Abstract
Background:
There are limited data comparing the outcomes of subintimal vs. intraluminal approach in the treatment of long femoropopliteal artery occlusions. The objective of this study was to investigate the efficacy and safety of the subintimal approach for long femoropopliteal artery occlusions.
Methods and Results:
From a multicenter retrospective registry cohort, we included a total of 461 patients with 487 femoropopliteal artery occlusions classified as Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) II C/D for this analysis. We compared the immediate and mid-term outcomes of subintimal vs. intraluminal approaches. There were 228 patients with 243 limbs in the subintimal group, and 233 patients with 244 limbs in the intraluminal group. Baseline clinical and lesion characteristics were comparable between the 2 groups. The technical success rate was significantly higher in the subintimal group than in the intraluminal group (95.1% vs. 89.8%, P=0.041). The clinical primary patency (67.5% vs. 73.4% at 12 months, 54.0% vs. 61.3% at 24 months; P=0.086) and target lesion revascularization (TLR)-free survival (89.5% vs. 86.3% at 12 months, 77.6% vs. 76.0% at 24 months; P=0.710) did not differ significantly between the subintimal and the intraluminal groups.
Conclusions:
In long femoropopliteal occlusions, the subintimal approach achieved a higher technical success rate and similar mid-term primary patency and TLR-free survival compared with intraluminal approach.
The femoropopliteal artery is the longest arterial segment that is exposed to various forces induced by leg movements and frequently affected by the atherosclerotic process. Over the past decade, self-expanding nitinol stents have significantly improved the outcomes of endovascular therapy for femoropopliteal artery disease;1
however, the technical success and durability of patency after endovascular treatment in this arterial segment have been challenged by common lesion characteristics, such as long occlusions and calcifications.2
The subintimal approach is a technique that recanalizes a totally occluded segment via intentional creation of a subintimal channel. Since this approach was first described by Bolia et al in 1989,3
the subintimal approach has been widely used to overcome long chronic arterial occlusions.2,4–6
Furthermore, the more recent introduction of re-entry devices and the adoption of bidirectional wiring approaches have improved the technical success of the subintimal approach for femoropopliteal lesions.7
In addition, implantation of self-expanding nitinol stents further contributes to increased patency rates after this procedure.1,7–9
Despite these recent advances in the outcomes of the subintimal approach, there is still concern about the durability of the subintimally created channel. Most of the previous studies on the subintimal approach have been single-center retrospective studies with relatively small numbers of patients.10
Furthermore, there are only limited data comparing the outcomes of the subintimal vs. intraluminal approach in the treatment of long femoropopliteal artery occlusions. Thus, in the present study, we sought to investigate the immediate and mid-term outcomes of the subintimal approach for the treatment of femoropopliteal chronic occlusion by analyzing data from a multicenter registry cohort.
Methods
Study Population
The Korean Vascular Intervention Society (K-VIS) Endovascular therapy in Lower Limb Artery diseases registry (ELLA) is a multicenter observational study with retrospective and prospective cohorts of patients with lower extremity artery disease treated with endovascular therapy (ClinicalTrials.gov NCT02748226). The retrospective patient cohort consisted of 3,434 patients with 5,097 affected limbs treated between January 2006 and July 2015 in 31 Korean hospitals.11
Inclusion criteria were: age ≥20 years, and lower extremity artery disease treated with endovascular therapy. Acute limb ischemia, Buerger’s disease, repeated revascularization after the first index procedure, and patients without procedural, in-hospital, or first clinical follow-up data were excluded. We further excluded patients (n=3) treated with drug-coated balloons, which have shown superior outcomes than plain conventional balloons in terms of primary patency and target lesion revascularization (TLR)-free survival.12
There were no cases of treatment with drug-eluting stents or interwoven nitinol stents. From this registry population, the present study analyzed a total of 461 patients (487 limbs) with the Inter-Society Consensus for the Management of Peripheral Arterial Disease (TASC) II C or D de novo femoropopliteal artery occlusions (Figure 1). Data for patients’ baseline clinical and lesion characteristics, medications at hospital discharge, clinical status at follow-up, and non-invasive and invasive investigations were collected from their electronic medical records. The study was conducted in accordance with the Declaration of Helsinki and approved by the institutional review boards of the participating hospitals. The associated institutional review boards waived the requirement for informed consent for this retrospective study.
