Venovo- Venous Information Flashcards
Artery composition
- more muscular, thicker walls
- smaller lumens
- no valves
- more elastic, less compliant
- higher blood flow rates
Vein composition
- thinner walls
- larger lumens
- bicuspid valves
- less elastic, more compliant
- 70% of the body’s blood
- lower blood flow rate
- higher degree of variability
arteries are more ____, less __________.
- elastic
- compliant
veins are more ______, less _______.
- compliant
- elastic
elasticity definition
the ability to return to size/ shape after deformation. It is NOT stretchiness of the vessel
Compliance definition
is the ability to yield to increase pressure
elasticity and compliance have an inverse relationship. The more compliant a vessel is, the ___ elastic it can be.
less
venous valves > 2mm have bicuspid valves to prevent ______.
Reflux
for venous valves, divide the hydrostatic column of blood into small segments, this helps maintain _____.
flow direction
valves open when the blood is flowing ______ the heart and ______ when the pressure gradient is _______.
- toward
- closed
- reversed
the short period of reflux before valves close is
<0.5 seconds
Average diameter of the inferior vena cava
18-24 mm
average diameter of common illiac vein
16-18 mm
average diameter of external illiac vein
14 mm
average diameter of common femoral vein
12 mm
average area of inferior vena cava
300-400mm^2
average area of common illiac vein
200-250mm^2
average area of external illiac vein
150mm^2
average area of common femoral vein
110mm- 125^2
what is the purpose of stenting?
restore lumen area to reduce venous congestion and lower venous pressures
T/F: veins typically have larger diameters and luminal area than their arterial counterparts
True
Physicans often refernce vein area instead of ______.
diameter
Common femoral vein diameter, length, area
- 12 mm diameter
- 60 mm length
- 125 mm^2 area
external iliac vein diameter, length, area
- 14 mm diameter
- 130 mm length
- 150 mm^2 area
common iliac vein diameter, length, area
- 16 mm diameter
- 60 mm length
- 200 mm^2 area
inferior vena cava diameter, length, area
- 18-24 mm diameter
- 140 mm length
- 300- 400 mm^2 area
Recurrent DVT, pulmonary embolism (PE), and post-thrombotic syndrome (PTS) are risk of thrombosis of ____ and ____.
femoral, iliac veins
There are ___ main ways to classify VTE severity
4
T or F: approximately 80% of patients with DVT in the iliofemoral veins are not being treated successfully with conventional therapy
True
what stands for clinical, etiological, anatomical, and pathophysiological
CEAP
In which stages do patients become eligable for deep venous treatments according to CEAP?
stages C3-C6
What was created to supplement CEAP and enable longitudinal patient surveillance
VCSS
an assessment designed specifically for PTS
Villalta
a patient reported quality of life (QoL) assessment
CIVIQ-20
which venous classification tool asks physical and psychological questions?
CIVIQ-20
The (‘16-‘26) CAGR for venous stenting is
7.9%
Stages of _____/ _____ include: anitcoagulation, mechanical prophylaxis, and IVC filter
prevention/ management
stages of ______ include: Throbosis, thrombectomy, and venous stent
intervention
oldest and most common anticoagulation method, oral therapy
warfarin/ coumadin
immediate effect and decreases fatal PE by 75% through injection
Heparin
novel oral anticoagulaion, intented to eventually replace warfarin
NOAC: Rivaroxaban & Apixaban, Dabigatran
Virchow’s Triad includes 3 factors in the formation of venous thrombolism
- venous stasis
- coagulation
- vein damage
what % of DVT occurs in the common femoral or iliac veins?
