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Summary

Background/Objective

The aim of this study was to evaluate the technical success rates, primary patency, and complications for TASC C and D aorto-iliac lesions treated by endovascular procedures. Additionally, the influence of the access site and the clinical outcomes were analyzed.

Methods

Between 2008 and 2014, data from 39 patients with 45 chronic iliac artery stenosis and/or occlusion who were treated with endovascular treatment were retrospectively reviewed.

Results

The procedure time was longer for TASC D lesions than for TASC C lesions (163 ± 82 min vs. 105 ± 34 min; p = 0.002), where there was the more common use of brachial and femoral approach simultaneously. There were two perioperative deaths associated with TASC D lesions caused by one iliac artery rupture and one postoperative hospital-acquired pneumonia. The total perioperative complication rate was higher in the TASC D lesions than in TASC C lesions [five (18.5%) vs. zero; p = 0.073]. The corresponding 2-year primary patency rates were 94.9% in TASC C lesions and 88.4% in TASC D lesions. The simultaneous brachial and femoral approach took the longest procedure time (226 ± 157 min).

Conclusion

This study demonstrated that the outcomes of endovascular treatment for TASC C and D aorto-iliac lesions were acceptable, with better technical success in TASC C lesions than in TASC D lesions. Furthermore, the 2-year patency rate for both TASC C and TASC D lesions was acceptable. Additionally, brachial access was useful for complex anatomy, but the failure rate was high.

Keywords

Endovascular procedures;Iliac artery;Trans-Atlantic Inter-Society Consensus (TASC);Patency;Peripheral artery disease

1. Introduction

The long-term durability of open bypass is better than that of endovascular treatment (EVT) for Trans-Atlantic Inter-Society Consensus (TASC) C and D aorto-iliac lesions.1 However, an operative mortality rate of 2.9% and a complication rate of 15.3% make open surgery a less attractive option.

Major changes in the TASC II guidelines in 2007 reflected the rapid growth of EVT, and many centers have reported satisfactory results with EVT for TASC C and D aorto-iliac lesions.2; 3; 4 ;  5 Although the treatment of complex and severe iliac lesions remains challenging, many recently developed devices and a variety of access options have increased success rates.

The aim of this study was to evaluate the technical success rates, primary patency, and complication for TASC C and D aorto-iliac lesions treated by endovascular procedure. Additionally, the influence of the access site and the clinical outcomes were analyzed.

2. Methods

The study was performed in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. This study was approved by Seoul St Marys Hospital Institutional Review Board (KCI 13RISI0908) and patient consent was not needed.

2.1. Patient population

Between 2008 and 2014, data from 39 consecutive patients with 45 chronic iliac artery stenosis and/or occlusion who were treated with EVT were retrospectively reviewed. The TASC II classification of the disease severity for aorto-iliac lesions was used to define the lesion category. The number of patients with TASC C and D lesion morphology was 16 (18 limbs) and 23 (29 limbs), respectively. All patients were judged to be candidates for EVT if they reported disabling claudication, had failed with medical therapy, or had rest pain or gangrene (Fontaine stage IIb∼IV). Endovascular first approach in all patients was the treatment of choice during our study period. Electronic medical records and angiography images were reviewed for demographic data, anatomic lesion, procedural factors, complications, and other outcome variables. Patients with acute limb ischemia, restenotic lesions, diagnostic arteriography, or no intention to treat were excluded.

2.2. Treatment procedure

All patients underwent preoperative ankle-brachial indexes (ABI) and duplex ultrasonography examinations to determine the need for EVT. Aditionally, all patients had at least one radiological imaging, including computed tomography angiography (CTA) or magnetic resonance angiography, before therapeutic angiography. All patients were given 325 mg of oral aspirin prior to the procedure, 325 mg of aspirin and 300 mg of clopidogrel immediately postoperatively, 75mg of clopidogrel for 6 weeks postoperatively, and 100 mg of aspirin indefinitely.

