Vascular / Blood vessels Flashcards
Which is not a feature of malignant hypertension? (March 2017)
a. Diastolic pressure above 110mmHg
b. Fibrinoid necrosis
c. Can occur in previously normotensive people
d. Can complicate 1-5% of patients with essential hypertension
ANSWER: Malignant hypertension is defined as diastolic blood pressure >120mmHg (not 110mmHg) and systolic blood pressure above 200mmHg.
What is the least constituent of an atherosclerotic plaque? (August 2016, March 2017)
a. Platelets
b. Stroma
c. Smooth muscle
d. Inflammatory cells
e. Fat
• Stable plaques are rich in extracellular matrix and smooth muscle
• Unstable plaques are rich in macrophages and foam cells
• Plaque rupture exposes the lipid core and collagen fibres to the circulation which leads to thrombus formation in the lumen
o May cause occlusion or thromboembolism
ANSWER: Platelets would be the least constituent in an atherosclerotic plaque
Regarding aortic dissection, which is true? (March 2016, August 2016, March 2017)
a. 5-10% have no intimal tear
b. 70-80% involve the aortic arch and the proximal descending thoracic aorta
c. Cystic medial necrosis is not commonly found in patients without a dissection
Epidemiology: Peak age 50-65, 75% occur between 40 and 70 years; Male predominance
Aetiology: Medial cystic degeneration is associated with many diseases which predispose to dissection:
- Hypertension (70%) and atherosclerosis
- Structural collagen disorders (Marfans, Ehlers-Danlos, Loeys-Dietz)
- Congenital diseases: coarctation, bicuspid valve, unicuspid valve
- Pregnancy
- Collagen vascular disease (rare)
o Other causes include syphilitic aortitis, crack cocaine use and iatrogenic injury
Pathology:
o Dissections almost universally originate in the thoracic aorta
o Intimal tear leading to formation (and propagation) or a subintimal haematoma
- 5-10% occur without an intimal tear, secondary to haemorrhage in the vasa vasorum
Stanford Classification:
o Stanford A (60%): Involving the ascending aorta +/- descending aorta
o Stanford B (40%): Excludes the ascending aorta, involves the descending aorta and/or aortic arch
ANSWER: 5-10% of aortic dissections have no intimal tear – they are secondary to haemorrhage in the vasa vasorum
An elderly patient has a saccular aortic aneurysm with raised inflammatory markers. What is the most likely diagnosis? (March 2014)
a. Inflammatory aortic aneurysm
b. Mycotic saccular aneurysm
ANSWER: Myocotic saccular aneurysm. Inflammatory aortic aneurysm is more common in younger patients
What is not a cause of aortic dilation? (March 2015)
a. Loeys-Dietz
b. Kawasaki
c. Takayasu
d. Syphilis
e. Ehlers-Danlos
Causes of ascending aortic dilation:
o Senile/atherosclerotic ectasia/hypertension
o Aneurysm of the ascending aorta
o Aortic dissection
o Aortic valve pathology
- AV stenosis, Subvalvular AS, AV regurg, Bicuspid AV
o Congenital:
- Coarctation of the aorta, PDA, TOF, Truncus arteriosus, VSD, Transposition with tricuspid atresia
o Aortitis:
- Takayasu, Kawasaki disease (mild dilation is common) – predilection for coronary vessels, Syphilis
o Connective tissue disorders:
- Marfan disease & Loeys-Dietz, Ehlers-Danlos disease, Osteogenesis imperfecta
ANSWER: All can cause aortic dilatation, except Kawasaki’s is typically mild. All but Kawasaki’s are listed as causes of ascending aortic aneurysm.
