Determinants of patency after percutaneous angioplasty and atherectomy of occluded superficial femoral arteries

Prognostic Factors for Restenosis of Superficial Femoral Artery after Endovascular Treatment

High incidence of superficial femoral artery (SFA) restenosis after percutaneous transluminal angioplasty (PTA) poses a persistent challenge in peripheral arterial disease (PAD) treatment. We studied how the patients' and lesions' characteristics, thrombin generation, overall haemostatic potential (OHP), and single nucleotide polymorphisms (SNPs) of the NR4A2 and PECAM1 genes affected the likelihood of restenosis. In total, 206 consecutive PAD patients with limiting intermittent claudication due to SFA stenosis who were treated with balloon angioplasty with bailout stenting when necessary were included. Patients' clinical status and patency of the treated arterial segment on ultrasound examination were assessed 1, 6, and 12 months after the procedure. Restenosis occurred in 45% of patients, with less than 20% of all patients experiencing symptoms. In the multivariate analysis, predictors of restenosis proved to be poor infrapopliteal runoff, higher lesion complexity, absence of treated arterial hypertension, delayed lag phase in thrombin generation, and higher contribution of plasma extracellular vesicles to thrombin concentration. Poor infrapopliteal runoff increased the risk of restenosis in the first 6 months, but not later. The negative effect of poor infrapopliteal runoff on SFA patency opens questions about the potential benefits of simultaneous revascularisation of below-knee arteries along with SFA revascularisation.

Endovascular Intervention for the Treatment of Trans-Atlantic Inter-Society Consensus (TASC) D Femoropopliteal Lesions: A Systematic Review and Meta-Analysis

PURPOSE

Advancements in the endovascular treatment of femoropopliteal atherosclerotic lesions have led to treatment of more complex lesions, particularly long lesions. The aim of this study was to determine the meta-analytic primary patency and need for re-intervention among patients treated for very long lesions (>200 mm) at the femoropopliteal segment and to identify potential risk factors for loss of patency.

METHODS

This study was performed according to the PRISMA guidelines. A random effects model meta-analysis was conducted, and the I-square was used to assess heterogeneity.

RESULTS

Fifty-one studies comprised of 3029 patients were included. The mean lesion length was 269 mm. The primary patency rate at 30 days, 6 m, 1-, 2- and 5-years of follow-up was 98%, 76%, 62%, 55%, and 39% respectively. The incidence of TLR was 16% at one year and 32% at two years. The secondary patency rate at 1, 2, 3 and 5 years was 85%, 71%, 64%, and 64% respectively. Heparin bonded ePTFE covered stents (69%) and paclitaxel eluting stents (73%) demonstrated higher 1-year primary patency rates than self-expanding nitinol stents (55%) or uncoated percutaneous transluminal angioplasty (PTA) with provisional stenting (54%). Lesions treated with a heparin bonded ePTFE covered stent had statistically significant higher odds of remaining patent at 1-year of follow-up (OR: 2.74; 95%CI: 1.63-4.61; p < 0.001) than lesions treated with BMS or PTA. Patients with long femoropopliteal lesions causing critical limb ischemia (CLI) developed restenosis or occlusion more often than patients treated for claudication (HR: 1.63; 95%CI: 1.06-2.49; p = 0.026) during an average follow-up of 26 months.

CONCLUSION

Primary stenting of femoropopliteal TASC D lesions using drug eluting stents or covered stents results in sustained patency over time. PTA or uncoated nitinol stents demonstrated lower patency rates. However, additional comparative studies are needed to determine the efficacy of newer technologies for the treatment of complex femoropopliteal lesions and provide evidence for the most optimal treatment approach.

The association of statin therapy with the primary patency of femoral and popliteal artery stents

OBJECTIVE

It has long been known that hydroxymethylglutaryl-coenzyme A reductase inhibitors (statins) broadly reduce cardiovascular events in patients with peripheral vascular disease. It was the goal of this study to determine whether there is an association between statin therapy and primary patency after stenting of superficial femoral and popliteal arteries.

