Comparison Of Primary Long Stenting Versus Primary Short Stenting For Long Femoropopliteal Artery Disease (PARADE) Young-Guk Ko, M.D. Severance Cardiovascular Hospital, Yonsei University Health System, Seoul, Korea
Disclosure Speaker name:... I have the following potential conflicts of interest to report: Consulting Employment in industry Stockholder of a healthcare company X Owner of a healthcare company Other(s): Research fund from Cordis for this study I do not have any potential conflict of interest
Background Primary stenting is superior to provisional stenting for immediate length FP lesions. However, optimal stenting strategy for long lesions is still unknown. Longer stent length is generally associated with increased risk of in-stent restenosis and stentfracture in FP artery.
M/85, SFA CTO treated by subintimal angioplasty & spot stenting
Spot Stenting vs. Long Stenting after Subintimal Approach in FP Artery CTOs 77% 47% J Am Coll Cardiol Intv 2015;8:472
Study Design A investigator-initiated multicenter randomized trial comparing primary long stenting versus primary short stenting (1:1) for femoropopliteal artery lesions longer than 8 cm. (www.clinicaltrials.gov NCT 01359423) Study population: 110 patients planned for each group Participating centers: 11 Korean endovascular centers PI: Donghoon Choi, MD, PhD Severance Cardiovascular Hospital, Seoul, Korea Device: SMART stents (Cordis)
Inclusion Criteria Femoropopliteal artery lesions with stenosis of >50% and length >80 mm Symptoms of intermittent claudication or critical limb ischemia (Rutherford 2~5) Presence of at least one patent infrapopliteal run-off vessel.
Exclusion Criteria Age over 85 years, Acute limb ischemia, Severe CLI (Rutherford 6), Previous bypass surgery or stenting of the target superficial femoral artery, Untreated inflow disease (iliac artery disease) Known intolerance to antiplatelet drugs or contrast agents, Severe hepatic disease, renal failure with Cr >2.0 mg/dl, CHF or LVEF <40%, Life expectancy < 1 year.
Predilation Endovascular Procedure: Long stenting group The stents are implanted to extend 10 mm proximally and distally from the margins of the target lesion with luminal narrowing of >50%. When multiple stents are required, the margins of the stents overlapped 10 mm. Dilation after stenting is performed strictly within the stented segment, with up to 10 percent oversizing of the postdilation balloon.
Endovascular Procedure: Short stenting group Predilation for at least 2 min. If suboptimal result (defined as a residual stenosis >30%, the presence of a flow-limiting dissection, a transstenotic peak-to-peak systolic PG >15 mmhg after injection of vasodilators) => 2 nd balloon dilation If persistently suboptimal => spot stenting If optimal after 1 st or 2 nd balloon dilation => Stenting at the most narrowed lesion or at the site of dissection
Primary Endpoints The primary patency rate in the treated segment 12 months after intervention, as determined by imaging studies (CT angiography, Duplex US or catheterbased angiography) according to the stenting strategy
Study flow Enrollment: November 2011~ August 2015
Baseline Clinical Characteristics Short stenting Long stenting P-value (n=59) (n=66) Age, years 70.0±7.7 70.3±7.9 0.819 Male 53 (89.8%) 54 (81.8%) 0.203 Body mass index, kg/m 2 23.1±3.1 22.3±3.0 0.240 Hypertension 47 (79.7%) 48 (73.8%) 0.445 Diabetes mellitus 30 (50.8%) 32 (49.2%) 0.857 Current smoker 34 (57.6%) 24 (36.4%) 0.017 Hypercholesterolemia 24 (40.7%) 19 (29.2%) 0.181 Chronic kidney disease 5 (8.5%) 3 (4.6%) 0.476 Coronary artery disease 21 (35.6%) 20 (30.8%) 0.569 Previous stroke 10 (16.9%) 15 (23.1%) 0.396 Critical limb ischemia 11 (18.6%) 20 (30.3%) 0.132 ABI 0.53±0.18 0.58±0.19 0.140 Discharge medication Aspirin 56 (94.9%) 58 (87.9%) 0.285 Clopidogrel 48 (81.4%) 52 (89.4%) 0.893 Cilostazol 37 (62.7%) 43 (65.2%) 0.922
