대한혈관외과학회지 : 제 25 권제 1 호 Vol. 25, No. 1, May 2009 만성동맥폐색증의혈관내치료 대전보훈병원외과 1, 을지대학교의과대학외과학교실 2 김경환 1 ㆍ조병선 2 Endovascular Treatment for Chronic Total Occlusions of Peripheral Arteries Kyoung Hwan Kim, M.D. 1 and Byung Sun Cho, M.D. 2 Department of Surgery, Daejeon Veterans Hospital 1, Eulji University School of Medicine 2, Daejeon, Korea Purpose: The TransAtlantic Inter-Society Consensus offers the proper guidelines for the treatment of peripheral arterial disease (PAD). Many new devices and surgical techniques have been introduced to the medical field and these have been aggressively used to manage the patients with PAD. We performed this study to evaluate the current status of endovascular therapy based on the literature and we review the efficacy and safety of the new devices used in the field. Methods: A search of the literature was performed in the PubMed and science websites. The keywords were chronic total occlusions, superficial femoral artery revascularization, peripheral arterial disease and endovascular therapy. Results: The variation of the results was large according to the studies. The rough technical success rate was 80 90% and the 1 year clinical success rate, the primary patency rate and the limb salvage rate for chronic total occlusions were approximately 50 70%, 50% and 80 90%. The efficacy and safety of the new devices used in the field were acceptable. Conclusion: Further refinement of the guidewires and sheaths and the development of adjunctive devices have allowed traversal of even the long lesions and this has increased the technical success. Although surgery remains the principal treatment for patients with lower limb ischemia, surgeons must now assess the benefits and risks associated with various treatment options, including endovascular therapy. Key Words: Peripheral vascular diseases, Chronic total occlusion, Endovascular treatment 중심단어 : 말초혈관질환, 만성동맥폐색증, 혈관내치료 서 1964년 Dotter와 Judkins(1) 에의해서처음동맥협착에대한풍선확장술이경피적혈관성형술로소개된후풍선확장술은말초혈관질환치료의한양식이되었으며주로파행증환자동맥의부분적협착병변에대하여제한적으로적용되었다. 그러나풍선확장술이가진최소침습적요소, 저렴한초기비용, 입원기간의축소등으로점차많이시행되었다. 