Endovascular infrainguinal revascularization: predictive factors for patency

Abstracts

Contexto: A terapia endovascular tem avançado muito como tratamento para a doença arterial oclusiva infrainguinal, principalmente com o desenvolvimento dos materiais e dos stents autoexpansíveis de nitinol. Objetivo: Avaliar os resultados e os fatores determinantes da angioplastia fêmoro-poplítea em pacientes portadores de isquemia de membros inferiores. Métodos: Foram tratados, através de angioplastia com ou sem stent, 114 pacientes, e acompanhados por um período médio de 12 meses. A média de idade foi de 66 anos; 53% eram do sexo feminino; 23,7% eram portadores de claudicação incapacitante; 8,8%, de dor isquêmica de repouso; e 67,5%, de lesão trófica. As lesões foram classificadas segundo o TransAtlantic Inter-Society Consensus II em A (53%), B (34%), C (5%) e D (9%). Resultados: A análise angiográfica do leito distal mostrou uma média de 1,4±1,0 artérias infrapoplíteas pérvias. O sucesso inicial foi de 97%. No seguimento de 1, 6, 12 e 24 meses, a perviedade primária foi de 94, 78, 48 e 31%, e a primária assistida, de 94, 84, 73 e 61%, respectivamente (p = 0,005). O leito distal pobre e a presença de diabetes melito foram associados a uma menor perviedade primária (p = 0,01), enquanto a extensão da lesão não influenciou os resultados. As taxas de salvamento de membro em 6, 12 e 24 meses foram de 95, 90 e 90%, respectivamente. Conclusões: A extensão das lesões tratadas não foi um fator determinante em nossa casuística para o menor sucesso da angioplastia, o que pode sugerir que as indicações para o tratamento endovascular possam ser ampliadas para pacientes com lesões TransAtlantic Inter-Society Consensus II C/D.

Artéria femoral; artéria poplítea; angioplastia com balão; arteriosclerose obliterante

ORIGINAL ARTICLE

Endovascular infrainguinal revascularization: predictive factors for patency

Felipe Nasser^I; Seleno Glauber de Jesus Silva^II; Rodrigo Bruno Biagioni^II; Roberta Cristina de Almeida Campos^II; Marcelo Calil Burihan^II; Rhumi Inoguti^II; Melissa Andreia de Moraes^III; Orlando da Costa Barros^III; José Carlos Ingrund^IV; Adnan Neser^V

^I

^IIAssistant vascular surgeon, Vascular Surgery Service, HSM, São Paulo, SP, Brazil

^IIIAssistant vascular surgeon, Department of Vascular Ultrasonography, HSM, São Paulo, SP, Brazil

^IVSupervisor, Vascular Surgery Service, HSM, São Paulo, SP, Brazil

^VSupervisor, Vascular Surgery Service, HSM, São Paulo, SP, Brazil

^{Correspondence}

ABSTRACT

Background: Endovascular techniques have undergone major advances with regard to the treatment of infrainguinal arterial occlusive disease, mainly as a result of development of new devices and self-expanding nitinol stents.

Objective: To evaluate the results and determinant factors of femoropopliteal angioplasty in patients with critical lower limb ischemia.

Methods: During the study, 114 patients were submitted to angioplasty or stenting and followed during an average of 12 months. Mean age was 66 years, and 53% were female; 23.7% presented disabling claudication, 8.8% ischemic rest pain and 67.5% tissue loss. Lesions were classified as A (53%), B (34%), C (5%) and D (9%) according to the TransAtlantic Inter-Society Consensus II.

Results: Angiographic run-off analysis showed an average of 1.4±1.0 patent infrapopliteal artery. Initial success rate was 97%. At 1, 6, 12 and 24 months of the follow-up period, primary patencies of 94, 78, 48 and 31%, and assisted primary patencies of 94, 84, 73 and 61% were achieved (p = 0.005). Poor run-off and diabetes mellitus were directly associated with lower primary patency rates (p = 0.01), while angiographic severity of the lesions did not influence results. Limb salvage rates calculated at 6, 12 and 24 months were 95, 90 and 90%, respectively.

