choose of the best valvular competence test

Stefano Ermini MDFirenze

Considerations about the valve competence tests

To be US detected, there must be an increase in speedof the venous flow

To increase the venous flow speed we must create a pressure gradient.

Pressure Gradient = Force directed from high to lowpressure. The change in pressure measured across a given distance is called a "pressure gradient".

Considerations about applying a pressure gradient to the venous system

A flow originates in a competent system only ifthe pressure gradient has the same valve direction

If there is no valve competence, the flow has the same direction as the pressure gradient.

When the patient is standing , a force is alsorepresented by the hydrostatic pressure

A pressure Gradient may be Propulsive and/or Aspirative

B

A

B

A

Propulsive Aspirative

Force of the gradient

Muscle PumpSystole

(contraction)

Muscle Pump Dyastole(relaxation)or Manual Compression/release


Increasing Decreasing

B

A


Valsalva Manouvre

Increasing

Pre

ssu

re

Flo

w

Pre

ssu

re

Flo

w

-

++

-X

X

Relaxed breathing in a standing position

Valsalva Manouvre : 1)Forced Inspiration2)Blocked expiration

1) Applyng force like that of a bowel movement2) Blowing into a closed straw ( Franceschi)

Resting Valsalva( Clamp effect)

The residual Venous Pressure creates an increase in pressure

and venous diameter

Valsalva Manouvre in a Normal Subject

Valsalva Manouvre in SFJ incompetence

Situation A( Without Femoro-Iliac valve)

Situation B( With Femoro-Iliac valve)

Manual Calf Compression ( Squeezing) - Systolic Phase

LSV Incompetence

CompressionArea of Blood Mobilization

Manual Calf Compression ( Squeezing) - Dyastolic Phase

LSV Incompetence

RelaxationEmptied Zone

Active Muscle pump activity - Systolic PhaseLSV Incompetence

Area of Blood Mobilization

Active Muscle pump activity - Dyastolic Phase

LSV Incompetence

Emptied Zone

Point A

Point B

Gradient Line

Squeezing Test : The Gradient only involvessuperficial veins

Gradient Line

Point A

Point B

Dynamic Tests : The Gradient involves superficial veins, perforators and deep veins

Gradient LineTime duration of centrifugal flow

= Time of gradient

exaustion

Dynamic tests are still not accepted by the international community

The most well-known dynamic test is the Paranà Manouvre, described by Claude Franceschi in 1998.

To check its validity, I have compared this manouvre with the squeezing test in the following patient series/situations :A. Popliteal vein in healthy subject - 20 patientsB. Incompetent SFJ , with incompetent terminal v., in varicose veins

- 13 patientsC. Incompetent saphenous axis 15 cm below the groin in cases with

an incompetent terminal valve - 13 patientsD. Re-entry perforators in varicose veins subjects - 11 patients

Both the Paranà Manouvre and the Squeezing Test are not mechanical tests but their results depend on a series of variables:For the Squeezing Test:Manual compression strengthMuscle contraction / relaxation level while the patient is standingLeg volume For the Paranà ManouvrePushing forceMuscle contraction / relaxation level while the patient is standingA support point for the patient

PullPush

A B

The force applied, produces a flow movement , that in an arcof time reaches the maximum speed that decreases later.The increase of speed in an arc of time is called“ acceleration” .

Paranà and Squeezing test in a healthy Popliteal Vein

Area= (Speed xTime A /2) + (Speed x Time B/2)Acceleration = Max Speed/Time A

Max Speed

Time A Time B

Time A Time B

Max Speed

Squeezing and Paranà in an incompetent Saphenous Trunk

Speed A

Time B

Time A

Speed B

Area A = ( Speed A x Time A )/2Area B =( Speed B x Time B)/2

Time A

Time BMax Speed A

Max Speed B

To determine if the average variation is similar in the squeezing test and the Paranà manouvre group we have calculated the acceleration and its “Standard Deviation”.