여러문헌보고를고찰한최근 론 책임저자 : 조병선, 대전시서구둔산동 1306 302-799, 을지대학병원외과 Tel: 042-611-3064, Fax: 042-259-1111 E-mail: sunjoe@eulji.ac.kr 보고에서말초혈관질환에서시행된풍선확장술은 1년, 3 년, 5년일차개존율이각각 65 72%, 48 66%, 42 55% 이었으며, 스텐트를병행한경우 1년, 3년일차개존율이 76 97%, 60 76% 로비교적좋은성적을보였다 (2). 이에따라최근외과의최소침습수술의증가와더불어혈관외과에서도최소침습수술인혈관내치료가점차증가하고있다 (3). 말초혈관질환에시행된혈관내치료는연구마다폐색의길이, 위치, 모양, 원위부개통된혈관의개수나폐색정도, 환자군의증상등이다르기때문에치료의결과가한결같지않다. Johnston 등 (4) 이보고한결과에의하면협착이있으면서원위부혈관상태가양호한경우 5년임상성공률 ( 임상증상과 ABI의개선 ) 이 53% 이지만폐색이있으면서원위부혈관이좋지않은경우임상성공률 1
2 대한혈관외과학회지 : 제 25 권제 1 호 2009 이 16% 밖에되지않는다. 이와같이선정된환자군에따른결과의편차가심하고새로운기구들의무분별한사용으로인한안정성및효용성의문제로 VIVA Physicians Inc.(5) 에서주도적으로말초혈관질환에서시행되고있는풍선확장술및니티놀 (Nitinol) 스텐트삽입술에대한안정성과효용성의목표치를문헌고찰을통해제시하기도하였다. 결과적으로다양한혈관내치료의결과들이발표되면서말초혈관질환치료의권고안이필요하게되었다. 2000년에 TransAtlantic Inter-Society Consensus (TASC) Working Group이결성되어지금까지보고된문헌을고찰하여말초혈관질환을네군으로분류하여각군에적절한치료안을제시하여향후새로운치료방법의적용시객관적비교가가능하게되었다 (6). 이후여러가지혈관내치료방법및기술의발전으로 2007년 TASC 치료권고안의개정이있었으며개정된 TASC II 에서는혈관내치료가치료방법으로좀더광범위하게적용되었다 (2). 많은비교시험연구들이비교기준으로 TASC 분류를이용하고있으며이를이용하여치료방법간의결과를객관적으로비교하게되었다 (7,8). 현재많은임상시험연구들이진행되고있는데가까운장래에말초혈관질환에대한좀더객관적인치료방침이정해질것으로생각된다. 본연구에서저자들은만성혈관폐색증에서혈관내치료의현재현황과혈관내치료에이용되고있는내막하혈관성형술과눈부시게도입되고있는혈관내치료기구에대해고찰하고자한다. 본론 1) 만성혈관폐색증의혈관내치료현황만성말초혈관폐색의표준치료는혈관우회술이다. TASC II working group(2) 에서발표한자료에의하면자가정맥을이용한대퇴-원위부동맥혈관우회술은 1년, 3년, 5년일차개존율이각각 85%, 80%, 70% 이며, 인조혈관을이용한일차개존율은각각 70%, 35%, 25% 로조사되었다. 이는같은조사에서발표한혈관풍선확장술의 1년, 3년, 5년일차개존율 65 77%, 48 66%, 42 55% 보다자가정맥을이용한혈관우회술이월등히좋은결과를보이고있다. 그러나풍선확장술및니티놀스텐트삽입술을병행한연구에서는 1년, 3년일차개존율은각각 76 97%, 60 76% 로보고하였으며이는무작위전향적연구에의한결과가아니지만좋은결과이며, 혈관내치료가발전하면서수술과대등한결과들도보고되고있다 (9-11). 새로운혈관내치료기구들의개발과발전으로점차혈관내치료의결과가향상되면서표준치료인혈관우회술을대체하려는경향도있다. 수술과풍선확장술을비교한연구들도시행되고있으며대표적인무작위전 향적연구가 Bypass versus Angioplasty in Severe Ischemia of the Leg (BASIL) 시험이다. 이연구에서총 452명의환자가풍선확장술혹은수술군으로배당되었으며이연구의일차목표는하지구제율이었다. 30일사망률은수술군 5%, 풍선확장술군 3% 이며수술군에서합병증이많았다 (57% vs. 41%). 치료비도수술군이더많았으나 3년후조사에서는풍선확장술군의재-중재시술이많아져 (28% vs. 17%) 비용의차이는없어졌다. 2년후각군간하지구제율차이는없었으나 2년후사후비교 (posthoc analysis) 에서는수술군에서통계적으로유의하게사망률이낮았다 (12). Meier(13) 는이연구의결과가수술과풍선확장술의하지구제율에차이가없지만첫째, 수술은정제되고이미성숙한기법인반면혈관내치료는발전과정에있으며아직그기법의표준화도이루어지지않았다. 둘째, BASIL 연구는대상군선정과정에서연구대상군은모두풍선확장술및수술에적합한환자이므로수술이적합하지않은고위험군은빠졌다. 그러나고위험군은혈관내치료가우위를보일수있는군이며이의누락은상대적으로혈관내치료에불리하게작용할수있다. 