Vascular disease notes Flashcards
What factors can alter blood flow in and out of organs? 5
Variety of conditions such as
1. Increase in vessel pressures
2. Thrombosis/tumor invasion
3. Atherosclerosis
4. Congenital abnormalities
5. Aneurysms.
What are normal aortic flow patterns? 2
- Proximal: moderate waveform
- Distal: high resistance waveform.
What is the resistance pattern of the renal artery?
Low resistance.
What is the resistance pattern of the SMA pre-prandial and post-prandial? 2
- Pre-prandial: high resistance
- Post-prandial: low resistance.
What characterizes normal portal venous flow? 2
- Hepatopedal
- Monophasic flow with slight undulations.
What is the flow pattern of the hepatic vein and IVC?
Phasic flow influenced by the cardiac and respiratory cycles.
What are the normal measurements for the aorta? What is considered anuerismal in terms of size? 3
- Proximally: ~2.0 - 2.5 cm
- Distally: ~1.5 cm.
- An aorta is considered aneurismal with an AP diameter of 3 cm or greater.
What is the size range for the IVC?
5 – 29 mm (usually < 25mm).
What are indications for arterial assessment? 4
- Pulsatile abdominal mass
- Abdominal pain
- Abdominal bruit
- Hemodynamic compromise of the lower limbs.
Define arteriosclerosis.
Hardening of the arteries.
What is an atheroma?
Lipid deposit in the arterial intima.
What is atherosclerosis?
A form of arteriosclerosis affecting large and medium arteries.
What is a plaque in the context of arterial diseases?
Platelets forming a cap over a fat deposit.
What are the characteristics of atheromatous disease?
Lipid deposits on the intimal lining of any artery, leading to fibrosis and calcification.
What are the common causes of aneurysms? 4
- Atherosclerosis, syphilis
- Systemic infections
- Cystic medial necrosis
- Other diseases like Marfan’s.
What are the risk factors for abdominal aortic aneurysms (AAA)? 5
- Men >60 years of age
- Smoking
- Hypertension
- Family history
- Hypercholesterolemia.
What are the signs and symptoms of AAA? 6
- Patients are generally asymptomatic
- Palpable mass
- Incidental finding on x-ray
- Lower back pain
- Abdominal pain
- Leg pain.
What are the two types of AAA? 2
- Fusiform: uniform tubular swelling
- Saccular: sac-like protrusion towards one side.
What is the sonographic appearance of AAA? 3
- Dilation of the aorta 3 cm or greater
- Aortic wall irregularities
- Thrombus on the anterior and lateral walls.
What is the protocol for measuring an AAA?
- Place calipers outer to outer wall, measure perpendicular to the vessel
- Document length, width, AP dimensions, shape, location, wall thrombus, and flow pattern.
What are the complications of AAA? 4
- Stenosis/occlusion
- Rupture
- Dissection
- Thrombosis.
What is the mortality rate associated with AAA rupture? 2
- Mortality rate: >50%
- Operative mortality rate: >40-60%.
What are the types of splanchnic artery aneurysms? 4
- Celiac
- SMA
- IMA
- Most commonly affects the splenic artery.
What are renal artery aneurysms commonly associated with? 2
Atherosclerosis and polyarteritis.
What is a pseudoaneurysm?
Blood escapes through a tear in the vessel wall and is contained by surrounding tissues.
What is an arteriovenous (AV) fistula?
An abnormal communication between an artery and vein, often secondary to trauma.
What are common findings in vascular stenosis? 3
- Narrowed lumen
- Post-stenotic dilatation
- Increased velocities at stenosis.
What does renal artery stenosis cause? 2
- Uncontrollable hypertension
- Decreased glomerular filtration rate.
What do we look for when assessing the IVC? 4
- Changes with respiration
- Compressibility
- Echo-free lumen
- Patency.
Where does IVC dilate occur? and what is it associated with? 8
Caliber increases below the point of obstruction and is associated with
1. Right ventricular failure
2. Pulmonary hypertension
3. Pericardial tamponade
4. Atrial tumor
5. AV fistulas
6. Congenital IVC valve
7. Extrinsic compression
8. Atherosclerotic heart disease.
What are the signs and symptoms of Dilated IVC? 4
- Abdominal pain
- Ascites
- Hepatomegaly
- Lower extremity edema.
