Atherectomy for peripheral arterial disease

Pulsatile intravascular lithotripsy: A novel mechanism for peripheral artery calcium fragmentation and luminal expansion

OBJECTIVE

To assess the feasibility and treatment effect of pulsatile intravascular lithotripsy (PIVL) on calcified lesions in a cadaveric model of peripheral artery disease.

BACKGROUND

PIVL represents a novel potential approach to intravascular lithotripsy for the treatment of vascular calcification.

METHODS

In this preclinical device-feasibility study, technical success, calcium morphology and luminal expansion before and after PIVL treatment were evaluated in surgically isolated, perfused atherosclerotic lower-leg arteries and in perfused whole cadaveric lower legs. Analytical methods included micro-computed tomography (μCT), intravascular optical coherence tomography, digital subtraction angiography, and quantitative coronary analysis.

RESULTS

Treatment delivery was successful in all whole-leg specimens (N = 6; mean age 74.2, 66 % female) and in the 8 excised vessels with diameter appropriate to the PIVL balloon (2 vessels exceeding diameter specifications were excluded). There were no vessel perforations. After PIVL, excised vessels showed extensive evidence of new, full-thickness fractures in lesions with calcium arc exceeding 152° and with calcium wall thickness between 0.24 mm and 1.42 mm. PIVL fractures were observed in intimal nodules, sheets, shingles, and medial plates. Vessels within whole-leg specimens also showed full-thickness fracturing and a mean of 1.9 ± 0.9 mm in acute luminal gain, 101.6 ± 99.5 % gain in total minimum cross-sectional area, and a 31.7 ± 13.4 % relative reduction in stenosis (P < 0.001 for all analyses).

CONCLUSIONS

In a cadaveric model, PIVL treatment was technically feasible, fractured both circumferential and eccentric calcium lesions, and resulted in acute luminal gain. A clinical feasibility study of PIVL is currently enrolling.

Assessment of Patterns of Atherectomy Use

Background

Atherectomy has become the fastest growing catheter‐based peripheral vascular intervention performed in the United States, and overuse has been linked to increased reimbursement, but the patterns of use have not been well characterized.

Methods and Results

We used Blue Cross Blue Shield of Michigan Preferred Provider Organization and Medicare fee‐for‐service professional claims data from the Michigan Value Collaborative for patients undergoing office‐based laboratory atherectomy in 2019 to calculate provider‐specific rates of atherectomy use, reimbursement, number of vessels treated, and number of atherectomies per patient. We also calculated the rate that each provider converted a new patient visit to an endovascular procedure within 90 days. Correlations between parameters were assessed with simple linear regression. Providers completing ≥20 office‐based laboratory atherectomies and ≥20 new patient evaluations during the study period were included. A total of 59 providers performing 4060 office‐based laboratory atherectomies were included. Median professional reimbursement per procedure was $4671.56 (interquartile range [IQR], $2403.09–$7723.19) from Blue Cross Blue Shield of Michigan and $14 854.49 (IQR, $9414.80–$18 816.33) from Medicare, whereas total professional reimbursement from both payers ranged from $2452 to $6 880 402 per year. Median 90‐day conversion rate was 5.0% (IQR, 2.5%–10.0%), whereas the median provider‐level average number of vessels treated per patient was 1.20 (IQR, 1.13–1.31) and the median provider‐level average number of treatments per patient was 1.38 (IQR, 1.26–1.63). Total annual reimbursement for each provider was directly correlated with new patient‐procedure conversion rate ( R 2 =0.47; P <0.001), mean number of vessels treated per patient ( R 2 =0.31; P <0.001), and mean number of treatments per patient ( R 2 =0.33; P <0.001).

Conclusions

A minority of providers perform most procedures and are reimbursed substantially more per procedure compared with most providers. Procedural conversion rate, number of vessels, and number of treatments per patient represent potential policy levers to curb overuse.

Effects of Peripheral Arterial Disease Interventions on Survival: A Propensity-Score Matched Analysis Using VQI Data

BACKGROUND

Atherectomy is currently being used extensively for occlusive peripheral artery disease (PAD) interventions without proven benefits. This analysis examines the effects of atherectomy and other endovascular interventions on patient survival.

