DEEP VEIN THROMBOSIS

1) Review of the Evidence on Diagnosis of Deep Venous
Thrombosis and Pulmonary Embolism
2) Duration of anticoagulant therapy after a first episode of
an unprovoked pulmonary embolus or deep vein
thrombosis
Speaker : Dr. Vinaykumar

Venous system of Lower
Limbs
 The veins of the lower extremities are divided
into three systems:
 Superficial
 Deep
 Perforating
 These are located in two
main compartments:
 Superficial
 Deep

Introduction
Deep vein thrombosis and pulmonary
embolism constitute venous thromboembolism.
DVT occurs most often in the legs, but can form in
the veins of the arms and in the mesenteric and
cerebral veins.
Pulmonary embolism is the third most
common cause of mortality by cardiovascular
disease after coronary artery disease and stroke.

Epidemiology
 The incidence of first DVT is 0·5 per 1000
person-years & PE 0.69/1000 person yrs.
 The disorder is rare in children younger than 15
years, but its frequency increases with age.
 Two-thirds of first-time episodes of deep vein
thrombosis are caused by risk factors, including
surgery, cancer, immobilization or admission for
other reasons.

 Risk for first DVT seems to be slightly higher in
men (1.3:1.1::male:female per 1000 person-
years)
 The risk for recurrence of this disorder is higher
in men than in women

Risk factors for DVT & PE
Idiopathic, primary, and
unprovoked
Secondary and
provoked
• No apparent cause
• Old age (>65 years)
• Long distance travel
• Associated with
thrombophilia (eg, factor V
Leiden or prothrombin
gene mutation)
• Obesity
• Cigarette smoking
• Hypertension
• Immobilisation
• Postoperative
• Trauma
• Oral contraceptives,
pregnancy,
postmenopausal HRT
• Cancer
• Acute medical illness
(eg, pneumonia,
congestive
heart failure)

Surgery
 Thrombotic risk depends on the type of surgery
and presence of additional risk factors.
 The approximate risk for DVT following general
surgery procedures is 15 - 40%.
 Risk nearly doubles after hip or knee
replacement surgery or hip fracture surgery by
40 -60%
 High risk surgeries : Orthopaedic, major
vascular and neurosurgery.

Trauma
 Risk for thrombosis is high in patients with
spinal injuries, pelvic fractures, or leg
fractures
• In patients with first spontaneous DVT, the
annual likelihood of recurrence is 5–15%.
• Risk is low in patients with postoperative
deep vein thrombosis.
History of deep vein thrombosis

Cancer
 Cancer patients who undergo surgical
treatment or chemotherapy have a high risk of
VTE.
 Tumors of the bone,ovary, brain, and pancreas
are associated with the highest incidence of
VTE
 Treatment of VTE in cancer patients is
challenging because of high rates of anti-
coagulant associated bleeding and treatment
failures.

Travel
 Traveling in general found to increase the risk of
VTE by 2-fold
 The risk of flying is similar to the risks of traveling
by car, bus, or train.
 The risk is highest in the first week after traveling,
 High relative risk of VTE in individuals with factor
V Leiden, BMI > 30 kg/m2, Tall, OCPs,
 Even short people has increased risk of VTE
after air travel.

Paediatric DVT
 Deep venous thrombosis in children is
frequently related to central venous
lines.
 The frequency of pediatric DVT related
to CVL is 11-50%
 Typical symptoms of thrombosis are
frequently absent.

Pregnancy
 Pregnant women have a much higher
risk of VTE
 Risk is higher after caesarian section
than after vaginal delivery.
 The incidence appears to be highest in
the postpartum period.

Thrombophilia
 Several distinct abnormalities in the coagulation
system are associated with increased risk for
DVT.
 These defects are generally inherited and
detected with first spontaneous thrombosis.