After placing a 6-Fr introducer sheath into the ipsilateral and/or contralateral common femoral artery or a 5-Fr introducer sheath into the left brachial artery, heparin was administered intravenously at a dose of 5000 IU. After completing diagnostic angiography, the lesion was crossed with a guidewire. A 5-Fr straight or slightly curved angiography catheter and a 0.035-in hydrophilic guidewire (Glidewire; Terumo, Tokyo) was used to cross the lesion. In some cases, a hydrophilic guidewire was introduced from the contralateral side, advanced across the occlusion from the aortic side of the iliac artery, and grasped with a snare from the ipsilateral side. If the recanalization attempt failed via these approaches, antegrade recanalization was attempted via the brachial approach. The iliac lesion crossing was achieved in a subintimal or intraluminal manner depending upon the character of the lesion. The length and diameter of the lesion were judged by intraoprative arteriograms. Predilatation of the occlusion before stent deployment was performed at the discretion of the operator. Self-expandable stents for long-segment occlusions or balloon-expandable stents for short-segment occlusions (mostly at the common iliac artery orifice) were preferred. Selection of the stent type and stent size was left to the discretion of the operator. Except for early periods, primary stenting was used in all cases, and the stent diameter ranged from 7–10 mm. Arterial pressure gradient was not considered. Patients were generally discharged within 48 h after the procedure.

2.3. Calcification score

To assess the grade of calcification at the level of the treated iliac artery lesion, axial CTA images were used. Circumferential grade was measured by assessing the presence of calcium in one or more of the four 90 sectors: score 1 (0–90), score 2 (0–180), score 3 (0–270), and score 4 (0–360).

2.4. Technical success

Technical success was defined as <30% residual stenosis on angiography. Procedure-related morbidity and mortality rates within 30 days were determined.

2.5. Follow up

The treated aorto-iliac lesions were assessed by duplex ultrasonography examination, and ABI was measured at 1 month and 6 months during the first postoperative year and annually thereafter. CTA was performed when there were recurrent symptoms, a decrease of ≥0.15 in ABI, and/or an increase of >300 cm/s in the peak systolic velocity.

2.6. Statistical analysis

Comparisons between patients with TASC C lesions and TASC D lesions were performed using the Student t test or Mann-Whitney test for continuous variables and with the Pearson chi-square or the Fisher exact tests for discrete variables as appropriate. The Kolmogorov-Smirnov fit test was performed to ensure normal distribution of the data. Results are reported as mean ± standard deviation for continuous variables or as counts and percentage of patients or lesions for categorical data. A p < 0.05 was considered significant. Comparisons between approaches were done with the Kruskal-Wallis test for continuous variables and by linear association for discrete variables. Primary patency of the percutaneous transluminal angioplasty site was analyzed using the Kaplan-Meier analysis with the log-rank test applied. The SPSS software program (version 18; SPSS Inc, Chicago, IL, USA) was used for all statistical analyses.

3. Results

3.1. Patients

Baseline demographic and clinical data for the two groups are shown in Table 1. The baseline characteristics of both groups were comparable, except for smoking and coronary artery disease. The more commonly associated comorbidity in patients with TASC D lesions was coronary artery disease (30.4%; p = 0.029).

