DOES ANEURYSM SAC STABILIZATION DURING EVARDOES ANEURYSM SAC STABILIZATION DURING EVAR

REDUCE THE INCIDENCE OF ENDOLEAKS?REDUCE THE INCIDENCE OF ENDOLEAKS?

SEVEN YEARS EXPERIENCESEVEN YEARS EXPERIENCE

DEPARTMENT OF CARDIOVASCULAR DISEASESDIVISION OF VASCULAR AND ENDOVASCULAR SURGERY

Chief: Salvatore Ronsivalle, MD

S.Paulo April 20-24

CICE2010

CICE2010

BACKGROUNDBACKGROUND

EVAREVAR (endovascular aneurysm repair) is an increasingly used method of (endovascular aneurysm repair) is an increasingly used method of

repairing aortic abdominal aneurysmrepairing aortic abdominal aneurysm

TYPE II ENDOLEAK is TYPE II ENDOLEAK is

the most common form of complication (20-30%), due to partial and the most common form of complication (20-30%), due to partial and

incomplete spontaneously early or late “ thrombization” of the aneurysm incomplete spontaneously early or late “ thrombization” of the aneurysm

sac after EVAR; it is joined by its retrograde perfusion from aortic collateral sac after EVAR; it is joined by its retrograde perfusion from aortic collateral

branches branches

Its management is still debatedIts management is still debated

TREATMENTTREATMENT TYPE II ENDOLEAKTYPE II ENDOLEAK

Preoperative embolization (IMA, LA)Preoperative embolization (IMA, LA)

Embolization therapy (transarterial, translumbar)Embolization therapy (transarterial, translumbar)

Laparoscopic retroperitoneal lumbar branches ligationLaparoscopic retroperitoneal lumbar branches ligation

Open traditional surgeryOpen traditional surgery

PRESENT AND FUTUREPRESENT AND FUTURE

Prevention is the best strategy to use in managing this complicationPrevention is the best strategy to use in managing this complication

The stimulation and acceleration of a complete aneurysm The stimulation and acceleration of a complete aneurysm

sac “ thrombization “ with the introduction of biocompatible sac “ thrombization “ with the introduction of biocompatible materials materials

in the aneurysm sac performed during EVAR seems to be promisingin the aneurysm sac performed during EVAR seems to be promising

BIOMATERIALSBIOMATERIALS

FIBRIN SEALANT FIBRIN SEALANT is a fully absorbable biologic adhesive matrix is a fully absorbable biologic adhesive matrix

made of two main components 1) made of two main components 1) fibrinogen solutionfibrinogen solution containing containing plasma coagulation proteins and 2) plasma coagulation proteins and 2) thrombin solution thrombin solution containing containing

aprotinin (antifibrino-litic agent)aprotinin (antifibrino-litic agent)

INCONEL INCONEL (nickel and cobalt alloy) (nickel and cobalt alloy) COILS COILS are radiopaque, allow are radiopaque, allow

MRI scanning, CT and CDU imagingMRI scanning, CT and CDU imaging

CT SCANCT SCAN

Control CT scan with evident inconel coils

ANGIOGRAPHY DURING EVARANGIOGRAPHY DURING EVAR

Final angiography performed to verify sac thrombization and root occlusion of lumbar and inferioir mesenteric arteries

September 1999 September 1999 December 2009December 2009

545 patients 545 patients underwent EVARunderwent EVAR

September 1999 September 1999 May 2003May 2003

228 pts: EVAR standard procedure228 pts: EVAR standard procedure

June 2003June 2003December 2006December 2006

131 pts: EVAR plus fibrin glue 131 pts: EVAR plus fibrin glue

January 2007January 2007December 2009December 2009186 pts: EVAR 186 pts: EVAR

plus inconel coils and fibrin glue plus inconel coils and fibrin glue

POPULATIONPOPULATION

STUDY COHORT BASELINE DEMOGRAPHIC CHARATERISTICSSTUDY COHORT BASELINE DEMOGRAPHIC CHARATERISTICS

GROUP I (EVAR alone)

GROUP II (EVAR plus thrombization)

(N 228) (N 254)