What is not a cause of renal microaneurysms? (August 2016)
a. Diabetic nephropathy
b. Neurofibromatosis
c. Hypertension
Common causes of renal aneurysms or microaneurysms:
o Atherosclerosis, Iatrogenic, PAN
Uncommon causes: o AML (especially with tuberous sclerosis) o Arteriolar nephrosclerosis (malignant) o Atrial myxoma (metastatic) o Congenital or acquired AV communications o Bacterial endocarditis and multiple mycotic aneurysms o Connective tissue disorders (e.g. SLE & RA) o Dissecting aneurysm o Drug abuse angiitis o FMD o Homocysteinuria o NF o RCC o Renal transplant rejection o Takayasu o Thrombocytopaenic purpura o Trauma o Wegeners/Churg-Strauss
ANSWER: Diabetic nephropathy is not a cause of renal microaneurysm
Regarding Marfans, which is correct (August 2016):
a. Cystic medial degeneration
Marfan
o AD mutation, 1/3 spontaneous mutation, High penetrance with variable expression
o Defect in fibrillin 1 (FBN1) gene on the long arm of chromosome 15, Responsible for the cross linking of collagen
o CVS complications are predominantly due to cystic medial necrosis of the vessels - most frequent cause of death
- Aortic root dilation
- Myxomatous degeneration of the MV resulting in MV prolapse
- Aortic aneurysm / dissection
- Arterial dissection
- AV regurgitation
- Aortic coarctation
- Pulmonary arterial dilatation
ANSWER: Marfan’s is associated with cystic medial degeneration in blood vessels
Patient with back and chest pain. There is contrast in the media of the aorta. What is the most likely diagnosis? (September 2013)
a. Dissection
b. Rupture
c. Penetrating atherosclerotic ulcer
d. Aneurysm
ANSWER: Dissection by definition is separation of the inner two thirds of the media from the outer third, therefore contrast splitting the media suggests dissection. However, penetrating ulcers may demonstrate contrast within the media in some cases.
What is a true association? (March 2015)
a. Cerebral thrombosis from prothrombin G20210A mutation
b. Migratory superficial thrombophlebitis is from metastatic microthrombi
c. Spontaneous DVT in patients older than 60 suggests Factor V Leiden
G20210A mutation:
o Second most common inherited thrombophilia after Factor V Leiden
o Mutation in the gene coding for Prothrombin II
o Associated with DVT and PE, with increasing case reports associating dural venous thrombosis (especially SSS)
Migratory thrombophlebitis aka Trousseau Syndrome:
o Provocation of venous thrombosis secondary to an underlying malignancy
o Hypercoagulability rather than metastatic microthrombi
Factor V Leiden:
o Hypercoagulability caused by a mutation in clotting factor V
o Factor V Leiden suspected in cases of multiple episodes of superficial or deep venous thrombosis under the age of 50
- May manifest in pregnant women
- Most carriers never develop signs or symptoms
ANSWER: Cerebral thrombosis is associated with prothrombin G20210A mutation (Prothrombin II)
A 35 year old female has a soft tissue mass in the palm of her hand. It has high T1, partially suppresses on STIR and demonstrates heterogenous enhancement. What is the most likely diagnosis? (March 2017)
a. Lipoma
b. Schwannoma
c. Haemangioma
d. Haematoma
e. Melanoma
Schwannoma: Low T1, may have cystic characteristics, enhances
Haemangioma: Iso to high T1 to skeletal muscle, partial enhancement; ?contain fat
ANSWER: The lesion is most likely a haemangioma
Which are true associations? (August 2014)
a. CMV and HCC
b. HHV-8 and Kaposi sarcoma
c. EBV and plasmacytoma
d. HTLV and Hodkin lymphoma
e. HPV and nasopharyngeal carcinoma
CMV associated neoplasia:
o Mucoepidermoid carcinoma (secondary to chronic salivary gland infection)
o Possible role in prostate cancer
HHV-8 associated neoplasia:
o Kaposi sarcoma
o Primary effusion lymphoma
o Subtypes of Castleman’s disease
EBV associated neoplasia: o Burkitt lymphoma o Hodgkin lymphoma (subtypes) o Gastric carcinoma o Nasopharyngeal carcinoma
HTLV (human T lymphotropic virus) associated neoplasia:
o Adult T cell lymphoma/leukaemia
HPV associated neoplasia:
o Cervical cancer (strongest association – subtypes HPV 16 and 18)
o Vulval and vaginal cancers
o Penile cancer
o Anal cancer
o Oropharyngeal cancer
o Possible association with nasopharyngeal carcinoma
ANSWER: HHV-8 is associated with Kaposi sarcoma. There is a proposed association between nasopharyngeal cancer and HPV.
