Chronic Venous Insufficiency (CVI) arises due to incompetence of vascular walls as
well as valves of the veins. This disorder leads reduction in blood flow to the heart resulting in
pooling of blood or stasis in the extremities especially the lower limbs. Patients with CVI usually
complain of pain and swelling in the limbs. Conversely, deep venous thrombosis (DVT) arises
when clotting occurs in the deep veins in the lower limbs (Patel & Brenner, 2013). Patients
suffering from DVT usually complain of pain as welling as swelling just as those with CVI. The
presentation of these conditions is almost similar. It is for this reason that health care providers
take extra caution when diagnosis CVI and DVT.
The Pathophysiological Presentation of DVT and CVI
The key pathophysiological difference between CVI and DVT is that DVT occurs in deep
veins whereas CVI occurs majorly in superficial veins. CVI affects popliteal, femoral, and
peroneal veins while DVT mail affects the soleal vein. Chronic Venous Insufficiency arises as a
result of damage of the endothelial walls and valves in the veins (Eberhardt & Raffetto, 2014).
Some of the common causes of CVI include pelvic tumors, DVI, and vascular malformations.
The valves of patients suffering from CVI are incompetent in that they cannot hold blood back
against the force of gravity. Consequently, blood pools in the lower extremities leading to
swelling especially in the ankles and the legs. Moreover, individuals with CVI present with
venous stasis ulcers, varicose veins, pain the feet, and itching and flaking of the skin. On the
other hand, DVT develops due to clotting in the veins. Severe clinical complications occur when
the formed clots lyse and get into the general circulation. Blood from deep veins usually flows
into the lungs. Therefore, when this blood carries clots with it, it may lodge them in the lungs
causing pulmonary embolism, one of the most severe result of DVT (Goldhaber & Bounameaux,
2012). Often CVI presents with dermatitis and ulceration due to the structural difference between
ANATOMY AND PHYSIOLOGY
the deep veins and superficial veins. That is, the superficial veins have an adipose layer and a
connective tissue whereas the deep veins have a fascia and muscles. This gives deep veins more
protection and structural support.
Venous and arterial thrombosis have a number of similarities although they differ in
terms of their pathophysiology, clinical interventions, and epidemiology. Venous thrombosis
occurs in undamaged parts of venous walls and in areas that have low sheer pressure. This
disorder leads to formation of red thrombi. Conversely, arterial thrombosis occurs in parts that
have high sheer stress and are rich in plaques. Unlike, venous thrombosis, arterial thrombosis
forms white thrombi.
The predisposition and pathophysiological advancement of DVT and CVI relies heavily
on the lifestyle of an individual. The pathophysiology of DVT and CVI is enhanced when a
person engages in activities that enhance the metabolic syndrome. Some of the most notable
practices that have been cited to predispose individuals to CVI and DVT include lack of physical
exercises, smoking, intake of meals rich in cholesterol, and psychosocial behavior (Csordas &
Bernhard, 2013). Smoking affects the circulation of blood and enhances blood clotting. On the
other hand, inactivity such as sitting for long periods causes calf muscles to contract hence
inhibiting proper circulation of blood. Lack of activity may also result in increase of weight
which then increases pressure in veins especially in the legs and the pelvis.
When diagnosing of CVI and DVT based on behavior, a physician should enquire the
social history of the patient. For instance, s/he can ask the patient whether s/he smokes or has
ever smoked. If the patient smokes, he should enquire when the patient started smoking and how
ANATOMY AND PHYSIOLOGY
many sticks he smokes in a day. Questions on whether the patient engages in physical exercises
such as jogging or long distance travelling are also essential in finding a differential diagnosis.
Clinical interventions for these patients involves the use of pharmacological as well as
non-pharmacological approaches. If the patient smokes, a physician should assess the
willingness of the patient to quit smoking. If s/he is willing to make a quit attempt, a brief
counselling session should be introduced, medications such as bupropion will be offered as well
as self-help resources. Follow-up visits should also be scheduled. The patient should also be
advised to engage in physical exercises such as jogging. The patient should also limit his/her
intake of cholesterol, leading factor in DVT development.
ANATOMY AND PHYSIOLOGY
Formation of blood clots
in deep veins, which may
then be transported by
blood to the lungs or the
Pain and swelling in
especially the ankles
MRI and CT
Recommendation of physical activity an
Causes about 1 out of
1000 deaths annually
with Europeans and
ANATOMY AND PHYSIOLOGY
Damage to endothelial
walls in veins and valves,
resulting in pooling of
blood leading to swelling,
pain, and varicose veins
Swelling of legs
Redding of skin around ankles
Leg UlcersCalf tightness
Varies from 1% to 40% in
women and 1% to 17% in men.
Prevalent in developed countries.
ANATOMY AND PHYSIOLOGY
Berkman, L. F., Kawachi, I., & Glymour, M. M. (Eds.). (2014). Social epidemiology. Oxford
Csordas, A., & Bernhard, D. (2013). The biology behind the atherothrombotic effects of cigarette
smoke. Nature Reviews Cardiology, 10(4), 219-230.