Table 1. Demographic/clinical characteristics.
Total (n=39 patients) TACS C (n=16) TASC D (n=23) p
Age (mean) 72.9 ± 8.3 73.5 ± 7.8 72.4 ± 8.8 0.712
Gender (Male) 31 (79.4%) 11 (68.7%) 20 (86.9%) 0.235
BMI 22.0 ± 3.3 21.2 ± 3.6 22.8 ± 2.9 0.140
Smoking 20 (51.2%) 5 (31.2%) 15 (65.2%) 0.037
Diabetes mellitus 17 (43.5%) 6 (37.5%) 11 (47.8%) 0.522
Hypertension 29 (74.3%) 11 (68.7%) 18 (78.2%) 0.711
Dyslipidemia 16 (41%) 6 (37.5%) 10 (43.4%) 0.709
Coronary artery disease 7 (17.9%) 0 7 (30.4%) 0.029
Cerebrovascular disease 6 (15.3%) 0 6 (26.0%) 0.064
Renal insufficiency (Cr > 1.2) 5 (12.8%) 1 (6.2%) 4 (17.3%) 0.631
COPD 3 (7.6%) 1 (6.2%) 2 (8.6%) ns
Laboratory findings
 Total cholesterol 169 ± 44 169 ± 46 168 ± 42 0.961
 LDL cholesterol 100 ± 29 97 ± 25 103 ± 34 0.580
 HDL cholesterol 38 ± 10 41 ± 12 35 ± 8 0.171
 Triglyceride 155 ± 104 140 ± 109 170 ± 100 0.441
 Creatinine 0.97 ± 0.28 0.93 ± 0.21 1.01 ± 0.36 0.444
ASA score 0.377
 1 3 (8.1%) 2 (12.5%) 1 (4.7%)
 2 25 (67.5%) 12 (75%) 13 (61.9%)
 3 9 (24.3%) 2 (12.5%) 7 (33.3%)
Limb side
 Right 25 (64.1%) 10 (62.5%) 15 (65.2%) 0.862
 Lleft 20 (51.2%) 8 (50.0%) 12 (52.1%) 0.894
 Both 6 (15.3%) 2 (12.5%) 4 (17.3%) ns
Fontaine stage
 IIb 22 (56.4%) 11 (68.7%) 11 (47.8%) 0.195
 III 9 (23.0%) 2 (12.5%) 7 (30.4%) 0.262
 IV 9 (23.0%) 4 (25.0%) 5 (21.7%) ns
Post-procedural medications
 Aspirin 32 (82.0%) 12 (75.0%) 20 (86.9%) 0.415
 Clopidogrel 15 (38.4%) 5 (31.2%) 10 (43.4%) 0.440
 Cilostazol 19 (48.7%) 10 (62.5%) 9 (39.1%) 0.151
 Wafarin 4 (10.2%) 3 (18.7%) 1 (4.3%) 0.286
 Berasil 4 (10.2%) 1 (6.2%) 3 (13.0%) 0.631
 Statin 29 (74.3%) 10 (62.5%) 19 (82.6%) 0.264

ASA = American Society of Anesthesiologists; BMI = body mass index; COPD = chronic obstructive pulmonary disease; Cr = creatine; HDL = high-density lipoprotein; LDL = low-density lipoprotein; ns = not significant; TASC = Trans-Atlantic Inter-Society Consensus.

3.2. Clinical outcome

A total of 47 limbs (39 patients) had been evaluated with anatomic variables, access site, and time of procedure (Table 2). Most of the patients were treated for claudication (57.7%). Occlusion was higher in TASC D lesions than in TASC C lesions, but statistical significance was not achieved (61.1% vs. 85.1%, p = 0.086). Bilateral iliac artery occlusions were observed in six patients, four of which were in TASC D lesions. The procedure time was longer for TASC D lesions than for TASC C lesions (163 ± 82 min vs. 105 ± 34 min; p = 0.002), where there was more common use of the brachial and femoral approach simultaneously. A variety of stents were used in 100% of TASC C lesions and in 85.1% of TASC D lesions (p = 0.138).

Table 2. Lesion characteristics and summary of results.
Total (n=47 limbs) TACS C (n=18 limbs) TASC D (n=29 limbs) p
Indication for treatment
 Claudication 26 (57.7%) 12 (66.6%) 14 (51.8%) 0.324
 Resting pain 9 (20%) 2 (11.1%) 7 (25.9%) 0.279
 Minor tissue loss 10 (22.2%) 4 (22.2%) 6 (22.2%) ns
Occlusion 34 (75.5%) 11 (61.1%) 23 (85.1%) 0.086
Stump 34 (75.5%) 15 (83.3%) 19 (70.3%) 0.482
Aneurysm 1 (2.2%) 1 (5.5%) 0 0.400
Calcification score
 1 16 (36.3%) 3 (17.6%) 13 (48.1%) 0.118
 2 16 (36.3%) 9 (52.9%) 7 (25.9%) ns
 3 10 (22.7%) 3 (17.6%) 7 (25.9%) < 0.001
 4 2 (4.5%) 2 (11.7%) 0 0.041
Infrainguial lesion
 A 10 (22.2%) 5 (27.7%) 5 (18.5%) 0.489
 B 4 (8.8%) 2 (11.1%) 2 (7.4%) ns
 C 4 (8.8%) 2 (11.1%) 2 (7.4%) ns
 D 5 (11.1%) 1 (5.5%) 4 (14.8%) 0.634
Initial technical success rates 42 (93.3%) 18 (100.0%) 24 (88.8%) 0.264
Procedure time 134 ± 58 105 ± 34 163 ± 82 0.002
Stenting 41 (91.1%) 18 (100.0%) 23 (85.1%) 0.138
 Diameter (max) 8.5 ± 1.0 8.2 ± 1.0 8.9 ± 1.0 0.157
 Total length 150 ± 56 128 ± 36 173 ± 76 0.242
 Number of stent 1.7 ± 1.1 1.4 ± 0.9 2.0 ± 1.2 0.128
Initial access
 Ipsilateral 6 (13.3%) 4 (22.2%) 2 (7.4%) 0.199
 Counterlateral 15 (33.3%) 7 (38.8%) 8 (29.6%) 0.519
 Only brachial 9 (20%) 2 (11.1%) 7 (25.9%) 0.279
 Bifemoral 12 (26.6%) 5 (27.7%) 7 (25.9%) ns
 Brachial & Femoral 3 (6.6%) 0 (0.0) 3 (11.1%) 0.264
Pre ABI 0.49 ± 0.20 0.53 ± 0.19 0.45 ± 0.21 0.229
Post ABI 0.89 ± 0.18 0.91 ± 0.17 0.87 ± 0.19 0.459
Complications 5 (11.1%) 0 5 (18.5%) 0.073
Procedure time 134 ± 58 105 ± 34 163 ± 82 0.002

