The procedure of non-ruptured abdominal aortic aneurysm endoluminal repair is described. The first two procedures in Croatia by use of an AneuRx stent graft were performed in two patients admitted to the Division of Vascular Surgery, Sestre milosrdnice University Hospital in Zagreb. To our knowledge, these were the first self-supporting procedures carried out in Croatia. The principal characteristics of endoluminal material and equipment as well as their use are presented. Preoperative diagnostic procedures and postoperative course in the two patients are also described. Special emphasis is given to the indications and contraindications for this type of procedure as well as to the major possible complications. Endoluminal repair for aortic aneurysm is a new and revolutionary approach to the treatment of this serious and severe illness. Endovascular surgery is expected to mark the first decade of the new millennium.Prikazan je postupak endoluminalne rekonstrukcije nerupturirane aneurizme abdominalne aorte. Operacije je izvedena u dvojice bolesnika na Odjelu za vaskularnu kirurgiju Kliničke bolnice “Sestre milosrdnice” u Zagrebu, upotrebom AneuRx stent grafta. Prema našim spoznajama, operacija je prvi put samostalno učinjena u Hrvatskoj. Prikazana su glavna obilježja materijala i uređaja te njihova primjena. Također se daje prikaz prijeoperacijske dijagnostike i poslijeoperacijskog tijeka u dvojice operiranih bolesnika. Navedene su indikacije i kontraindikacije za primjenu postupka, kao i glavne moguće komplikacije. Endoluminalni način u liječenju aneurizme abdominalne aorte predstavlja nov i revolucionaran pristup, primjena kojega će doći do izražaja u prvom desetljeću novoga tisućljeća

