Implications of In Situ Thrombosis and Distal Embolization during Superficial Femoral Artery Endoluminal Intervention

Management of Acute Complications during Endovascular Procedures in Peripheral Arterial Disease: A Review

Endovascular therapy, as opposed to surgical bypass, has become the mainstay for peripheral arterial disease even in long segment occlusions. Complications can occur during the arterial access, catheter manipulation, balloon dilation, and/or stent placement. Given the high prevalence of comorbidities such as diabetes, hypertension, renal dysfunction, and coronary artery disease in these patients, early identification of procedural complications and initiation of treatment are of paramount importance. This review aims to provide comprehensive data on the identification and management of commonly encountered endovascular complications during endovascular interventions in peripheral arterial disease.

Extended Use of Distal Embolic Protection Devices in Treatment of Distal Embolism During Lower Extremity Arterial Endovascular Interventions

There is no consensus on the best treatment modality for acute distal embolization complications during endovascular interventions for peripheral arterial diseases. We report on 3 patients who underwent mechanical embolectomy using a distal embolic protection device (EPD). All patients showed angiographic evidence of distal embolism, which occurred during lower extremity limb salvage endovascular procedures. After embolectomy, all had complete recanalization of the involved vessel on completion angiogram, and none had any device-related complications or adverse outcomes from the embolization. This initial experience suggests that EPD can be used for both the prevention and treatment of intraoperative distal embolization during endovascular intervention of lower extremity arterial disease.

One-Year Clinical Outcome and Risk Factor Analysis of Directional Atherectomy Followed With Drug-Coated Balloon for Femoropopliteal Artery Disease

PURPOSE

This study investigated the 1-year clinical outcomes of directional atherectomy combined with drug-coated balloon (DA + DCB) in femoropopliteal artery disease (FPAD) from real-world experience.

MATERIALS AND METHODS

A retrospective study was conducted of patients treated between July 2016 and June 2019 using DA + DCB for FPAD. Patients' demographics, comorbidities, clinical characteristics and outcomes, and angiography and duplex ultrasound findings were analyzed. The 6-month and 1-year primary patency, primary assisted patency, secondary patency, and freedom from clinically-driven target lesion revascularization (CD-TLR) were evaluated. Univariate and multivariate analyses were performed to identify risk factors of primary patency loss or CD-TLR.

RESULTS

Seventy-nine consecutive patients (83 lesions, mean age 70.9 years, 52 men) were included. Twenty-seven limbs had lifestyle-limiting claudication and 56 limbs had critical limb ischemia. There were 73 and 10 limbs with de novo lesion and in-stent restenosis, respectively. The mean lesion length of all the patients was 22.1 cm. The mean length of chronic total occlusions (CTOs) was 8.3 cm. Severe calcification was found in 32.5% cases. The 1-year primary patency rate was 80.8% and freedom from CD-TLR was 92.2%. The bailout stenting rate was 2.4%. Patients with CTO >10 cm had significantly lower 1-year primary patency rate and freedom from CD-TLR than did patients with CTO ≤10 cm. Total length of CTO (stratified as ≤5 cm, 5-10 cm, >10 cm) was identified as an independent risk factor of 1-year primary patency loss and CD-TLR.

CONCLUSION

DA + DCB appears to be a safe and effective endovascular therapy to treat FPAD in real-world clinical practice, with a promising 1-year patency rate with a low rate of bailout stenting.

WIRION™ embolic protection system for carotid artery stenting and lower extremity endovascular intervention

Aim: To summarize all available literature regarding the Wirion™ embolic protection system (EPS) and present examples from our center. Materials & methods: A review of literture was performed about the utilization of Wirion EPS. Results: One study was identified investigating the outcomes of Wirion during carotid artery stenting. The study demonstrated 98.3% procedural success with stroke occurring in only 2.5%. Two single arm studies were identified investigating the efficacy of the Wirion filter during lower extremity endovascular interventions. The reported device success ranged from 95.1 to 97.3%. Conclusion: While carotid artery stenting should always be performed with adjunctive EPS in order to decrease the risk of cerebrovascular accidents, the routine use of EPS in femorpopliteal interventions remains an active area of investigation.