OBJECTIVES

The aim of this study is to compare overall survival for patients undergoing PAD endovascular interventions, such as plain old balloon angioplasty (POBA), stent deployment and atherectomy.

METHODS

Propensity score matched cohorts were constructed to conduct pairwise comparisons of overall survival in patients who underwent stenosis and occlusive PAD interventions between May 2011 and February 2020 using Vascular Quality Initiative (VQI) regional registry data. Inverse probability treatment weighting method was used to compare secondary outcomes of in-hospital mortality, length of stay, complications and major amputations. Comparative analysis was performed for POBA vs stenting, POBA vs atherectomy, and stenting vs atherectomy.

RESULTS

A total number of 15281 eligible cases were identified. After propensity score matching, 6094, 4032, and 3312 cases were used to compare POBA versus stent deployment, POBA versus atherectomy and stent versus atherectomy, respectively. Stent deployment had significantly better overall survival compared with POBA and atherectomy (P < 0.001). Multivariable Cox proportional hazard models suggested stenting was associated with a reduction in mortality hazard by 30% compared with POBA (HR: 0.7; 95% CI: 0.6-0.82; P < 0.001) and a 40% mortality reduction compared with atherectomy (HR: 0.6; 95% CI: 0.48-0.75; P < 0.001). No significant difference was found between POBA and atherectomy. There was no statistical difference in other secondary outcomes which were comparable among all cohorts.

CONCLUSIONS

Stent deployment was significantly superior to POBA and atherectomy in terms of overall survival with comparable complication and amputation rates. The natural history of PAD patients presenting with claudication is associated with an extremely low annual mortality risk. Therefore, further examinations of outcomes, especially in regards to mortality rates, both POBA and atherectomy on the management of PAD patients especially those presenting with claudication is warranted.

Critical Appraisal of the Contemporary Use of Atherectomy to Treat Femoral-Popliteal Atherosclerotic Disease

OBJECTIVE

Atherectomy has become increasingly used as an endovascular treatment of lower extremity atherosclerotic disease in the United States. Concerns and controversies about its indication and outcomes exist. The goal of this systematic review and meta-analysis was to investigate the outcomes and complications related to atherectomy to treat femoropopliteal atherosclerotic disease.

METHODS

A systematic review following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was performed. Four major scientific repositories, MEDLINE, EMBASE, The Cochrane Library, and Thompson Web of Sciences were queried from their inception to April 5, 2020. Data was reviewed and entered in a dedicated dataset by the investigators. Outcomes included patency rates, clinical and hemodynamic improvement, and morbidity and mortality associated with atherectomy interventions.

RESULTS

Twenty-four studies encompassing 1900 patients met inclusion criteria for this study. 74.3% of patients presented with Rutherford class (RC) 1-3 and 25.7% presented with RC class 4-6. 1445 patients underwent atherectomy, and 455 patients were treated without atherectomy. Atherectomy patients underwent directional atherectomy (DA, n = 851), rotational atherectomy (RA, n = 851), laser atherectomy (LA, n = 201), and orbital atherectomy (OA, n = 78). The majority of patients additionally received adjunct treatments which were variable across studies and included a combination of stenting, balloon angioplasty (BA), or drug coated balloon (DCB) angioplasty. Technical success was achieved in 92.3% of cases. Distal embolization, vessel perforation, and dissection occurred in 3.4%, 1.9%, and 4% of cases respectively. Initial patency was 95.4% and at 12-month median follow up primary patency was 72.6%. ABI improved from pre-operative mean of 0.6 to post-operative mean of 0.84. Incidence of major amputation and mortality over the follow up period was 2.2% and 3.4% respectively.

CONCLUSIONS

This review of the published data suggests that femoropopliteal atherectomy can be completed safely while modestly improving ABIs and maintaining one-year patency in nearly three out of four patients; however, this is based on heterogeneous studies that skew generalizable conclusions about atherectomy's efficacy. Atherectomy places a high cost burden on the healthcare system and is utilized in the United States at a higher rate than in other countries. Our review of the literature does not demonstrate clear atherectomy superiority to alternatives that would warrant pervasive and increasing use of this costly technology. Future work should focus on developing high quality randomized controlled trials to determine specific patient and lesion characteristics in which atherectomy can add value.