Drago De Syo

Ivo Despot

Ivo Lovričević

Marijan Lovrenčić

Vladimir Tonković

Zdenko Novotny

English

HRČAK - Portal of Croatian Scientific and Professional Journals

Acta clin Croat 2000; 39:121-126 Preliminary communication121FIRST EXPERIENCES IN ENDOLUMINAL REPAIR OFABDOMINAL AORTIC ANEURYSM USING BIFURCATEDSTENT GRAFTIvo LovriËeviÊ1,Vladimir TonkoviÊ2, Ivo Despot1, Drago DeSyo1, Marijan LovrenËiÊ2 and ZdenkoNovotny31Division of Vascular Surgery, Department of Surgery, 2Department of Radiology, and 3Department of Anesthesiology,Sestre milosrdnice University Hospital, Zagreb, CroatiaSUMMARY - The procedure of non-ruptured abdominal aortic aneurysm endoluminal repair isdescribed. The first two procedures in Croatia by use of an AneuRx stent graft were performed intwo patients admitted to the Division of Vascular Surgery, Sestre milosrdnice University Hospital inZagreb. To our knowledge, these were the first self-supporting procedures carried out in Croatia.The principal characteristics of endoluminal material and equipment as well as their use are pre-sented. Preoperative diagnostic procedures and postoperative course in the two patients are also de-scribed. Special emphasis is given to the indications and contraindications for this type of procedureas well as to the major possible complications. Endoluminal repair for aortic aneurysm is a new andrevolutionary approach to the treatment of this serious and severe illness. Endovascular surgery isexpected to mark the first decade of the new millennium.Key words: Aortic aneurysm, abdominal; Aortic aneurysm,  abdominal - surgery; Stents; Tomography, x-ray- computedCorrespondence to: Ivo LovriËeviÊ, M.D.,M.S., Division of VascularSurgery, Department of Surgery, Sestre milosrdnice University Hos-pital, Vinogradska c. 29, HR-10000 Zagreb, CroatiaReceived May 25, 1999, accepted in revised April 14, 2000IntroductionAbdominal aortic aneurysm (AAA) is the most com-mon atherosclerotic aortic disease, the incidence of whichhas been on a constant rise for the past three decades1. Bydefinition, AAA is a permanent local widening of the lu-men surpassing the normal diameter by at least 50%, lo-cated between the renal arteries and the aortic bifurcation2.The disease is most commonly found in the older age group,more commonly in males than in females, and it is encoun-tered in 3 to 6 per cent of the population over 652,3.The first surgical repair was performed by Dubost4.Since that first surgical procedure, the mortality rate of theelectively operated patients has been constantly decreasing,owing to improved surgical and anesthesiology practicesand techniques. Currently, the mortality rate is between 3and 5 per cent of the total number of surgically treatedpatients. However, the mortality due to aneurysm rupturein surgically treated patients is high and exceeds 50%.The new, endoluminal approach was first seen in thework of Parodi et al. 19915, and has gradually paved its wayto daily surgical practice as a minimally invasive surgicalprocedure. AAA endoluminal repair is currently used in theUnited States and western Europe. The first Croatian at-tempts in the use of the technique are described, brieflypresenting the information available.There are several models of different stent grafts. Themost commonly used models are Meadox Vanguard Graft,World Medical Talent Graft and Medtronic AneuRxGraft, the latter used in the two cases presented, and manyothers.I. LovriËeviÊ et al. Endoluminal repair of abdominal aneurysm122 Acta clin Croat, Vol. 39, No. 2, 2000Subjects and MethodsAsymptomatic aneurysms were diagnosed in twomales aged 52 and 64 years. Their ultrasound findingsshowed aneurysmal widening with the longest diameterof 4.5 and 6 centimeters, respectively. The indications forendovascular operation were made in the same way asthose for open surgical repair of AAA. A criterion for theuse of this technique was morphological possibility to useendoprosthesis.Standard preoperative diagnosis included computedtomography (CT) in 5-mm slices, including the area fromthe suprarenal level down to the iliac arteries, and arteri-ography. The purpose of the diagnostic procedures was toobtain a detailed insight into the morphology of the aortaand its branches, with special reference to the position ofthe renal arteries and the length of the aortic neck. Anotherimportant aspect to take in consideration was the structureof the iliac arteries, i.e. their angulations and narrowings.Finally, the preoperative CT scans and arteriography read-ings enabled us to determine the length and width of theaorta and iliac arteries, necessary for selection of an appro-priate stent graft.The patients