Antibodies against
phospholipids
 Antibodies against phospholipids (lupus
anticoagulant), cardiolipin or glycoprotein
interact with phospholipids or plasma proteins
bound to an anionic surface.
 The prevalence in unselected patients with DVT
is about 5%.
 The lupus anticoagulant confers a tenfold
increased risk for first thrombosis and is a risk
factor for recurrence,

Natural inhibitor deficiencies
 Antithrombin III is a potent inhibitor of several
coagulation proteases. The frequency of antithrombin
deficiency <1% in unselected patients with VTE.
 Protein C is a vit K-dependent glycoprotein, the frequency
of deficiency is 3·2% of unselected patients with VTE.
 Protein S is a vit K-dependent glycoprotein and a cofactor
for protein C. This deficiency was reported in 7·3% of
unselected patients with DVT.
Deficiency confers >8 fold increased risk for DVT

High clotting factor levels
 Raised concentration of factor VIII, IX, factor XI
is an independent risk factor of first spontaneous
DVT.
 The mechanisms of thrombosis is unclear.
 High factor VIII is a potent risk factor for
recurrence of DVT.

CLINICAL PROBABILITY
SCORING SYSTEM

Wells score for DVT Score
Cancer +1
Paralysis or recent plaster cast +1
Bed rest >3 days or surgery <4 weeks +1
Pain on palpation of deep veins +1
Swelling of entire leg +1
Diameter difference on affected calf >3 cm +1
Pitting oedema (affected side only) +1
Dilated superficial veins (affected side) +1
Alternative diagnosis at least as probable as DVT –2

Patients with a score of
0 : low risk,
1–2 : intermediate risk,
≥3 : high risk

Wells score for PE Score
Previous PE or DVT +1・5
Heart rate >100 beats per min +1・5
Recent surgery or immobilisation +1・5
Clinical signs of DVT +3
Alternative diagnosis less likely than PE +3
Haemoptysis +1
Cancer +1

For the initial rule, patients with a score of
0–1 : low risk
2–6 : intermediate risk
≥7 : high risk;
For the dichotomised rule,
 score ≥4 likely to have PE
 score≤4, unlikely to have PE

Revised Geneva score for PE Score
Age >65 years +1
Previous DVT or PE +3
Surgery (under general anaesthesia) or fracture (of the lower limbs) within 1
month
+2
Active malignancy (currently active or considered as cured since less than 1
year)
+2
Unilateral leg pain +3
Haemoptysis +2
Heart rate 75–94 beats per min +3
Heart rate ≥95 beats per min +5
Pain on deep vein palpation in leg and unilateral oedema +4

Patients with a score
<2 : low risk,
2–6 : intermediate risk,
≥6 : high risk.

Clinical features of DVT
 Localised tenderness
 Swollen leg
 Calf swelling 3 cm greater than asymptomatic
leg
 Pitting oedema
 Collateral superficial veins (non-varicose)

Clinical features of Pulmonary Embolism
The symptoms and signs of PE are not specific.
Severe cases of PE can lead to collapse or
sudden death.
In the majority of the fatal cases
the PE is not clinically diagnosed
prior to death.

Symptoms include:
 Dyspnoea.
 Pleuritic chest pain, retrosternal chest
pain.
 Cough and haemoptysis.
 In severe cases, right heart failure
causes dizziness or syncope.

Signs include:
 Tachypnoea, tachycardia.
 Hypoxia, which may cause anxiety,
restlessness, agitation and impaired
consciousness.
 Pyrexia.
 Elevated jugular venous pressure.
 Systemic hypotension and cardiogenic shock.

Fibrin D-Dimer measurement
 Plasma D-Dimer is a degradation product of
cross linked fibrin and its levels increase in
plasma of patients with acute VTE.
 DD assay is highly sensitive (>98%)
in acute DVT or PE
(cutoff value of 500 mg/l)
Hence, a DD level below
this value reasonably
rules out acute VTE.