40%
symptoms of DVT
swelling pain, warmth, enlarged veins and skin discoloration
acute clot age and description
- <14 days
- a clot that is still soft enough and more easily removed
subacute age and description
- 14-28 days
- DVT that is organizing from a soft thrombus into collagenous scar tissue and integrating into the vein
chronic age and description
- > 28 days
- tough, collagenous tissue that has integrated into the wall of the vein
Peripheral Artery Disease (PAD)
- smoking, diabetes, high cholesterol, hypertension
- ages 65+
- both men and women
- high amputation risk
Venous Thrombembolism (VTE)
- obesity, pregnancy, cancer, autoimmue disorders
- most common in 50+, but can occur at any age
- both men and women, but higher in women in childbearing years
- lower amputation risk
consequences of DVT/ PE
- 100k yearly deaths in US
- 548K yearly hospital admissions
- 33% recurrence in 10 years
- 50% develop PTS
- annual healthcare cost $2-10 billion
post thrombotic syndrome
- results from the damage of accumulated chronic DVT
- narrowing causes outflow issues and hypertension
- valve damage causes chronic venous insufficiency
- venous ulcer are common in advanced cases
may-thurner syndrome
- compression of the left iliac vein by right iliac artery
- up to 25% of all DVT cases
suggested treatment of may-thurner syndrome
suggested treatment is removal of acute clot via thrombolysis, angioplasty + stent of compression lesion
DVT & PE prevention three options:
- anticoagulation
- mechanical prophylaxis
- IVC filter
anticoagulation role in DVT & PE prevention
- blood thinning medication
- gold standard
mechanical prophylaxis role in DVT & PE prevention
- compression stockings, pneumatic devices
- gold standard
IVC filter role in DVT & PE prevention
- to help prevent recurrent PE
- does not address DVT
heparin ( acute therapy via injection)
- decreases fatal PE by 75%
- reduces recurrent PE from 30% to 8%
- not feasible long term
coumadin/ Warfarin (continous oral therapy)
- difficult dosage control
novel oral anticoagulation (NOACs)
- dabigatran, rivaoxaban, and apixaban
- expensive
- no reversal treatment
anticoagulation contraindications
- active or recent hemorrhage
- peptic ulcer disease
- previous complications from anticoagulation
- hemorrhagic stroke
- surgery involving brain or spinal cord
- fall risk
anticoagulation complications
- resistance to anticoagulation
- major bleeding
- recurrent PE
mechanical methods of prophylaxis
- graduated compression stockings (GCS)
- intermittent pneumatic compression (IPC) devices
- Venous foot pump (VFP)
What to do for those patients with documented DVT/ PE who are not candidates for anticoagulation and/or do not respond to anticoagulation or mechanical prophylaxis?
IVC filter
Venous disease interventional treatment options
- thrombolysis
- Thrombectomy
- Venous stent
goal of interventional treatment
- reestablishblood flow
- relieve symptoms
- limit the risk of PE
considerations for interventional treatment
- extensive or proximal DVT involving the IVC or iliofemoral veins
- high risk of PTS
- younger patients
- high risk of fatal PE
- DVT despite anticoagulation
- antatomic lesions I.E. may thurner or pelvic tumors
What is thrombolysis?
- systemic or catheter directed
- effective for acute clot removal
thrombolysis limiters:
- risk of bleeding complications
- increased risk of PE
- not effective on chronic thrombus
- doesn’t address cause of compression syndrome
what is thrombectomy?
- surgical, mechanical, or pharmaco-mechanical
- effective for acute clot removal with limits for sub-acute
thrombectomy limiters
- increased risk of PE
- not effective on chronic thrombus
- doesn’t address cause of compression symptoms
when and why should you stent?
- AHA reccomends when other options have been exhausted
- literature shows stenting can restore integrity of the vessel and re-establish flow
venography
- venogram is usually preformed
- AP/RAO/LAO views are recommended
- venous disease, especially compressive lesions, may not be visible
- (look for “pancaking vessel”)
- look for collaterals to indicate underlying problem
- can not completely characterize the disease or degree of stenosis
why IVUS?
- illiac vein size
- confirmation of venous compression syndromes
- stent apposition post deployment
- exact location of IVC bifurcation: stent placement in relation to bifurcation
- identifying disease free landing zone- vital for patency
- extent of stenting as per catheter cm markings
IVUS stent sizing reccomendations:
- (max diameter + min diameter)/2
- add 1-3 mm for self expnding stent size
- post-dilate to actual size of vessel
True or False: Venography is used for both diagnostic and intraprocedural imaging.
True
Which of the following is a negative aspect of venography?
high radiation
What are positive aspects of IVUS?
- Ability to measure diameters and areas
- Accuracy identifying lesion location
- No radiation
- Reduces need for contrast
True or False: Veins are more elastic but less compliant than arteries.
false