Conclusions: Lesion length was not a determinant factor of lower success rates for angioplasty or stenting, which may suggest that indications for endovascular treatment can be extended to patients with TransAtlantic Inter-Society Consensus II C/D lesions.

Keywords: Femoral artery, popliteal artery, balloon angioplasty, arteriosclerosis obliterans.

Introduction

Infrainguinal peripheral occlusive atherosclerotic disease (POAD) may lead to intermittent claudication or even to critical ischemia with occurrence of ulcers. The basic treatment for cases of intermittent claudication is still control of risk factors and walking exercises, while revascularization is reserved for cases of ischemic rest pain (IRP) or ulcers.¹ Despite low complication rates in the infrainguinal territory, primary patency rates of percutaneous transluminal angioplasty (PTA), either with or without stent implantation, studies published in the early decade led to reservation of such modality for patients with short lesions, high surgical risk or those without autogenous conduit. However, with the technological development of recanalization materials and self-expandable nitinol stents, indication of such modality has been growing over the past years.² The new publication by the TransAtlantic Inter-Society Consensus (TASC)³ already determined femoropopliteal endovascular therapy as established and favorite modality for cases of stenoses of occlusions lower than 10 cm in extension.

This study aims at reviewing short- and medium-term results of endovascular treatment in the femoropopliteal segment in patients with POAD and identifying factors that might influence such results.

Method

From January 2004 to May 2007 (41 months), 116 percutaneous revascularizations were performed in the femoropopliteal segment of 114 patients with critical lower limb ischemia, representing a prospective analysis of case series. Indication of endovascular treatment was based on clinical evaluation and angiographic assessment. Exclusion criteria were urgent need of revascularization, presence of not feasible limb, lesions in other vascular segments that are not native arteries and non-dialytic renal failure.

Record was performed about patients' demographic data, comorbidities, clinical category according to recommendations of the Society for Vascular Surgery/International Society for Cardiovascular Surgery (SVS/ISCS)⁴ and anatomical category according to TASC⁵ as well as ankle-brachial index (ABI) before and after the procedure. After the end of the study period, all lesions were reclassified according to TASC II.³ Classification of distal bed was performed by angiographic analysis and counting the number of patent infrapopliteal arteries, with direct or indirect formation of plantar arch, according to the parameters published by Suroviec et al.⁶

Procedures were performed at an angiology and radiology center equipped with digital subtraction device and low-osmolarity non-ionic contrast. Vascular access was performed by contralateral anterograde or retrograde puncture of the common femoral artery using a 6F sheath, according to proximal or distal level of the lesion, followed by endovenous systemic heparinization (5,000 IU in bolus, plus 1,000 IU/h 2 hours after the procedure). All patients were previously using platelet antiaggregating drugs and maintained association of AAS 200 mg/day with ticlopidine (500 mg/day) or clopidogrel (75 mg/day) for at least 30 days, after which they used only one drug. After lesion transposition by conventional technique under road mapping, with 0.014'', 0.018'' or 0.035'' hydrophilic guide-wires, ATP was properly performed with conventional balloon catheters, compatible with lesion extension, using 5-15 atm pressures for 45 seconds. Primary or selective use of stents was based on lesion location or extension, presence of occlusion, elastic recoil larger than 30% or dissection of treated area. In case of long occlusions, more than one stent was used.

During outpatient follow-up, surveillance was performed by clinical examination, ABI measurement, color Doppler ultrasound every 1, 3, 6, 12, 18 and 24 months and thigh x-rays in two incidences for detection of stent fractures. In case there were signs of clinical worsening, with fall of at least one category of SVS/ISCS classification, reduction of at least 0.1 in ABI value or identification by color Doppler ultrasound of pre-, intra- or post-stent stenosis larger than 50% (characterized as systolic index > 2.5),⁷ patients were submitted to new angiography and simultaneous treatment of the identified lesion, following the techniques described above.