Influence of Infrapopliteal Runoff Vessels on Primary Patency after Superficial Femoral Artery Angioplasty with Stenting in Patients with Claudication

Purpose

The number of infrapopliteal runoff vessels seems to be one of the factors influencing arterial patency in patients who had undergone superficial femoral artery (SFA) angioplasty with stenting. However, the effectiveness of infrapopliteal runoff vessels in predicting patency during SFA angioplasty remains unclear. This study aimed to determine whether the number and quality of infrapopliteal runoff vessels affect the primary patency after SFA angioplasty with stenting in patients with claudication.

Methods

Materials and This study reviewed a retrospective database of patients with claudication who underwent SFA angioplasty with stenting between March 2011 and December 2016. The preoperative computed tomography findings of all patients were reviewed to assess infrapopliteal runoff vessels. The Trans-Atlantic Inter-Society (TASC) II classification and modified Society for Vascular Surgery (SVS) runoff score were used for subsequent analysis. Kaplan–Meier survival curves were constructed, and Fisher’s exact and chi-square tests were used for data analysis.

Results

A total of 153 limbs of 122 patients (88.2% male, mean age: 69.1 years) underwent SFA angioplasty with stenting. The overall primary patency rates of TASC II A/B and C/D cases were 77.1% and 31.2%, respectively, at 36 months (P<0.001). The primary patency rates at 36 months using the modified SVS runoff scoring system were 64.6% and 49.8% for the good-to-compromised (≤9 points) and poor (≥10 points) runoff groups, respectively (P=0.011).

Conclusion

The modified SVS runoff scoring system is effective in predicting primary patency after SFA angioplasty with stenting in patients treated for claudication.

Endovascular interventions for claudication do not meet minimum standards for the Society for Vascular Surgery efficacy guidelines

OBJECTIVE

Because the treatment of intermittent claudication (IC) is elective, good short- and long-term outcomes are imperative. The objective of the present study was to examine the outcomes of endovascular management of IC reported in the Vascular Quality Initiative and compare them with the Society for Vascular Surgery guidelines for IC treatment to determine whether real-world results are within the guidelines.

METHODS

Patients undergoing peripheral vascular intervention for IC from 2004 to 2017 with complete data and >9 month follow-up were included. The primary outcome measures were IC recurrence and repeat procedures performed ≤2 years after the initial treatment.

RESULTS

A total of 16,152 patients met the inclusion criteria, with a mean age of 66 years. Of the 16,152 patients, 61% were men, 45% were current smokers, and 28% had been discharged without antiplatelet or statin medication. Adjusted analyses revealed that treatment of more than two arteries was associated with a shorter time to IC recurrence (hazard ratio [HR], 1.19; 95% confidence interval [CI], 1.09-1.31) and a shorter time to repeat procedures (HR, 1.25; 95% CI, 1.09-1.45). The use of atherectomy was also associated with a shorter time to IC recurrence (HR, 1.29; 95% CI, 1.08-1.33) and a shorter time to repeat procedures (HR, 1.31; 95% CI, 1.13-1.52). Discharge with antiplatelet and statin medications was associated with a longer time to IC recurrence (HR, 0.84; 95% CI, 0.78-0.91) and a longer time to repeat procedures (HR, 0.77; 95% CI, 0.69-0.87). Life-table analysis at 2 years revealed that only 32% of patients were free from IC recurrence, although 76% had not undergone repeat procedures. Stratified by anatomic treatment level, 37% of isolated aortoiliac interventions, 22% of aortoiliac and femoropopliteal interventions, 30% of isolated femoropopliteal interventions, and 20% of femoropopliteal and tibial interventions had remained free from IC recurrence at 2 years.

CONCLUSIONS

Most patients treated with an endovascular approach to IC did not meet the Society for Vascular Surgery guidelines for long-term freedom from recurrent symptoms of >50% at 2 years. Many lacked preprocedure optimization of medical management. The use of atherectomy and treatment of more than two arteries were associated with poor outcomes after peripheral vascular intervention for IC, because only 32% of these patients were free from recurrent symptoms at 2 years. Even when risk factor modification is optimized before the procedure, vascular specialists should be aware of the association between atherectomy and multivessel interventions with poorer long-term outcomes and counsel patients appropriately before intervention.