셋째, 이연구는심각한하지허혈을보인환자를대상으로하여간헐적파행은누락되었다. 혈관내치료가간헐적파행환자에서더좋은성적을보일수있는데또한누락되었다. 이런이유로혈관내치료를우선으로하는치료전략이적어도수술보다우위는아니지만더납득할만한치료전략이아닐까분석하였다. 그러나 Beard(14) 는 BASIL 연구의치료평가종료점 (end point) 에서사망이 75% 나차지하는것을지적하였으며또한위험인자분석이이루어지지않는등연구의문제점을적시하였다. 그리고사후비교의결과를토대로판단하면, 사용가능한정맥이식편을가진적절한환자에서는수술이가장좋은선택이된다고분석하였다. 스텐트그라프트와인조혈관을사용한대퇴-슬관절상부슬와동맥간혈관우회술도비교연구되었는데 Kedora 등 (7) 은최근에시행된무작위연구에서 12개월일차, 이차개존율이각각혈관내치료군이 73.5%, 83.9% 이었으며수술군이 74.2%, 83.7% 로통계적차이가없음을보고하였다. 이상의연구결과를분석하면수술기법보다혈관내치료의발전가능성이많으므로만성혈관폐색증에서도여러기구의개발과기법의발전에따라혈관내치료가치료의우선순위가될가능성이많아졌다. 2) 만성혈관폐색증에서내막하혈관성형술 1989년 Bolia 등 (15) 에의해처음보고된내막하혈관성형술은만성혈관폐색증에대한혈관내치료의적용을증가시켰다. 참내강 (true lumen) 내로재진입을위한기구들의개발과접근경로 (acess) 를오금동맥접근, 경골접근, 족부접근등을통해시도하여혈관내치료의기
Kyoung Hwan Kim and Byung Sun Cho:Endovascular Treatment for Total Occlusion 3 술적성공률이향상되었고, 내막하혈관성형술은전통적으로시행된참내강혈관성형술과비교해서좋은결과등이보고되어말초혈관폐색질환특히만성혈관폐색증에서널리시행되고있다 (8,16). 내막하혈관성형술의원리는의도적으로내막박리를만들어죽상종과같은혈관폐색물질을편심성으로밀어매끄럽고, 병소가없는새로운길을만들어준다 (Fig. 1). 이는동맥내막절제술과비슷한원리이다. 적응증은폐색기간은 3개월이상이좋으며단단하고길이가긴폐색병소일때박리가쉽게일어난다. 혈관천자는보통대퇴골두부의중간부위에서시행하고, 끝이구부러진 4 5 Fr의딱딱한카테터를폐색부위바로위에위치시키고 0.035인치의끝이구부러진친수성유도철사 (guidewire) 을이용하여박리를유도한다. 이때카테터의끝이주위곁가지혈관입구의반대쪽을향하는것이중요하다. Fig. 1. Intentional subintimal angioplasty. 약 10% 에서 20% 내외에서발생하는내막하혈관성형술실패의원인은대부분폐색원위부참내강으로재진입실패이다 (16,17). 또다른내막하혈관성형술의문제는정상혈관으로바로진입하지못하고내막박리면이하부로확대되면서정상혈관의혈류를차단하는것이다. 최근이를위한재진입전용카테터가개발되어해결가능성이높아지고있다. 재진입을위한특수한카테터로혈관내초음파를이용하는 Pioneer catheter (Medtronic, Minneapolis, MN, USA) (Fig. 2), 방사선투시를이용하는 Outback catheter (Cordis Corporation, Miami Lakes, FL, USA) 등이사용되고있다 (Fig. 3). Jacobs 등 (17) 의보고에의하면총 87명의만성혈관폐색증에서내막하혈관성형술시술중재진입의실패가 24예에서발생하였고재진입을위한기구를사용하여 100% 에서혈관내막하시술에성공하였고출혈외에다른합병증은없었다. 내막하혈관성형술의성적을문헌고찰한보고에의하면기술적성공률은 74 92%, 12개월일차개존율은 22 92%, 하지구제율은 50 94% 로보고하고있다 (18). 1966 년부터 2007년 5월까지보고된만성혈관폐색증에시행된내막하혈관성형술을의학자료검색을이용하여분석한결과를보면기술적성공률은약 80 90% 이었으며증상이심할수록, 슬관절이하동맥에시도될수록기술적성공률은낮았다. 1년후 50 70% 에서임상증상의호전이있었다. 1년후일차개존율은약 50% 이었으며하지구제율은약 80 90% 이었다. 연구결과내막하혈관성형술은증상이심각한하지허혈환자에서도좋은결과를보였으며 1년후개존율은떨어지지만비교적높은임상호전과하지구제율을보인다고하였다 (19). 기술적인발전으로기술적성공률및단기개존율이급격히좋아지고있으나장기개존율에있어서는논란이있다 (20). Fig. 2. Pioneer intravascular ultrasound true lumen re-entry catheter. Fig. 3. Outback catheter.