Dual-antiplatelet therapy (aspirin 100 mg/day and clopidogrel 75 mg/day) was administered prior to the index procedure. All procedures were performed under local anesthesia and supplemented with intravenous sedation and analgesia when required. Systemic heparin (5,000 units) was administered to achieve an activated clotting time >250 s. Either ipsilateral or contralateral femoral puncture was performed, depending on the distance to the target lesion.
The choice of intraluminal or subintimal approach was left to the operator’s discretion. For the intraluminal approach, various 0.014-, 0.018-, and 0.035-inch guidewires were chosen according to lesion characteristics and operator’s preference. For the subintimal approach, 0.018- or 0.035-inch hydrophilic guidewires were used to create the subintimal channel. The tip of the wire was introduced into the subintimal channel to form a loop and advanced distally with support of a 4–5Fr catheter or a microcatheter until the wire re-entered the true lumen at the distal stump. We considered wire passage to be subintimal when the tip of the advanced wire formed a loop and when linear or spiral dissections were visible at the proximal and distal stumps. In cases of difficult re-entry, a re-entry device (Outback Ltd., Cordis, Bridgewater, NJ, USA) was used to achieve wire passage into the true lumen. The Outback Re-entry catheter has been available in Korea since December 2009.
When antegrade passage of wires was not feasible, an additional retrograde approach was attempted through pedal or tibial artery puncture. After crossing the target lesion with wires, predilatation was routinely performed. Lesions with residual stenosis >30% or flow-limiting dissections after predilatation required stent implantation. Choice of self-expanding nitinol stents (SMART [Cordis]; Zilver [Cook, Bloomington, IN, USA]; Absolute Pro [Abbott Vascular, Redwood City, CA, USA]; Complete SE, [Medtronic, Santa Rosa, CA, USA]; or Protégé Everflex [Covidien, Plymouth, MN, USA]) was made at the operator’s discretion. Deployed stents were routinely dilated with balloons for better apposition. After the procedure, patients routinely received aspirin (100 mg/day) lifelong and clopidogrel (75 mg/day) or cilostazol (200 mg/day) for at least 1 month. All patients were followed clinically at 1 month and every 3–6 months thereafter. Ankle-brachial index (ABI) was evaluated at 1-year intervals or if the symptom status deteriorated. At least 1 imaging study, such as CT angiography, duplex ultrasound, or intra-arterial angiography, was performed in the event of either a >0.15 decrement in the ABI or worsening symptoms that were reflected by changes in the Rutherford category.
Study Endpoints and Definitions
Primary endpoint was clinical primary patency at 1 year, which was defined as absence of significant restenosis (>50%) on imaging studies or symptom aggravation by Rutherford category with decrease in the ABI >0.15. Restenosis was defined by peak systolic velocity index (ratio of intrastenotic peak systolic velocity to prestenotic velocity) <2.4 by duplex ultrasound. The secondary endpoint was clinically driven TLR-free survival. TLR was defined as any surgical or percutaneous intervention at the target lesion after the index procedure. All clinically driven TLR was performed for restenotic lesions with both worsening symptoms and >0.15 decrease in the ABI. Poor run-off was defined as absence of patent (luminal stenosis <50%) infrapopliteal run-off vessels. Technical success was defined as recanalization of the target lesion in the absence of residual stenosis >30% or flow-limiting dissection. A major complication was defined as any event that was either fatal or required surgical management or rehospitalization within 30 days of the procedure.
Statistical Analysis
Continuous variables are presented as mean±standard deviation and were compared using Student’s t-test for parametric data and the Mann-Whitney test for nonparametric data. Categorical variables are presented as number (percentage) and were compared using the chi-square test or Fisher›s exact test. Clinical primary patency and TLR-free survival were analyzed using Kaplan-Meier survival curves, and the log-rank test was used to compare outcomes between the patient groups. Univariate Cox proportional hazards regression analyses using baseline clinical, lesion, and procedural variables were performed to identify factors associated with restenosis. The variables achieving a P-value <0.10 in the univariate analysis and variables that are considered clinically important were evaluated in the multivariate analysis model to determine the independent predictors of restenosis. All statistical analyses were performed using R version 3.3.2 (http://www.r-project.org/). P<0.05 was considered statistically significant.