Statistical analysis used Kaplan-Meier method and Log-Rank to calculate patency and survival and Cox regression to define risk factors relative to time using the SPSS 13.0 software. Patency results followed SVIR recommendations for devices of peripheral arterial revascularization.⁸

Results

A total of 114 patients were submitted to femoropopliteal endovascular revascularization (53% were females). Demographic data and clinical indication for intervention are shown in Table 1.

Distribution of affected vessels was initially classified according to TASC,⁵ with the following values for each group: A = 26%, B = 29%, C = 37% and D = 8%. In January 2007, a new publication updated the classification for infrainguinal lesions (TASC II),³ widening anatomical indications for endovascular treatment (TASC A and B). A reclassification of all patients was then performed, and a new distribution was obtained for each group: A = 52%, B = 34%, C = 5% and D = 9%, as shown in Figure 1.

Initial technical success, considered as lesion transposition, angioplasty and/or stent placement with residual stenosis < 30%, was obtained in 97% of cases. Complications (dissection of treated area, hematoma at the puncture site, stent fracture and death) are listed in Table 2. There were no deaths directly caused by the endovascular procedure, but by cardiovascular or infectious complications related to the ulcer. Self-expandable nitinol stents accounted for 70%, while balloon angioplasties were performed in 15% of cases. Balloon-expandable stents were only used over the first years of the study; in the last 2 years only nitinol stents were used.

Primary patency, assisted patency, secondary patency and limb salvage values were obtained during the 2-year follow-up for each patient. At 1, 6, 12 and 24 month interval, primary patency was 94, 78, 48 and 31%, and assisted patency was 94, 84, 73 and 61%, respectively (Log-Rank; p < 0.05), while secondary patency was 95, 90, 83 and 80% (p < 0.001), as shown in Figures 2 and 3. Limb salvage rate, considered as amputation equal or lower than transmetatarsal level enabling walking was 95, 90 and 90% in 6, 12 and 24 months, respectively, as shown in Figure 4.

Analysis of distal bed revealed mean 1.4±1.0 of patent infrapopliteal arteries, with the following percentage distribution: 0 = 25%, 1 = 35%, 2 = 23% and 3 = 17%. Presence of proper distal bed (> 1 artery) determined a larger primary patency over 2 years (p = 0.027), according to Figure 5.

Cox regression statistics for variables related to time showed that only presence of diabetes mellitus and a poor distal bed had a negative influence on primary patency (Table 3).

Discussion

Although femoropopliteal arterial segment represents more than 50% of POAD cases, decision about type of ideal treatment remains complex. In cases of critical ischemia, endovascular treatment has replaced surgical revascularization in high-surgical-risk patients, while in patients with intermittent claudication it has been often used in association with clinical treatment alone.⁹

For at least one decade, published data on efficacy and patency were not satisfactory, partly due to the unique characteristics of superficial femoral artery disease,⁹ as well as isolated use of balloon angioplasty^10,11 or Palmaz balloon-expandable stents.^12,13

The continuous technological evolution of materials has not allowed a precise comparison between different groups of patients treated over the years. However, many studies (BLASTER, Mewissen, RESILIENT and SIROCCO I e II)¹⁴ have shown superiority of new generation of nitinol stent. Such advancement is followed by complications detectable during longer follow-up of such patients, such as fracture and intrastent restenosis.

Schlager et al.¹⁵ showed a higher intrastent restenosis rate using Wallstent in relation to nitinol stents and a large difference in fracture rates, even between both groups of nitinol stents - SMART (Cordis) and Dynalink/Absolute (Guidant). On the other hand, the multi-center study RESILIENT, in its 6 first months, showed encouraging data (2.2% of fracture, 84.4% of primary patency, with 2/3 of arteries calcified and mean 1.8 stents implanted per patient).¹⁶ Similarly, Schillinger et al.^17.18 have shown good results with primary use of self-expandable stent in comparison with its selective use.

