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concave leaﬂ ets facing upward. Weight of blood

coming backward onto the concavity of the leaf-

lets ﬁ lls them and causes them to fall backward.

This prevents further ﬂ ow and maintains the

competence of the valve.

Tributaries of GSV [ 1 ]

(a) Near termination : The conﬂ uence of superﬁ -

cial inguinal veins – formed by superﬁ cial cir-

cumﬂ ex iliac vein, superﬁ cial epigastric and

external pudendal veins, and the distal GSV.

(b) At the thigh : Anterior accessory and poste-

rior accessory GSV of the thigh.

accessory GSV of the leg. The posterior

accessory GSV of the leg was known as pos-

terior arch vein or Leonardo’s vein.

The accessory veins lie at a slightly anterior

plane compared to the GSV outside the saphe-

nous compartment. At the saphenofemoral junc-

tion, there could be a variable number of other

unnamed tributaries [

7 ].

Saphenous Nerve and Its Relation

to the GSV

Saphenous nerve is the largest branch of the fem-

oral nerve and is a purely sensory nerve. It

descends along with the femoral artery. It exits

the adductor canal at its distal end, pierces the

fascia lata, and becomes subcutaneous. In

the lower part of the leg, it is in close proximity to

the GSV. The nerve can be damaged during surgi-

cal stripping and endovenous procedures. The

damage is less likely at the upper part of the leg

because of the larger gap between the nerve and

vein here.

Short Saphenous Vein (SSV)

The SSV originates from the lateral side of the

foot and drains into the popliteal vein. The fol-

lowing anatomical facts are important in surgery

of SSV:

(a) The SSV pierces the deep fascia of the leg at

the mid calf level and runs between the two

heads of the gastrocnemius to enter the popli-

teal vein. The upper one-third of the SSV lies

below the deep fascia [

8 , 9 ]. Hence, the deep

fascia of the popliteal fossa has to be incised

to expose the terminal portion of the SSV.

(b) The termination of the SSV can be variable.

Three types of terminations have been

described – Kosinski’s variations [ 8 , 9 ].

• Normal termination (57 %) – enters the

popliteal vein in the popliteal fossa

Superficial external

pudendal vein

Posterior accessory

vein

Gsv

Femoral

vein

Anterior accessory

vein

Superficial external

iliac vein

Superficial

epigastric

vein

External pudendal

artery crossing

inferiorly at fossa

ovalis

Fig. 2.1 ( a , b ) SFJ anatomy

Anatomy of Lower Limb Venous System

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• High termination (33 %) – ends in the mid

thigh in a muscular vein or the GSV

• Low termination (10 %) – ends in the

deep veins of the calf or deep sural mus-

cular veins or GSV in the upper third of

the leg

distal part of the calf. In a study on the fascial

anatomy of SSV of 20 embalmed human

specimens, it has been reported that the dis-

tance between the SSV and the sural nerve

was less than 5 mm in proximal 1/3 of the

lower leg in 70 % of specimens; the deep fas-

cia was present between the SSV and the

sural nerve in more than 95 %. In the distal

2/3 of lower leg, the distance between the

SSV and the sural nerve was less than 5 mm

in 90 % and the deep fascia was present

between the two structures in only 15 %.

Hence, the sural nerve is at risk of thermal

injuries during endovenous thermal ablation

in the lower leg [ 10 ].

(d) The vein of Giacomini (intersaphenous vein)

runs in the posterior part of the thigh and

connects the SSV with the GSV. A SSV pro-

jection or tributary ascending in the thigh

above 12 cm from the popliteal skin crease is

designated as the Giacomini vein irrespective

of the termination of the SSV (Fig. 7.6b ). It is

reported in 70.4 % of limbs. In the lower

thigh, it is located below the deep fascia. In

the middle and upper thigh, it perforates the

deep fascia and ends in the superﬁ cial or

deep veins or in the muscular veins. Its pres-

ence does not affect the position of SSV

termination; nor does it affect the severity of

venous disease [

11 , 12 ] .

Deep Veins

More than 80 % of the blood ﬂ ow in the lower

limbs is through the deep veins. The deep veins

of the lower extremity accompany the arteries

and their branches. They possess numerous

valves.

In the leg , these include the posterior tibial

veins, anterior tibial veins, and peroneal veins.

They are all paired structures. In the thigh , these

include the popliteal vein, femoral vein, profunda

vein, and the common femoral veins.