Results
Baseline Clinical and Lesion Characteristics
There were no significant differences in the clinical characteristics of the 2 groups (Table 1), although the subintimal group tended to be prescribed statins less frequently (64.0%) than the intraluminal group (72.5%, P=0.063). There was no significant difference in the use of dual (aspirin and clopidogrel) or triple (aspirin, clopidogrel, and cilostazol) antiplatelet therapy. Lesion characteristics and procedural data of the treated patients are presented in
Table 2. All lesions were chronic total occlusions (CTOs). TASC II D lesions were similarly present in both the subintimal and intraluminal groups (70.4% vs. 68.4%, P=0.716); however, the subintimal group showed a non-significant trend towards a longer lesion length (257.9±87.7 vs. 245.2±70.0 mm, P=0.078) and more frequent presence of combined iliac artery lesions (27.5% vs. 25.1%, P=0.064) than the intraluminal group. Infrapopliteal run-off, concomitantly treated infrapopliteal lesions, and preprocedural ABIs were comparable between the 2 groups.
Table 1.
Baseline Clinical Characteristics of Patients Undergoing Endovascular Treatment of Long Femoropopliteal Artery Occlusions
| |
Intraluminal approach
(n=233) |
Subintimal approach
(n=228) |
P value |
| Age (years) |
69.9±10.1 |
70.2±9.0 |
0.773 |
| Sex, male |
184 (79.0) |
188 (82.5) |
0.406 |
| Hypertension |
167 (71.7) |
170 (74.6) |
0.553 |
| Diabetes mellitus |
111 (47.6) |
114 (50.0) |
0.679 |
| Hypercholesterolemia |
82 (35.2) |
98 (43.0) |
0.106 |
| Chronic kidney disease |
33 (14.2) |
41 (18.0) |
0.322 |
| End-stage renal disease |
16 (6.9) |
21 (9.2) |
0.451 |
| Current smoker |
93 (39.9) |
73 (32.0) |
0.095 |
| Coronary artery disease |
121 (51.9) |
136 (59.6) |
0.115 |
| Stroke |
31 (13.3) |
44 (19.3) |
0.106 |
| Critical limb ischemia |
81 (34.8) |
69 (30.3) |
0.351 |
| Medications at hospital discharge |
| Aspirin |
200 (85.8) |
191 (83.8) |
0.626 |
| Clopidogrel |
196 (84.1) |
184 (80.7) |
0.400 |
| Cilostazol |
109 (46.8) |
93 (40.8) |
0.229 |
| Dual-antiplatelet therapy |
183 (75.0) |
176 (72.4) |
0.588 |
| Triple-antiplatelet therapy |
83 (34.0) |
70 (28.8) |
0.254 |
| Statin |
169 (72.5) |
146 (64.0) |
0.063 |
Dual-antiplatelet therapy: aspirin and clopidogrel. Triple-antiplatelet therapy: aspirin, clopidogrel, and cilostazol.
Table 2.