METHODS

The records of all patients undergoing primary nitinol stenting of the femoral and popliteal arteries at a single institution and by a single surgeon during a 10-year period were reviewed. Demographic characteristics of the patients and risk factors were identified. TransAtlantic Inter-Society Consensus (TASC II) classifications were determined for all stented lesions. Analysis was performed to determine whether the use of statins at the time of stent placement was associated with a change in rates of primary patency. Loss of primary patency was said to have occurred when an intrastent occlusion or a ≥70% stenosis was identified by arterial duplex ultrasound or angiography. Kaplan-Meier survival curves were plotted, and differences between groups were tested by log-rank method.

RESULTS

Between 2004 and 2014, primary femoral or popliteal stenting was performed on 308 limbs in 250 patients. At the time of intervention, 52.4% of these patients were being treated with statin therapy; 137 interventions were done for claudication and 113 for critical limb ischemia. Of the lesions treated, 165 were TASC A or B and 85 were TASC C or D. Primary patency rates for all stented lesions were 75%, 54%, and 35% at 12, 24, and 36 months. The patency rates at 12, 24, and 36 months, respectively, were 80%, 55%, and 40% for those taking statins and 68%, 49%, and 28% for those not taking statins (P = .178). Statin therapy demonstrated a trend toward an association with improved primary patency rates in TASC A/B lesions but had no association in TASC C/D lesions (TASC A/B, P = .056; TASC C/D, P = .537). Statin compliance was found to be 87% at a mean follow-up of 24.1 months.

CONCLUSIONS

Although the use of statins has been shown to reduce cardiovascular morbidity and mortality in patients with peripheral vascular disease, overall there is not an association of these drugs with improved primary patency after primary stenting of femoral and popliteal artery lesions. However, when limbs are stratified for severity, less severe (TASC A/B) lesions demonstrated a trend toward a significant association between statin use and improved primary patency. This finding was not seen in more severe (TASC C/D) disease.

Primary stenting of the superficial femoral and popliteal artery

OBJECTIVES

Over the last decade, the number of endovascular procedures performed on the superficial femoral (SFA) and popliteal arteries (PA) has significantly increased. There is no consensus on the optimal form of intervention used in this arterial segment. While some have advocated balloon angioplasty alone, others have championed either selective or primary stenting of these lesions. It is the purpose of this study to determine the efficacy and durability of primary stenting of the superficial femoral and popliteal artery.

METHODS

All patients undergoing peripheral angioplasty by a single vascular surgeon were prospectively enrolled in an Institutional Review Board-approved, primary-stenting protocol. During a 44-month period, all patients undergoing percutaneous transluminal angioplasty of the SFA or PA also received primary arterial stenting with bare, self-expanding nitinol stents. Patient demographics and risk factors were identified. TransAtlantic InterSociety Consensus (TASC) classifications were determined for all lesions. Loss of primary patency was said to have occurred when an occlusion or a 50% or greater stenosis in any treated arterial segment was diagnosed by arterial duplex or angiography. Only time to loss of primary patency was recorded. Kaplan-Meier survival curves were plotted and differences between groups tested by log rank method.

RESULTS

Between January 16, 2004 and August 13, 2007, 201 angioplasties with primary stenting were performed on 161 patients. One hundred twenty-three stents were placed for claudication, and 78 for critical limb ischemia. Forty-six segments treated were TASC A, 82 were TASC B, 38 were TASC C, and 35 were TASC D. Patient follow-up ranged from three to 1329 days (mean: 426 days). Primary patency rates for TASC A and B lesions were 79%, 67%, and 57% at 12, 24, and 36 months. For TASC C and D lesions, primary patency rates were 52.7%, 36%, and 19% at the same time intervals. Primary patency rates for TASC A and B lesions were significantly higher than for C and D lesions (P < .001). The limb salvage rate was 88.5% in patients with critical limb ischemia. Distal runoff did not influence patency (P = .827).