 Sensitivity is very high but specificity of fibrin
for VTE is poor, because fibrin is produced in
a wide variety of conditions such as cancer,
inflammation, infection or necrosis.
 D-Dimer >500 mg/l has a poor positive
predictive value for VTE. So it must be
combined with clinical probability in order to
safely rule out VTE.

Venography
was considered the diagnostic standard
for diagnosing DVT but it is invasive, costly
and not devoid of risk. It is still used as
surrogate end point in thrombo
prophylactic trials.

Although gold standard for diagnosing PE,
pulmonary angiography is difficult to
interpret, frequent disagreement occurring
even between expert readers, more often on
the absence (17%) than on the presence of
PE (8%).
Pulmonary angiography

Compression ultrasonography (CUS)
 Lower limb compression venous USG, a
noninvasive test with sensitivity of 97% &
specificity of 98% for symptomatic proximal DVT.

 The single well-validated diagnostic
criterion for DVT on CUS is absence of full
compressibility of the deep vein when
applying pressure through the ultrasound
probe.

Ventilation/perfusion lung scintigraphy
 Perfusion lung scintigraphy is a noninvasive technique
allowing the visualisation of pulmonary perfusion
through IV albumin macroaggregates labelled by
technetium 99. These are trapped in pulmonary
capillary vessels and imaged by a gamma camera.
 Pulmonary hypo-perfusion is not highly specific for an
embolus, since any disease that narrows the airways or
fills the alveoli with fluid will result in hypoxic pulmonary
vasoconstriction.

 A perfusion defect corresponding to a segment or a
large part of a segment is more specific for PE.
 The addition of ventilation scintigraphy(by xenon 133,
krypton 81 or aerosolised technetium 99)
further increases specificity, a so-called mismatched
defect (perfusion defect with normal ventilation)
representing
PE.

 lung scan results are classified into three
categories: normal, high probability and
non diagnostic
 Attribution of a lung scintigram to the high-
probability category requires two or more
mismatched segmental defects or, if only
one is present, the addition of two large
mismatched sub segmental defects

Spiral CT scan
 Spiral CT scanning allows an adequate visualisation
of the pulmonary arteries up to segmental level. With
sensitivity 70% & specificity of 90%..

 Multi-detector CT is highly sensitive, which allows
both a thinner collimation (1–2mm collimation)
and a better definition of the picture.
 CT angio has largely replaced ventilation
perfusion scan as main imaging modality in PE
 The probability of PE is very low in patients with a
low or intermediate clinical probability, absence of
proximal DVT and a negative spiral CT.

Echocardiography
 Doppler echocardiography is not a diagnostic tool,
but in suspected PE it may play a role in risk
stratification.
 In 4% of patients, transthoracic echo allows direct
visualisation of the clot in the right heart chambers or
in the right main pulmonary artery.

 Echocardiographic manifestations of PE are
acute increase in pulmonary arterial resistance
and pulmonary hypertension.
 Signs : dilation of the right ventricle, hypokinesis,
and in severe cases, paradoxical motion of the
interventricular septum.
 In patients with shock, it is extremely effective
for differential diagnosis with tamponade and
cardiogenic shock.

Magnetic Resonance Venous Imaging
(MRVI)
 Help in the imaging of more proximal venous
disease.
 Useful test for imaging iliac veins, IVC, calf
vein & recurrent DVT and area where the use
of duplex ultrasound is limited.

Massive PE
 In highly unstable patients start thrombolytic
treatment.
 If patient is temporarily stabilised by
vasopressive drugs, diagnosis is confirmed by
either lung scan or spiral CT.

Recurrent deep vein thrombosis
 Clinical assessment of recurrent ipsilateral DVT
is hampered by the similarity between symptoms
of post-thrombotic syndrome and acute DVT.
 Use of ultrasonography is limited because
abnormalities in the proximal veins and
comparison with previous USG results needed.

 Diagnosis of recurrent DVT requires the
detection of a new non-compressible segment
by USG.
 If the result is nondiagnostic or negative, with
high clinical probability, venography should be
done.