Primary patency and assisted primary patency values (Figure 2) at 1 year (48 and 73%, respectively) are lower than those found in recent studies (about 75 and 85%, according to the methodology used).^2,3,6,19 This is probably due to the fact that, over the first years of the study, most stents available for use were little flexible (steel and Elgiloy^®), which were progressively replaced by nitinol stents.

As an attempt to follow the evolution of indication of endovascular treatment in the femoropopliteal segment, we proposed to reclassify lesions for TASC II (2007), which is considered as the standard to group patients in many published clinical trials. The data obtained (Figure 1) show that most lesions had their indications widened to classes A and B (endovascular treatment of choice or preference), resulting in a large number of angioplasties in long lesions/occlusions, which were directly considered for surgical revascularization. In a retrospective study recently published, Ihnat et al.²⁰ reviewed cases of femoropopliteal angioplasty using TASC II and obtained similar results to ours, even for a sample mainly comprised of claudication patients.

Many studies have tried to relate patency values of angioplasties with varied risk factors involved. Presence of diabetes mellitus, poor distal bed, renal failure, long occlusive lesions and critical ischemia is associated in the literature with reduced patency in the medium and long term,^1,2,6,20-23 while others did not find an accurate relation.¹⁹ Our findings showed that only diabetes mellitus and poor distal bed (absence of patent infrapopliteal artery) influenced the outcome in a 1-year follow-up.

On the other hand, lesion extension was not a determining factor for worse outcome. This is probably due to the fact that most patients in our sample had critical ischemia, certainly with extensive and multisegmental lesions (76%), opposed to many studies that showed a higher rate of claudicating patients (about 60%).^2,6,20,24,25 Therefore, angioplasty should be performed in patients with longer lesions, including classes C and D of TASC II, as maintenance of patency and adequate limb salvage (Figure 4) are possible. This is particularly important for patients with high surgical morbidity and mortality rates or absence of available autogenous conduit.

Some studies reinforce the good response of primary stent implantation, with fewer reinterventions and higher patency.¹⁸ We believe such tactics is efficient, especially in long occlusions. High patency reported in our series regarding TASC D lesions can be mainly explained by the high rate of elderly and fragile patients, in whom ulcers and baseline diseases prevent full limb mobility and, consequently, stent fracture. It is worth stressing the low incidence of claudicating patients in this study (23.7%) compared to other studies published in the literature (about 60%).

It can be perceived that TASC enhancement and increase in its endovascular indication reflect the new percutaneous revascularization techniques, new available materials and results of the medium- and long-term follow-up, usually comparable with conventional surgery. However, some questions raised in the literature about long-term results still need to be answered. Could the high rates of occlusion/restenosis and reintervention in class D lesions be better avoided using primary conventional surgery? Would patients with major tissue loss and poor distal bed be better treated with primary amputation or with percutaneous procedures of multisegmental revascularization?²⁰

A possible limitation of this study is the great sample variability, involving comorbidities associated with a wide spectrum of clinical status. In addition, over the years, progress of the endovascular technology available in the market has prevented a standardization of materials for the treatment of atherosclerotic occlusive lesions, which may have biased the results.

Perhaps the main differentials of medium- and long-term results of the endovascular treatment are proper surveillance and reintervention. Serial clinical examination, ABI calculation and color Doppler ultrasound, as long as routinely used in the follow-up of such patients, enabled to reach assisted primary patency and secondary patency rates similar to those reported in the literature.^1,2 Such post-angioplasty follow-up is justified as many patients would eventually be submitted to limb amputation.