CONCLUSIONS

Primary stenting of the SFA and PA provides durable results in patients with TASC A and B lesions and may be an effective treatment strategy. This approach is significantly less effective when used in treating those with TASC C and D disease. Based on the results in this series, the use of primary stenting does not extend the anatomic limits of the current treatment recommendations for catheter-based intervention in patients with infrainguinal occlusive disease.

Transluminal Stenting for Femoropopliteal Occlusive Disease: Analysis of Restenosis by Serial Arteriography

Our objective was to evaluate restenosis after stenting of femoropopliteal occlusions and the impact of percutaneous transluminal angioplasty (PTA) on recurrent stenosis. We used a retrospective analysis of contrast angiograms obtained during follow-up of stented limbs. Subjects included 27 claudicants (34 limbs) who had complete superficial femoral artery occlusion treated with PTA and Wallstents at the Veterans Adminstration Medical Center. During follow-up, 31 PTAs, three thrombolytic treatments, and one additional stenting were performed. Outcome was measured by contrast angiography. Primary patency at 1 and 3 years was 38% and 8% after stenting, and secondary patency (PTA required at least once in 21/34 limbs) was 89% and 55%, respectively. PTA performed during follow-up reduced within-stent restenosis on average from 48.3 +/- 13.6% to 22.8 +/- 18.0%. Recurrent stenosis after PTA measured 14.9 +/- 10.9 months later was 46.8 +/- 16.7%, showing little permanent impact of PTA on stenosis. Severe within-stent stenosis develops commonly after initial stenting of complete femoropopliteal occlusions. Supplemental PTA performed during follow-up provides immediate improvement in lumen diameter, but severe restenosis is still likely to recur.

Complex endovascular treatment for critical limb ischemia in poor surgical candidates: a pilot study

PURPOSE

To evaluate the effectiveness of complex endovascular treatment for limb salvage in patients with critical limb ischemia.

METHODS

In a prospective study, 23 patients (13 men; mean age 70 +/- 11 years, range 44-87) with ischemic ulceration or gangrene of 25 lower limbs were enrolled at 4 sites to evaluate treatment with excimer laser recanalization followed by balloon angioplasty with optional stenting in the superficial femoral, popliteal, and/or tibial arteries.

RESULTS

Multiple lesions (mean 3.1, range 1-8) were treated in most cases. Reduction of stenosis/occlusion to <50% was achieved in 22 (88%) limbs. Individual cases of vessel perforation, inability to cross the lesion, and excessive residual stenosis accounted for the 3 failures. Over a 6-month period, 4 patients died of cardiac comorbidity and 1 was lost to follow-up. Adverse events included 4 minor and 2 below-knee amputations, 4 secondary angioplasties, and 4 femorodistal bypasses. The mean wound area reduction was 70% at 3 months, increasing to 89% at 6 months. According to life table analysis, the limb salvage rate was 90% with bypass and 69% without in the successfully treated patients (corresponding intention-to-treat rates were 79% and 61%).

CONCLUSIONS

Complex endovascular treatment combining laser debulking and angioplasty/stenting offers an alternative for patients with critical limb ischemia who lack good surgical options.

Failure of prolonged dilation to improve long-term patency of femoropopliteal artery angioplasty: results of a prospective trial

PURPOSE

To determine long-term patency of femoropopliteal artery percutaneous transluminal angioplasty (PTA) in a prospective trial during which prolonged balloon inflation was used for optimization of initial results.

MATERIALS AND METHODS

Femoropopliteal PTA was performed in 112 limbs of 97 patients. The mean total length of the treated segments was 7.2 cm (95% CI: 5.99-8.46; median: 5.5 cm). In cases of unsatisfactory primary results after standard dilation for 1-3 minutes, the procedure was continued with prolonged dilation (93 limbs; mean balloon inflation time: 31 min; 95% CI: 24.2-37.7; median: 15 min) with use of the same balloon catheter (77 limbs) or a perfusion balloon catheter (35 limbs). Thirty-four proximal infrapopliteal artery stenoses were treated to improve peripheral runoff and 12 short stents were placed because of flow-limiting dissections.