Long Chronic Total Occlusions: Revascularization Strategies

The treatment of chronic total occlusions (CTO) in patients with peripheral arterial disease (PAD) is a complex topic with multiple treatment techniques and treatment strategies. The interventionalist treating patients with PAD should have both a defined treatment algorithm and multiple techniques available for crossing these challenging lesions. This article will cover techniques for treating CTOs and provide an overview of current available evidence.

Current Status of Distal Embolization in Femoropopliteal Endovascular Interventions

The application of advanced endovascular techniques in very complex femoropopliteal atherosclerotic lesions has shown to expose patients to a higher risk of distal embolization (DE). This complication can affect both the short- and long-term outcomes, leading to worsening ischemia, early minor/major amputation, and longer hospital stay. Recently, there has been an increasing body of evidence on pathophysiology and clinical–radiological management of DE that however has not been systematically addressed by guidelines. The aim of this review was to analyze the current evidence outlining definition and classification, risk assessment, prevention, and management strategies of DE in femoropopliteal endovascular interventions.

An Algorithm for the Use of Embolic Protection During Atherectomy for Femoral Popliteal Lesions

OBJECTIVES

This study sought to identify an algorithm for the use of distal embolic protection on the basis of angiographic lesion morphology and vascular anatomy for patients undergoing atherectomy for femoropopliteal lesions.

BACKGROUND

Atherectomy has been shown to create more embolic debris than angioplasty alone. Distal embolic protection has been shown to be efficacious in capturing macroemboli; however, no consensus exists for the appropriate lesions to use distal embolic protection during atherectomy.

METHODS

Patients with symptomatic lower extremity peripheral artery disease treated with atherectomy and distal embolic protection were evaluated to identify potential predictors of DE. Plaque collected from the SilverHawk nose cone subset was sent to pathology for analysis to evaluate the accuracy of angiography in assessing plaque morphology.

RESULTS

Significant differences were found in lesion length (142.1 ± 62.98 vs. 56.91 ± 41.04; p = 0.0001), low-density lipoprotein (82.3 ± 40.3 vs. 70.9 ± 23.2; p = 0.0006), vessel runoff (1.18 ± 0.9 vs. 1.8 ± 0.9; p = 0.0001), chronic total occlusion (131 vs. 10; p = 0.001), in-stent restenosis (33 vs. 6; p = 0.0081), and calcified lesions (136 vs. 65; p < 0.001). In simple logistic regression analysis lesion length, reference vessel diameter, chronic total occlusion, runoff vessels, and in-stent restenosis were found to be strongly associated with macroemboli. Angiographic assessment of plaque morphology was accurate. Positive predictive value of 92.31, negative predictive value of 95.35, sensitivity of 92.31, and specificity of 95.35 for calcium; positive predictive value of 95.56, negative predictive value of 100, sensitivity of 100, and specificity of 92.31 for atherosclerotic plaque. Thrombus/in-stent restenosis was correctly predicted.

CONCLUSIONS

Chronic total occlusion, in-stent restenosis, thrombotic, calcific lesions >40 mm, and atherosclerotic lesions >140 mm identified by peripheral angiography necessitate concomitant filter use during atherectomy to prevent embolic complications.

The Relationship Between the Neutrophil-Lymphocyte Ratio and In-Stent Restenosis in Patients With Femoropopliteal Chronic Total Occlusions

We investigated the relationship between the neutrophil-lymphocyte ratio (NLR) and in-stent restenosis (ISR) in patients with femoropopliteal chronic total occlusions (CTOs). The study enrolled 180 patients who had undergone successful stenting treatment for femoropopliteal CTO. Patients with ISR were subsequently classified into 2 groups: early-ISR (within 1 year) and late-ISR (after 1 year). The clinical characteristics, angiographic data, and follow-up data were recorded. The baseline NLR was significantly higher in the early-ISR group than that in the non-ISR group [3.96(2.14) and 3.33(2.73), p = .04]. Receiver operating characteristic curve analysis suggested an optimum early ISR NLR cutoff point of 3.62, which showed a sensitivity and specificity of 73.4% and 80.4%, respectively (area under the curve: 0.707, 95% confidence interval: 0.603-0.792, P < .001). A subgroup analysis was performed based on the NLR value (<3.62 vs ≥3.62). In the NLR ≥3.62 subgroup, the incidence of early ISR was higher than that of late ISR ( P < .01). In the multivariate analysis, NLR ≥3.62 was independently and positively associated with a higher risk of early ISR. In conclusion, NLR is independently associated with early ISR after stent implantation in patients with femoropopliteal CTO.