4 대한혈관외과학회지 : 제 25 권제 1 호 2009 Table 1. Minimally invasive treatment options for superficial femoral artery disease Angioplasty +/ stent Cryoplasty Atherectomy Laser-assisted angioplasty Stent grafts Drug-eluting stent 그러나내막하혈관성형술은합병증이낮고, 비용이저렴하며, 시술방법도어렵지않아수술과상호보완적으로일차적으로시행할수있는방법이다. 3) 혈관내치료의새로운기구 만성혈관폐색증시풍선확장술이나단순스텐트 (bare stent) 외다른방법도병행해서많이시도되고있는데냉동풍선확장술 (cryoplasty), 죽상종을기계적으로제거하는방법, 레이저를활용한동맥개통술, 스텐트-그라프트 (stentgraft), 약물코팅한스텐트등이있다 (Table 1). (1) 냉동풍선확장술 : 냉동풍선확장술은 multichannel balloon 내로액체질소가스를넣어부풀려동맥의벽을 10 o 로냉각시켜풍선확장술을시행하는것이다. 작용기전은혈관벽에조절가능한손상을주어혈관벽의손상을최소화하면서혈관을확장시키고또한조직을냉동시켜세포의아포프토시스를유도함으로써민무늬근육세포의증식을최소화하여내막증식증의빈도를획기적으로낮추는것이다 (21). 최근 Laird 등 (9,10) 은기술적성공률 85.3%, 9개월임상개존율 (clinical patency, target lesion revascularization-free) 은 82.2%, 일차개존율 70.1% 로보고하였으며 2006년장기결과보고에서는 3년추적결과 75% 의임상개존율을보고하였다. (2) 죽상제거술 : 죽상종을기계적으로제거하는방법 (mechanical atherectomy) 은 Silverhawk catheter (FoxHollow Technologies Inc., Redwood, CA, USA) 와같은죽상제거카테터 (atherectomy catheter) 를사용하여직접죽상종를제거하는방식이다. 주로심장동맥에이용되어왔으며, 기구가유연하지않고직경이작아서혜부이하혈관에적용할수있다. Zeller 등 (22) 의보고에따르면부가적인시술을많이하였으나 (60% 이상 ) 기술적성공률 86%, 1 년후일차개존율 84% 를보고하였고, Keeling 등 (23) 은기술적성공률 88%, 1년일차개존율 61.7%, 이차개존율 64.1% 로보고하였다. 시술결과가풍선확장술이나스텐트삽입술보다비슷하거나좋지않고기구비용이비싸며긴폐색에서는시술시간이오래걸리고색전의위험때문에색전예방기구를사용해야하는등의단점때문에제한적으로이용되고있다. (3) 레이저혈관성형술 : 레이저를활용한동맥개통술은 308 nm 파장의액시머레이져 (excimer laser) 를쓸수있는 microlaser fiber가장착된카테터로죽상종에대해자외선에너지를전달하여제거시키는방식으로혈관을재개통시킨다 (24). 2006년 Laser Angioplasty for Critical Limb Ischemia (LACI) 다기관시험에서 45% 에서스텐트를병행사용하였으며기술적성공률 86%, 사지구제율 92% 를보고하였다 (25). 대부분단독요법보다는풍선확장술혹은스텐트삽입술과병행하여시행된다. (4) 스텐트-그라프트 : 스텐트-그라프트는이론적으로내부로자라들어올수있는내막증식을그라프트로차단할수있으므로개존율개선을기대하였다. 그러나 Dacron 도포스텐트 (covered stent) 를이용한연구에서스텐트-그라프트설치후설치후증후군 (postimplantation syndrome) 이심하고 2년일차, 이차개존율도각각 17%, 42% 로실망스러운결과를보였다 (26). 이에비하여최근 e-ptfe 도포스텐트 (Viabahn/ Hemobahn endoprosthesis; W.L. Gore, Flagstaff, AZ, USA) 가개발되었고표재성대퇴동맥의폐색질환에적용하여 1년일차개존율 58%, 이차개존율이 73% 로결과가인조혈관을사용한대퇴-슬와동맥우회술와비슷하였다 (27). 가장최근의무작위다기관연구에서 1년일차개존율은 Viabahn이 65%, 일반적인풍선확장술을적용한군에서 40% 로 Viabahn의개존율이유의하게좋았고, 기술적성공률도 95% 대 66% 로스텐트-그라프트군이좋았다고보고하였다 (28). 스텐트-그라프트의단점은기구의직경이커지며단순스텐트에비해비싸며시술후곁가지혈관을폐색시킬수있다는것이다. (5) 약물방출스텐트 (drug-eluting stent): 약물코팅한스텐트는 Rapamycin (sirolimus), Paclitaxel (Taxol) 등의약제를스텐트표면에코팅한스텐트로서내막증식을막아시술후재협착의빈도를줄여주리라기대하여많은시도들이시행되고있다. 코팅된약제는스텐트를설치하는과정에서소실되면안되고, 예측가능하고일정한용량으로방출되어야한다 (29). 1 Rapamycin-eluting stent: 관상동맥에서주로사용되어결과가아주좋았으며말초동맥을대상으로도많은연구가진행되고있다. 표재성대퇴동맥에서약물방출스텐트와단순스텐트를비교한결과, 시술후재협착에서약물방출스텐트군은 22.6%, 단순스텐트군은 30.9% 로약물방출스텐트의협착률이작았으나 2년간관찰한장기추적결과에서는기대와달리단순스텐트군에서재협착율이적게나와더많은임상연구가필요하다 (30,31). 2 Paclitaxel-eluting stent: 관상동맥용 pacilitaxcel-eluting stent를무릎이하의동맥에급성허혈환자에게적용하여기술적성공률 100%, 1년사지구제율 88.5%, 1년일차개존율 30% 로관상동맥용 pacilitaxcel-eluting stent의임상적용의가능성을제시하였으나단순스텐트에비해좋은