ABI = ankle-brachial index; ns = not significant; TASC = Trans-Atlantic Inter-Society Consensus.

3.3. Complications

There were two perioperative deaths in the TASC D lesion group, with the causes being one iliac artery rupture and one postoperative hospital acquired pneumonia. The total perioperative complication rate was higher in the TASC D lesion group than in the TASC C lesion group [five (18.5%) vs. zero; p = 0.073]. These complications included one distal embolization, two iliac artery ruptures, one aspiration pneumonia, and one myocardial infarction. One out of five TASC D patients who failed technically was treated with bifemoral bypass, two required medication only, and the remaining two could not receive additional treatment due to complications.

3.4. Patency

The corresponding 2-year primary patency rates were 94.9% for TASC C lesions and 88.4% for TASC D lesions (Figure 1); however, there was no statistically significant difference between the groups considering the primary patency. TASC D lesions were reanalyzed to assess whether a stent had been inserted. The stent-inserted group had superior patency (log rank test = 0.012).


Primary patency curve for TASC C and D lesions. TASC = Trans-Atlantic ...


Figure 1.

Primary patency curve for TASC C and D lesions. TASC = Trans-Atlantic Inter-Society Consensus.

3.5. Access site

The calcification score was higher in the patients treated via the simultaneous brachial and femoral approach (3 ± 0.0; p < 0.001), and the simultaneous brachial and femoral approach took the longest procedure time (226 ± 157 min; Table 3). Of the three simultaneous brachial and femoral approach cases, only one was technically successful. In the two failed approaches, patients expired due to iliac artery rupture, while the successfully treated patient was transferred due to nosocomial pneumonia infection.