What types of tumors can affect the IVC? 3
- Primary
- Metastatic
- Extension tumors.
What are the characteristics of primary IVC tumors?
They are uncommon and include leiomyoma and leiomyosarcoma.
What is the most common metastatic tumor affecting the IVC?
Renal cell carcinoma (RCC).
What is the sonographic appearance of IVC tumors? 4
- Intraluminal echogenic foci
- Can be isoechoic
- Caliber of IVC increased
- Loss of respiratory changes.
What is IVC thrombosis?
A life-threatening condition and the most common abnormality of the IVC, which spreads from another vein.
What is the sonographic appearance of IVC thrombosis? 4
- Intraluminal filling defect (low-medium level echoes)
- Expanding the vessel
- Echogenicity of the thrombus depends on its age
- Respiratory changes decreased or absent.
What are the signs and symptoms of IVC thrombosis? 5
- Leg edema
- Lower back pain
- GI complaints
- Enlarged liver
- Ascites.
What is useful in diagnosing IVC thrombosis?
Color Doppler, which will show no flow in the region of the thrombus.
What is the treatment for IVC thrombosis?
IVC filters may be used for treatment.
What is renal vein thrombosis? 2 (think how it affects or occurs in infants and adults)
A serious complication in a dehydrated or septic infant, and in adults, it occurs due to shock, renal tumor, renal transplants, or trauma.
What are the signs and symptoms of renal vein thrombosis? 3
- Flank pain/mass
- Hematuria
- Proteinuria.
What is the sonographic appearance of renal vein thrombosis? 5
- Enlarged kidney
- Hypoechoic
- Dilated renal vein
- Filling defects of variable echogenicity
- Decreased or absent venous signal.
What are common congenital abnormalities of the IVC?
Duplication and transposition are the most frequent congenital abnormalities.
What is hepatic congestion?
Passive edema of the liver secondary to vascular congestion, related to heart failure.
What is the sonographic appearance of acute hepatic congestion? 4
- Enlarged liver
- Dilated IVC with no respiratory changes
- Highly pulsatile hepatic veins
- Pulsatile portal vein flow.
What is portal hypertension?
An increase in portal venous pressures, classified into presinusoidal and intrahepatic types.
What are the causes of presinusoidal portal hypertension?
PV and SV thrombosis, resulting in ascites, splenomegaly, and varices.
What is the most common cause of intrahepatic portal hypertension?
Cirrhosis.
What is the sonographic appearance of portal hypertension? 6
- Dilated PV in early stages
- Collateral flow
- Patent umbilical vein/coronary vein
- Ascites
- Splenomegaly
- Changes in portal flow.
What are the five most common collateral routes in portal hypertension? 5
- Gastroesophageal
- Paraumbilical
- Splenorenal/gastrorenal
- Intestinal
- Hemorrhoidal.
What is the treatment for portal hypertension?
Portosystemic shunts to decompress the PV system, including TIPS (Transjugular Intrahepatic Portosystemic Shunt).
What is portal vein thrombosis? What is it caused by? 4
A clot in the portal venous system caused by
1. Malignancy
2. Infection/inflammation
3. Trauma
4. Splenectomy.
What is Budd-Chiari syndrome?
A rare condition characterized by obstruction of hepatic veins with possible IVC occlusion.
What are the causes of Budd-Chiari syndrome? 4
- Coagulation/congenital abnormalities
- Trauma
- Oral contraceptives
- Tumor invasion (HCC).
What is the sonographic appearance of Budd-Chiari syndrome? 6
- Stage dependent
- Enlarged liver (acute)
- Poor visualization of hepatic veins
- Possible thrombus in IVC
- Caudate lobe enlarged/hypoechoic
- Absent or reversed HV flow.
What is a splenic infarct?
A common cause of a focal splenic lesion due to occlusion of the splenic artery, presenting with sudden onset LUQ pain.
What is the sonographic appearance of a splenic infarct?
Hypoechoic, wedge-shaped/round area that becomes more hyperechoic over time.
What can a renal infarct be?
Can be segmental or diffuse, with appearance depending on time.
What is the sonographic appearance of a renal infarct? 2
- Early: hypoechoic
- Resolving: echogenic. Renal function often remains normal.