Fabrication of New Hybrid Scaffolds for in vivo Perivascular Application to Treat Limb Ischemia

Cell therapies are emerging as a new therapeutic frontier for the treatment of ischemic disease. However, femoral occlusions can be challenging environments for effective therapeutic cell delivery. In this study, cell-engineered hybrid scaffolds are implanted around the occluded femoral artery and the therapeutic benefit through the formation of new collateral arteries is investigated. First, it is reported the fabrication of different hybrid “hard-soft” 3D channel-shaped scaffolds comprising either poly(ε-caprolactone) (PCL) or polylactic-co-glycolic acid (PLGA) and electro-spun of gelatin (GL) nanofibers. Both PCL-GL and PLGA-GL scaffolds show anisotropic characteristics in mechanical tests and PLGA displays a greater rigidity and faster degradability in wet conditions. The resulting constructs are engineered using human adventitial pericytes (APCs) and both exhibit excellent biocompatibility. The 3D environment also induces expressional changes in APCs, conferring a more pronounced proangiogenic secretory profile. Bioprinting of alginate-pluronic gel (AG/PL), containing APCs and endothelial cells, completes the hybrid scaffold providing accurate spatial organization of the delivered cells. The scaffolds implantation around the mice occluded femoral artery shows that bioengineered PLGA hybrid scaffold outperforms the PCL counterpart accelerating limb blood flow recovery through the formation arterioles with diameters >50 μm, demonstrating the therapeutic potential in stimulating reparative angiogenesis.

Atherectomy for peripheral arterial disease

BACKGROUND

Symptomatic peripheral arterial disease (PAD) has several treatment options, including angioplasty, stenting, exercise therapy, and bypass surgery. Atherectomy is an alternative procedure, in which atheroma is cut or ground away within the artery. This is the first update of a Cochrane Review published in 2014.

OBJECTIVES

To evaluate the effectiveness of atherectomy for peripheral arterial disease compared to other established treatments.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and Allied and Complementary Medicine (AMED) databases, and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 12 August 2019.

SELECTION CRITERIA

We included all randomised controlled trials that compared atherectomy with other established treatments. All participants had symptomatic PAD with either claudication or critical limb ischaemia and evidence of lower limb arterial disease.

DATA COLLECTION AND ANALYSIS

Two review authors screened studies for inclusion, extracted data, assessed risk of bias and used GRADE criteria to assess the certainty of the evidence. We resolved any disagreements through discussion. Outcomes of interest were: primary patency (at six and 12 months), all-cause mortality, fatal and non-fatal cardiovascular events, initial technical failure rates, target vessel revascularisation rates (TVR; at six and 12 months); and complications.