Table 3. Comparison by approach.
Total (n=45 limbs) Ipsilateral (n=6 limbs) Counterlateral (n=15 limbs) Only brachial (n=9 limbs) Bifemoral (n=12 limbs) Brachial & Femoral (n=3 limbs) p
TASC C 18 (40.0%) 4 (66.6%) 7 (46.6%) 2 (22.2%) 5 (41.6%) 0 0.122
TASC D 27 (60.0%) 2 (33.3%) 8 (53.3%) 7 (77.7%) 7 (58.3%) 3 (100.0%) 0.122
Right 25 (55.5%) 5 (83.3%) 8 (53.3%) 6 (66.6%) 6 (50.0%) 0 0.098
Left 20 (44.4%) 1 (16.6%) 7 (46.6%) 3 (33.3%) 6 (50.0%) 3 (100.0%) 0.098
Occlusion 34 (75.5%) 4 (66.6%) 14 (93.3%) 7 (77.7%) 6 (50.0%) 3 (100.0%) 0.383
Stump 34 (75.5%) 5 (83.3%) 11 (73.3%) 8 (88.8%) 9 (75.0%) 1 (33.3%) 0.383
Aneurysm 1 (2.2%) 1 0 0 0 0 0.200
Calcification Score 2.1 ± 0.5 1.8 ± 0.4 2.1 ± 0.5 2.0 ± 0.0 2.4 ± 0.6 3 ± 0.0 < 0.001
Infrainguial lesion
 A 10 (22.2%) 3 (50.0%) 3 (20.0%) 1 (11.1%) 3 (25.0%) 0 0.291
 B 4 (8.8%) 0 2 (13.3%) 0 2 (16.6%) 0 0.829
 C 4 (8.8%) 0 2 (13.3%) 1 (11.1%) 1 (8.3%) 0 ns
 D 5 (11.1%) 0 1 (6.6%) 3 (33.3%) 0 1 (33.3) 0.554
Technical success 42 (93.3%) 5 (83.3%) 15 (100.0%) 9 (100.0%) 12 (100.0%) 1 (33.3) 0.220
Complication rates 5 (11.1%) 0 1 (6.6%) 1 (11.1%) 1 (8.3%) 2 (66.6) 0.067
Procedure time 140 ± 72 101 ± 30 139 ± 72 169 ± 44 118 ± 63 226 ± 157 < 0.001

TASC = Trans-Atlantic Inter-Society Consensus.

4. Discussion

This study demonstrated a 100% technical success rate and a 94.4% primary patency at 2 years for TASC C lesions and an 88.8% technical success rate and 88.4% primary patency at 2 years for TASC D lesions. The complication rate was 0% for TASC C lesions and 18.5% for TASC D lesions.

The TASC II guidelines in 2007 recommended surgical bypass for TASC C and D aorto-iliac lesions. It stated “Endovascular methods do not yield good enough results to justify them as primary treatment” for TASC D lesions, and “Open revascularization produces superior long-term results”, and “Endovascular methods should only be used when there is a high risk associated with open repair” for TASC C lesions.1

However, major changes were made between the TASC I and TASC II classification, and more vascular surgeons are attempting to treat TASC C and TASC D lesions with EVT.1 ;  6 Moreover, technical and device improvements have encouraged vascular surgeons to perform EVT for TASC C or TASC D aorto-iliac lesions during the last 10 years. Considering the 93.3% technical success rate in this study, the results are high compared with those of TASC A and TASC B lesions treated by EVT.7 Additionally, easy-to-repeat procedures for re-stenosis constitute one reason for the increasing trend for EVT.

In this study, only left brachial artery accesses were performed in two limbs (22.2%) in TASC C lesions and in seven limbs (77.7%) in TASC D lesions. Brachial access is widely used in coronary interventions, but much less so in noncoronary interventions. The main reasons for reluctant use of brachial access are complications, such as hematoma and arterial thromboembolism. These complications were reported in 6% to 8% of cases.8 ;  9 We performed brachial access using the Seldinger technique in all patients, and performed surgical closure after making a small incision. There were no complications related to the use of brachial access. The brachial approach offered a better pushability in complex endovascular procedures, while the surgical cut-down method can also be used safely.8

Both intraluminal endovascular interventions and subintimal angioplasty can be appled to treat iliac chronic total occlusionlesions. There was no difference in the primary patency (74% for the intraluminal approach and 76% for subintimal angioplasty at the 3-year follow up).10 ;  11.

We prefer primary stenting in TASC C and D aorto-iliac lesions. AbuRahma et al.12 reported an overall early clinical success rate of 93% for primary stenting and 46% for selective stenting in TASC C and TASC D iliac lesions.12 A 2-year primary patency rate of 94.4% in TASC C lesions and 88.4% in TASC D lesions in this study was comparable with previous reports.

The technical success rate was higher in TASC C lesions than in TASC D lesions, and complications were fewer in TASC C lesions than in TASC D lesions. In a meta-analysis, comparing TASC C lesions and TASC D lesions, no significant difference was found between the two groups when considering technical success.13 Other factors may have played a role in the patients as important as the length of the occlusion.14 ;  15 Due to potential differences in patient selection, a direct comparison of these results was not possible.

Our study had some limitations. All data analyzed were retrospective, although it was a prospective data collection that originated from only two institutions. The techniques, equipment, and experience of the surgeons also changed during data collecting. This may have resulted in an overestimation of the technical success rate.