Lesion and Procedural Data of Patients Undergoing Endovascular Treatment of Long Femoropopliteal Artery Occlusions
| |
Intraluminal approach
(n=244) |
Subintimal approach
(n=243) |
P value |
| TASC |
|
|
0.716 |
| C |
77 (31.6) |
72 (29.6) |
|
| D |
167 (68.4) |
171 (70.4) |
|
| Total occlusion |
244 (100.0) |
243 (100.0) |
0.964 |
| Lesion length, mm |
245.2±70.0 |
257.9±87.7 |
0.078 |
| Stent implantation |
154 (70.3) |
178 (77.1) |
0.129 |
| No. of implanted stents |
1.0±0.9 |
1.2±0.8 |
0.065 |
| Stent diameter, mm |
6.6±0.7 |
6.7±0.7 |
0.047 |
| Stented length, mm |
164.6±88.9 |
172.8±89.9 |
0.407 |
| Stented length/lesion length ratio |
0.5±0.8 |
0.6±0.8 |
0.513 |
| Full-lesion stenting |
53 (24.2) |
62 (26.8) |
0.594 |
| Stent type |
|
|
0.447 |
| SMART |
119 (77.3) |
125 (70.2) |
0.185 |
| Complete SE |
17 (11.0) |
21 (11.8) |
0.965 |
| Zilver |
4 (2.6) |
4 (2.2) |
1.000 |
| Absolute Pro |
10 (6.5) |
18 (14.4) |
0.325 |
| Protégé Everflex |
4 (2.6) |
10 (5.6) |
0.273 |
| Poor distal run-off |
33 (13.5) |
34 (14.0) |
0.986 |
| Combined targets |
| Iliac lesions |
47 (19.3) |
67 (27.5) |
0.064 |
| BTK lesions |
50 (20.5) |
61 (25.1) |
0.269 |
| Ankle-brachial index |
| Preprocedure |
0.5±0.2 |
0.5±0.2 |
0.192 |
| Postprocedure |
0.8±0.2 |
0.8±0.2 |
0.623 |
| Technical success |
219 (89.8) |
231 (95.1) |
0.041 |
| Approach direction |
|
|
0.969 |
| Contralateral |
195 (79.9) |
192 (79.0) |
|
| Ipsilateral |
49 (20.1) |
51 (21.0) |
|
| Bidirectional approach |
49 (20.1) |
10 (4.1) |
<0.001 |
| Use of reentry device |
0 (0) |
30 (12.3) |
<0.001 |
| Directional atherectomy |
5 (2.0) |
3 (1.2) |
0.726 |
| Major complications |
1 (0.4) |
10 (4.1) |
0.014 |
| Bleeding |
0 (0) |
1 (0.4) |
0.998 |
| Access site complications |
0 (0) |
4 (1.6) |
0.131 |
| Distal embolization |
0 (0) |
4 (1.6) |
0.131 |
| Vascular rupture |
1 (0.4) |
1 (0.4) |
>0.999 |
| All complications |
17 (7.0) |
22 (9.1) |
0.496 |
| Bleeding |
12 (4.9) |
6 (2.1) |
0.233 |
| Access site complications |
8 (3.3) |
9 (3.7) |
0.993 |
| Distal embolization |
2 (0.8) |
4 (1.6) |
0.678 |
| Vascular rupture |
4 (1.6) |
7 (2.9) |
0.537 |
BTK, below-the-knee; TASC, Inter-Society Consensus for the Management of Peripheral Arterial Disease.
The technical success rate was higher in the subintimal group (95.1%) than in the intraluminal group (89.8%, P=0.041). An additional distal puncture for a bidirectional approach was performed in 20.1% of the intraluminal group and in 4.1% of the subintimal group (P<0.001). A re-entry device was used in 12.3% of the subintimal group. With adoption of additional retrograde approaches and use of re-entry devices, technical success was improved from 77.6% to 95.1% for the subintimal group and from 73.8% to 89.8% for the intraluminal group. Stent implantation was performed in 77.1% of the subintimal group patients and in 70.3% of the intraluminal group patients, showing no significant difference between groups (P=0.129). The number of stents (1.2±0.8 vs. 1.0±0.9, P=0.065) and the total stented length (172.8±89.9 vs. 164.6±88.9 mm, P=0.407) were comparable between the 2 groups. However, stent diameter was larger in the subintimal group (6.7±0.7 vs. 6.6±0.7, P=0.047). Periprocedural complication rates did not differ significantly between the 2 groups (9.1% vs. 7.0%, P=0.496); however, the incidence of major complication was higher in the subintimal group (4.1%) than in the intraluminal group (0.4%, P=0.014).