MAIN RESULTS

We included seven studies, with a total of 527 participants and 581 treated lesions. We found two comparisons: atherectomy versus balloon angioplasty (BA) and atherectomy versus BA with primary stenting. No studies compared atherectomy with bypass surgery. Overall, the evidence from this review was of very low certainty, due to a high risk of bias, imprecision and inconsistency. Six studies (372 participants, 427 treated lesions) compared atherectomy versus BA. We found no clear difference between atherectomy and BA for the primary outcomes: six-month primary patency rates (risk ratio (RR) 1.06, 95% confidence interval (CI) 0.94 to 1.20; 3 studies, 186 participants; very low-certainty evidence); 12-month primary patency rates (RR 1.20, 95% CI 0.78 to 1.84; 2 studies, 149 participants; very low-certainty evidence) or mortality rates (RR 0.50, 95% CI 0.10 to 2.66, 3 studies, 210 participants, very low-certainty evidence). One study reported cardiac failure and acute coronary syndrome as causes of death at 24 months but it was unclear which arm the participants belonged to, and one study reported no cardiovascular events. There was no clear difference when examining: initial technical failure rates (RR 0.48, 95% CI 0.22 to 1.08; 6 studies, 425 treated vessels; very low-certainty evidence), six-month TVR (RR 0.51, 95% CI 0.06 to 4.42; 2 studies, 136 treated vessels; very low-certainty evidence) or 12-month TVR (RR 0.59, 95% CI 0.25 to 1.42; 3 studies, 176 treated vessels; very low-certainty evidence). All six studies reported complication rates (RR 0.69, 95% CI 0.28 to 1.68; 6 studies, 387 participants; very low-certainty evidence) and embolisation events (RR 2.51, 95% CI 0.64 to 9.80; 6 studies, 387 participants; very low-certainty evidence). Atherectomy may be less likely to cause dissection (RR 0.28, 95% CI 0.14 to 0.54; 4 studies, 290 participants; very low-certainty evidence) and may be associated with a reduction in bailout stenting (RR 0.26, 95% CI 0.09 to 0.74; 4 studies, 315 treated vessels; very low-certainty evidence). Four studies reported amputation rates, with only one amputation event recorded in a BA participant. We used subgroup analysis to compare the effect of plain balloons/stents and drug-eluting balloons/stents, but did not detect any differences between the subgroups. One study (155 participants, 155 treated lesions) compared atherectomy versus BA and primary stenting, so comparison was extremely limited and subject to imprecision. This study did not report primary patency. The study reported one death (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence) and three complication events (RR 7.04, 95% CI 0.80 to 62.23; 155 participants; very low-certainty evidence) in a very small data set, making conclusions unreliable. We found no clear difference between the treatment arms in cardiovascular events (RR 0.38, 95% CI 0.04 to 3.23; 155 participants; very low-certainty evidence). This study found no initial technical failure events, and TVR rates at six and 24 months showed little difference between treatment arms (RR 2.27, 95% CI 0.95 to 5.46; 155 participants; very low-certainty evidence and RR 2.05, 95% CI 0.96 to 4.37; 155 participants; very low-certainty evidence, respectively).

AUTHORS' CONCLUSIONS

This review update shows that the evidence is very uncertain about the effect of atherectomy on patency, mortality and cardiovascular event rates compared to plain balloon angioplasty, with or without stenting. We detected no clear differences in initial technical failure rates or TVR, but there may be reduced dissection and bailout stenting after atherectomy although this is uncertain. Included studies were small, heterogenous and at high risk of bias. Larger studies powered to detect clinically meaningful, patient-centred outcomes are required.

Long-Term Patency and Clinical Outcomes of Nitinol Stenting for Femoropopliteal Atherosclerotic Disease

BACKGROUND

Treatment of peripheral arterial disease (PAD) has become increasingly dominated by endovascular interventions. The short-term outcomes of endovascular therapy have been well studied, but late outcomes remain largely unpublished; in this series, we report the late outcomes of primary nitinol stenting.

METHODS

All patients undergoing primary nitinol stenting of the superficial femoral artery (SFA) and/or popliteal artery (PA) during a 10-year period by a single surgeon (S.K.) were reviewed. No attempts were made on patients with orificial or total occlusion of the SFA, PA, and proximal tibial arteries. Differences in primary patency, primary-assisted patency, secondary patency, and freedom from bypass were evaluated at 1, 5, and 9 years.

RESULTS

A total of 294 limbs in 240 patients were treated. One hundred and thirty additional endovascular procedures were observed during the study period averaging to 0.16 endovascular interventions per limb per year. Primary patency in TASC A/B limbs at 1, 5, and 9 years was 79%, 35%, and 19%, respectively, and in TASC C/D limbs was 62%, 11%, and 3%, respectively. Secondary patency in TASC A/B limbs at 1, 5, and 9 years was 96%, 81%, and 65%, respectively, and in TASC C/D limbs was 92%, 64%, and 41%, respectively. Freedom from bypass in TASC A/B limbs at 1, 5, and 9 years was 98%, 89%, and 85%, respectively, and in TASC C/D limbs was 95%, 78%, and 69%, respectively. Five below-the-knee amputations were observed during the study period.

CONCLUSIONS

An endovascular-first approach can be applied to the vast majority of femoropopliteal lesions. While the late outcomes of TASC C/D lesions are inferior to those of TASC A/B lesions, an endovascular-first approach still provides durable outcomes.