5. Conclusion

This study demonstrated that the outcomes of EVT for TASC C and D aorto-iliac lesions were acceptable, with better technical success in TASC C lesions than in TASC D lesions. Furthermore, the 2-year patency rate for both TASC C and TASC D lesions was acceptable, and brachial access was useful for complex anatomy, although with a high failure rate.

References

  1. 1 L. Norgren, W.R. Hiatt, J.A. Dormandy, M.R. Nehler, K.A. Harris, F.G. Fowkes; Inter-Society consensus for the management of peripheral arterial disease (TASC II); J Vasc Surg, 45 (Suppl S) (2007), pp. S5–67
  2. 2 F.C. Carnevale, M. De Blas, S. Merino, J.M. Egana, J.G. Caldas; Percutaneous endovascular treatment of chronic iliac artery occlusion; Cardiovasc Intervent Radiol, 27 (2004), pp. 447–452
  3. 3 R. Gandini, S. Fabiano, M. Chiocchi, R. Chiappa, G. Simonetti; Percutaneous treatment in iliac artery occlusion: long-term results; Cardiovasc Intervent Radiol, 31 (2008), pp. 1069–1076
  4. 4 C.H. Timaran, T.L. Prault, S.L. Stevens, M.B. Freeman, M.H. Goldman; Iliac artery stenting versus surgical reconstruction for TASC (Trans-Atlantic Inter-Society Consensus) type B and type C iliac lesions; J Vasc Surg, 38 (2003), pp. 272–278
  5. 5 S. Yilmaz, T. Sindel, E. Luleci; Subintimal versus intraluminal recanalization of chronic iliac occlusions; J Endovasc Ther, 11 (2004), pp. 107–118
  6. 6 J.A. Dormandy, R.B. Rutherford; Management of peripheral arterial disease (PAD). TASC Working Group. Trans-Atlantic Inter-Society Consensus (TASC); J Vasc Surg, 31 (2000), pp. S1–S296
  7. 7 Galaria II, M.G. Davies; Percutaneous transluminal revascularization for iliac occlusive disease: long-term outcomes in Trans-Atlantic Inter-Society Consensus A and B lesions; Ann Vasc Surg, 19 (2005), pp. 352–360
  8. 8 J.A. Alvarez-Tostado, M.A. Moise, J.F. Bena, et al.; The brachial artery: a critical access for endovascular procedures; J Vasc Surg, 49 (2009), pp. 378–385
  9. 9 S.D. Heenan, S. Grubnic, T.M. Buckenham, A.M. Belli; Transbrachial arteriography: indications and complications; Clin Radiol, 51 (1996), pp. 205–209
  10. 10 B.L. Chen, H.R. Holt, J.D. Day, C.L. Stout, G.K. Stokes, J.M. Panneton; Subintimal angioplasty of chronic total occlusion in iliac arteries: a safe and durable option; J Vasc Surg, 53 (2011), pp. 367–373
  11. 11 V.S. Kashyap, M.L. Pavkov, J.F. Bena, et al.; The management of severe aortoiliac occlusive disease: endovascular therapy rivals open reconstruction; J Vasc Surg, 48 (2008), pp. 1451–1457
  12. 12 A.F. AbuRahma, J.D. Hayes, S.K. Flaherty, W. Peery; Primary iliac stenting versus transluminal angioplasty with selective stenting; J Vasc Surg, 46 (2007), pp. 965–970
  13. 13 W. Ye, C.W. Liu, J.B. Ricco, K. Mani, R. Zeng, J. Jiang; Early and late outcomes of percutaneous treatment of Trans-Atlantic Inter-Society Consensus class C and D aorto-iliac lesions; J Vasc Surg, 53 (2011), pp. 1728–1737
  14. 14 A. Koizumi, H. Kumakura, H. Kanai, et al.; Ten-year patency and factors causing restenosis after endovascular treatment of iliac artery lesions; Circ J, 73 (2009), pp. 860–866
  15. 15 U. Ozkan, L. Oguzkurt, F. Tercan; Technique, complication, and long-term outcome for endovascular treatment of iliac artery occlusion; Cardiovasc Intervent Radiol, 33 (2010), pp. 18–24
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