MALE 213 (93.4%) 232 (91.3%) §

FEMALE 15 (6.6%) 22 (8.7 %) §

AGE (YEARS) + SD 71.8 ± 8.5 72.5 ± 7.5 **

SMOKE 53 (23.2%) 32 (12.6%) *

FAMILIARITY FOR AAA 2 (0.8%) 2 (0.7%) §

CHRONIC RENAL FAILURE 54 (23.7%) 46 (18.1%) §

CAROTID ARTERY DISEASE 91 (39.9%) 150 (59.1%) *

PERIFERIC ARTERY DISEASE 80 (35.1%) 36 (14.2%) *

BMI > 30 47 (20.6%) 52(20.5%) §

HYPERTENSION 193 (84.6%) 240 (94.5%) *

CARDIAC DISEASE 126 (55.3%) 161 (63.4%) §

DIABETES MELLITUS 41 (18.0%) 50 (19.7%) §

HYPERLIPIDEMIA 152 (66.7%) 215 (84.6%) *

§ Pearson χ2 : p>0.05

* Pearson χ2 : p<0.05

** t-test : p>0.005 Armando Olivieri MD, Department of Prevention - Epidemiology Unit

STUDY COHORT ANATOMIC PARAMETERSSTUDY COHORT ANATOMIC PARAMETERS

group

AAA NECKcommon right iliac

common left iliac

diam. length diam length

EVAR alone 58.0 ± 13.0 70.8 ± 24.9 23.1 ± 2.7 27.3 ± 10.7 15.5 ± 6.7 17.1 ± 10.1

EVAR plus thrombization 58.4 ± 14.1 71.6 ± 21.3 23.4 ± 2.8 28.8 ± 13.1 17.0 ± 10.9 15.6 ± 5.7

t-test p=0.7187 p=0.7167 p=0.1989 p=0.1729 p=0.0714 p=0.0588

Armando Olivieri MD, Department of Prevention - Epidemiology Unit

STUDY COHORT ANATOMIC PARAMETERSSTUDY COHORT ANATOMIC PARAMETERS

groupmain stent

graft

AAA NECK

common right iliac

common left iliacdiam. length diam length

EVAR alonesuprarenal

graft60.5 ± 12.6

71.1 ± 2614

23.5 ± 2.8 27.0 ± 9.7 15.4 ± 6.4

17.5 ± 10.8

EVAR plus thrombization

suprarenal graft

58.9 ± 13.4

71.8 ± 21.6

23.5 ± 2.9

27.2 ± 12.6

17.3 ± 11.3 15.7 ± 5.6

EVAR aloneinfrarenal

graft52.9 ± 12.5

70.1 ± 22.5

22.3 ± 2.6

28.1 ± 12.6

15.8 ± 7.4

16.2 ± 8.5

EVAR plus thrombization

infrarenal graft

57.5 ± 15.6

71.0 ± 20.6

23.2 ± 2.7

32.5 ± 13.5

16.1 ± 6.9

15.3 ± 6.0

Armando Olivieri MD, Department of Prevention - Epidemiology Unit

INCIDENCE RATEINCIDENCE RATE

cohort person-time (months)

failures (num)

rates (x 1000 person-months)

EVAR alone 15770 34 2,16

EVAR plus sac thrombization 8539 7 0,82

total 24309 41 1,69

Incidence rate was 2.16 rates * 1000 person-month for EVAR alone group and 0.82 rates * 1000 person-months for EVAR plus thrombization

Armando Olivieri MD, Department of Prevention - Epidemiology Unit

KAPLAN MAYER SURVIVING CURVEKAPLAN MAYER SURVIVING CURVE

Armando Olivieri MD, Department of Prevention - Epidemiology Unit

0.0

00.2

50.5

00.7

51.0

0

cum

ula

tive p

roba

bili

ty

253 230 152 95 74 43 12 0 0 0 0EVAR plus thrombization227 188 174 167 162 154 148 119 61 44 20EVAR alone

Number at risk

0 12 24 36 48 60 72 84 96 108 120follow up in months

EVAR alone EVAR plus sac thrombization

log-rank test p=0.0000

Kaplan–Meier Curves for the Primary End Point (endoleak type II)