Conclusions

Femoropopliteal angioplasty can be performed with acceptable initial success and patency in the short and medium term, as long as proper surveillance and reintervention are established. Absence of diabetes mellitus and presence of at least one patent infrapopliteal artery were the factors that influenced the higher success rate of this treatment. Extension of treated lesions, however, was not a determining factor in this sample for a lower success rate of angioplasty, which may suggest that indications for endovascular treatment can be extrapolated to patients with TASC II C/D lesions. For that reason, it was clear that the new publication by TASC definitely consolidated and widened indication of endovascular treatment in the femoropopliteal segment. It is now necessary to wait to know whether the endovascular treatment of infrainguinal lesions will be restricted to stent implantation or whether new technologies (cutting-balloon, cryoplasty, endolaser, covered stents, pharmacological stents, etc.)^14,26 can satisfactorily increase the number of options. Two recent publications have raised such issue by reporting results much similar to those of conventional angioplasty using covered stent (Viabhan, Gore)²⁷ and pharmacological stent (Zilver PTX, Cook)²⁸ in the treatment of relatively short lesions of the superficial femoral artery. Impossibility of performing experimental studies and constant production of new materials will certainly never allow us to define the gold standard endovascular treatment for any vascular segment, but will help to define the best and least invasive treatment available so far.

References

Manuscript received August 14, 2008, accepted December 9, 2008.

This study was presented as special paper at the 37th Brazilian Congress of Angiology and Vascular Surgery, held in September 2007 in Goiânia (GO).

No conflicts of interest declared concerning the publication of this article.