RESULTS

Primary hemodynamic success established by Doppler ultrasound (US) criteria was achieved in 92.9% (104 of 112) of the limbs. Three major complications were encountered; none were related to prolonged balloon inflation. The primary patency rate according to Kaplan-Meier analysis was 42% (+/-5% SE) at 1 year and 39% (+/-5%) at 2 and 3 years. The corresponding secondary patency rates were 51% (+/-5%) and 47% (+/-5%). Large numbers of diseased vessels in the treated limb (four to 10 instead of one to three), eccentric lesions (as opposed to concentric morphology), and additional treated segments (instead of only femoropopliteal lesions) were associated with poorer long-term patency. The duration of balloon dilation was not a determinant of long-term patency.

CONCLUSION

Although prolonged dilation is safe and feasible in femoropopliteal artery PTA, its routine use is not warranted because it does not result in superior long-term patency rates.

Predictors of long-term patency after femoropopliteal angioplasty: results from the STAR registry

PURPOSE

To identify variables predictive of long-term patency after femoropopliteal angioplasty.

MATERIALS AND METHODS

The primary patency of 219 limbs in 205 patients from a multicenter registry who underwent femoropopliteal angioplasty between January 1, 1992, and December 31, 1994, was prospectively monitored with a combination of angiography, noninvasive hemodynamic testing, and clinical outcome. Patient demographic, angiographic, and hemodynamic variables were examined alone and in combination to determine effect on long-term primary patency. Each limb was graded as Category 1-4 according to the American Heart Association (AHA) criteria for arterial lesions, and differences in outcome for each category were examined. Primary patency and intergroup analysis were determined with use of the Kaplan-Meier method and log-rank test, respectively. Cox proportional hazards models were used to calculate relative risks for predictive variables.

RESULTS

Primary patency rates for all limbs (on an intent-to-treat basis) at 12, 24, and 36 months were 87% +/- 3%, 80% +/- 3%, and 69% +/- 5%, respectively. Primary patency at 48 and 60 months was 55% +/- 7%. Poor tibial runoff (single tibial vessel with 50%-99% stenosis or occlusion) was most predictive of occlusion (relative risk 8.5, P <.0001). The presence of diabetes or renal failure was associated with lower long-term patency (relative risk 5.5 and 4.0, P <.0001 and.0002, respectively). Long-term patency was higher with AHA Category 1 lesions (P =.006), and no significant difference in patency was observed between Category 2 and 3 lesions (P =.65). A multivariate Cox proportional hazards model showed only the stratified runoff score and the presence of diabetes to be significant determinants of long-term patency.

CONCLUSION

Poor tibial runoff is most predictive of lower long-term patency rates. Diabetes is also independently associated with lower long-term patency rates. The criteria that distinguish Category 2 and 3 lesions do not predict differences in long-term patency, nor do they serve to identify lesions best treated with surgical bypass. This suggests that indications for femoral angioplasty can be extended to include longer and more complex Category 3 lesions.

Angioplasty and stent placement in chronic occlusion of the superficial femoral artery: technique and results

PURPOSE

To improve the patency rate for angioplasty in chronic occlusion of the superficial femoral artery by deploying stents after angioplasty.

MATERIALS AND METHODS

Angioplasty and stent placement were performed in 61 arteries in 48 male patients. The mean occlusion length was 13.5 cm and the mean stent length was 30 cm. Patency rates were analyzed at 6 months and at 1, 2, 3, and 4 years. The predictors of restenosis were analyzed by univariate and multiple logistic regression.

