- inflammatory disorders
- trauma
What is cystic medial degeneration?
characterized by smooth muscle cell necrosis, apoptosis, degeneration of elastic fibers within the media, cystic spaces, and extension of the adventitia, thus weakening the wall making it more prone to aneurysm and dissection. All of these occur most importantly in the ascending aorta.
What is a well known syndrome of cystic medial degeneration?
Marfan syndrome: autosomal dominant mutation in fibrillin 1 gene affecting the connective tissue causing dilatation and aneurysm of the aortic root, dilatation of the pulmonary artery, and dilatation or dissection of the descending thoracic or abdominal aorta.
You can also see musculoskeletal and ocular problems.
What is another syndrome of cystic medial degeneration?
Ehlers-Danlos syndrome: multiple genetic inheritance patterns and causes arterial mid-sized rupture of the thoracic or abdominal vessels (frequently abdominal aorta). It is characterized by articular hypermobility, skin extensibility, and tissue fragility.
There are 6 types.
What is Loeys-Dietz syndrome?
another form of cystic medial degeneration. It is inherited autosomal dominantly and is a very tragic form of degeneration causing aggressive aneurysms and dissections occurring distal to the aortic root. Live to 37.
What are some more common cystic medial degenerations?
- familial aortic aneurysm/dissection syndromes
- bicuspid aortic valve (BAV)= most common congenital heart malformation
- autosomal dominant polycystic kidney disease
- Neurofibromatosis= renal arteries
- Turner Syndrome= aortic root and thoracic aorta
How does atherosclerosis affect the aorta?
in the arch, descending thoracic, and abdominal aorta. This will cause complex atheromatous plaques, which can embolize causing resultant stroke or peripheral arterial occlusion.
Cholesterol embolization syndrome may also occur following angioplasty as an embolus travels distally (will see purple toes) but is usually transient and doesn’t require heparin since it resolves.