Kyoung Hwan Kim and Byung Sun Cho:Endovascular Treatment for Total Occlusion 5 성적을보이지않았다 (32). 초기결과들로볼때말초동맥에서의약물코팅한스텐트의반응은관상동맥과는다른형태를보이며기대했던만큼좋지는못하다. 결 혈관내치료기구의새로운개발과발전으로혈관내치료결과가향상되고있으며 TASC II C, D 병변에서도혈관내치료가가능해졌으며 TASC II 권고안도다시혈관내치료가많이적용되는방향으로개정되리라판단된다. 물론만성혈관폐색증에서혈관우회술과혈관내치료에대한객관적이고전향적인비교가이루어져야겠지만혈관내치료의여러장점때문에향후고위험군에서뿐만아니라모든혈관질환환자의우선치료가혈관내치료가될가능성이많다. 새로운기구및술기에대한부단한습득이필요하며말초혈관질환환자의치료선택시혈관내치료가반드시고려되어야할것으로생각된다. 론 REFERENCES 1) Dotter CT, Judkins MP. Transluminal treatment of arteriosclerotic obstruction: description of a new technic and a preliminary report of its application. Circulation 1964;40: 654-670. 2) Norgren L, Hiatt WR, Dormandy JA, Nehler MR, Harris KA, Fowkes FG; TASC II Working Group. Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). J Vasc Surg 2007;45 Suppl S:S5-S67. 3) Rowe VL, Lee W, Weaver FA, Etzioni D. Patterns of treatment for peripheral arterial disease in the United States: 1996-2005. J Vasc Surg 2009;49:910-917. 4) Johnston KW, Rae M, Hogg-Johnston SA, Colapinto RF, Walker PM, Baird RJ, et al. 5-year results of a prospective study of percutaneous transluminal angioplasty. Ann Surg 1987;206:403-413. 5) Rocha-Singh KJ, Jaff MR, Crabtree TR, Bloch DA, Ansel G; VIVA Physicians, Inc. Performance goals and endpoint assessments for clinical trials of femoropopliteal bare nitinol stents in patients with symptomatic peripheral arterial disease. Catheter Cardiovasc Interv 2007;69:910-919. 6) Dormandy JA, Rutherford RB. Management of peripheral arterial disease (PAD). TASC Working Group. TransAtlantic Inter-Society Consensus (TASC). J Vasc Surg 2000;31:S1-S296. 7) Kedora J, Hohmann S, Garrett W, Munschaur C, Theune B, Gable D. Randomized comparison of percutaneous Viabahn stent grafts vs prosthetic femoral-popliteal bypass in the treatment of superficial femoral arterial occlusive disease. J Vasc Surg 2007;45:10-16. 8) Antusevas A, Aleksynas N, Kaupas RS, Inciura D, Kinduris S. Comparison of results of subintimal angioplasty and percutaneous transluminal angioplasty in superficial femoral artery occlusions. Eur J Vasc Endovasc Surg 2008;36:101-106. 9) Laird J, Jaff MR, Biamino G, McNamara T, Scheinert D, Zetterlund P, et al. Cryoplasty for the treatment of femoropopliteal arterial disease: results of a prospective, multicenter registry. J Vasc Interv Radiol 2005;16:1067-1073. 