Adverse Events After Atherectomy: Analyzing Long-Term Outcomes of Endovascular Lower Extremity Revascularization Techniques

Background The long-term effectiveness of atherectomy treatment for peripheral arterial disease is unknown. We studied 5-year clinical outcomes by endovascular treatment type among patients with peripheral arterial disease. Methods and Results We queried the Medicare-linked VQI (Vascular Quality Initiative) registry for endovascular interventions from 2010 to 2015. The exposure was treatment type: atherectomy (with or without percutaneous transluminal angioplasty [ PTA] ), stent (with or without PTA ), or PTA alone. The outcomes were major amputation, any amputation, and major adverse limb event (major amputation or any reintervention). We used the center-specific proportions of atherectomy procedures performed in the 12 months before a patient's procedure as the instruments to perform an instrumental-variable Cox model analysis. Among 16 838 eligible patients (median follow-up: 1.3-1.5 years), 11% underwent atherectomy, 40% received PTA alone, and 49% underwent stenting. Patients receiving atherectomy commonly underwent femoropopliteal artery treatment (atherectomy: 65%; PTA : 49%; stenting: 43%; P<0.001) and had worse disease severity (Trans-Atlantic Inter-Society Consensus score [TASC] B and greater; atherectomy: 77%; PTA : 68%; stenting: 67%; P<0.001). The 5-year rate of major adverse limb events was 38% in patients receiving atherectomy versus 33% for PTA and 32% for stenting (log rank P<0.001). Controlling for unmeasured confounding using instrumental-variable analysis, patients treated with atherectomy experienced outcomes similar to those of patients treated with PTA , except for a higher risk of any amputation (hazard ratio: 1.51; 95% CI , 1.08-2.13). However, compared with stenting, atherectomy patients had a higher risk of major amputation (hazard ratio: 3.66; 95% CI , 1.72-7.81), any amputation (hazard ratio: 2.73; 95% CI , 1.60-4.76), and major adverse limb event (hazard ratio: 1.61; 95% CI , 1.10-2.38). Conclusions Atherectomy is used to treat severe femoropopliteal and tibial peripheral arterial disease even though long-term adverse outcomes occur more frequently after this treatment modality.

Critical limb ischemia: current challenges and future prospects

Critical limb ischemia (CLI) is considered the most severe pattern of peripheral artery disease. It is defined by the presence of chronic ischemic rest pain, ulceration or gangrene attributable to the occlusion of peripheral arterial vessels. It is associated with a high risk of major amputation, cardiovascular events and death. In this review, we presented a complete overview about physiopathology, diagnosis and holistic management of CLI. Revascularization is the first-line treatment, but several challenging cases are not treatable by conventional techniques. Unconventional techniques for the treatment of complex below-the-knee arterial disease are described. Furthermore, the state-of-the-art on gene and cell therapy for the treatment of no-option patients is reported.

Outcomes of infrapopliteal angioplasty for limb salvage based on the updated TASC II classification

PURPOSE

We aimed to evaluate limb salvage, defined as freedom from major amputation, and to identify predictors of major amputation in patients with infrapopliteal peripheral arterial disease (PAD) based on the updated 2015 TASC II anatomic classification treated by percutaneous transluminal angioplasty (PTA).

METHODS

This was a retrospective study of infrapopliteal PTA procedures performed for PAD over a 4-year period. Patient demographics, medical comorbidities, risk factors, angiographic imaging, technical details, and clinical follow-up were analyzed to determine limb salvage rates, technical success, and all-cause mortality. Predictors of major amputation following PTA were identified.

RESULTS

A total of 112 patients were treated by infrapopliteal PTA. Most lesions consisted of TASC C (44%) and D (34%) categories, were over 10 cm in length, and were occlusive and heavily calcified (89%). Overall technical success was 75%, with limb salvage rates of 77% at 1 year and 65% at 3 years following PTA. Smoking, previous stroke or cardiovascular events, and anticoagulation use were associated with an increased risk of major amputation following PTA.

CONCLUSION

PTA of complex infrapopliteal PAD is associated with good intermediate term limb salvage rates.

Atherectomy-Associated Complications in the Southern California Vascular Outcomes Improvement Collaborative

BACKGROUND

Atherectomy has become an increasingly utilized modality for the endovascular treatment of peripheral arterial occlusive disease. The objective of this study was to determine the incidence and risk factors for atherectomy-associated complications.