Standard Deviation shows how much variation from the average exists.

A. The Paranà manouvre and Squeezing test have some variables that change the final result

B. The energy applied to the venous system gives origin to a flow acceleration thatis detected by the US.

We have said that:

The higher the standard deviation, the lower the test accuracy

Examinations done

Vein examined Number of cases Total measurementsdone

Popliteal vein in healty subjects 20 patients 120 measurements

Incompetent SFJ 13 patients 156 measurements

Incompetent LSV axis 13 patients 156 measurements

Re-entry perforators 11 patients 143 measurements

TOTAL 57 patients 575 measurements

One of the Excel spread sheet

Mean ( μ )

Coefficient of variation C V

Standard Deviation ( 𝞂 )

Squeezing Acceleration Paranà Acceleration

Healthy Popliteal Vein

AverageSqueezing

AverageParanà

𝞂 Squeezing 𝞂 Paranà

Healthy Poplitea 0,19 0,13 0,06 0,07

Incompetent SFJ 0,06 0,11 0,02 0,14

Incompetent GSV 0,06 0,04 0,04 0,02

Re-Entry Perforator 0,07 0,03 0,04 0,01

In the Paranà group standard deviation is similar or lowerthan in the squeezing group. This means that the Paranà

manouvre is more accurate than the squeezing test.

Standard deviation (𝞂 )

Popliteal Vein in Healthy subjects ( 20 cases)

Squeezing Paranà

Tempo A (ms) 379 593

Tempo B 349 546

Max Speed cm/sec 68 72

Area 25033 41657

Area :

In 3 cases the squeezing test moves 10% more than the Paranà In 17 cases the squeezing test moves 40% less than the Paranà

Area measurement

Incompetent Saphenous Axis

Squeezing ParanàTime A 501 571

Speed A 45 26

Area A 12683 9695

Time B 4332 7881

Speed B 35 40

Area B 66533 144392

Syst

olic

Even

tsD

iast

olic

Even

ts

The centrifugal relaxation ( diastolic) flow is more than double in the Paranà compared to the squeezing test

Incompetent SFJ


Speed A 45 34

Area A 16100 18502

Time B 2269 5808

Speed B 43 71

Area B 48597 185478

Syst

olic

Even

tsD

iast

olic

Even

ts

The centrifugal relaxation ( diastolic) flow is more than triple in the Paranà compared to the squeezing test

Re-entry perforator


Speed A 28,35 26,08

Area A 6605 10722

Time B 1488 4861

Speed B 22,76 45,96

Area B 19057 92476

Syst

olic

Even

tsD

iast

olic

Even

ts

The centrifugal relaxation ( diastolic) flow is more than four times greater in the Paranà.

Conclusions

Standard deviation acceleration shows that the Parana manouvre is more accurate than the squeezing test.

In healthy subjects the Paranà manouvre moves40% more blood than in the squeezing test.

In incompetent systems, the diastolic phase of the Paranà manouvre’s flow lasts 3 times longerthan the squeezing test.

The Parana manouvre is more accurate and more effective than the squeezing test.

Thanks for your

attentionStefano Ermini MD

PullPush

A B

Paranà Test versus Toe Standing Test in the Popliteal Vein in Healthy subjects ( 20 cases)

Toe standing Paranà

Tempo A (ms) 343 561

Tempo B 332 549

Max Speed cm/sec 109 70

Area 36155 39172

Accelerazione 0,34 0,13

Valsalva Manouvre in deep vein incompetence

Situation A( Without VV Shunt)

Situation B( With VV Shunt)

Corso di Flebologia Emodinamica e Linfologia

Con sessioni teorico-pratiche

Università di Camerinodirettore e vicedirettore : Amenta-Bernardini

docenti: Bernardini-Cappelli-Ermini- Castagnoli-Moretti

PushSupport pointfor the patient

choose of the best valvular competence test

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