Eberhardt, R. T., & Raffetto, J. D. (2014). Chronic venous insufficiency.Circulation, 130(4),
Goldhaber, S. Z., & Bounameaux, H. (2012). Pulmonary embolism and deep vein
thrombosis. The Lancet, 379(9828), 1835-1846.
Patel, K., & Brenner, B. (2013). Deep venous thrombosis. Medscape reference.
Vascular and Endovascular Surgery Volume 38, Number 6, 2004
although the range included some values that
were above and below 1.5 to 2.0 control values.
These findings are similar to other studies that
have prospectively assessed DVT outcome with
serial duplex scanning and demonstrated a 30%/
19%,^ 38%’* and a 20%^ incidence of propagation
despite standard anticoagulation measures. No
particular vein segment that was originally in-
volved with thrombus had an increased likelihood
of propagation and the average length of time to
thrombus extension was 28 days, indicating this
process tends to occur early.
This would seem to imply that some patients
with lower extremity DVT can have extension of
their thrombi despite anticoagulation measures.
It seems likely that the effectiveness of anticoag-
ulation on thrombus varies, and factors that de-
termine efficacy of anticoagulant therapy are not
completely understood. However, the incidence
of recurrent venous thromboembolism is 15 times
greater in patients who are inadequately antico-
agulated for 24 hours or more during therapy
when compared to patients who are continuously
anticoagulated.’ When therapeutic, heparin pre-
vents extension of thrombi, accelerates clot orga-
nization and lysis,^°'” and decreases the incidence
of thromboembolism.^^ Yet venographically prov-
en DVTs have a 32% incidence of propagation on
repeat contrast study in the setting of adequate
anticoagulation.” Our data and the aforemen-
tioned prospective studies substantiate this same
finding with serial duplex scanning.
This raises the question of what is the clinical
implication of proximal extension of DVT in re-
gard to thromboembolism? The overall incidence
of high-probability V/Q scans in our patients with
lower extremity DVT assessed by repeat duplex
exam was 7.8%. Patients who had DVT extend
proximally had a significantly higher prevalence
of high-probability V/Q scans (13%) as compared
to those patients with thrombi that remained un-
changed, improved, or resolved (11%, 0%, and
3.7%, respectively). Furthermore, the difference
in pulmonary embolism among these 4 groups
could not be attributed to any difference in the
number of Greenfield filters inserted or the level
of anticoagulation. It may be that thrombi that
propagate are less stable and more likely to frag-
ment and cause pulmonary emboli.
The prevalence of pulmonary embolism was
determined by the number of high-probability
V/Q scans. Some controversy exists over the abil-
ity of V/Q scans to accurately diagnose pul-
monary emboli. The Prospective Investigation of
Pulmonary Embolism Diagnosis (PIOPED)^ as-
sessed the sensitivity and specificity of V/Q scans
by comparing 755 pulmonary angiograms to 931
V/Q scans in patients suspected of suffering from
PE. Eighty-eight percent of patients with high-
probability V/Q scans had angiographically prov-
en PE, whereas 33% of patients with intermedi-
ate-probability scans and 12% of patients with
low-probability V/Q scans had PE confirmed by
angiography. Although including only high-prob-
ability V/Q scans as a positive outcome sacrifices
some sensitivity, it gives the greatest positive pre-
dictive value. Furthermore, including intermedi-
ate-probability or even low-probability V/Q scans
to increase sensitivity of outcome would marked-
ly reduce specificity.
Given these data, the therapy for patients
who propagate lower extremity DVT has not been
established. Thrombol5^ic therapy is one alterna-
tive, but venous rethrombosis following treat-
ment of DVT with streptokinase has been report-
ed as high as 60%.^” An analysis of published es-
timates of the probabilities of various adverse
outcomes associated with treatment of DVT with
heparin verses heparin plus thrombolytic thera-
py found that patients treated with heparin alone
would have a slightly increased life expectancy. ^^
This brings into question the use of thrombolytic
therapy for proximal extension of DVT. A second
alternative would be insertion of a Greenfield fil-
ter. Risks and benefits of surgery must be
weighed against a 13% prevalence of PE in pa-
tients with propagating DVT. In 1 series examin-
ing extended indications for placement of an in-
ferior vena cava filter, ^^ no deaths were related
to filter insertion. A 4.5% wound complication
rate was found, and there was a 4.5% incidence
of pulmonary emboli following filter insertion,
which is similar to the 5% incidence commonly
reported by others.^^ Additionally, 98% caval pa-
tency has been found after filter insertion in long-
term follow-up.^^ A patient with marginal pul-
monary function who cannot sacrifice any pul-
monary reserve may be the ideal candidate for
insertion of an intracaval filter device when DVT
has been found to extend proximally.
Since this is a retrospective study, a certain
selection bias might exist for patients who under-
go repeat duplex ultrasound for lower extremity
DVT as compared to those patients who have only
a single exam for the same problem. Perhaps pa-
tients with persistently swollen extremities with
more pain and/or tenderness prompt physicians
to obtain repeated duplex exams to assess the
thrombus. Furthermore, persistently sjmiptomatic
DVT may be associated with more thromboem-
Ascher Repeat Duplex Ultrasound and Patient Management 5 3 1
bolic complications. Conversely, patients with
multiple duplex exams for DVT may be more
“health conscious” and wish to have repeated
exams to follow the outcome of their thrombus.