Chronic thromboembolic pulmonary
hypertension
 Defined as a mean pulmonary artery pressure
greater than 25 mm Hg that persists 6 months
after diagnosis of pulmonary embolism.
 The disorder occurs in 2–4% of patients after
acute pulmonary embolism and results in
disabling dyspnoea, both at rest and with
exertion.

Post-thrombotic syndrome of the leg
 Post-thrombotic syndrome of the leg arises in
20-50% of patients with first proximal DVT who
has received standard treatment with
anticoagulants.
 PTS include chronic calf swelling with brownish
skin pigmentation and in extreme
circumstances venous ulceration of the skin.

 Risk factors are recurrence in the ipsilateral
leg and possibly proximal thrombosis.
 In most people, the disorder arises within 2
years.

Deep vein thrombosis of the arms
 Symptoms include pain, oedema, and cyanosis.
 Deep vein thrombosis of the arms arises as a
complication of central venous catheters, or
idiopathic (0·02 /1000 people per year)

 On clinical suspicion, compression CUS is the
preferred diagnostic method.
 If USG is inconclusive or negative despite a
high clinical probability, venography should be
done.

Treatment
Initial treatment
 Fixed-dose, weight adjusted, subcutaneous
LMWH is treatment of choice.
 Dose, 1mg/kg body weight twice daily or 2mg/kg
body weight once daily.
 Because of its shorter half-life, unfractionated
heparin might be used in surgical patients with
DVT in whom rapid reversal of anticoagulation is
necessary.

Thrombolytic therapy
 It should be reserved for patients with limb-
threatening thrombosis
 Given either systemically or via local catheter-
directed infusion.

Vena cava filters
 In patients with proximal DVT
 Vena cava filters are thrombogenic and double the
recurrence risk. They used selectively in patients
with
 contraindications to anticoagulants,
 recurrent PE despite adequate
anticoagulation,
 chronic thromboembolic pulmonary
hypertension.

Endovascular
reconstruction
 Recanalisation of occluded iliac vein is
performed endovascularly.
 Balloon dilatation is then performed and
stent is placed across the dilated
segment.
 This is the first line therapy for iliac vein
occlusions.

Long-term prevention
 vitamin K antagonists started simultaneously with
heparin (same day)
 The dose is titrated to achieve INR between 2-3.
 Heparin can be discontinued after 5–7 days, as
long as the ratio is stable and is 2·0 or greater.

Ann Fam Med 2007;5:63-73.
Topic 1

 This journal summarizes the evidence
regarding the efficacy of techniques for
diagnosis of deep venous thrombosis (DVT)
and pulmonary embolism.

INTRODUCTION
 The incidence of isolated DVT is around
50 per 100,000 person-years
 30% of patients with DVT develop
symptomatic PE and another 40% have
asymptomatic PE.

Article Review Process and Data
Abstraction
 They reviewed 22 systematic reviews and 36
primary studies.

Result
 Results provide strong evidence to support
the use of a clinical prediction rule for
establishing the pretest probability of disease
in a patient before more definitive testing.
 Use of a D-dimer assay with a clinical
prediction rule has a very high negative
predictive value.

 The Wells prediction rule was most frequently
evaluated in these studies
Pretest probability for DVT Prevalence
High 17 - 85%.
Moderate 0 - 38%
Low 0 - 13%.

Wells prediction rule evaluated for pulmonary
embolism
Pretest probability for PE Prevalence
High 38 - 78%.
Moderate 16 - 28%
Low 1 - 3%.
Geneva prediction rule evaluated for pulmonary embolism
Pretest probability Prevalence
High 77 – 85%
Moderate 34 -35%
Low 7%

Clinical prediction rule with a D-dimer assay.
Result of studies
D-dimer assay & pretest probability 3-month incidence of VTE
-ve DD + low PTP 0.5%
-ve DD + moderate PTP 3.5%
-ve DD + high PTP 21.4%

 Studies evaluating enzyme-linked
immunosorbent assays (ELISA) and latex
turbidimetric assays for diagnosis of PE.
 D-dimer cutoff of was 500 ng/mL.
Sensitivity Specificity
ELISA assays 95% 45%
Latex
turbidimetric assay
93% 51%

 It is concluded that both tests are highly
sensitive and clinically useful in excluding
disease with low to moderate clinical probability
of pulmonary embolism.