The pelvic veins include the external iliac,

internal iliac, and common iliac veins and the

inferior vena cava. The gonadal veins draining to

IVC on right side and the renal vein on the left

side are important vessels in the pathogenesis of

pelvic congestion syndrome (PCS).

Perforating Veins [ 2 , 6 ]

These veins perforate the muscular fascia to con-

nect the superﬁ cial veins with the deep veins.

Communicating veins connect veins within the

same system [ 3 ]. There are as many as 150 perfo-

rating veins in the lower extremity, although only

a few of these are clinically important [ 13 , 14 ].

The medial calf perforators are probably the most

important from the clinical point of view. Most

perforators are inactive in the normal state. In the

presence of venous hypertension, they open up

and reﬂ ux blood to superﬁ cial veins.

Perforators in the foot : These consist of the

dorsal, plantar, medial, and lateral perforators.

Between the ﬁ rst and second metatarsal bones, a

large perforating vein, connecting the superﬁ cial

venous arch to the pedal vein, can be identiﬁ ed.

Perforators at the ankle : These are a cluster of

vessels arranged as anterior, medial, and lateral

groups.

Medial calf perforators : They are arranged in

two groups:

(a) Posterior tibial perforating veins : They were

known as the Cockett perforators. They con-

nect the posterior accessory GSV of the calf

(posterior arch vein) with the posterior tibial

vein. There are three of them: lower, middle,

and upper, located just behind the medial

malleolus and at 7–9 cm and 10–12 cm from

the lower edge of the medial malleolus

respectively. They are at 2–4 cm behind the

medial edge of tibia. In perforator surgery,

these are the vessels which are mainly tar-

geted (Fig.

2.2 ).

(b) Para-tibial perforators connect the main GSV

trunk to the posterior tibial veins.

2 Lower Limb Venous Anatomy

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Below knee perforating veins : These are the

anterior, lateral, and gastrocnemius vessels. The

gastrocnemius vessels are arranged into medial

and lateral groups. Intergemellar and Achillean

perforating veins are the other groups of below

knee perforators.

The perforators located around the knee :

These are infra- and suprapatellar and popliteal

fossa perforating veins.

Perforators of the femoral canal : In the distal

thigh, perforators of the femoral canal connect

the femoral vein to the GSV.

Inguinal perforators : These drain into the

femoral vein in the proximal thigh.

Valves of the Lower Limb Veins

One of the most important anatomical features of

veins from a clinical perspective is the presence

of valves. Each of these delicate, but extremely

strong, bicuspid structures lies at the base of a

segment of the vein that is expanded into a venous

sinus. This arrangement permits the valves to

open widely without coming into contact with

the wall, thus permitting rapid closure when ﬂ ow

begins to reverse.

There are approximately 9–11 valves in the

anterior tibial, 9–19 in the posterior tibial, 7 in

the peroneal, 1 in the popliteal, and 3 in the femo-

ral vein. In two-thirds of the femoral veins, a

valve is present at the upper end within 1 cm of

the inguinal ligament. About one-quarter of the

external iliac veins have a valve. The common

iliac vein usually has no valves. Superﬁ cial veins

have fewer valves – approximately seven to nine

in the greater and lesser saphenous veins.

Electron microscopy of resin-ﬁ lled veins in

cadavers conﬁ rmed the presence of valves up to the

sixth generation tributaries [

15 ]. Incompetence of

these valves is reported to be one of the important

causes for the development of skin changes includ-

ing ulcers in patients with chronic venous disorders.

Venous Sinuses of the Calf Muscle

These are large thin-walled blood-ﬁ lled spaces

located mostly in the soleus (1–18 sinuses) and to

a less extent in the gastrocnemius muscle. Venous

sinuses of the soleus muscle drain into the poste-

rior tibial vein through multiple large, short, and

tortuous soleus veins. Some of these veins may

join a perforating vein before entering the deep

veins. Gastrocnemius veins drain the two heads

of the muscle and empty into the popliteal vein

distal to the SP junction. These sinuses are ﬁ lled

from the superﬁ cial veins and the reticular venous

plexuses. They can hold a large volume of blood

and can function as chambers of the peripheral

heart [

2 ].

Veins of the Foot

The anatomy of the foot veins has been reported

extensively by Uhl and Gillot by their dissection

study on 400 cadaveric feet after injecting green

GSV

Posterior accessory GSV of leg

Upper

Middle

Lower

Medial

Lateral

Ankle

Perforators

Posterior tibial group of

Medialcalf perforators

Fig 2.2 Posterior tibial group of medial calf perforators

Anatomy of Lower Limb Venous System

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neoprene latex [ 16 ]. The summary of their ﬁ nd-

ings is as follows:

Components of the foot veins include the

superﬁ cial venous network, the deep veins, and

the perforating veins.