Mid-Term Outcomes
The mean follow-up duration was 22.1±20.4 months. The clinical primary patency rates did not differ significantly between groups. The subintimal group, however, showed a trend towards a lower primary patency rate than the intraluminal group (67.5 vs. 73.4% at 12 months and 54.0 vs. 61.3% at 24 months, P=0.086;
Figure 2A). The clinically driven TLR-free survival was 89.5% and 77.6% in the subintimal group and 86.3% and 76.0% in the intraluminal group at 12 and 24 months, respectively, indicating no significant difference between the 2 groups at either time point (P=0.710;
Figure 2B). In the Cox proportional hazard analysis, poor distal run-off (hazard ratio [HR] 2.59, 95% confidence interval [CI] 1.30–5.16, P=0.007), hypercholesterolemia (HR 1.63, 95% CI 1.19–2.23, P=0.002), lesion length per cm (HR 1.002, 95% CI 1.00–1.04, P=0.021), and stent length >150 mm (HR 1.42, 95% CI 1.03–1.99, P=0.034) were identified as independent risk factors for restenosis (Table 3). However, the subintimal approach was not independently associated with restenosis.
Table 3.
Cox Proportional Hazard Regression Model for Restenosis After Endovascular Treatment of Long Femoropopliteal Artery Occlusions
| |
Univariable analysis |
Multivariable analysis |
| HR |
95% CI |
P value |
HR |
95% CI |
P value |
| Subintimal approach |
1.29 |
0.96–1.74 |
0.086 |
1.24 |
0.91–1.69 |
0.167 |
| Age |
1.00 |
0.99–1.02 |
0.871 |
|
|
|
| Female sex |
1.36 |
0.95–1.94 |
0.089 |
1.35 |
0.94–1.93 |
0.109 |
| Hypertension |
0.99 |
0.71–1.39 |
0.976 |
|
|
|
| Diabetes mellitus |
1.06 |
0.79–1.43 |
0.689 |
|
|
|
| Dyslipidemia |
1.61 |
1.20–2.17 |
0.001 |
1.67 |
1.23–2.26 |
0.001 |
| Chronic kidney disease |
0.98 |
0.63–1.54 |
0.945 |
|
|
|
| End-stage renal disease |
1.06 |
0.50–1.78 |
0.853 |
|
|
|
| Current smoker |
1.01 |
0.75–1.37 |
0.927 |
|
|
|
| Coronary artery disease |
0.79 |
0.59–1.06 |
0.111 |
0.72 |
0.53–0.98 |
0.035 |
| Critical limb ischemia |
1.05 |
0.75–1.46 |
0.791 |
|
|
|
| Aspirin |
0.95 |
0.63–1.43 |
0.816 |
|
|
|
| Clopidogrel |
1.16 |
0.76–1.75 |
0.495 |
|
|
|
| Cilostazol |
0.84 |
0.62–1.13 |
0.251 |
|
|
|
| Dual-antiplatelet therapy |
0.99 |
0.71–1.38 |
0.952 |
|
|
|
| Triple-antiplatelet therapy |
0.94 |
0.68–1.29 |
0.697 |
|
|
|
| Statin |
1.08 |
0.78–1.50 |
0.637 |
|
|
|
| Lesion length, mm |
1.00 |
1.00–1.01 |
0.001 |
1.00 |
1.00–1.01 |
0.001 |
| Stent implantation |
1.11 |
0.77–1.61 |
0.578 |
|
|
|
| Stent diameter, mm |
1.10 |
0.88–1.38 |
0.398 |
|
|
|
| Stent length, mm |
1.00 |
0.99–1.00 |
0.183 |
|
|
|
| Stent-to-lesion length ratio >50% |
1.17 |
0.86–1.59 |
0.322 |
|
|
|
| Full-lesion stenting |
0.97 |
0.68–1.40 |
0.889 |
|
|
|
| Combined iliac lesion |
0.82 |
0.86–1.71 |
0.260 |
|
|
|
| Combined BTK lesion |
1.35 |
0.95–1.92 |
0.091 |
0.90 |
0.45–1.79 |
0.761 |
| TASC II D |
1.16 |
0.85–1.60 |
0.347 |
|
|
|
| Poor distal run-off |
1.75 |
1.17–2.62 |
0.006 |
2.04 |
1.06–3.96 |
0.034 |
| Re-entry device |
1.10 |
0.88–1.38 |
0.398 |
|
|
|
BTK, below-the-knee; CI, confidence interval; HR, hazard ratio; TASC, Inter-Society Consensus for the Management of Peripheral Arterial Disease.
