Pathology Flashcards
Physically what causes an Aortic Dissection?
Tear in the intima, blood then flows between the intima and media, causing a dissection. Blood can then rip though all of the walls into the adventitia as well.
What are the two main causes of Aortic Dissection? And where is the most common area?
Must have Pre-existing weakness of media*
- Hypertension causes arteriolosclerosis of the vasa vasorum, thus reducing O2 flow to the adventitia and media weakening it. HTN is most common cause
- inherited defect of CT - Marphans or Ellers Danlow
Marfan Syndrome
CT disease, defect of fibrillin. Lanky, tall, and thin. Can have nocturnal blindness or astigmatism. Also associated with aortic dissection.
Ehlers–Danlos syndrome
CT disease, defect in collagen. Hyperflexible joints. Risk of aortic dissection.
Complications of Aortic Dissection
- Pericardial tamponade if dissection goes back towards heart and filled the pericardium.
- If dissects inferiorly, can go to renal artery and occlude it (end organ ischemia of kidney)
- Ruptures in mediastinum, resulting in fatal hemorrhage
What causes an aneurism? What are the two main places in the aorta that aneurisms occur? Causes.
Weakness in wall*
- Thoracic aneurism - tertiary syphilis* causing arteritis, resulting atrophy of media and adventitia, thus ballooning of aorta. Tree bark appearance of aorta*
- Abdominal - Below renal arteries and above aortic bifurcation. Cause is atherosclerosis*
Complication of thoracic aortic aneurism?
- Dilatation of aortic root, pulling apart aortic valve causing Aortic Insufficiency.
- Thrombosis along wall of aneurism due to turbulent flow, can cause embolism - Stroke
How does atherosclerosis cause an aneurism? Feared complication? Classic patient?
Thickening of wall creates a larger diffusion distance for O2, weakens wall causing ballooning. Classic patient is male smoker over 60. Pulsatile abdominal mass*
-AAA Rupture can be fatal - hypotension, pulsatile abdominal mass, and flank pain. Medical emergency.
Main cause of thoracic aortic aneurism?
Tertiary syphilis
Main cause of AAA?
Atherosclerosis
Definition of vasculitis? Symptoms.
Inflammation of blood vessel wall. Arteries or veins.
Etiology is usually not known.
Nonspecific symptoms (inflammation - fever, myalgia…)
Symptoms of organ ischemia (thrombosis or post inflammation healing causes fibrosis and thus lack of blood flow to organ)
Temporal (Giant Cell) Arteritis. Symptoms? How to diagnose? Treatment? When to treat?
Most common in older adults (>50 y/o female)
- Affects aortic artery (temporal - headache*, opthalmic - visual disturbances, jaw claudication, flu-like symptoms (joint and muscle pain)
- ESR is elevated* >100
- Dx: Biopsy - granulomatous vasculitis - fibrosis causes narrowing of vessel lumen, giant multinucleate cells
- Tx: Corticosteroids - treat ASAP, do not wait for biopsy results - if opthalmic artery is involved permanent vision loss can occur
Takayasu Arteritis. Symptoms? Diagnosis? Treatment?
Adult < 50 (classic is young Asian female)
Granulomatous vasculitis of Aortic Arch at branch points*
-Weak or absent pulses in upper extremities
-Visual and neurologic symptoms
-ESR is elevated
Tx: Corticosteroids
Polyarteritis Nodosa. Symptoms? Diagnosis? Treatment? What is it associated with?
Medium vessel vasculitis. Necrotizing vasculitis involving any organ EXCEPT the lungs.
-Hypertension if renal artery
-Abdominal pain with melena if mesenteric artery
-Neurologic disturbances
-Skin lesions
-Fibrinoid Necrosis (transmural inflammation) - can cause ‘String-of-Pearls’ Appearance*
Associated with serum HBsAg (hep B surface antigen)
Tx: Corticosteroids or Cyclophosphamide (fatal if untreated)
Mechanism of corticosteroids?
mech
Mechanism of Cyclophosphamide?
mech
Kawasaki Disease. Symptoms? Diagnosis? Treatment?
Medium vessel vasculitis. Child (Asian) under 4 years, rash on palms and soles, fever, conjunctivitis, cervical lymphadenopathy (mimics viral infection).
- Coronary artery is usually involved: risk is thrombosis with MI or coronary aneurism with rupture
- Tx: Aspirin (protects against thrombus/embolism) and IVIG
Mechanism of Aspirin? Who do you never give it to?
COX 1 and 2 inhibitor - decreases TXA2 (thromboxane A2) -leads to permanent inactivation of platelets - cannot aggregate and form a clot
-Never give to a child with a systemic viral infection, can cause Reyes syndrome
Mechanism of action of IVIG?
Mech
Reyes Syndrome
Encephalopathy and massive liver necrosis - a child with a viral illness who was administered Aspirin.
Buerger Disease. Symptoms? Diagnosis? Treatment?
Medium vessel vasculitis. A necrotizing vasculitis involving the digits*. Presents in a SMOKER** with ulceration, gangrene, auto-amputation of fingers and toes, and also Raynaud phenomenon.
Tx: Stop smoking
Raynaud Phenomenon
Vasospasm resulting in discoloration. In ditigts, first turn white, then become hypoxic and turn blue, then return to red once blood flow is returned.
Wegener Granulomatosis. Symptoms? Diagnosis? Treatment?
Small vessel vasculitis. Necrotizing granulomatous vasculitis involving NASOPHARYNX, LUNGS, KIDNEY*
-C disease - We’c’ener - Nose, lung, kidney
-c-ANCA
-Cyclophosphamide is tx
Sinusitis/epistaxis
Hemoptysis with bilateral lung infiltrates/nodules
Hematuria due to RPGN (rapidly progressive glomerular nephritis)
Hemoptysis
Coughing up blood.