were operated on under endotracheal an-esthesia and systemic heparinization of 100 mg per kg bodyweight. The operative procedure exposed both groins, i.e.common femoral arteries with their branches. Intraopera-tive arteriography was performed, and stent grafts wereplaced by means of an intra-arterial conductor and insertedby means of a delivery catheter. In both patients, bifurcatedstent grafts measuring 26x15 mm, 16.5 cm long, wereplaced.The intraoperative course was uneventful in both pa-tients. The loss of blood did not exceed 200 mL. The du-Fig. 1. Angiography and CT scans of patient 1: infrarenal abdominal aortic aneurysm with largest diameter of 4.5 cm.Fig. 2. Angiography and CT scans of patient 2: saccular aneurysm with largest diameter of 6 cm.I. LovriËeviÊ et al. Endoluminal repair of abdominal aneurysmActa clin Croat, Vol. 39, No. 2, 2000 123ration of each surgical procedure was approximately 2 hoursand 30 minutes.The postoperative course also proceeded uneventfully.The patients were discharged from the hospital on day 7after abdominal CT scanning which showed the positionof the stent grafts and which would have revealed any pos-sible endoleaks. CT scans showed that both stent graftswere well placed, and there was no internal hemorrhage orendoleaks.The main characteristic of the stent grafts chosen inthese two cases is that they are made from woven thin-wallpolyester, reinforced by nitinol stent which self-expandswhen exposed to high temperature. The graft is insertedinto the ‘delivery catheter’ in which it is compressed, andthis is how it is introduced into the artery. Stent grafts areavailable in five different size combinations, and their bi-furcated diameters range from 20x12 mm to 28x16 mm.The first figure represents the diameter of the aortic seg-ment, and the second one is the diameter of the iliac seg-ment. A special attachment for the other leg has to be ofthe same iliac dimension. The standard device includes cuffsfor the aortic and iliac segments. The grafts are supplied intwo different lengths, 13.5 and 16.5 cm.Surgical procedure requires special equipment whichincludes introducers, guides and catheters, i.e. all equipmentneeded for intraoperative arteriography and radiology in-terventions. In addition, the following devices, included inthe AneuRx Endovascular Delivery System, are needed forthe graft insertion: rapid track introducer sheath; deliverycatheter; and deployment handle.The delivery of the graft is performed in a surgicallysterile operating room environment, enabling intraopera-tive diascopy and arteriography. Surgical staff are ready forpossible conversion into open surgical repair.By means of the above mentioned equipment, a bifur-cated graft stent is placed between the infrarenal part of theaorta up to the bifurcation of the common iliac artery, thetwo representing the two fixed attachment zones. Theinfrarenal aortic neck should be approximately 2 cm long,and definitely not shorter than 1 cm. Due to its structure,i.e. its mobility and partial adaptability, the graft is adapt-able to the arterial structure in the area of the non-fixedattachment zones.During the placement of the graft, radiopaque markerpoints, co-ordinated with preoperative and intraoperativearteriography and diascopy on the x-ray monitor, serve fororientation.Fig. 3. Patient 1 postoperative CT scan: right position of the iliacsegment of the prosthesis; no endoleak was observed.Fig. 4. Patient 2 postoperative CT scan: right position of infrarenal and iliac prosthesis; no endoleak was observed.I. LovriËeviÊ et al. Endoluminal repair of abdominal aneurysm124 Acta clin Croat, Vol. 39, No. 2, 200050% of all abdominal aneurysms can be managed in thisway.Contraindications for the placement of an endolumi-nal stent graft include the restrained use of x-ray in somepatients, and signs of a systemic infection for the manage-ment of elective hemodynamically significant aneurysms.A rational indication for the treatment of AAA eitherby open or by endovascular surgery may be based on thepremise that the mortality associated with this mode oftreatment is lower than the risk of rupture within one year8.In recent studies, the early mortality of endovascular AAArepair varied from 0 to 6.6%9. A few studies comparingpatients treated with stent grafts with a contemporary con-trol patient group treated by open surgery showed no dif-ference in the mortality10,11.At the same time, the main advantages of endovascularprocedure include lower incidence of systemic complica-tions, faster recovery, and reduced hospital stay.Given the loss of blood of not more than 100-200 mLand the fact that the operative procedure itself takes