Discussion
To summarize, this study demonstrated that the subintimal approach yielded a higher technical success rate, but the patients in this group experienced more major complications than the intraluminal group. The clinical primary patency and clinically driven TLR-free survival did not differ significantly between the subintimal and intraluminal groups. Additionally, poor distal run-off, lesion length, stent length >150 mm, and hypercholesterolemia were identified as independent risk factors for restenosis.
Technical Success and Safety of Subintimal Approach
Since its first application in 1989,3
the subintimal approach has shown improvement in its technical success rate.2,7,12
London et al reported a technical success rate of 81% in occlusions of <10 cm; however, the success rate was only 68% in lesions >20 cm.2
Adoption of an additional retrograde approach through distal pedal or tibial artery puncture and introduction of re-entry devices resulted in a remarkable improvement in the technical success rate of subintimal angioplasty in long CTO lesions.5,7,9,12–14
Yilmaz et al reported an 88% success rate in long superficial femoral artery occlusion (mean length, 20.0 cm) with use of an retrograde approach in 82% of study participants.14
Soga et al used a bidirectional approach in 37% of their subintimal angioplasty group and achieved technical success in 90% of these patients (mean occlusion length, 23.5 cm) even without use of a re-entry device.13
Gandini et al obtained 100% success rate with the Outback Ltd re-entry catheter in TASC II D femoropopliteal artery disease compared with only a 42.3% success rate with a manual re-entry method.7
In our study, we also achieved a high technical success rate (95.1%) in long CTO lesions with use of a combined retrograde approach (4.1%) and re-entry device (12.3%) with the subintimal method.
In this study, the technical success rate of the subintimal approach was higher than that of the intraluminal approach. Our previous single-center study also showed a tendency of higher technical success rates with the subintimal approach (95.1%) than with the intraluminal approach (86.7%, P=0.11) among 121 individuals.15
Soga et al13
reported similar technical success rates for the intraluminal (91%) and subintimal (90%) approaches based on intention-to-treat analysis; however, in their study, 25% of the intraluminal approach cases crossed over to become subintimal approach cases after difficulty with intraluminal angioplasty. Thus, the subintimal approach appears to achieve a higher technical success rate than intraluminal angioplasty.
On the other hand, the major complication rate was higher for the subintimal approach group than the intraluminal approach group in that study.13
Most of the major complications in the subintimal group were access site complications and distal embolizations. In our opinion, the access site complications may not be directly related to the subintimal approach. Inclusion of thrombotic lesions may have been the reason for increased distal embolization requiring surgical interventions in the subintimal group. Previous studies reported no significant difference in complications rates between the subintimal and intraluminal groups.12,16
As the major complication rates of subintimal angioplasty in the previous studies varied from 0% to 13%,7,12,15,16
the periprocedural complication rates (4.1% for major complicates and 9.1% for all complications) observed in this study appear to be still rather low.
Patency After Subintimal Angioplasty
The 1-year patency rates for the subintimal approach for long CTO lesion of ≥20 cm in early studies ranged from 22% to 56%.2,13,17
With the introduction of self-expanding stents, however, the patency rate of the subintimal approach improved remarkably.9,12,15,17–19
In a meta-analysis of 37 studies, the 12-month primary patency rate was found to be 47.9% for the subintimal approach without implantation of stents, 61.6% for the subintimal approach with provisional stenting, and 69.2% for the subintimal approach with primary stenting.17
In our study, adoption of different stenting strategies depending on the operator resulted in a primary patency rate in the subintimal group of 67.5% at 1 year and 54.0% at 2 years, consistent with previous studies. These primary patency rates were also similar to those observed for the Japanese registry, as reported by Soga et al;13
however, in contrast to the Japanese registry results, spot stenting rather than long stenting was preferentially performed in our study. Long stenting or ‘full-metal jacket’ stenting has been reported to be associated with increased risk of restenosis in previous studies,5,19
but because of the unavailability of detailed procedural data from the Japanese registry study, it is difficult to compare the data from the 2 registries.