Superﬁ cial venous network consists of plantar

network draining into marginal veins, medial and

lateral marginal veins connecting the GSV and

SSV respectively, and the interdigital veins.

Deep veins are located in two layers: deep

bony veins in contact with tarsal bones and large

collecting veins – musculotendinous veins. They

converge as medial and lateral plantar pedicles.

Perforators . There are several perforating

veins in the foot. The named ones are as follows:

• Perforator of the ﬁ rst metatarsal interspace

• Medial marginal perforator vein

• Plantar perforators (malleolar, navicular, and

cuneiform)

• Dorsal medial perforator

• Lateral marginal perforator veins

The foot muscle pump has been the subject of

extensive studies in recent times. The volume of

blood pumped by foot muscle pump is calculated

as 25 ml. Two points regarding the foot muscle

pump deserve attention [

16 ]:

1. The direction of more than 50 % of valves in

the veins of the foot is such that the blood ﬂ ow

is from deep to superﬁ cial veins when the foot

muscle pump contracts.

2. Impairment of the foot muscle pump by static

foot disorder is an important cause of chronic

venous disorder.

Ultrasound Anatomy of Lower

Limb Veins

Duplex ultrasound imaging of the lower limbs is

currently the gold standard for the diagnosis of

CVD. Some of the well-described features of US

imaging are mentioned below [ 3 , 17 – 19 ].

Ultrasonographic eye sign . US visualization

of the GSV in the upper thigh gives the classical

Egyptian eye appearance with the vein sitting

between the two fascias. In a transverse imaging,

the saphenous fascia is the upper eyelid, muscu-

lar fascia the lower eyelid, and the saphenous

vein the iris [ 3 , 4 ] (Fig. 2.3 ).

The tibiogastrocnemius angle sign has been

described to identify the GSV in the leg using a

duplex scan, during a difﬁ cult cannulation for

endovenous ablation. The angle or triangle is

made by the tibia laterally, the gastrocnemius

muscle medially, and the fascia superﬁ cially.

Here, the GSV ascends in front of the tibial mal-

leolus and along the medial side of the leg.

The lateral subdermal venous system is a system

of small caliber veins extending above and below

the knee on the lateral aspect. The direction of ﬂ ow

is downward in this system. This represents the

remnant of the embryonic lateral marginal vein [

3 ].

Summary

Sound knowledge of anatomical arrangement of

veins of lower limbs is essential for a clinician

dedicated to the care of patients with CVD. There

is a well-deﬁ ned pattern of arrangement of the

veins, although variations are very common.

The veins are arranged in two compartments –

the superﬁ cial and deep. A well-deﬁ ned space in

the superﬁ cial compartment known as the saphe-

nous compartment houses the GSV and the

saphenous nerve.

The veins are arranged in three patterns – super-

ﬁ cial veins, deep veins, and perforating veins. The

GSV and SSV are the superﬁ cial veins. All other

terminology for these veins has been abandoned.

With the advent of US in the diagnosis of

venous diseases, certain patterns of anatomy are

well recognized. Some of these ﬁ ndings are high-

lighted in this chapter.

2 Lower Limb Venous Anatomy

https://t.me/med1917

References

1. Dodd H, Cockett FB. The pathology and surgery of

the veins of the lower limb. 2nd ed. Edinburgh:

Churchill Livingstone; 1976. p. 160.

2. Gloviczki P, Mozes G. Development and anatomy of

the venous system. In: Gloviczki P, editor. Handbook of

venous disorders; guidelines of the American Venous

Forum. 3rd ed. London: Hodder Arnold; 2009. p. 12–23.

3. Caggiati A, Bergan JJ, Gloviczki P, Jantet G, Wendell –

Smith CP, Partsch H. Nomenclature of the veins of the

lower limbs: an international interdisciplinary consen-

sus statement. J Vasc Surg. 2002;36:416–22.

4 . O ğuzkurt L. Ultrasonographic anatomy of the lower

extremity superﬁ cial veins. Diagn Interv Radiol. 2012;

18:423–30.

5. Standring S, editor. Gray’s anatomy; the anatomical

basis of clinical practice . 39th ed. Elsevier,

Philadelphia; 2005. p. 1452.