RISK (HAZARD RATIO) FOR TYPE II ELRISK (HAZARD RATIO) FOR TYPE II EL

ADJUSTED FOR SURGICAL TECHNIQUE,GENDER AND OBESITYADJUSTED FOR SURGICAL TECHNIQUE,GENDER AND OBESITY

Armando Olivieri MD, Department of Prevention - Epidemiology Unit

  Hazard

Ratio p I.C. 95%

         

surgical technique        

EVAR alone 1,00      

EVAR plus sac thrombization 0,13 0,000 0,05 0,36

         

gender        

male 1,00      

female 0,32 0,007 0,14 0,74

         

obesity        

normal/overweight 1,00      

BMI>30 0,10 0,023 0,01 0,73

SEPT 1999-MAY 2003

228 ptsJUNE 2003-DEC 2008

254 pts

TYPE II ENDOLEAK TOTAL

34 7

STABLE IN FOLLOW UP 6 (18 %) 3 (43 %)

SPONTANEUSLY RESOLVED 11 (32 %) 3 (43 %)

SPONTANEUSLY RETIRED5 (15 %) 1 (14 %)

TREATED WITH SURGERY(CONVERTION)

3 (9%) -

TREATED WITH SURGERY(PARTIAL CONVERTION) 1 (3%) -

DIED 8 (23%)-

TYPE II ENDOLEAKTYPE II ENDOLEAK September 1999 – December 2008

DISCUSSION DISCUSSION

Biomaterials used for intrasac thrombization are inserted between main stentgraft Biomaterials used for intrasac thrombization are inserted between main stentgraft

and aneurysmal wall as a means or method to form an enclosureand aneurysmal wall as a means or method to form an enclosure

Due to a fibrin sealant injection, the coils form a structure that accelerates and Due to a fibrin sealant injection, the coils form a structure that accelerates and

consolidates the clot formation process forming a “concrete” compound, resulting consolidates the clot formation process forming a “concrete” compound, resulting

in manifesting a durable, long lasting, sturdy stabilization of the whole complex in manifesting a durable, long lasting, sturdy stabilization of the whole complex

fixed en bloc fixed en bloc

Fibrin glue injection did not cause microembolization or any allergic or Fibrin glue injection did not cause microembolization or any allergic or

anaphilactic reactionsanaphilactic reactions

TREATMENT VERSUS PREVENTIONTREATMENT VERSUS PREVENTION

Previous studies have demonstrated a high rate of success (92% Baum et al J Previous studies have demonstrated a high rate of success (92% Baum et al J

Vasc Interv Radiol 2001; 12:111-6 and 71 % Timaran et al J Vasc Surg 2004; Vasc Interv Radiol 2001; 12:111-6 and 71 % Timaran et al J Vasc Surg 2004;

39:1157-62) using translumbar embolization in the treatment of persistent EL 39:1157-62) using translumbar embolization in the treatment of persistent EL

type II with sac enlargementtype II with sac enlargement

After the introduction of our preventive technique we had a significantly lower After the introduction of our preventive technique we had a significantly lower

incidence of EL II which accords with the high percentage of success rate in incidence of EL II which accords with the high percentage of success rate in

translumbar embolizationtranslumbar embolization

We prevent complications in almost all treated patients as translumbar We prevent complications in almost all treated patients as translumbar

embolization resolves EL II in a high percentage of treated casesembolization resolves EL II in a high percentage of treated cases

WHY PREVENTION ?WHY PREVENTION ?

EVAR plus a preventive aneurysm sac “ thrombization “ costs about 630 EVAR plus a preventive aneurysm sac “ thrombization “ costs about 630

dollars more than EVAR alone, but EL type II reduction saves money dollars more than EVAR alone, but EL type II reduction saves money

and time because and time because

we have primary clinical successwe have primary clinical success

we do not have to treat the complications we do not have to treat the complications

we can modify the terms of follow upwe can modify the terms of follow up

Prevention of type II endoleak with biomaterals is Prevention of type II endoleak with biomaterals is

●● SimpleSimple

●● SafeSafe

●● Low costLow cost

●● Independent of stent graft usedIndependent of stent graft used

●● Reduces frequency of Reduces frequency of follow-upfollow-up

●● Increases EVAR successIncreases EVAR success

CONCLUSIONCONCLUSION

DRASTIC DRASTIC TYPE II ENDOLEAKTYPE II ENDOLEAK

REDUCTIONREDUCTION

Manifesting, durable, long lasting, sturdy stabilization of Manifesting, durable, long lasting, sturdy stabilization of whole complex fixed en bloc could probably also reduce the whole complex fixed en bloc could probably also reduce the

incidence of type IA and III endoleaksincidence of type IA and III endoleaks