Week 7: Chp 31: Aortic Artery Disease Flashcards
Aortic Artery Disease is also known as?
an aneurysm
Risk Factors
family history, advanced age, male gender, smoking, atherosclerosis, treated and untreated hypertension, high total serum cholesterol, known coronary artery disease, and genetic and/ or metabolic abnormalities
What is the most common site for a dissecting aneurysm?
Thoracic (descending) aortic aneurysm
15000 people in the U.S. die each year of what aneurysm?
abdominal aortic aneurysm (AAA)
Which risk factor is most important?
smoking
-patient can control (modifiable)
What is a major factor in aortic aneurysms?
genetics
What is the hereditary disease most closely linked to an aneurysm?
-Marfans Syndrome
>affects connective tissues, patient is tall and thin with disproportionately long arms, legs, fingers, toes
>this syndrome results in the degeneration of the elastic fibers of the aortic media
What disorders cause AAA (abdominal aortic aneurysm)
- syphillis
- patients born with a bicuspid aortic valve
- Ehlers-Danlos syndrome, a rare genetic disorder
What causes aneurysms?
- chronic inflammation (aortitis)
- blunt trauma (usually from motor vehicle accidents, can cause aneurysms in the descending thoracic or abdominal aorta)
- blunt trauma can cause rupture of aorta
- hypertension
- marfans syndrome
- atherosclerosis
What is an aneurysm?
a permanent localized dilation of an artery that forms when the middle layer (media) of the artery is weakened, producing a stretching effect in the inner layer (intima) and outer layers of the artery
- while the artery widens, tension in the wall increases, further widening occurs, and the aneurysm enlarges
- the diameter of the artery can be enlarged to at least two times the normal circumference
Aneurysms can occur where?
in the three different areas of the aorta
- ascending aortic aneurysm; located in the arch of the aorta
- descending aortic aneurysms or thoracic aneurysms are located above the diaphragm
- abdominal aortic aneurysms (AAA); located below the diaphragm in the abdomen (most common location)
Aneurysms are classified as 2 categories
True or False
True Aneurysms
all three layers of the arterial wall are weakened
-further classified by their shape or form
-most common forms are saccular and fusiform
(saccular only projects from only one side of the vessel; a fusiform aneurysm develops if an entire arterial segment becomes dilated
True Aneurysm: Saccular
projects from only one side of the vessel
True Aneurysm: Fusiform
an entire arterial segment becomes dilated
False aneurysm
not a distortion of the vessel wall but rather a leak from the artery
-pseudoaneurysm
False Aneurysm: Pseudoaneurysm
- leak from the artery
- the leak is confined by the surrounding tissues, and eventually a blood clot forms
- typically caused by iatrogenic trauma that punctures the artery
- known complication of percutaneous arterial procedures such as arteriography
Clinical Manifestations
usually cause no symptoms and are found when a patient is evaluated for another medical condition
- typically occur when a complication such as dissection or rupture occur
- may be a palpable pulsatile mass in the abdomen with the AAA
- sometimes patient presents with chest, back, or flank pain depending on the location of the aneurysm
- the pain is typically not related to any activity and occurs spontaneously
- pain generally reflects a change in the aneurysm that needs immediate attention
- AAA are usually small do not cause any symptom
- majority of thoracic aneurysms are silent, with rupture or dissection constituting first symptoms
- overall only 5% to 10% of patients experience symptoms such as chest, back, or flank pain depending on the location of the aneurysm
Medical Management: Diagnosis
Computed tomography scanning with IV contrast is the gold standard for assessing the size and location of an abdominal or thoracic aneurysm
- abdominal ultrasound or transthoracic echocardiography (TTE) (can be done quickly and efficiently at the bedside and also because of their noninvasive nature and lack of radiation)
- Cardiac MRI (imaging modality that has shown improved sensitivity and specificity versus TTE in detecting aortic dilation) (lack of radiation exposure with MRI compared with CT may make it the imaging modality of choice for aortic dilation
- an ECG is also routinely done to rule out MI because complications of aneurysm usually involve chest pain
Treatment: Medications
focused on reducing the growth rate and preventing the complications of aneurysms
- antihypertensives
- macrolides
- tetracyclines
Medications: Antihypertensives
hypertension is an important risk factor for rupture, so BP is aggressively managed with antihypertensive medications
- angiotensin-converting enzyme inhibitors (ACE inhibitors)
- angiotensin II receptor blockers (ARBs)
- beta blockers
Medications: macrolides and tetracylcines
antibiotics that may inhibit secondary infections implicated in aneurysm development
-have been proposed as a treatment for AAA with varying rationales and degrees of success
Macrolides
antibiotic
-inhibit abdominal aortic aneurysm (AAA) progression by reducing secondary infection within aortic wall