Lesion & Procedural Data Short stenting Long stenting P-value (n=59) (n=66) Lesion length (cm) 24.5 ± 9.5 23.8 ± 8.0 0.675 Lesion length >15 cm 47 (79.7%) 54 (81.8%) 0.760 Total occlusion 53 (89.8%) 58 (87.9%) 0.730 Lesion type (TASC II) 0.678 B 9 (15.3%) 9 (13.6%) C 15 (25.4%) 13 (19.7%) D 35 (59.3%) 44 (66.7%) Popliteal artery involvement 10 (17.2%) 10 (15.9%) 0.840 Distal run-off vessels 1 19 (32.2%) 14 (21.2%) 0.164 Subintimal approach 34 (57.6%) 41 (54.1%) 0.465 Mean number of stents 1.2 ± 0.4 2.0 ±0.6 <.001 Stented length (cm) 11.6±4.5 24.2±8.1 <.001 Popliteal artery stenting 0 (0%) 6 (9.5%).028 P 1 segment 0 6 P 2 or P 3 segment 0 0 Treated combined lesions
Immediate Results Short stenting Long stenting (n=59) (n=66) Crossed to long stenting 3 (5.1%) - P-value Technical success 59 (100%) 66 (100%) Complications 2 (3.4%) 3 (4.5%) 1.000 a Distal embolization 2 (3.4%) 0 (0%) 0.221 a Vascular perforation 0 (0%) 1 (1.5%) 1.000 Access site hematoma 0 (0%) 2 (3.0%) 0.500 Major complications 0 (0%) 0 (0%) -
Primary Patency 86.1% 87.4% 72.0% 72.5% 72.7% 60.3% 72.3% 60.4%
TLR-free Survival 94.2% 81.6% 93.9% 80.6% 82.5% 72.7% 83.5% 74.1% Short stenting Long stenting
Stent Fractures Short stenting (n=25) Long stenting (n=24) P-value Stent fractures 2 (8.0%) 5 (20.8%) 0.247 Type 1 1 2 Type 2 1 1 Type 3 0 2 Type 4/5 0 0 Restenosis 2 (8.0%) 2 (8.3%) 1.000
Risk Factors of Restenosis Univariate analysis Multivariate analysis HR (95% CI) P-value HR (95% CI) P-value Age 0.96 (0.92-1.00) 0.077 0.94 (0.90-1.00) 0.035 Body mass index 0.90 (0.81-1.01) 0.072 0.93 (0.82-1.04) 0.198 Diabetes mellitus 1.13 (0.59-2.18) 0.716 Current smoker 1.20 (0.62-2.31) 0.584 Critical limb ischemia 1.31 (0.46-3.79) 0.613 Pre-procedural ABI 0.52 (0.09-3.17) 0.478 Use of cilostazol >6 mo 0.56 (0.41-1.79) 0.090 0.51 (0.23-1.10) 0.085 Lesion length 1.00 (1.00-1.00) 0.718 Lesion length >150 mm 2.14 (0.75-6.08) 0.156 Total occlusion 0.95 (0.34-2.72) 0.930 TASC II D lesion 1.31 (0.66-2.63) 0.443 Popliteal artery stenting 0.58 (0.13-2.59) 0.479 Subintimal angioplasty 0.91 (0.46-1.80) 0.781 Long stenting 1.56 (0.73-3.34) 0.249 Stented length (per mm) 1.00 (1.00-1.01) 0.032 1.01 (1.00-1.01) 0.011
Summary Despite less frequent use of stents and shorter stent length, technical success was achieved in all patients in the short stenting group. Primary patency and TLR-free survival did not differ significantly between the short stenting and long stenting groups. However, the short stenting group trended toward higher primary patency and TLR-free survival at 12 months. We found that stented length was an independent predictors of restenosis along with younger age. However, lesion length was not associated with increased restenosis rate.
Limitations This study was underpowered due to insufficient enrollment of study subjects. We did not routinely perform intravascular ultrasound during the procedure to verify the subintimal passage of the wires. The definition of short stenting was arbitrary. We did not set any limit to stent length or stent-to-lesion length ratio.
Conclusion Not lesion length, but stented length was associated with increased risk of restenosis in long FP artery disease. Therefore, spot stenting appears to be more preferable.