Blood Vessels - The Basics Flashcards
T or F: maintanace of a non-thrombotic state is dependent on laminar flow
True, Laminar Flow is required to prevent thrombosis
What are some basic relaxing and contracting factors secreted from the endothelial lining of vessels?
Relaxing - Nitric Oxide
Contracting - Endothelin
In what conditions might tight junctions become more permeable?
• how are large amounts of solutes moved?
- Vasoactive Agents Secreted or High Blood Pressure will increase the tight junction permeability
- Large Amount of Solute moved by Trancytosis
What are the Two Mechanisms of Vascular Pathology?
- Narrowing or Obstruction
- Weaking (resulting in aneurysm
What vascular pathology has happened here?
Dissecting Aneurysm
• Media has been split in half
What vascular pathology has happened here?
What time frame did it happen in and how do you know?
Acute Narrowing/Obstruction of a vessel
• You can see lines of Zahn indicating that it is a thrombus, clefts of cholesterol indicating that Hypercholesterolemia could be etiology
What vascular pathology has happened here?
• what has caused it, time frame?
Narrowing of Vessel Lumen as a result of intimal thickening can be seen
• More progressive than just acute, resultin from high LDL over a long period of time
What has happened here?
Atherosclerotic aneurysm from Weakening of BVs
What is Glycation?
• Diseases where it is common?
Glycation - non-enzymatic reaction between reducing sugars such as glucose and proteins, lipids, or nucleic acids
**Common in Diabetes, we use Hbg A1C**
What is glycoxidation?
When OXIDATIVE steps are involved ine Glycoxidation
**ROS accelerate this processes
What is a time when you might not want to measure Hbg A1C in a patient?
People who don’t have much Hbg A1 such as Sickle Cell patients or Pts. with alpha thalessemia
In what 3 ways do Advanced Glycation End products (AGEs) contribute to vascular disease?
- Collage Crosslinking promoted
- Glycation of LDL
- Binding to RAGE
How does promotion of collagen cross-linking lead to increased cardiovascular disease?
- Collagen Crosslinking causing Stiffening of Vascular Walls
- Crosslinking also causes entrapment of LDL in the artery walls
How does glycation of LDL promote CV disease?
- Glycation of LDL makes it more prone to get oxidized
- Oxidation of LDL is a MAJOR risk factor of Atherosclerosis
How does binding to RAGE (receptor for advanced glycation end products) lead to CV disease?
- Binding to RAGE promotes Oxidative Stress on the Endothelium
- Also activates Inflammatory Pathways in the endothelial cells
What 3 congenital Anomalies do we need to know for vessels?
- Berry Aneurysms
- Arteriovenous (AV) fistulas
- Fibromuscular Dysplasia
Berry Aneurysms
- What are they?
- Where are they found?
- Why does it happen?
- Dangers?
What/Where:
• Thin-walled arterial outpouching in cerebral vessels specifically at Branch Points
Why:
• Media is CONGENITALLY too thin (attenuated)
Danger:
• Rupture
What is the major complaint of someone experienceing a Berry Aneurysm?
“The worst headache I’ve Ever had”
****What is this?
• What do you think this person complained of when they came to the ED?
Berry Aneurysm - caused by a congenitally thin media
• Probably Said it was the worst headache they’ve ever had
What is an Arteriovenous (AV) fistula?
• Whats a major problem that may result?
• CONGENITAL Abnormal connection between an Artery and a Vein (they don’t go all the way down to capillaries, they just connect)
Major Problem: Susecptible to Hemorrhage and Hypoxia even without Hemorrhage from decreased Surface area of vessel being exposed
*****What has happened here?
AV Fistula - caused by direct connection between an artery and a vein
Fibromuscular Dysplasia
- What is it?
- Type of Vessels Affected?
- Who is it found in?
- Congenital disease causing alternating thickened and thinned arterial walls usually from thickening of the Media
- small to medium sized vessels are affected
- Found in younger women
A young fit woman comes in with hypertension as a result of Fibromuscular Dysplasia.
- What is the most likely cause of the HTN?
- Other risk factors of the disease?
- APPEARANCE?
Cause - hypertension can be caused in patient with Fibromuscular Dysplasia via renal artery constrictions
Other Disease Complications: 10% experience medial dissections
Beads on a String Appearance in affected vessels
****T or F: thickening in this vessel was caused by either an inflammatory or atherosclerotic process.
False, this is from a patient with fibromuscular dysplasia - these patients experience non-inflammatory, non-atherosclerotic thickening of the media
T or F: PRIMARY vascular tumors of large vessels are fairly comon and are often carcinomas
FALSE, they are EXTREMELY RARE and are usually SARCOMAS
What are vascular tumors that arise from the endothelium called?
• what about ones from support cells?
Hemangiomas or Angiosarcomas
Support Cells = Glomus Tumor
Compare Benign and Malignant Tumors with respect to:
- Organization
- Cellularity
Benign:
- Obvious Vascular Channel with Blood
- Lined by monolayer of normal appearing cells
Malignant:
- poor orgnaization of vessels
- more cellular with cytologic atypia
What markers can you use to confirm that the tissue you’re looking at is in fact vascular?
- CD31
- CD34
- D2-40
What is a vascular ectasia?
• Local Dilation of a Blood Vessel
What are the 3 benign vascular ectasias?
- Nevus Flammeus
- Spider Telangectasias
- Hereditary Hemorrhagic Telangectasia
What is a Telangiectasia?
• where is it usually found?
- Telangiectasia - permanent dialation of small BVs
- Typically occurs in mucous membranes and skin
T or F: Vascular ectasias are very benign neoplasms
FALS, these are NOT TRUE NEOPLASMAS
Nevous Fammeus
- Typical Appearance
- Progression
- Life impact
aka port wine
Appearance
• Large Flat patch of purple or dark red skin with well defined borders
Progression
• Starts off flat at birth but become more bumpy and unsighly over time and DOES NOT REGRESS
Life Impact:
• Not any real health impact but the psychosocial element may be huge
****What is this?
• What is the Px?
Nevus Flammus
• No real health impact, BUT they should expect that this will be a long term condition with a high probability of having a psychosocial impact