ap-proximately 2 hours under epidural anesthesia, it is obvi-ous that this type of surgical repair should be adopted asthe method of choice in high-risk patients. The main dis-advantage of the procedure is the high cost of stent graftand need of long-term follow-up by imaging techniques,because of the risk of the occurrence of late endoleak.Nowadays, the matter of interest mostly are bifurcatedgrafts because of a number of problems associated with theuse of tubular grafts. The number of AAAs with a suffi-ciently long segment of normal dimensions above the aor-tic bifurcation, which is a precondition for the placementof a tubular graft, is rather low. On the other hand, the ab-dominal aorta is usually distinctly calcified and of an ellip-tic shape in this bifurcated segment, hence it is often thesite of endoleak12,13.The success of the graft placement and the rate of com-plications are not presented in statistical terms because ofthe short time elapsed, since these grafts were actuallyplaced for the first time and their number was too small(n=2) for any statistical analysis to perform. However, ini-tial reports from other studies indicate that the graft deliv-ery was associated with a very low rate of complications re-quiring conversion. Thus, in a series of 113 endoluminalgrafts placed in Sydney in 199714, intraoperative conver-sion was required in 18 patients. The Medtronic trainingcenter in Peruggia reports on only one conversion in 150patients. Similar data, with an ever lower relative numberof conversions, have been communicated directly by Dr.Moll from Niuewegein, the Netherlands.Fig. 5. Right position of the prosthesis at the end of the procedure.DiscussionThe AAA rupture is a well known phenomenon in sur-gical practice with a high mortality rate. It requires a verydemanding surgical treatment, associated with a number ofcomplications during the intra- and postoperative course,and a very uncertain outcome. On the other hand, it is alsoknown that the 5-year survival rate of non-surgically treatedpatients with hemodynamically significantly enlarged an-eurysms is less than 20%, and that the prognosis for theelectively operated patients is much more favorable, with a5-year survival rate of 64%6,7. These facts point to the sig-nificance of the problem as well as to the inevitability ofsurgical intervention.The indications for endoluminal procedure are the sameas for the elective surgical treatment, and include aneurysmsof more than 5 cm in diameter, aneurysms between 4 and5 cm in diameter with a documented increase of 0.5 cm inthe past 6 months, and aneurysms of an eccentric shape,however, these give rise to the question whether small an-eurysms should be considered for surgical treatment in agreat number of cases, because this less hazardous and lessinvasive approach would prevent their further growth.There also are some morphological preconditions for theuse of endoluminal stent graft. They primarily include theabove mentioned sufficiently long infrarenal aneurysmneck, which should be approximately 2 cm long and notmore than 24 mm wide. Another precondition is the pa-tency of iliac arteries, i.e. the absence of narrowings of lessthan 6 mm in diameter. In practice, this means that 30%-I. LovriËeviÊ et al. Endoluminal repair of abdominal aneurysmActa clin Croat, Vol. 39, No. 2, 2000 125In all reports, the so-called endoleak, i.e. bleedingwithin the aneurysm sac close to the graft inserted, is themost commonly described complication. The reports dif-ferentiate between primary ‘endoleak’, observed during thesurgical repair, and secondary endoleak, detected on sub-sequent diagnostic procedures13,15,16. This complicationmay lead to the aneurysm growth and rupture.The Eurostar Register has been established in Europein order to come up with some conclusions which wouldbe common to all European centers for endovascular sur-gery13.This study included data on more than 1000 patientsin total.The most common complication, endoleak, is seen in5% to 44% of patients. Although a half of them stop spon-taneously, there have been some proposals for endovascularand surgical management of this complication.Another parameter followed by the Eurostar Registeris the dynamics of the possible aneurysm growth. Despitethe placement of endoluminal grafts, aneurysm continuesto grow in 11% of patients who also have endoleaks.Endovascular repair is most probably a breakthrough inthe treatment of AAA. Although still in an initial stage, itis gaining an ever more important place in the treatmentof this serious condition due to its non-invasiveness and lowintraoperative morbidity rate. It may be expected that thefuture use will