In order to account for such a selection bias, we
randomly selected 105 patients from the same
study period who had a single duplex exam
demonstrating lower extremity DVT and com-
pared them to patients with multiple duplex
exams for DVT. Although patients without follow-
up were older, there was no difference in antico-
agulation parameters, prevalence of intracaval fil-
ter insertion, or high-probability V/Q scans. These
findings tend to diminish selection bias favoring
either poor or improved outcome associated with
repeat duplex exams for lower extremity DVT,
further substantiating our findings.
In conclusion, repeat duplex ultrasound iden-
tifies proximal extension of lower extremity DVT,
which may be associated with an increased preva-
lence of high-probability V/Q scans. To detect this
propagation, we have suggested repeat duplex ul-
trasonography 1 week and 1 month after the ini-
tial diagnosis.^^’^^ Those patients with extension
of thrombus despite anticoagulation may benefit
from insertion of an intracaval filter device.
Prospective, multicenter trials are required to ob-
tain necessary numbers to further substantiate
- Meissner MH, Caps MT, Bergelin RO, et al: Propaga-
tion, rethrombosis and new thrombus formation after
acute deep venous thrombosis. J Vase Surg 22:558-
- Killewich LA, Bedford GR, Beach KW, et al: Sponta-
neous lysis of deep venous thrombi: Rate and out-
come. J Vase Surg 9:89-97, 1989.
- Murphy TP, Cronan JJ: Evolution of deep venous
thrombosis: A prospective evaluation with ultra-
sound. Radiology 177:543-548, 1990.
- Krupski WC, Bass A, Dilley RB, et al: Propagation of
deep venous thrombosis identified by duplex ultra-
sonography. J Vase Surg 12:467-475, 1990.
- Ramhorst B, Bemmelen PS, Hoeneveld H, et al:
Thrombus regression of spontaneous thrombolysis
with duplex scanning. Circulation 86:414-419, 1992.
- Johnson BF, Manzo RA, Bergelin RO, et al: Relation-
ship between changes in the deep venous system and
the development of the postthrombotic syndrome
after an acute episode of lower limb deep vein throm-
bosis: A one- to six-year follow-up. J Vase Surg 21:
- Markel A, Manzo RA, Bergelin RO, et al: Valvular re-
flux after deep vein thrombosis: Ineidence and time
of occurrence. J Vase Surg 15:377-384, 1992.
- Results of the Prospective Investigation of Pulmonary
Embolism Diagnosis (PIOPED). Value of the ventila-
tion/perfusion scan in acute pulmonary embolism.
JAMA 263:2753-2759, 1990.
- Salzman EW, Deykin D, Shapiro RM, et al: Manage-
ment of heparin therapy: Controlled prospective trial.
N Engl J Med 292:1046-1050, 1975.
- Bauer G: Clinical experiences of a surgeon in the use
of heparin. Am J Cardiol 14:29-35, 1964.
- Carey LC, Williams RD: Comparative effects of di-
coumarol, tromexan, and heparin on thrombus prop-
agation. Ann Surg 152:919-922, 1960.
- Coon WW, Willis PW III: Thromboembolic complica-
tions during anticoagulant therapy. Arch Surg
- Holm HA, Finnanger B, Hartmann A, et al: Heparin
treatment of deep venous thrombosis in 280 patients:
Symptoms related to dosage. Acta Med Seand 215:
- Dhall D, Dawson AA, Mavor GE: Problems of resis-
tant thrombolysis and early recurrent thrombosis in
streptokinase therapy. Surg Gyneeol Obstet 146:15-
- O’Meara JJ, MeNutt RA, Evans AT, et al: A deeision
analysis of streptokinase plus heparin as eompared
with heparin alone for deep-vein thrombosis. N Engl
J Med 330:1864-1890, 1994.
- Rohrer MJ, Seheider MG, Wheeler B, et al: Extended
indications for plaeement of an inferior vena cava fil-
ter. J Vase Surg 10:44-50, 1989.
- Greenfield LJ: Current indications for and results of
Greenfield filter placement. J Vase Surg 1:502-504,
- Berry RE, George JE, Shaver WA: Free-floating deep
venous thrombosis. A retrospective analysis. Ann
Surg 211:719-712, 1990.
- Lively SA, Devitt DT, Elder T, et al: Early Repetitive
duplex after diagnosis of deep venous thrombosis. J
Vase Teeh 26:278-280, 2002.
- Passman MA, Moneta GL, Taylor LM Jr, et al: Pul-
monary embolism is assoeiated with the eombination
of isolated calf vein thrombosis and respiratory symp-
toms. J Vase Surg 25:39-45, 1997.
- Wolf B, Nichols DM, Duncan JL: Safety of a single
duplex scan to exelude deep venous thrombosis. Br J
Surg 87:1525-1528, 2000.