Chapter 162 - SVC Occlusion and Management

Question 1

SVC occlusion cause breakdown into broad categories

Answer 1

60% malignant

40% benign

Question 2

Type of malignant causes of SVC occlusion

Answer 2

1) Non-small cell lung cancer 50%
2) SCLCa 22%
3) Lymphoma 12%
4) metastatic cancer 9%
5) germ cell cancer 3%
6) Thymoma 2%
Others: medullary + follicular Cancer of thyroid
teratoma
angiosarcoma
synovial cell cancer

Question 3

Benign causes of SVC obstruction

Answer 3

1) indwelling CVC and PM 7-33%
2) most common used to be mediastinal fibrosis and granulomatous fungal disease (histoplasmosis)
3) radiation
4) retrosternal goiter
5) aortic dissection

Question 4

SVC syndrome first described by

Answer 4

William Hunter 1757 with aortic aneurysm compressing SVC

Question 5

SVC syndrome found in this % with CVC and PM respectively

Answer 5

1-3% with CVC

0.2-3.3% with PM

Question 6

Risk of venous thrombosis increased by

Answer 6

1) thrombophilia (factor V leiden)

2) deficiency in anticoagulation factors: antithrombin III, protein S, protein C

Question 7

Symptoms of SVC syndrome

Answer 7

1) fullness in head/neck (number of pillows needed)
2) dyspnea
3) orthopnea
4) headache
5) dizziness
6) syncope
7) visual changes
8) confusion
9) cough

Question 8

Signs of SVC syndrome

Answer 8

1) dilated neck veins
2) swelling of face/neck/eyelids and UE
3) chest wall collateral veins
4) ecchymosis and cyanosis of face
malignancy can also cause:
5) hemoptysis
6) hoarseness
7) dysphagia
8) lethargy
9) weight loss
10) palpable cervical tumor or lymph nodes

Question 9

Diagnosis of SVC syndrome relies on:

Answer 9

clinical + CXR alone > 90% detected

Question 10

CXR signs of SVC syndrome

Answer 10

1) mediastinal widening
2) hilar mass right side
3) pleural effusion
4) bilateral diffuse infiltrates
5) upper lobe collapse
6) enlarged azygos
7) enlarged superior intercostal vein (aortic nipple) drains into the hemiazygous system

Question 11

Aortic nipple

Answer 11

enlarged superior intercostal vein

Question 12

Ultrasound in SVC syndrome

Answer 12

only indirect detection

lack of respiratory variations

Question 13

Radionuclide imaging in SVC syndrome pro and con

Answer 13

Tc 99m inject to bilateral arms
Pro: functional aspect, collateral pathway, use in F/U to detect changes
Con: low resolution, cannot identify cause

Question 14

CTA in SVC syndrome

Answer 14

1) identifies mass
2) identifies CVC, PM presence
3) defines collateral pathway
4) differentiate benign vs malignant causes

Question 15

Collateral pathways in SVC syndrome

Answer 15

1) azygous-hemiazygous pathway
2) internal mammary pathway
3) lateral thoracic-thoracoepigastric pathway
4) vertebral pathway + small mediastinal veins
5) hepatic parenchyma and pulmonary pathway

Question 16

Venography in SVC syndrome

Answer 16

Gold standard

1) anatomic roadmap
2) presence, direction of collateral flow

Question 17

Types of SVC syndrome

Answer 17

Type 1: partial obstruction
Type 2: complete/near complete obstruction, antegrade azygous
Type 3: complete/near complete obstruction, retrograde azygous
Type 4: IVC drainage only, incomplete azygous/hemiazygous system

Question 18

MRV in SVC syndrome

Answer 18

non-invasive without iodinated contrast use but cannot do in some PM
risk of NSF

Question 19

Initial management of SVC syndrome

Answer 19

1) elevate head
2) behavioural modification
3) LMWH + LT A.C.
4) thrombolysis if benign
5) radiation and chemo if malignant

Question 20

Ratio of malignant cause of SVC syndrome non-responsive to radiation or chemo

Answer 20

1/4

Question 21

Candidates for types of malignancy for surgery resection

Answer 21

1) lymphoma
2) thymoma
3) metastatic medullary carcinoma of thyroid

Question 22

First endo for SVC done by

Answer 22

Sherry 1986; cause was a PM wire

Question 23

Stents used in SVC syndrome (uncovered)

Answer 23

1) Gianturco Z (self-expand) with large stent interstices (risk tumor ingrowth)
2) palmaz: short and precise but poor flexibility
3) wallstent
4) smart stent
5) protege stent
6) E luminexx
7) sinus XL
9) Zilver vena

Question 24

Perforation of SVC in POBA treatment

Answer 24

1) prolonged inflation

2) covered stent

Question 25

Surgery options for SVC obstruction

Answer 25

1) GSV connect EJV/IJV to FV with 2 GSV segment with PTFE protection outside
2) spiral GSV (described by Chiu and Doty)
3) FV but risk LE edema in this population
4) PTFE need fistula if poor inflow like subclavian; ringed enforced
5) spiral bovine
6) cryograft
7) patch only if tumor partial

Question 26

Chiu equation

Answer 26

l = RL/r

r and l for GSV
R and L for eventual graft

typically one GSV from thigh to knee gives 10 cm graft

Question 27

Surgical exposure for SVC operation

Answer 27

1) Median sternotomy extending to IJ on medial SCM
2) enter mediastinum and resect tumour
3) enter pericardial sac
4) right atrial appendage or SVC as outflow
5) unilateral enough because of face + neck collaterals

Question 28

Current surgical algorithm in SVC treatment

Answer 28

1) endo first
2) similar endo and sx patency
3) covered stent better than uncovered
4) vein better than PTFE

Question 29

Graft restenosis key points in SVC obstruction

Answer 29

most within 1-2 years

always with symptom recurrence