10) Laird JR, Biamino G, McNamara T, Scheinert D, Zetterlund P, Moen E, et al. Cryoplasty for the treatment of femoropopliteal arterial disease: extended follow-up results. J Endovasc Ther 2006;13 Suppl 2:S52-S59. 11) Schillinger M, Sabeti S, Loewe C, Dick P, Amighi J, Mlekusch W, et al. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N Engl J Med 2006; 354:1879-1888. 12) Adam DJ, Beard JD, Cleveland T, Bell J, Bradbury AW, Forbes JF, et al. Bypass versus angioplasty in severe ischaemia of the leg (BASIL): multicentre, randomised controlled trial. Lancet 2005;366:1925-1934. 13) Meier GH. Current literature for evidence-based infrainguinal endovascular treatment. Semin Vasc Surg 2008;21:210-216. 14) Beard JD. Which is the best revascularization for critical limb ischemia: Endovascular or open surgery? J Vasc Surg 2008; 48:S11-S16. 15) Bolia A, Brennan J, Bell PR. Recanalisation of femoro- popliteal occlusions: improving success rate by subintimal recanalisation. Clin Radiol 1989;40:325. 16) Lipsitz EC, Ohki T, Veith FJ, Suggs WD, Wain RA, Cynamon J, et al. Does subintimal angioplasty have a role in the treatment of severe lower extremity ischemia? J Vasc Surg 2003;37:386-391. 17) Jacobs DL, Motaganahalli RL, Cox DE, Wittgen CM, Peterson GJ. True lumen re-entry devices facilitate subintimal angioplasty and stenting of total chronic occlusions: initial report. J Vasc Surg 2006;43:1291-1296. 18) Lipsitz EC, Veith FJ, Ohki T. Subintimal angioplasty in the management of critical lower-extremity ischemia: value in limb salvage. Perspect Vasc Surg Endovasc Ther 2005;17:11-20. 19) Met R, Van Lienden KP, Koelemay MJ, Bipat S, Legemate DA, Reekers JA. Subintimal angioplasty for peripheral arterial occlusive disease: a systematic review. Cardiovasc Intervent Radiol 2008;31:687-697. 20) Ferreira M, Lanziotti L, Monteiro M, Abuhadba G, Capotorto LF, Nolte L, et al. Superficial femoral artery recanalization with self-expanding nitinol stents: long-term follow-up results. Eur J Vasc Endovasc Surg 2007;34:702-708. 21) Grassl ED, Bischof JC. In vitro model systems for evaluation of smooth muscle cell response to cryoplasty. Cryobiology 2005;50:162-173. 22) Zeller T, RAstan A, Sixt S, Schwarzwälder U, Schwarz T, Frank U, et al. Long-term results after directional atherectomy of femoro-popliteal lesions. J Am Coll Cardiol 2006;48:1573-
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