Pulmonary diseases of vascular origin(pulmonary embolism)

1. Pulmonary Diseases of
Vascular Origin

2. VASCULAR PULMONARY DISEASES
 PULMONARY EMBOLISM (with or usually WITHOUT
infarction)
 PULMONARY HYPERTENSION, leading to cor
pulmonale
 HEMORRHAGIC SYNDROMES
 GOODPASTURE SYNDROME
 HEMOSIDEROSIS, idiopathic
 Granulomatosis with polyangiitis ( formerly Wegener
Granulomatosis)

3. Pulmonary Embolism, Hemorrhage, and
Infarction
 95% of all pulmonary emboli arise from thrombi within the
large deep veins of the lower legs, typically originating in the
popliteal vein and larger veins above it.
 Thromboembolism causes 50,000 deaths per year in the USA.
 Predisposing causes :
 Prolonged bed rest, Surgery (orthopedic), Disseminated
cancer, CHF, severe trauma (burns, fractures),
Hypercoagulability states
 Pregnancy or birth control pills (high estrogen)

4. Pulmonary Thromboembolism
 Outcomes of embolic pulmonary arterial occlusion: depends
on size of embolus (vessel) & cardiopulmonary status of the
patient (circulation).
 There are two important consequences:
 An increase in pulmonary artery pressure from blockage of
flow, diminished cardiac output, right-sided heart failure
(acute cor pulmonale), or even death
 Ischemia of the down-stream pulmonary parenchyma.
 Usually hypoxemia develops, as a result of multiple
mechanisms

5. Large pulmonary thromboembolus

6. Pulmonary Thromboembolism:
Morphological Changes
 Large embolus in P.Trunk or Saddle embolus  Sudden Death,
therefore no morphologic alterations in the lung.
 Smaller emboli in medium-sized and small arteries → ischemic
damage to endothelial cells or occlusion 
 Lung hemorrhage
 Pulmonary infarction (bronchial arterial flow)
 the lungs are oxygenated not only by the pulmonary arteries but also by bronchial
arteries and directly from air in the alveoli. Thus, infarction is the exception rather
than the rule, occurring in as few as 10% of patients with thromboemboli. The more
peripheral the embolic occlusion, the more likely is infarction.
 About 75% of all infarcts affect the lower lobes, and more than half are
multiple.
 Wedge shaped coagulative necrosis, may be with hemorrhage, fibrinous
exudate on the pleura
 Fibrosis

7. Saddle embolus

8. Hemorrhagic pulmonary
infarction

9. Pulmonary Thromboembolism:
Clinical Presentation
 Clinical Presentation: asymptomatic; most (60% to 80%) are
clinically silent because they are small. the bronchial circulation
sustains the viability of the affected lung parenchyma, and the
embolic mass is rapidly removed by fibrinolytic activity.
 If more than 60% reduction in blood flow  Acute cor
pulmonale & sudden death (5%)
 Obstruction of small to medium pulmonary branches  Sudden
dyspnea, chest pain due to infarction(10% to 15% of cases)
 Recurrent multiple emboli & infarcts leading to pulmonary
hypertension and chronic right-sided heart failure(<3% of
cases).
 Prognosis: one attack  30% recurrent attacks

10. Pulmonary Hypertension
 Pulmonary blood pressure about one-eighth of systemic
pressure.
 Pulmonary hypertension (defined as pressures of 25 mm Hg
or more at rest) is most often secondary
 Causes of secondary hypertension: Cardiac disease, Chronic
lung disease, Inflammatory vascular disease, Recurrent
thromboembolism, Congenital left-to-right shunts
 Arises in one of two ways:
 Decrease in cross sectional area of pulmonary vascular bed
 Increase in pulmonary vascular flow

11. VERY thickened arteriole
in pulmonary
hypertension
NORMAL pulmonary
arteriole

12. Primary/Idiopathic Pulmonary
Hypertension
 The vast majority of cases are sporadic and only 6% have the
familial form with an autosomal dominant inheritance.
 More in young females 20 to 40 years of age
 Cause : probably genetic
 Familial: germ line mutation in TGF-β pathway (bone
morphogenetic protein receptor, type 2 (BMPR2)).
 Sporadic : mutation in serotonin transporter gene (5HTT)
 Pathogenesis: Endothelial cell dysfunction & smooth muscle
proliferation → vasoconstriction
 Poor prognosis: severe respiratory insufficiency and cyanosis,
and death usually results from right-sided heart failure
(decompensated cor pulmonale) within 2 to 5 years of the
diagnosis.

13. Pathology of pulmonary hypertension
 Main arteries  Atheroma
 Small arteries & arterioles  medial hypertrophy and intimal
fibrosis
 In long standing primary cases  Complicated Plexiform
Lesions (Plexogenic Pulmonary Arteriopathy) , capillary
formations → producing a network, or web, that spans the
lumens of dilated thin-walled, small arteries

14. Vascular changes in pulmonary
hypertension.
A, Gross photograph of atheroma
formation, a finding usually limited to
large vessels. B, Marked medial
hypertrophy. C, Plexogenic lesion
characteristic of advanced pulmonary
hypertension seen in small arteries.

15. Diffuse Alveolar Hemorrhage Syndromes
 Clinically: Hemoptysis, Anemia, Diffuse pulmonary infiltrates
 They include:
 Goodpasture syndrome
 Idiopathic pulmonary hemosiderosis
 Granulomatosis with polyangiitis.

17. Goodpasture Syndrome
 Goodpasture syndrome is an autoimmune disease in which lung and kidney
injury are caused by circulating autoantibodies against certain domains of type
IV collagen that are intrinsic to the basement membranes of renal glomeruli
and pulmonary alveoli giving rise to necrotizing hemorrhagic interstitial
pneumonitis and rapidly progressive glomerulonephritis.
 Clinical : mainly young men with hemoptysis followed by renal
disease
 Lungs are heavy, with areas of red-brown consolidation.
 lungs demonstrates focal necrosis of alveolar walls associated with
intra-alveolar hemorrhages, fibrous thickening of the septa, and
hypertrophy of septal lining cells.
 hemosiderin, either within macrophages or extracellularly
 Death from renal failure & restrictive lung disease

19. Continuous assessment
 A 69 years old male suffered from a pelvic
fracture. He was admitted to his local hospital and
remained bedridden for 6 weeks. Suddenly the
patient developed chest pain, collapsed and died.
What is the most probable diagnosis?
a. Lung tuberculosis.
b. Chronic venous congestion of the lung.
c. Pulmonary Saddle embolus.
d. Lobar pneumonia.