D-dimer assay in patients
with symptoms of lower
extremity DVT
Results
 In many studies sensitivity of the assay was
<90%, making it insufficiently sensitive to “rule
out” a diagnosis of DVT.
 The performance of the assays was affected by
the relevance of DVT in the population and the
choice of reference test.
 More sensitive for diagnosing thrombus above
the knee than for diagnosing calf-vein
thrombosis.

D-dimer assays used for either DVT or PE
diagnosis
 Authors included all types of D-dimer assays.
 The pooled sensitivities and specificities
were highest for ELISA and Quantitative
rapid ELISA
DVT PE
ELISA 95% 96% 40 - 50%
Quantitative rapid
ELISA
96% 97% 40 - 50%

 The authors concluded that the negative
predictive values for ELISA assays, are
sufficiently high that these assays should be
able to stand alone in excluding a diagnosis of
DVT or PE.

 Studies that summarized the accuracy of
USG (with or without color Doppler) for the
diagnosis of DVT using contrast venography
as the reference standard.
 The reviews included studies of
symptomatics, asymptomatic patients or
both.
 Studies to detect thrombosis of the proximal
veins, distal veins or both.

Result
 USG has high sensitivity and specificity for
diagnosing proximal DVT.
 In high-risk asymptomatic patients (Post-op)
specificity is high but sensitivity may be
diminished;
 Sensitivity for detecting calf vein thrombosis
is poor.

 For the diagnosis of symptomatic
thrombosis in the proximal veins, the reviews
reported sensitivities of 89 - 96% and
specificities 94 - 99%.
 For detection of asymptomatic thrombi in
proximal veins, the reviews suggested that
high specificity but low sensitivity.

Symptomatic
calf vein
thrombosis
gottlieb et al 93% 99%
Other reviews 73-75%
Asymptomatic calf vein thrombosis Around 50%
Symptomatic upper extremities 56 -100% 77 -100%

 10 systematic reviews summarizing the
accuracy of helical CT for the diagnosis
of pulmonary Embolism shows,
Helical CT 66 -93% 89 -98%

 9 prospective studies with pulmonary
arteriography as the reference standard.
 Only 4/9 studies reported sensitivity >90%
 6/9 studies reported specificity >90%.
45 -100% 78 -100%

 The published literature has not kept up
with advances in CT technology (high-
resolution multidetector CT)
 Only 1 study showed the accuracy of Multi
detector CT angio which reported a
sensitivity of 100%.

Clinical assessment with Multidetector CT
angiography
High Intermediate Low
Positive predictive
value
96% 92%
Negative predictive
value
96%

In review of 25 studies, 2 strategies were highly
effective in excluding pulmonary embolism
(1) Normal results on pulmonary angiography or
lung scintigraphy
(2) Normal D-dimer with low clinical probability.

CONCLUSION
 The evidence strongly supports the use of
clinical prediction rules for establishing the
pretest probability of DVT or PE in a patient
before more definitive testing.
 D-dimer assay with a clinical prediction rule
has a high negative predictive value.

 D-dimer, in isolation also has strong negative
predictive values for detection of DVT and
PE.
 USG is a good testing modality for
diagnosing proximal VTE in symptomatic
patients, but it is less accurate in distal veins,
upper extremity veins, and in asymptomatic
patients.

 Multidetector CT has high sensitivity and
positive predictive value for diagnosing PE.
 Multidetector CT becoming the norm in many
hospitals for diagnosing PE.