RESULTS

Patency rates were 87% at 6 months, consisting of 74% primary, 6% primary assisted, and 7% secondary; 79% at 1 year, consisting of 47% primary, 19% primary assisted, and 13% secondary; 72% at 2 years, consisting of 36% primary, 26% primary assisted, and 10% secondary; 70% at 3 years, consisting of 26% primary, 22% primary assisted, and 22% secondary; and 63% at 4 years, consisting of 25% primary, 0% primary assisted, and 38% secondary. There was a 15% morbidity rate and one mortality as a result of retroperitoneal bleeding. Better patency rates were noted at all time intervals in diabetic limbs, 7-mm-diameter versus 10-mm-diameter stents, shorter obstructions and shorter stents, nonsmokers, in limbs in which urokinase was not necessary after stent deployment, and in limbs with an International Society of Cardiovascular Surgery (ISCVS) classification under 3. Patency rates were not affected by age, race, number of trifurcation vessels patent, experience in performing the procedures, and procedures requiring less time. By multivariate logistic analysis, the independent predictors of patency at 6 months were postprocedure ankle/brachial index (ABI) and shorter stent length; at 1 year, preprocedure ABI, shorter stent length, and the presence of diabetes; at 2 years, preprocedure ABI and the presence of diabetes; and at 3 years, the preprocedure ABI.

CONCLUSIONS

The techniques used to reestablish antegrade flow in these superficial femoral arteries yielded a high success rate. In addition, the use of angioplasty with stents may improve patency rates over angioplasty without stents.

The changes seen in balloon-injured porcine femoral arteries following sympathectomy

On the basis that vasoconstriction may contribute to restenosis following angioplasty, the influence of lumbar sympathectomy on the morphometry of femoral arteries after balloon injury was examined in a pig model. Twenty-six juvenile pigs underwent balloon de-endothelialization of the right femoral artery followed by an open bilateral lumbar sympathectomy (n = 14) or a sham sympathectomy (n = 12). Four weeks later flow was measured in femoral arteries. Animals were then killed and the femoral arteries were perfusion-fixed and harvested. Sympathectomy resulted in a significant (P = 0.04) increase in flow in both the injured (right) and uninjured (left) femoral arteries. Sympathectomy did not inhibit intimal thickening following balloon injury: median (interquartile range) intimal area was 0.4 mm2 (0.3-0.9) in the sympathectomy group versus 0.5 mm2 (0.4-0.9) in the sham group. Sympathectomy did, however, result in a significant (P = 0.02) increase in the lumen area: 1.1 mm2 (0.8-1.8) versus 0.7 mm2 (0.6-0.9). Sympathectomy may reduce vasospasm following angioplasty with the potential for clinical benefit.

Minimally invasive superficial femoral artery endarterectomy: early experience with a modified technique

OBJECTIVES

To describe our experience of a modified technique for carrying out remote endarterectomy for superficial femoral artery occlusive disease.

METHODS

A 4-French arterial dilator is inserted using a Smart needle into the popliteal artery below the occlusion. A remote endarterectomy is carried out through an arteriotomy in the proximal superficial femoral artery. The atheroma is cut distal to the lower extent of disease using a Moll ring cutter. The lower flap of atheroma is secured with an intraluminal stent inserted from the arteriotomy in the superficial femoral artery. The arteriotomy is extended into the common femoral artery and closed with a vein patch.

RESULTS

The procedure was completed in 21 of 26 limbs. In 18 cases the superficial femoral artery remained patent at 30 days. Of the 21 cases all but four stayed in hospital for one night. A successful femoropopliteal bypass was carried out in the five patients in whom the procedure was not completed.

CONCLUSION

Insertion of the dilator into the popliteal artery distal to the occlusion before carrying out the remote endarterectomy has two advantages. Firstly, the stent insertion is carried out in the correct plane and prevents dissection of the distal cut atheroma when attempting to pass the guidewire from above. Secondly, the procedure can be carried out under simple image intensification without sophisticated radiological equipment. The early results are encouraging and further evaluation of the technique is justifiable.