6. Gloviczki P, Comerota AJ, Dalsing MC, Eklof BG,

Gillespie DL, Gloviczki ML, Lohr JM, Mc Lafferty RB,

Meissner MH, Murad MH, Padberg FT, Pappas PJ,

Passman MA, Raffeto JD, Vasquez MA, Wakeﬁ eld TW.

The care of patient with varicose veins and associated

chronic venous diseases: clinical practice guidelines of

the Society for Vascular Surgery and the American

Venous Forum. J Vasc Surg. 2011;53(5 suppl):2s–48.

Superficial

fascia

membranous

GSV

Deep fascia

USG Egyptain eye

Fig 2.3 US appearance of the GSV in the superﬁ cial compartment

References

https://t.me/med1917

7. Donnelly M, Tierney S, Feeley TM. Anatomical vari-

ation at the saphenofemoral junction. Br J Surg. 2005;

92:322–5.

8. Dodd H, Cockett FB. The pathology and surgery of

the veins of the lower limb. 2nd ed. Edinburgh:

Churchill Livingstone; 1976.

9. Standring S, editor. Gray’s anatomy; the anatomical

basis of clinical practice. 39th ed. Elsevier,

Philadelphia; 2005. p. 1507.

10. Kerver ALA, van der Ham AC, Theeuwes HP, Eilers

PHC, Poublon AR, Kerver AJH, Klienrensink GJ. The

surgical anatomy of the short saphenous vein and

adjacent nerves in relation to endovenous thermal

ablation. J Vasc Surg. 2012;56(1):181–8.

11. Delis KT, Knaggs AL, Khodabaksh P. Prevalence,

anatomic pattern, valvular competence and clinical

signiﬁ cance of the Giacomini vein. J Vasc Surg. 2004;

40:1174–83.

12. Georgiev M, Myers KA, Belcaro G. Giacomini’s

observations on the superﬁ cial veins of the limb and

principally the external saphenous. Int Angiol. 2001;

20(3):251–64.

13. May R, Partsch H, Staubes J. Perforating veins.

Mu¨nchen: Urban and Schwarzenberg; 1980.

14. Kuster G, Lofgren EP, Hollinshead WH. Anatomy of

the veins of the foot. Surg Gynecol Obstet. 1968;

127:817–26.

15. Vincent JR, Jones GT, Hill GB, van Rij AM. Failure

of microvenous valves in small superﬁ cial veins is a

key to the skin changes of venous insufﬁ ciency. J Vasc

Surg. 2011;54(6 Suppl):62S–9S.e1-3.

16. Uhl JF, Gillot C. Anatomy of the foot venous pump:

physiology and inﬂ uence on chronic venous disease.

Phlebology. 2012;27(5):219–30.

17. Chen SSH, Prasad SK. Long saphenous vein and its

anatomical variations. Aust J Ultrasound Med. 2009;

12(1):28–31.

18. Cavezzi A, Labropoulos N, Partsch H, et al. Duplex

ultrasound investigation of the veins in chronic venous

disease of the lower limbs-UIP consensus document.

Part II. Anatomy. Eur J Vasc Endovasc Surg. 2006;31:

288–99.

19. Ricci S, Georgiev M. Ultrasound anatomy of the super-

ﬁ cial veins of the lower limb. J Vasc Technol. 2002;

26:183–99.

2 Lower Limb Venous Anatomy

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S. Vaidyanathan et al., Chronic Venous Disorders of the Lower Limbs: A Surgical Approach,

DOI 10.1007/978-81-322-1991-0_3, © Springer India 2015

Introduction

The venous system of the lower limbs is an

organized and functional unit. Returning blood to

the heart is its primary function. Several factors are

involved in the control of this system. These include

gravity, the reservoir capacity, venous tone, sympa-

thetic control of smooth muscles, and many other

mechanisms. Most of our misunderstanding of

venous diseases stems from the inability to appre-

ciate the delicate anatomy and physiology. Details

of anatomy were considered in Chap. 2 .

This chapter focuses on the physiology of the

lower limb venous system. In this section, we

plan to discuss the following:

• Physiology of normal venous drainage

• Altered hemodynamics in venous disorders

A simple and effective way to comprehend

venous physiology would be to consider the ﬂ ow

and pressure patterns in health and disease. In

the clinical setting, this information is obtained

by the ambulatory venous pressure (AVP)

studies.