lead to improvements in the technical char-acteristics of stent grafts and delivery materials as well asin the placement of grafts and management of complica-tions, thus making it possible to evaluate the procedure andassess its benefits over a longer period of time.References1. NEVIT MP, BALLARD DJ, HALLET JW. Prognosis of ab-dominal aortic aneurysms. A population based study. N Engl J Med1989;321:109-14.2. BENGTSSON H, BERQUIST D, EKBERG O, JANZON L. Apopulation based screening of abdominal aortic aneurysms (AAA).Eur J Vasc Surg 1991;5:53-7.3. BENGTSSON H, BERQUIST D, STERNBY NH. Increasingprevalence of abdominal aortic aneurysms. A necropsy study. EurJ Surg 1992;158:19-23.4. DUBOST C. Resection of an aneurysm of the abdominal aorta -re-establishment of the continuity by preserved human arterialgraft with results after 5 months. Arch Surg 1952;64:405-8.5. PARODI JCL, PALMAZ JCL, BARONE HD. Transfemoral in-traluminal graft implantation for abdominal aortic aneurysm. AnnVasc Surg 1991;5:491-9.6. ERNST C. Abdominal aortic aneurysm. N Engl J Med1993;328:1167-72.7. POLTERAURER P, PRAGER M, HLEZENBEIN T. Dacron vsPTFE in aortoiliacal reconstruction: results of prospective rando-mised trial. Surgery 1992;111:626-33.8. SCOTT RAP, TISI PV, ASHTON HA, ALLEN DR. Abdomi-nal aortic aneurysm rupture rates: a 7 year follow up of the entireabdominal aortic aneurysm population detected by screening. J VascSurg 1998;28:13-20.9. CUYPERS Ph, BUTH J, HARRIS PL, GEVERS EL. On behalfof Eurostar Collaborators. Realistic expectations for patients withstent-graft treatment of abdominal aortic aneurysms. Results ofEuropean Multicentre Registry. Eur J Vasc Endovasc Surg1999;17:507-16.10. MAY J, WHITE GH, YU W. Concurrent comparison of endolu-minal versus open repair in the treatment of abdominal aortic an-eurysms: analysis of 303 patients by life table method. J Vasc Surg1998;27:213-21.11. ZARINS CK, WHITE RA, SCHWARTEN D, KINNEY E,DIETRICH EB, HODGSON KJ, FOGARTY TJ. For investi-gators of the Medtronic AneuRx Multicenter Clinical Trial, Stan-ford, California. AneuRx stent graft versus open surgical repair ofabdominal aortic aneurysms: multicenter prospective clinical trial.J Vasc Surg 1999;29:292-308.12. COLBURN MD, MOORE WS. Endovascular repair of abdomi-nal aortic aneurysms using the EGS tube and bifurcated graft sys-tem. World J Surg 1996;20:664-72.13. MOORE WS, RUTHEFORD RB. Transfemoral endovascularrepair of abdominal aortic aneurysm: results of the North Ameri-can EVT phase I trial. J Vasc Surg 1996;23:543-53.14. MAY J, WHITE GH, WAUGH W, YU R, STEPHEN M,SINEURAINE K, HARRIS P. Conversion from endoluminal toopen repair of abdominal aortic aneurysms: a hazardous procedure.Eur J Vasc Endovasc Surg 1997;14:4-11.15. HARRIS PL, BUTH J, MIALHE C, MYHRE H, NORGRENL.The need for clinical trials of endovascular abdominal aortic stent/graft repair; the Eurostar project. J Endovasc Surg 1997;4:72-9.16. WAIN GH, MARIN ML, OHKI T, SANCHEZ LA, LYON RT,ROZENBLIT A, SUGGS WD, YUAN JG, VEITH FJ. Endo-leaks after endovascular graft treatment of aortic aneurysms: clas-sification, risk factors an outcome. J Vasc Surg 1998;27:69-80.I. LovriËeviÊ et al. Endoluminal repair of abdominal aneurysm126 Acta clin Croat, Vol. 39, No. 2, 2000SaæetakPRVA ISKUSTVA U ENDOLUMINALNOJ REKONSTRUKCIJI ANEURIZME ABDOMINALNE AORTEUZ UPOTREBU BIFURKACIJSKE PROTEZEI. LovriËeviÊ, V. TonkoviÊ, I. Despot, D. DeSyo, M. LovrenËiÊ i Z. NovotnyPrikazan je postupak endoluminalne rekonstrukcije nerupturirane aneurizme abdominalne aorte. Operacije je izvedenau dvojice bolesnika na Odjelu za vaskularnu kirurgiju KliniËke bolnice “Sestre milosrdnice” u Zagrebu, upotrebom AneuRxstent grafta. Prema na¹im spoznajama, operacija je prvi put samostalno uËinjena u Hrvatskoj. Prikazana su glavna obiljeæjamaterijala i ureðaja te njihova primjena. Takoðer se daje prikaz prijeoperacijske dijagnostike i poslijeoperacijskog tijeka udvojice operiranih bolesnika. Navedene su indikacije i kontraindikacije za primjenu postupka, kao i glavne moguÊekomplikacije. Endoluminalni naËin u lijeËenju aneurizme abdominalne aorte predstavlja nov i revolucionaran pristup,primjena kojega Êe doÊi do izraæaja u prvom desetljeÊu novoga tisuÊljeÊa.KljuËne rijeËi: Aneurizma aorte, abdominalna; Aneurizma aorte, abdominalna - kirurgija; Stent; Tomografija, radiografija -kompjutorizirana

Prva iskustva u endoluminalnoj rekonstrukciji aneurizme abdominalne aorte uz upotrebu bifurkacijske proteze

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Prva iskustva u endoluminalnoj rekonstrukciji aneurizme abdominalne aorte uz upotrebu bifurkacijske proteze

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