• 1. Black JH 3rd, LaMuraglia GM, Kwolek CJ, Brewster DC, Watkins MT, Cambria RP. Contemporary results of angioplasty-based infrainguinal percutaneous interventions. J Vasc Surg. 2005;425:932-9.
• 2. Conrad MF, Cambria RP, Stone DH, et al. Intermediate results of percutaneous endovascular therapy of femoropopliteal occlusive disease: A contemporary series. J Vasc Surg. 2006;44:762-9.
• 3. Norgren L, Hiatt WR, Dormandy JA, et al. Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC II). J Vasc Surg. 2007;45:S5-67.
• 4. Rutherford RB, Baker JD, Ernst C, et al. Recommended standards for reports dealing with lower extremity ischemia: Revised version. J Vasc Surg. 1997;26:517-38.
• 5. Management of peripheral arterial disease (PAD). TransAtlantic Inter-Society Consensus (TASC). Eur J Vasc Endovasc Surg. 2000;19:Suppl A:Si-xxviii, S1-250.
• 6. Surowiec SM, Davies MG, Eberly SW, et al. Percutaneous angioplasty and stenting of the superficial femoral artery. J Vasc Surg. 2005;41:269-78.
• 7. Ascher E, Marks NA, Hingorani AP, Schutzer RW, Mutyala M. Duplex-guided endovascular treatment for occlusive and stenotic lesions of the femoral-popliteal arterial segment: a comparative study in the first 253 cases. J Vasc Surg. 2006;44:1230-8.
• 8. Sacks D, Marinelli DL, Martin LG, Spies JB, Society of Interventional Radiology Technology Assessment Committee. Reporting standards for clinical evaluation of new peripheral arterial revascularization devices. J Vasc Interv Radiol. 2003;14:S395-404.
• 9. Jaff M. The nature of SFA disease. Endovasc Today. 2004;4:13-15.
• 10. Golledge J, Ferguson K, Ellis M, et al. Outcome of femoropopliteal angioplasty. Ann Surg. 1999;229:146-53.
• 11. Stanley B, Teague B, Raptis S, Taylor DJ, Berce M. Efficacy of balloon angioplasty of the superficial femoral artery and popliteal artery in the relief of leg ischemia. J Vasc Surg. 1996;23:679-85.
• 12. Cejna M, Thurnher S, Illiasch H, et al. PTA versus Palmaz stent placement in femoropopliteal artery obstructions: a multicenter prospective randomized study. J Vasc Interv Radiol. 2001;12:23-31.
• 13. Pozzi Mucelli F, Fisicaro M, Calderan L, et al. Percutaneous revascularization of femoropopliteal artery disease: PTA and PTA plus stent. Results after six years' follow-up. Radiol Med. 2003;105:339-49.
• 14. Laird J. Interventional options in the SFA. Endovasc Today. 2004(Suppl):9-12.
• 15. Schlager O, Dick P, Sabeti S, et al. Long-segment SFA stenting--the dark sides: in-stent restenosis, clinical deterioration, and stent fractures. J Endovasc Ther. 2005;12:676-84.
• 16. Laird JR. The RESILIENT Trial Update: 6-Months Phase 1 Results. Endovasc Today. 2005:29-36. http://www.evtoday.com/PDFarticles/1005/EVT1005_JohnR.Laird,Jr,MD.html
• 17. Schillinger M, Sabeti S, Loewe C, et al. Balloon angioplasty versus implantation of nitinol stents in the superficial femoral artery. N Engl J Med. 2006;354:1879-88.
• 18. Schillinger M, Sabeti S, Dick P, et al. Sustained benefit at 2 years of primary femoropopliteal stenting compared with balloon angioplasty with optional stenting. Circulation. 2007;115:2745-9.
• 19. Vogel TR, Shindelman LE, Nackman GB, Graham AM. Efficacious use of nitinol stents in the femoral and popliteal arteries. J Vasc Surg. 2003;38:1178-84.
• 20. Ihnat DM, Duong ST, Taylor ZC, et al. Contemporary outcomes after superficial femoral artery angioplasty and stenting: The influence of TASC classification and runoff score. J Vasc Surg. 2008;47:967-74.
• 21. Clark TW, Groffsky JL, Soulen MC. Predictors of long-term patency after femoropopliteal angioplasty: Results from the STAR registry. J Vasc Interv Radiol. 2001;12:923-33.
• 22. Sabeti S, Mlekusch W, Amighi J, Minar E, Schillinger M. Primary patency of long-segment self-expanding nitinol stents in the femoropopliteal arteries. J Endovasc Ther. 2005;12:6-12.
• 23. Dick F, Diehm N, Galimanis A, Husmann M, Schmidli J, Baumgartner I. Surgical or endovascular revascularization in patients with critical limb ischemia: influence of diabetes mellitus on clinical outcome. J Vasc Surg. 2007;45:751-61.
• 24. Ferreira M, Capotorto LF, Giafar Abuhadba, Marcelo Monteiro, Luiz Lanziotti. Recanalização da artéria femoral superficial com stents Zilver: técnica padronizada e análise retrospectiva de 3 anos. J Vasc Bras. 2006;5:263-70.
• 25. Krankenberg H, Schlüter M, Steinkamp HJ, et al. Nitinol stent implantation versus percutaneous transluminal angioplasty in superficial femoral artery lesions up to 10 cm in length: the femoral artery stenting trial (FAST). Circulation. 2007;16:285-92.
• 26. Leguizamón, JH. Angioplastia de las arterias infrainguinales: cuando el objetivo es preservar la integridad física, anatómica y funcional. Rev Arg Cardiol. 2003;71:157-8.
• 27. Saxon RR, Dake MD, Volgelzang RL, Katzen BT, Becker GJ. Randomized, multicenter study comparing expanded polytetrafluoroethylene covered endoprosthesis placement with percutaneous transluminal angioplasty in the treatment of superficial femoral artery occlusive disease. J Vasc Interv Radiol. 2008;19:823-32.
• ²⁸
  Endovascular Today News [site na Internet]. Acessado: 24/08/08. Disponível em: http://www.evtoday.com/eNews/eNews062408.html
  » link

Correspondence:

Felipe Nasser

Rua Santa Marcelina, 177

CEP 08270-070 - São Paulo, SP, Brazil

Tel.: [phone]

Publication Dates

• Publication in this collection
  26 May 2009
• Date of issue
  Mar 2009

History

• Accepted
  09 Dec 2009
• Received
  14 Aug 2008