Normal Venous Drainage

of Lower Limbs

The peripheral venous system functions as a res-

ervoir to store blood and as a conduit to return

blood to the heart. In a person in the erect pos-

ture, blood entering the lower-extremity venous

system must travel against gravity and against

Venous Physiology

and Hemodynamics

of Lower Limbs

Riju Ramachandran Menon

Contents

Introduction ............................................................ 17

Normal Venous Drainage of Lower Limbs .......... 17

The Veins of Lower Limb ......................................... 18

Venous Valves ........................................................... 18

Muscle Pumps ........................................................... 18

Correlation with Ambulatory Venous

Pressure Studies ..................................................... 20

Abnormal Hemodynamics in Chronic

Venous Disorders .................................................... 20

Reﬂ ux in Superﬁ cial Veins ........................................ 21

Reﬂ ux/Obstruction of the Deep Veins ...................... 21

Incompetence of Perforators ..................................... 22

Summary ................................................................. 23

References ............................................................... 23

R.R. Menon

General Surgery , Amrita Institute of Medical

Sciences, Amrita Lane , Kochi , Kerala 682041, India

e-mail:

rijurmenon@gmail.com

https://t.me/med1917

ﬂ uctuating thoracoabdominal pressures to return

to the central circulation. Proper functioning of

the system depends on the coordinated function-

ing of several parts.

There are three components of the venous sys-

tem. These are the veins of the lower limb, the

valves in the veins, and the muscle pumps.

The Veins of Lower Limb

The veins of the lower extremity are arranged

into the superﬁ cial, deep, and perforating

systems [ 1 ]. Blood ﬂ ow in these veins is always

unidirectional and cephalad. Gravity and hydro-

static pressure oppose venous return in the

upright position. A system of valves, an efﬁ cient

peripheral pump mechanism, and a negative

intrathoracic pressure overcome the effects of

gravity [ 2 , 3 ].

The superﬁ cial venous system comprising the

GSV and SSV and the interconnecting network

of veins function as conduits to return blood to

the deep venous system [ 2 ]. The predominant

ﬂ ow from the saphenous system is through the

perforator into the deep veins. This arrangement

is especially dominant during activity. Blood sel-

dom travels up along the entire length of the

superﬁ cial veins except when the deep veins are

blocked. Eighty percent of the blood from the

lower limb is conveyed to the heart through the

deep venous system.

The deep venous system is located below

the muscular fascia and serves as collecting

veins and the outﬂ ow from the extremity.

Venous sinuses of the gastrocnemius and

soleus muscles are blood-ﬁ lled spaces with a

capacitance function and serve as chambers of

the peripheral heart. The venous sinuses drain

to the deep veins. The deep veins are sur-

rounded by powerful muscle and the deep fas-

cia of the leg.

The perforating veins connect the deep and the

superﬁ cial system. Their primary function is as

drainage conduits from superﬁ cial to the deep

system.

Venous Valves

• The superﬁ cial, deep, and most perforating

veins contain bicuspid valves formed from

folds of endothelium, supported by a thin

layer of connective tissue. Valves are most

numerous in the distal leg and decrease in

number in the upper part of the limb [ 4 ].

Valves subserve two functions:

• They promote unidirectional cephalad ﬂ ow

toward the heart.

• They break the hydrostatic column of blood

into segments.

Normally, at rest, the valves remain open. The

valves close during muscular activity. This is a

passive event and is initiated by a higher pressure

in the supravalvular segment produced by pos-

ture and muscle activity. There is a transient

phase of retrograde ﬂ ow lasting for less than

0.5 s. This retrograde ﬂ ow must be of sufﬁ cient

velocity to coapt the cusps completely [ 5 ]

(Fig. 3.1 ).

In the upright posture, a reﬂ ux lasting less

than 0.5 s is physiological; if the duration exceeds

0.5 s, it is deﬁ ned as pathological reﬂ ux. The

importance of incompetence of a single valve or

several valves in genesis of clinical effects is not

deﬁ nitely known [ 2 ].

Muscle Pumps

The calf muscle pump is the most powerful force

that facilitates venous return from the lower

limbs. The thigh and foot muscle pumps also

function to some extent toward this purpose.

Contraction of the calf muscle pump increases

the pressure within the fascial compartments and

forces blood up along the deep venous system

( systole of the muscle pump ). The competent

valves prevent reﬂ ux distally within the deep

venous system or through the perforators into the

superﬁ cial veins (Fig. 3.2 ).