Hospital Readmissions Following Endovascular Therapy for Critical Limb Ischemia: Associations With Wound Healing, Major Adverse Limb Events, and Mortality

BACKGROUND

The significance of hospital readmission after endovascular therapy for critical limb ischemia (CLI) is not well established. We sought to investigate the incidence, timing, and causes of readmissions after endovascular therapy for CLI and whether readmission is associated with major adverse limb events (MALE) or mortality.

METHODS AND RESULTS

This was a retrospective study of 252 patients treated with endovascular therapy for CLI. During median follow-up of 381 days (interquartile range [IQR], 115-718), 140 (56%) were readmitted, with median time to readmission of 83 days (IQR, 33-190). Readmission within 30 days occurred in 14% of patients (n=35; 25% of readmissions). Most readmissions occurred between 30 and 180 days (n=67; 48% of readmissions). The most frequent reason for readmission was unhealed wounds (n=63; 45% of readmissions). Independent predictors of readmission by Cox proportional hazards analysis were unhealed wounds, presence of multiple wounds, age ≥70, female sex, hemodialysis, and history of heart failure (P<0.05 for each). By Kaplan-Meier analysis, readmission was greatest in patients with unhealed wounds, followed by patients who never had a wound, and lowest in patients whose wounds completely healed (P<0.0001 overall, and P<0.01 between groups). After multivariable adjustment, readmission remained an independent predictor of composite MALE (major amputation, bypass, or endarterectomy) or mortality (adjusted hazard ratio, 3.1; 95% CI, 1.5-6.5; P=0.002).

CONCLUSIONS

Most readmissions occur 30 and 180 days after endovascular therapy for nonprocedural reasons. Unhealed wounds are an independent risk factor for readmission. Readmission is associated with increased MALE and mortality after endovascular therapy for CLI.

Complications and great escapes: equipment and techniques

All endovascular procedures have the potential for complications. The primary aims should always be avoidance of preventable complications and to minimize the impact of any complication. The core principles of an effective preventive strategy are: involving the interventional and clinical teams in a clear outline of the procedure and its potential adverse outcomes; ensuring an adequate inventory of required and backup equipment; the use of "time-out" to minimize wrong patient/wrong side adverse events; and an active audit program to identify areas of improvement. In the event of an adverse outcome there are many strategies that can be employed to rectify the situation or minimize the iatrogenic injury. This article provides a case-based discussion highlighting some of these techniques and how they can be used in a clinical setting.

Incidence, risk factors, treatment and prognosis of popliteal artery embolization in the superficial femoral artery interventions

Objective

Percutaneous transluminal angioplasty and stenting (PTA + stent) has gained acceptance as a primary treatment modality for the superficial femoral artery (SFA) diseases. Popliteal artery embolization (PAE) is a severe complication in SFA interventions. The purpose of this study was to evaluate the incidence, risk factors, treatment and prognosis of PAE in primary SFA PTA + stent.

Methods

Chronic SFA arteriosclerosis cases that underwent primary PTA + stent were reviewed from a retrospectively maintained database. Runoff vessels were evaluated in all cases before and after the interventions for PAE detection. The primary patency, secondary patency and limb salvage rates were calculated using Kaplan-Meier analysis and compared using log-rank analysis. Cox multivariate regression was performed to evaluate predictors of patency and limb salvage rates.

Results

There were 436 lesions treated in 388 patients with 10 PAE events (2.3%) in total. PAE rate was significantly higher in Transatlantic Inter-Society Consensus (TASC) C/D group compared with TASC A/B group (OR = 8.91, P = .002), in chronic total occlusion (CTO) lesions compared with stenotic lesions (P<.0001), and in group with history of cerebral ischemic stroke (OR = 6.11, P = .007). PAE rates were not significantly affected by age, sex, smoking, hypertension, diabetes, hyperlipidemia and runoff status. The binary logistic regression showed that only the TASC C/D was an independent predictor of PAE (P = .031). The 12-month and 24-month primary patency, secondary patency and limb salvage rates in PAE group showed no significant differences comparing with non-PAE group.

