choose of the best valvular competence test
Post on 05-Jul-2015
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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
Force of the gradient
Increasing Decreasing
B
A
Force of the gradient
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
Squeezing ParanàTime A 751 1078
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
Squeezing ParanàTime A 468 764
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
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