The impact of atherosclerotic arterial remodeling on percentage of luminal stenosis varies widely within the arterial system. A postmortem study

Luminal stenosis can be based on large atherosclerotic plaques in compensatory enlarged segments or on relatively little plaques in shrunken segments. In the present study, the contribution of plaque formation and remodeling to luminal narrowing was compared among six types of arteries prone to symptomatic atherosclerosis. Cross-sections (n = 5195) were obtained at regular intervals from 329 arteries. For each artery, the cross-section that contained the least amount of plaque was considered to be the reference. For each cross-section, the percentage of lumen area decrease was expressed as a percentage of the lumen area at the reference site (luminal stenosis). Similarly, the area encompassed by the internal elastic lamina (IEL area) was expressed as a percentage of the IEL area at the reference site (relative IEL area). All cross-sections were categorized in three groups: relative IEL area > 105% (enlargement), 95% to 105% (no remodeling), and < 95% (shrinkage). The prevalence of enlargement (50% to 75%) was significantly higher compared with shrinkage (8% to 25%). Shrinkage was observed most frequently in the femoral arteries (25%) and infrequently in the renal arteries (8%). For all types of arteries, the relative IEL area correlated negatively with luminal stenosis (P < .001). Regression analysis of relative IEL area on luminal stenosis, however, showed significant differences in the first-order regression coefficients among artery types. On average, plaque increase was more compensated for by enlargement in the coronary, common carotid, and renal arteries compared with the arteries obtained from the lower extremities. Anatomic regional differences were observed in the impact of arterial wall remodeling on percent luminal stenosis in de novo atherosclerotic lesions.

Results of peripheral endovascular procedures in the operating room

PURPOSE

This study presents the results of closed (percutaneous) and open endovascular procedures performed exclusively by vascular surgeons in the operating room and compares them with results from combined series from the literature, including primarily closed procedures in radiology or cardiology facilities.

METHODS

Retrospective review of 607 consecutive peripheral arterial and venous angioplasties, stents, thrombolytic cases, and inferior vena caval filters in 446 patients was analyzed for immediate success rate, complication rate, and 1-year life table patency rate.

RESULTS

The incidence of initial technical success was: aorta, 89%; iliac artery, 91%; superficial femoral artery, 90%; popliteal artery, 91%; tibial arteries, 79%; arm arteries and veins, 86%; renal arteries, 100%; IVC filters, 98%; and iliofemoral veins, 100%. The 1-year primary patency rates, including technical failures, were 70.3% in 113 femoropopliteal procedures and 83.7% in 194 iliac arteries. Advantages to the use of the operating room included: (1) simultaneous angioplasty during a bypass operation for abnormalities proximal or distal to the graft, (2) correction of lesions first discovered during thrombectomy, and (3) optimum patient monitoring and sedation in the operating room.

CONCLUSIONS

Endovascular procedures performed by vascular surgeons in the operating room lead to results comparable with procedures performed in nonsurgical interventional suites, and the use of the operating room has advantages.

Endovascular remote endarterectomy in femoropopliteal occlusive disease: one-year clinical experience with the ring strip cutter device

OBJECTIVES

One-year clinical outcome of a new endovascular treatment for long segmental arterial occlusive disease using a ring strip cutter (RSC) to minimise surgical exposure.

DESIGN

Prospective, open study.

MATERIALS

Thirty-eight consecutive RSC procedures in 36 consecutive patients with lengthy occlusive (34) or multiple stenotic (4) femoropopliteal lesions were performed. Indications for operation were disabling claudication in 25 (66%), rest pain in 3 (8%), and gangrene in 10 (26%) patients.

METHODS

A newly developed endovascular ring strip cutter device was used to perform a remote endarterectomy through a single groin incision. Clinical data were analysed based on intention-to-treat.

RESULTS

Initial angiographic, clinical and haemodynamic success was achieved in all 38 (100%) limbs. Mean ankle-brachial index increased significantly from 0.62 +/- 0.14 to 1.02 +/- 0.14 postoperatively (p = 0.01). Four failures have occurred during follow-up. After one-year experience the cumulative (assisted) primary and secondary patency rates are 80% and 85% respectively. Duplex surveillance has detected progressive recurrent stenoses in 10 cases.

CONCLUSIONS

Remote endarterectomy of long segmental femoropopliteal occlusive disease through a single groin incision with the Ring Strip Cutter device is a safe and effective procedure. The early patency rates are good. Further long-term results are needed to evaluate this technique.