To date, no randomized controlled trial directly comparing subintimal angioplasty vs. intraluminal angioplasty for femoropopliteal artery disease has been published; however, several retrospective studies demonstrated no significant difference between the 2 wire-crossing techniques in terms of primary patency or TLR-free survival.12,15,20
In the present study, the subintimal approach showed a trend towards lower primary patency compared with the intraluminal approach. However, the subintimal approach was not associated with restenosis in the Cox proportional hazard multivariate analysis model after adjustment for confounding factors. Thus, the wire-crossing technique (i.e., subintimal or intraluminal) does not seem to have an effect on the mid-term patency. In agreement with previous studies, poor distal run-off, lesion length, stent length >150 mm, and hypercholesterolemia were identified as independent risk factors for restenosis in this study.5,19,21,22,23
Study Limitations
First, this was a retrospective study with the inherent limitations involved in retrospective studies involving electronic medical records. Second, subintimal or intraluminal passage of the wires was not confirmed by intravascular ultrasound during the procedure. Thus, we used the term “subintimal approach” instead of “subintimal angioplasty.” Third, differences in procedural skills and strategies of the operators could not be considered because of the limited study population. Fourth, during the 10 years that procedures were performed, there might have been changes in technique of procedures and choice of stents. However, the present study did not include cases of treatment with interwoven nitinol stents or drug-eluting technologies that might have affected the primary patency. In the choice of stents, there was no significant difference between the intraluminal and subintimal groups. Fifth, there was no information on the severity of calcification in the target lesion. Heavily calcified lesions are often challenging for endovascular procedures and affect the treatment strategy. However, currently, there is no established consensus on how to define the severity of calcification.
Conclusions
In complex femoropopliteal occlusive lesions, the subintimal approach achieved a higher technical success rates as well as similar mid-term primary patency and TLR-free survival rates compared with the intraluminal approach.
Acknowledgments
This study was supported by grants from the Korean Vascular Intervention Society; the Mid-Career Researcher Program through an NRF grant funded by the MEST, Republic of Korea (2015R1A2A2A01002731); and the Cardiovascular Research Center, Seoul, Korea.
Supplementary Files
Supplementary File 1
Appendix S1. K-VIS Investigators
Please find supplementary file(s);
http://dx.doi.org/10.1253/circj.CJ-17-1464
References
- 1.
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.
- 2.
London NJ, Srinivasan R, Naylor AR, Hartshorne T, Ratliff DA, Bell PR, et al. Subintimal angioplasty of femoropopliteal artery occlusions: The long-term results. Eur J Vasc Surg 1994; 8: 148–155.
- 3.
Bolia A, Brennan J, Bell PR. Recanalisation of femoro-popliteal occlusions: Improving success rate by subintimal recanalisation. Clin Radiol 1989; 40: 325.
- 4.
Laxdal E, Jenssen GL, Pedersen G, Aune S. Subintimal angioplasty as a treatment of femoropopliteal artery occlusions. Eur J Vasc Endovasc Surg 2003; 25: 578–582.
- 5.
Siablis D, Diamantopoulos A, Katsanos K, Spiliopoulos S, Kagadis GC, Papadoulas S, et al. Subintimal angioplasty of long chronic total femoropopliteal occlusions: Long-term outcomes, predictors of angiographic restenosis, and role of stenting. Cardiovasc Intervent Radiol 2012; 35: 483–490.
- 6.
Scott EC, Biuckians A, Light RE, Scibelli CD, Milner TP, Meier GH 3rd, et al. Subintimal angioplasty for the treatment of claudication and critical limb ischemia: 3-year results. J Vasc Surg 2007; 46: 959–964.
- 7.
Gandini R, Fabiano S, Spano S, Volpi T, Morosetti D, Chiaravalloti A, et al. Randomized control study of the outback LTD reentry catheter versus manual reentry for the treatment of chronic total occlusions in the superficial femoral artery. Catheter Cardiovasc Interv 2013; 82: 485–492.
- 8.
Duda SH, Bosiers M, Lammer J, Scheinert D, Zeller T, Oliva V, et al. Drug-eluting and bare nitinol stents for the treatment of atherosclerotic lesions in the superficial femoral artery: Long-term results from the SIROCCO trial. J Endovasc Ther 2006; 13: 701–710.