METHODS

A retrospective review was performed for all atherectomy procedures performed between January 2011 and December 2015 in the Southern California Vascular Outcomes Improvement Collaborative. Atherectomy was defined as laser, orbital, or excisional atherectomy. Complications were dissection, perforation, and distal embolization.

RESULTS

Seven hundred twenty-nine atherectomy procedures were performed at 7 institutions by 27 practitioners. The mean age was 73 years with 415 (57%) males. Four hundred nineteen (57%) were diabetic, 673 (92%) hypertensive, 457 (63%) smokers, and 244 (34%) had coronary artery disease. Dissection occurred in 51 (7%) procedures, embolization in 23 (3.1%), and perforation in 12 (1.6%). The mean number of lesions treated per artery was the same at 1.6 in patients with any complication and no complication (P = 0.77). The total occluded length was 7.4 cm for complications versus 7.2 cm for no complication (P = 0.73). The total treated length was 12.9 cm for complications versus 11.3 cm for no complication (P = 0.03). The incidence of complications for Trans-Atlantic Inter-Society Consensus (TASC) C/D lesions were 13% compared to 10% for TASC A/B lesions (P = 0.05). The incidence of complications in superficial femoral/popliteal lesions was 12.9% vs. 10.4% in tibial lesions (P = 0.13). In multivariable analysis, treatment length was associated with a small increased risk of complication (odds ratio = 1.02, 95% confidence interval = 1.0-1.04).

CONCLUSIONS

Increased treatment length is associated with an increased risk of atherectomy-associated complications. Demographic factors and comorbidities were not predictors of complications.

Cost-effectiveness analysis of drug-coated therapies in the superficial femoral artery

OBJECTIVE

Drug-coated balloons (DCBs) may increase durability of endovascular treatment of superficial femoral artery (SFA) disease while avoiding stent-related risks. The purpose of this study was to use meta-analytic data of DCB studies to compare the cost-effectiveness of potential SFA treatments: DCB, drug-eluting stent (DES), plain old balloon angioplasty (POBA), or bare-metal stent (BMS).

METHODS

A search for randomized controlled trials comparing DCB with POBA for treatment of SFA disease was performed. Hazard ratios were extracted to account for the time-to-event primary outcome of target lesion revascularization. Odds ratios were calculated for the secondary outcomes of primary patency (PP) and major amputation. Incorporating pooled data from the meta-analysis, cost-effectiveness analysis, assuming a payer perspective, used a decision model to simulate patency at 1 year and 2 years for each index treatment modality: POBA, BMS, DCB, or DES. Costs were based on current Medicare outpatient reimbursement rates.

RESULTS

Eight studies (1352 patients) met inclusion criteria for meta-analysis. DCB outperformed POBA with respect to target lesion revascularization over time (pooled hazard ratio, 0.41; P < .001). Risk of major amputation at 12 months was not significantly different between groups. There was significantly improved 1-year PP in the DCB group compared with POBA (pooled odds ratio, 3.30; P < .001). In the decision model, the highest PP at 1 year was seen in the DES index therapy strategy (79%), followed by DCB (74%), BMS (71%), and POBA (64%). With a baseline cost of $9259.39 per patent limb at 1 year in the POBA-first group, the incremental cost per patent limb for each other strategy compared with POBA was calculated: $14,136.10/additional patent limb for DCB, $38,549.80/limb for DES, and $59,748,85/limb for BMS. The primary BMS option is dominated by being more expensive and less effective than DCB. Compared directly with DCB, DES costs $87,377.20 per additional patent limb at 1 year. Based on the projected PP at 1 year in the decision model, the number needed to treat for DES compared with DCB is 20. At current reimbursement, the use of more than two DCBs per procedure would no longer be cost-effective compared with DES. At 2 years, DCB emerges as the most cost-effective index strategy with the lowest overall cost and highest patency rates over that time horizon.

CONCLUSIONS

Current data and reimbursements support the use of DCB as a cost-effective strategy for endovascular intervention in the SFA; any additional effectiveness of DES comes at a high price. Use of more than one DCB per intervention significantly decreases cost-effectiveness.