Fibrinoid necrosis is seen in which of the following? (March 2014)
a. Myocardial infarction
b. Vasculitis
c. TB
d. Trauma
Myocardial infarction: coagulative necrosis
Vasculitis: fibrinoid necrosis
o Polyarteritis nodosa and malignant hypertension
TB: caseous necrosis
Traumatic: fat necrosis
Cerebral infarction and abscess formation: liquefactive necrosis
ANSWER: Fibrinoid necrosis is seen with vasculitis
Which vasculitis involves the renal arteries?
a. Polyarteritis nodosa
PAN
- Systemic inflammatory necrotizing vasculitis that involves the small to medium sized arteries. Usually fatal if untreated
Epidemiology:
M>F, 5th to 7th decades, 20-30% HbSAg positive
Clinical:
- Present with systemic or focal non-specific constitutional symptoms
- Localised symptoms relate to ischaemia or infarction or affected tissues and organs
(Peripheral neuropathy; CNS: cognitive dysfunction, decreased alertness, seizures, focal neurological deficits; Skin: purpura, livedo reticularis, ulcers, nodules, gangrene; Kidney: proteinuria, renal impairment, hypertension; GI: abdominal pain, GI bleeding, bowel infarction, perforation (rare); Heart: myocardial infarction or congestive cardiac failure; Eye: scleritis; Genitals: testicular infarction)
Sites of involvement: Renal 80-90% (Most prominent site and major cause of death) Cardiac 70% GI tract 50-70% Hepatic 50-60% Spleen 45% Pancreas 25-35% CNS complications in 20-45% Pulmonary circulation typically spared, bronchial arteries in uncommon cases
Pathology:
- Transmural necrotizing inflammation of the vessel wall leads to microaneurysm formation and focal rupture
- Microaneurysm formation more common at branch-points
- Fibrinoid necrosis in the vessels results in thrombosis and end-organ infarction
- Different stages of inflammation can occur within the same vessel at different points
ANSWER: PAN predominantly involves the renal arteries
PAN spares: (March 2014)
a. The pulmonary circulation
b. The renal circulation
ANSWER: PAN spares the pulmonary circulation
What is false regarding granulomatosis with polyangiitis (Wegeners)? (September 2013, March 2016, March 2016, August 2016)
a. Renal artery vasculitis
b. Upper respiratory tract necrotizing granulomas
c. Lower respiratory tract necrotizing granulomas
d. Pulmonary artery vasculitis
e. Glomerulonephritis
Granulomatosis with polyangiitis
- Multisystem, necrotizing non-caseating granulomatous vasculitis affecting small to medium sized arteries, capillaries and veins
- Most common in the respiratory system and the kidneys
Pathology:
- Immune mediated vascular injury (Necrotising granulomas with associated vasculitis)
- 90% have positive cANCA (Levels correlate with disease activity)
Classification: - Classic: triad of pulmonary, upper respiratory tract and renal disease - Limited: does not have full triad • Usually upper respiratory tract only • Renal only uncommon - Widespread: • Additional organ involvement including skin (50%), eyes (45%), peripheral nervous system (35%) • Rarely GI and heart
Pulmonary:
- Initially asymptomatic pulmonary fibrosis
- Multiple pulmonary nodules (cavitating in 50%)
- Pleural effusions
- Mediastinal lymphadenopathy
Renal:
- Necrotising glomerulonephritis (60%)
- Occult on imaging
- Clinical: reduced renal function, proteinuria and haematuria
Upper respiratory tract:
- Mucosal ulcerations and granulomatous masses within the nasal cavity
- Adjacent bony and cartilaginous destruction
CNS:
- Rare, <5%
- Cerebral or meningeal granulomatous lesions
- Small vessel CNS vasculitis causing infarcts and arterial occlusion
- Intracranial haemorrhage
- Continuous invasion of an extracranial granuloma
Orbital:
- 40-50%
- Granulomatous disease of the orbit: inflammatory mass with or without proptosis and/or nerve compression
- Small vessel vasculitis: conjunctivitis, scleritis, episcleritis, uveitis, optic neuritis, optic nerve vasculitis, retinitis
ANSWER: GPA does not affect the renal arteries – it causes a necrotizing vasculitis