When the calf muscles relax, the pressure in

the fascial compartment drops. During this phase,

blood from the superﬁ cial veins and the sinuses

3 Venous Physiology and Hemodynamics of Lower Limbs

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ﬁ lls the deep system through the perforating

veins ( diastole of the muscle pump ). The deep

fascia of the leg supports the muscle pump con-

siderably. The net effect of a series of contrac-

tions of the calf muscle pump would be to

promote a streamlined, unidirectional, and ceph-

alad ﬂ ow toward the heart. This effectively

reduces the pressure and volume in the superﬁ -

cial venous system during ambulation [

3 , 6 ].

The thigh muscle pump is not as powerful as

the calf muscle pump in spite of the fact that

these muscles are bulkier. Two reasons are attrib-

uted for its less powerful action – rapid reﬁ ll and

less compressible intermuscular location of the

deep veins in the thigh [ 2 ]. The ejection fraction

of the calf muscle pump is around 65 %, in com-

parison with only 15 % for the thigh pump [ 6 ].

The foot and lower leg biomechanics also play

a major role in venous return. When the sole of

Fig. 3.1 Mechanism of valve closure

SFJ

80 % flow 20 % flow

GSV

Formoral vein

Fig. 3.2 Normal venous drainage of lower limb

Normal Venous Drainage of Lower Limbs

https://t.me/med1917

the foot makes contact with the ground, the

lateral plantar veins are emptied and blood is

forced into the posterior tibial veins. This marks

the ﬁ rst but essential step of venous return from

the lower limbs. The calf muscle pump then

sequentially takes over from the foot muscle

pump [ 7 ]. When the foot muscle pump contracts,

50 % of the perforators of the foot permit ﬂ ow

from the deep to the superﬁ cial veins [ 2 ]. The

role of the foot muscle pump could be crucial in

the genesis of chronic venous disorders. It has

been identiﬁ ed that static foot disorders may be

associated with impaired venous return from the

lower limbs [ 7 ].

In an average individual walking 100 steps a min-

ute, the combined stroke volume of the calf muscle

pumps of both sides is estimated as 6.0 l/min

2 .

Correlation with Ambulatory

Venous Pressure Studies

In the clinical setting, the function of the calf

muscle pump is best demonstrated by recording

the ambulatory venous pressure (AVP) in the foot

veins. AVP studies are primarily aimed at record-

ing the drop in venous pressure in the superﬁ cial

veins of the foot following a series of calf muscle

contractions such as standing on toes [ 8 ].

A foot vein is cannulated and connected to a

pressure transducer and a three-channel recorder

or a manometer system through a three-way

stopcock and a saline reservoir. The pressure in

the foot vein with the patient standing upright

and at rest is ﬁ rst recorded – resting pressure

(RP). This will be roughly equivalent to the

weight of the column of blood from the right

heart to the point of measurement and varies

according to the height of the individual. On an

average, it is around 100 mm of Hg. The subject

is asked to perform a series of standing on toe

movements with the cannula in situ. This will

produce a powerful contraction of the calf mus-

cle. The pressure after a series of 10–15 contrac-

tions drops down by 50–60 % and thereafter

remains steady irrespective of the extent of

activity . The lowest pressure recorded after the

series of muscle contractions is designated as

the postexercise pressure (PEP). On cessation of

the exercise, when the subject is at rest, the pres-

sure slowly returns to the original resting value.

The time taken for the PEP to return to the RP is

designated as the recovery time (RT). In normal

subjects, this is about 20–30 s. This AVP pattern

is known as the normal venous pattern (Fig. 3.3 ).

In patients with venous disorders, the drop in

PEP is very negligible. Also, the recovery time is

much faster (0–5 s). Thus the AVP pattern, nor-

mal and abnormal, can give an insight into the

functioning of the calf muscle pump in health and

disease.

Abnormal Hemodynamics

in Chronic Venous Disorders

As we have seen in the previous section, the

activity of the calf muscle pump reduces the pres-

sure and volume of blood in the superﬁ cial

venous system. This remarkable ability of the

muscle pump is diminished in patients with

venous disorders of the lower limbs, resulting in

a persistently elevated PEP. In clinical parlance,

this is referred to as ambulatory venous hyperten-

sion . Side by side, the RT is short from rapid

reﬂ ux reﬁ lling. The pathological situations

100

Normal venous pattern

Pressure in mmHg

without PSO

Time in sec

Fig. 3.3 AVP normal venous pattern. Note the prominent

drop in PEP. ( A ) Resting pressure at start of exercise. ( B )

Maximum pressure fall with exercise. ( BC ) Recovery

time

3 Venous Physiology and Hemodynamics of Lower Limbs

https://t.me/med1917

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