Conclusions

PAE is a rare event in primary SFA PTA + stent. TASC C/D lesion, CTO and cerebral ischemic stroke history are risk factors for PAE. PAE is typically reversible by comprehensive techniques. If the popliteal flow is restored in time, PAE has no significant effect on long-term patency and limb salvage rates.

Do thrombotic events during endovascular interventions lead to poorer outcomes in patients with severe limb ischemia?

INTRODUCTION

Intra-procedural acute thrombosis (IPAT) is a complication of endovascular procedures. We aim to identify risk factors for IPAT and compare the outcomes of patients with or without IPAT.

METHODS

Paired T test and χ (2) test were used to identify risk factors and short-term outcomes. Kaplan-Meier survival analysis was used for mid-term outcomes.

RESULTS

A total of 228 procedures were performed with 21 IPAT events (9.21%). The odds ratio of Indian patients developing IPAT was 2.8x (95% CI 1.1-7.6). Patients with in-stent occlusion or prior IPAT were 5.6x (95% CI 1.3-24.2) and 5.6x (95% CI 1.3-24.4) more likely to develop an IPAT event. Patients without IPAT had significantly more improvement in mean runoff score (-1.15 ± 1.31, p < 0.01). The odds of patients with IPAT requiring subsequent endovascular intervention and arterial bypass surgery were 4.2x (95% CI 1.6-10.7) and 7.1x (95% CI 1.9-27.0). There was no significant Kaplan-Meier estimated overall survival or amputation-free survival difference between patients with or without IPAT event.

CONCLUSION

Indian ethnicity, in-stent occlusion and previous IPAT were associated with higher risk of IPAT. Even after successful endovascular salvage, patients with IPATs were more likely to require secondary revascularization procedure. Patients with IPATs had no decrease in overall survival or amputation-free survival.

Effective endovascular treatment of calcified femoropopliteal disease with directional atherectomy and distal embolic protection: final results of the DEFINITIVE Ca⁺⁺ trial

Objectives

The purpose of the DEFINITIVE Ca⁺⁺ study was to evaluate the safety and effectiveness of directional atherectomy and distal embolic protection, used together to treat moderate to severely calcified femoropopliteal lesions.

Background

Despite advances in endovascular treatment modalities, treatment of calcified lesions remains a challenge.

Methods

A total of 133 subjects with 168 moderate to severely calcified lesions were enrolled. Lesions were treated with directional atherectomy devices, coupled with distal embolic protection.

Results

The 30-day freedom from MAE rate was 93.1%. Per angiographic core laboratory assessment, the primary effectiveness endpoint (≤50% residual diameter stenosis) was achieved in 92.0% (lower confidence bound of 87.6%) of lesions. By core lab analysis, these results did not achieve the success criteria (90%) for the primary effectiveness objective. Per site assessment, the objective was met with the endpoint being achieved in 97.0% (lower confidence bound 93.8%). A mean residual diameter stenosis of 33.3% was achieved with the directional atherectomy device. This was further decreased to 24.1% with the use of adjunctive therapy. The proportion of asymptomatic subjects [Rutherford Clinical Category (RCC) = 0] increased from 0% at baseline to 52.3% at the 30-day follow-up visit. In total, 88.5% of subjects experienced an improvement of one or more Rutherford categories.

Conclusions

The results of the DEFINITIVE Ca++ study demonstrate that the SilverHawk™ and TurboHawk™ atherectomy devices are safe and effective in the endovascular treatment of moderate to severely calcified lesions in the superficial femoral and/or popliteal arteries when used with the SpiderFX™ distal embolic protection device. © 2014 Wiley Periodicals, Inc.

Detection and treatment of acute thromboembolic events in the lower extremities

Acute procedural thromboembolic events are serious complications affecting both short- and long-term outcome. Patients at high risk include those undergoing catheter-based interventions for acute limb ischemia and long segment de novo or stented occlusions of the lower limb arteries. Additionally, debulking procedures and angioplasty/stenting of complex lesions in patients with advanced disease have also been associated with a higher risk of distal embolization and in situ thrombosis. This article includes a discussion of detection methods as well as preventive and treatment strategies.