Topic 2
Duration of anticoagulant therapy after a
first episode of an unprovoked
pulmonary embolus or deep vein
thrombosis: guidance from the ISTH
Journal of Thrombosis and Haemostasis, 10: 698–702

Scope and methodology
 Unprovoked PE and DVT are defined as those
occurring in the absence of an antecedent
(within 3 months) surgical or nonsurgical risk
factor.
 Account for 25% to 50% of all patients with
VTE.

Definition of terms
The definitions of duration of anticoagulation are:
1 Initial anticoagulation: 3–6 months of treatment;
2 Long-term (indefinite) anticoagulation: > 3–6
months of treatment with no definite stop time
which could be either lifelong or until the
perceived bleeding risk precludes continuation
of anticoagulation.

PE and Lower limb DVT
 A period of adequate vitamin K antagonist (VKA)
anticoagulation with a target INR of 2.5 (range 2–
3) is required to prevent extension of thrombus
and prevent early recurrence (within the first 3-6
months). Long-term anticoagulation is required to
prevent late recurrence.
 The benefit of anticoagulation continues only for
as long as therapy is continued.

Duration of initial anticoagulation
 Patients with unprovoked isolated distal (calf
vein) DVT have a risk of recurrence that is
about half that of a proximal DVT or PE and
the recurrence rate after 3 months of
anticoagulation appears to be lower than with
shorter duration treatment.
 At least 3 months of anticoagulant therapy is
required to prevent extension of thrombus and
prevent early recurrence after a first PE and/or
proximal DVT.

 However, 6 months of initial anticoagulation of
patients with unprovoked PE or proximal DVT
appears to offer a lower risk of early recurrence
than 3 months of treatment.

Guidance statements
1 Patients with an unprovoked calf DVT should
be treated for 3 months.
2 Patients with an unprovoked PE or proximal
DVT should be treated for 3 to 6 months.

Continued anticoagulation beyond
the initial 3-6 month period
 Patients with unprovoked venous thrombosis
have an annual risk of recurrence > 5%, this risk
exceeds the risk of VKA-related bleeding,
 Patients with a first or recurrent episode of
unprovoked PE or proximal DVT should be
considered for long-term anticoagulation.

 They should be treated initially with 3 months
anticoagulant therapy and then considered for
long-term (potentially lifelong) anticoagulation
depending on their risk of bleeding.
 Patients with a PE and DVT provoked by surgery
are at low risk of recurrence (annual risk< 1%)
after completion of 3-months oral anticoagulants,
so longer therapy is not routinely required.

 PE or DVT associated with non-surgical
risk factors have a variable risk of
recurrence, The duration of anticoagulation
should be influenced by the perceived risk
in individual patients.
 Long-term anticoagulant therapy generally
be reserved for patients with no identifiable
antecedent risk factor.

Guidance statements
1 For Unprovoked calf DVT, anticoagulant therapy for
longer than 3 months is not required.
2 Unprovoked PE or proximal DVT anticoagulation
should be considered for as long as the perceived risk
of anticoagulant-related bleeding is not so high as to
preclude continued treatment.
3 Patients with a provoked PE and DVT anticoagulant
therapy after 3 months is not required.

Hormone-associated PE and DVT
 Defined as a PE/DVT occurring in women who
are receiving estrogen-containing hormonal
therapy (OCP / HRT) and do not have additional
risk factors.
 Prognosis is generally good.
 Approximately 50% lower risk for thrombosis
recurrence compared with women with an
unprovoked VTE occurring in the absence of
hormonal use.

 These Women are advised to stop this
preparation.
 Patients with strong gynecological indications
or a personal preference for hormonal
treatment are combined with continued
anticoagulant therapy.

Guidance statements
1 Women with a hormone associated VTE if hormone
therapy is stopped at the time of diagnosis,
anticoagulants are given for 3 months.
2 In premenopausal women an effective alternative
contraception must be utilized to avoid the potential
toxicity of early fetal warfarin exposure.
3 Hormonal therapy can be continued in selected patients
if there is a strong clinical indication but anticoagulant
therapy should be continued for the duration of
hormonal therapy.