Management of Critical Limb Ischemia

Critical limb ischemia (CLI) is a clinical syndrome of ischemic pain at rest or tissue loss, such as nonhealing ulcers or gangrene, related to peripheral artery disease. CLI has a high short-term risk of limb loss and cardiovascular events. Noninvasive or invasive angiography help determine the feasibility and approach to arterial revascularization. An endovascular-first approach is often advocated based on a lower procedural risk; however, specific patterns of disease may be best treated by open surgical revascularization. Balloon angioplasty and stenting form the backbone of endovascular techniques, with drug-eluting stents and drug-coated balloons offering low rates of repeat revascularization. Combined antegrade and retrograde approaches can increase success in long total occlusions. Below the knee, angiosome-directed angioplasty may lead to greater wound healing, but failing this, any straight-line flow into the foot is pursued. Hybrid surgical techniques such as iliac stenting and common femoral endarterectomy are commonly used to reduce operative risk. Lower extremity bypass grafting is most successful with a good quality, long, single-segment autogenous vein of at least 3.5-mm diameter. Minor amputations are often required for tissue loss as a part of the treatment strategy. Major amputations (at or above the ankle) limit functional independence, and their prevention is a key goal of CLI therapy. Medical therapy after revascularization targets risk factors for atherosclerosis and assesses wound healing and new or recurrent flow-limiting disease. The ongoing National Institutes of Health-sponsored Best Endovascular Versus Best Surgical Therapy in Patients With Critical Limb Ischemia (BEST-CLI) study is a randomized trial of the contemporary endovascular versus open surgical techniques in patients with CLI.

Endovascular intervention for peripheral artery disease

Advances in endovascular therapies during the past decade have broadened the options for treating peripheral vascular disease percutaneously. Endovascular treatment offers a lower risk alternative to open surgery in many patients with multiple comorbidities. Noninvasive physiological tests and arterial imaging precede an endovascular intervention and help localize the disease and plan the procedure. The timing and need for revascularization are broadly related to the 3 main clinical presentations of claudication, critical limb ischemia, and acute limb ischemia. Many patients with claudication can be treated by exercise and medical therapy. Endovascular procedures are considered when these fail to improve quality of life and function. In contrast, critical limb ischemia and acute limb ischemia threaten the limb and require more urgent revascularization. In general, endovascular treatments have greater long-term durability for aortoiliac disease than femoral popliteal disease. Infrapopliteal revascularization is generally reserved for critical and acute limb ischemia. Balloon angioplasty and stenting are the mainstays of endovascular therapy. New well-tested innovations include drug-eluting stents and drug-coated balloons. Adjunctive devices for crossing chronic total occlusions or debulking plaque with atherectomy are less rigorously studied and have niche roles. Patients receiving endovascular procedures need a structured surveillance plan for follow-up care. This includes intensive treatment of cardiovascular risk factors to prevent myocardial infarction and stroke, which are the main causes of death. Limb surveillance aims to identify restenosis and new disease beyond the intervened segments, both of which may jeopardize patency and lead to recurrent symptoms, functional impairment, or a threatened limb.

Role of the latest endovascular technology in the treatment of intermittent claudication

Intermittent claudication is a serious symptom in patients with peripheral arterial disease, and severely limits activities of daily living. Conservative treatment (optimal medical therapy and exercise rehabilitation programs) and revascularization procedures (endovascular treatment [EVT] or open bypass surgery) can relieve intermittent claudication. Among these treatment options, EVT has developed dramatically during the past decade, and has enabled physicians to offer less invasive treatment options with increasing durability. EVT for aortoiliac lesions has matured, and its long-term patency now approaches that of open bypass surgery. The latest EVT technologies include drug-eluting stents, stent grafts, drug-coated balloons, and bioresorbable stents. The recently reported patency of stent grafts in the femoropopliteal lesions was comparable with that of the prosthetic bypass graft. In the course of the paradigm shift from bypass surgery to EVT, evidence of any long-term benefit of EVT compared with supervised exercise is still inconclusive. EVT could improve walking performance in the short-term, while supervised exercise could improve walking performance more efficiently in the long-term. Combined treatment with EVT and exercise may offer the most sustainable and effective symptom relief. This paper reviews the relevant literature on the treatment of intermittent claudication, focusing on the latest EVT technologies, and outlines a strategy for achieving long-term benefits.