- 9.
Palena LM, Diaz-Sandoval LJ, Sultato E, Brigato C, Candeo A, Brocco E, et al. Feasibility and 1-Year outcomes of subintimal revascularization with supera(R) stenting of long femoropopliteal occlusions in critical limb ischemia: The “Supersub” Study. Catheter Cardiovasc Interv 2017; 89: 910–920.
- 10.
Chang Z, Zheng J, Liu Z. Subintimal angioplasty for lower limb arterial chronic total occlusions. Cochrane Database Syst Rev 2016; 11: CD009418.
- 11.
Ko YG, Ahn CM, Min PK, Lee JH, Yoon CH, Yu CW, et al. Baseline characteristics of a retrospective patient cohort in the Korean Vascular Intervention Society Endovascular Therapy in Lower Limb Artery Diseases (K-VIS ELLA) Registry. Korean Circ J 2017; 47: 469–476.
- 12.
Jongsma H, Bekken JA, de Vries JP, Verhagen HJ, Fioole B. Drug-eluting balloon angioplasty versus uncoated balloon angioplasty in patients with femoropopliteal arterial occlusive disease. J Vasc Surg 2016; 64: 1503–1514.
- 13.
Soga Y, Iida O, Suzuki K, Hirano K, Kawasaki D, Shintani Y, et al. Initial and 3-year results after subintimal versus intraluminal approach for long femoropopliteal occlusion treated with a self-expandable nitinol stent. J Vasc Surg 2013; 58: 1547–1555.
- 14.
Yilmaz S, Sindel T, Yegin A, Luleci E. Subintimal angioplasty of long superficial femoral artery occlusions. J Vasc Interv Radiol 2003; 14: 997–1010.
- 15.
Ko YG, Kim JS, Choi DH, Jang Y, Shim WH. Improved technical success and midterm patency with subintimal angioplasty compared to intraluminal angioplasty in long femoropopliteal occlusions. J Endovasc Ther 2007; 14: 374–381.
- 16.
Gabrielli R, Rosati MS, Vitale S, Baciarello G, Siani A, Chiappa R, et al. Randomized controlled trial of remote endarterectomy versus endovascular intervention for TransAtlantic Inter-Society Consensus II D femoropopliteal lesions. J Vasc Surg 2012; 56: 1598–1605.
- 17.
Treiman GS, Treiman R, Whiting J. Results of percutaneous subintimal angioplasty using routine stenting. J Vasc Surg 2006; 43: 513–519.
- 18.
Bown MJ, Bolia A, Sutton AJ. Subintimal angioplasty: Meta-analytical evidence of clinical utility. Eur J Vasc Endovasc Surg 2009; 38: 323–337.
- 19.
Hong SJ, Ko YG, Kim JS, Hong MK, Jang Y, Choi D. Midterm outcomes of subintimal angioplasty supported by primary proximal stenting for chronic total occlusion of the superficial femoral artery. J Endovasc Ther 2013; 20: 782–791.
- 20.
Hong SJ, Ko YG, Shin DH, Kim JS, Kim BK, Choi D, et al. Outcomes of spot stenting versus long stenting after intentional subintimal approach for long chronic total occlusions of the femoropopliteal artery. JACC Cardiovasc Interv 2015; 8: 472–480.
- 21.
Babaev A, Hari P, Gokhale R, Zavlunova S. A single center retrospective analysis of patency rates of intraluminal versus subintimal endovascular revascularization of long femoropopliteal occlusions. Cardiovasc Revasc Med 2017; 18: 399–404.
- 22.
Iida O, Takahara M, Soga Y, Suzuki K, Hirano K, Kawasaki D, et al. Shared and differential factors influencing restenosis following endovascular therapy between TASC (Trans-Atlantic Inter-Society Consensus) II class A to C and D lesions in the femoropopliteal artery. JACC Cardiovasc Interv 2014; 7: 792–798.
- 23.
Baril DT, Marone LK, Kim J, Go MR, Chaer RA, Rhee RY. Outcomes of endovascular interventions for TASC II B and C femoropopliteal lesions. J Vasc Surg 2008; 48: 627–633.