Risk of bleeding and quality of
anticoagulant therapy
Major determinants of bleeding as a result of VKA
therapy include:
(i) Advanced age;
(ii) Previous bleeding;
(iii) Increased (or variable) intensity of anticoagulation;
(iv) Comorbidities such as renal or hepatic impairment
(v) Concomitant use of drugs that affect hemostasis,
(aspirin / clopidogrel)
(vi) Duration of therapy.

Factors to predict risk of recurrence
D-dimer
 Individual risk of recurrence is
heterogeneous.
 Lower annual risk in patients with a low D-
dimer(~4%) result after completion of
initial VKA therapy compared with those
with a high D-dimer (~9%).

Residual vein occlusion
 Residual vein occlusion, as detected by venous
ultrasound, does not predict a likelihood of a
recurrent DVT to a degree that is clinically useful.
Post-thrombotic Syndrome
 Post-thrombotic syndrome (PTS) is associated with
a 2.6 fold increased risk of recurrence after
unprovoked DVT.
 PTS is associated with a high D-dimer.

Thrombophilia
 Testing for heritable thrombophilic defects
does not usefully predict likelihood of
thrombosis recurrence after a first episode of
VTE.
Male Gender
 Males appear to be at 1.8-fold higher risk of
recurrence after an episode of an unprovoked
VTE.

Mode of clinical presentation
 Patients with an initial unprovoked PE are 3-4
times more likely to suffer recurrence as a PE
rather than DVT.
 And the risk of a fatal PE is 2-4 times more
likely in patients with a symptomatic PE as
compared with patients with a symptomatic
DVT alone.

Guidance statements
1) It is not possible to give a definitive guidance
statement as to which patients should or
should not receive long-term anticoagulant
therapy after an episode of an unprovoked PE
or DVT.
Patients should be assessed on an
individual basis, taking into consideration
factors contributing to thrombosis recurrence
risk and bleeding risk.

2 ) Following factors may favor long-term
anticoagulation in patients with a first
unprovoked PE or DVT:
a. Male gender;
b. Moderate-to-severe post-thrombotic syndrome;
c. Ongoing dyspnoea (possibly related to
unresolved or recurrent PE);
d. Satisfactory initial anticoagulant control;
e. Elevated D-dimer result.

3) Following factors may favor stopping
anticoagulation in patients with a first
unprovoked VTE:
a. Female gender;
b. Absent or mild post-thrombotic syndrome;
c. Unsatisfactory initial anticoagulant control;
d. Low D-dimer result.

Upper limb DVT
Initial anticoagulant therapy for upper limb VTE is
the same as for the lower limb.
Most cases of an upper limb DVT are provoked
by central venous catheters.

Long-term anticoaulant therapy is not routinely
required even if DVT is unprovoked as the
recurrence rate appears to be low(<5%).
Risk factors that may indicate consideration of
continued anticoagulation
 Persistent thoracic outlet syndrome,
 Severe post-thrombotic syndrome
 The continued use of an indwelling central venous
catheter.
Vascular surgical intervention can be undertaken for
severe thoracic outlet syndrome.

Guidance statements
 Unprovoked upper limb DVT should be
treated for 3 months initially.
 Long-term anticoagulant therapy is not
routinely indicated in the absence of
continuing risk factors(central venous
catheter, persistent thoracic outlet syndrome
or severe post thrombotic syndrome)

DEEP VEIN THROMBOSIS

Recomendados

Recomendados

Más contenido relacionado

La actualidad más candente

La actualidad más candente (20)

Destacado

Destacado (20)

Similar a DEEP VEIN THROMBOSIS

Similar a DEEP VEIN THROMBOSIS (20)

Último

Último (20)

DEEP VEIN THROMBOSIS