Prospective trial of infrapopliteal artery balloon angioplasty for critical limb ischemia: angiographic and clinical results

Randomized clinical trial to compare the efficacy of self-expanding bare metal nitinol stent and balloon angioplasty alone for below-the-knee lesions following successful balloon angioplasty: 1-year clinical outcomes

This prospective, multicenter, randomized study aimed to compare the 1-year clinical outcomes after primary stenting with self-expanding bare metal nitinol stent (SENS) and plain old balloon angioplasty (POBA) in patients with critical limb ischemia (CLI) and below-the-knee (BTK) lesions. Overall, 119 patients with CLI and BTK lesions were randomized to POBA alone (POBA group, 61 patients) or primary stenting with SENS (stenting group, 58 patients) after achieving acceptable POBA results in target BTK lesions. Clinical outcomes including amputation and revascularization rates were prospectively compared for 1 year. After 1 year, similar incidence rates of individual clinical endpoints, including cardiac death (6.5% vs. 5.1%, p > 0.999), myocardial infarction (1.6% vs. 0.0%, p > 0.999), repeat revascularization (19.6% vs. 18.9%, p = 0.922), target lesion revascularization (13.1% vs. 17.2%, p = 0.530), and amputation (4.9% vs. 0.0%, p = 0.244), were observed. POBA appeared to have acceptable treatment outcomes compared with primary stenting with SENS after 1 year in CLI patients with BTK lesions undergoing percutaneous transluminal angioplasty (PTA).

Verification of Therapeutic Effect through Accelerator Mass Spectrometry-Based Single Cell Level Quantification of hESC-Endothelial Cells Distributed into an Ischemic Model

As the potential of pluripotent stem cell-derived differentiated cells has been demonstrated in regenerative medicine, differentiated vascular endothelial cells (ECs) are emerging as a therapeutic agent for the cardiovascular system. To verify the therapeutic efficacy of differentiated ECs in an ischemic model, human embryonic stem cells (hESCs) are induced as EC lineage and produce high-purity ECs through fluorescence-activated cell sorting (FACS). When hESC-ECs are transplanted into a hindlimb ischemic model, it is confirmed that blood flow and muscle regeneration are further improved by creating new blood vessels together with autologous ECs than the primary cell as cord blood endothelial progenitor cells (CB-EPCs). In addition, previously reported studies show the detection of transplanted cells engrafted in blood vessels through various tracking methods, but fail to provide accurate quantitative values over time. In this study, it is demonstrated that hESC-ECs are engrafted approximately sevenfold more than CB-EPCs by using an accelerator mass spectrometry (AMS)-based cell tracking technology that can perform quantification at the single cell level. An accurate quantification index is suggested. It has never been reported in in vivo kinetics of hESC-ECs that can act as therapeutic agents.

Crossing complex infrapopliteal lesions utilizing a front-end cutting technique: A report of two cases with a novel rotational atherectomy device

Critical limb ischemia represents the most severe stage of peripheral vascular disease and patients often present with complex, calcified infrapopliteal lesions. Atherectomy is an endovascular treatment modality that can be used to debulk otherwise uncrossable lesions. We performed a retrospective, single-center, case report of two patients who presented with critical limb ischemia and whose complex and calcified infrapopliteal lesions were treated with the 1.5 mm Phoenix Atherectomy System after prior failed angioplasty attempts. The 1.5 mm Phoenix Atherectomy System successfully debulked each infrapopliteal lesion, and each patient achieved thrombolysis in myocardial infarction grade 3 flow of the target lesion. There were no device-related procedural complications or deaths. These cases demonstrate that the Phoenix Atherectomy System can be used to debulk complex, calcified infrapopliteal lesions to optimize endovascular treatment and improve outcomes for patients with critical limb ischemia. Further studies are warranted to validate the long-term safety and efficacy rates of the Phoenix Atherectomy System in a larger critical limb ischemia population.

How I do it: Pedal access and pedal loop revascularization for patients with chronic limb-threatening ischemia

An increasing proportion of patients with chronic limb-threatening ischemia are older and have multiple comorbidities, including diabetes and renal failure. For those who are not candidates for a surgical bypass, this set of patients presents a challenge to vascular surgeons and interventionalists owing to the complex below-the-knee and increasingly below-the-ankle disease pattern that can fail traditional approaches for endovascular intervention. Two techniques, the retrograde pedal access and the pedal-plantar loop technique, can be useful in these settings and in skilled hands can be used safely, with a high technical success rate. In patients with chronic limb-threatening ischemia who are not candidates for a single-segment saphenous vein bypass, the retrograde pedal access technique can be used not only in the setting of failed antegrade treatment, but also primarily when faced with a difficult groin or as an adjunct during a planned antegrade-retrograde intervention. The pedal plantar loop technique allows for retrograde access to tibial vessels without retrograde vessel puncture and additionally offers the ability to treat the pedal-plantar arch, which may have added benefit in wound healing. We describe the tips and tricks for these two techniques used in our limb salvage practice.

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Effect of Comorbidities on Outcomes of Infrapopliteal Angioplasty in Patients with Chronic Limb-Threatening Ischemia

OBJECTIVE

This subgroup analysis aimed to evaluate the effect of comorbidities on infrapopliteal angioplasty outcomes in patients with chronic limb-threatening ischemia (CLTI).

METHODS

This was an observational study evaluating eligible CLTI patients aged >18 years who underwent infrapopliteal angioplasty between April 2014 and May 2017 at a tertiary care center. Subgroup analyses were based on (1) baseline glycated hemoglobin (HbA1c ≤6.5% vs >6.5%), (2) presence/absence of chronic kidney disease (CKD), and (3) control of lipid parameters.

RESULTS

A total of 231 patients with 332 infrapopliteal vessels were treated. While diabetes was prevalent in all participants, hypertension, coronary artery disease, and CKD were reported in 76.6%, 46.3%, and 25.5% of patients at baseline, respectively. The overall technical success rate was 84.4%, and the patency rate at 6 months was 82.04%. Patency at 6 months, wound healing, in-line flow, and complete plantar arch formation were numerically higher in patients with HbA1c ≤6.5% versus >6.5%, but all comparisons were nonsignificant. According to multivariable analysis, the odds of wounds not healing was 2.38 times higher (odds ratio [OR] = 2.4, 95% confidence interval [CI]: 1.2 to 4.5) and developing plantar arch was 5.88 times higher (OR = 5.9, 95% CI: 1.3 to 25) among patients with CKD compared with patients without CKD.

CONCLUSIONS

The 6-month outcomes of infrapopliteal angioplasty may be better in patients with controlled versus uncontrolled glycemic levels. Control of lipid parameters may not have a significant influence on outcomes, especially in patients on statin therapy. The short-term outcomes may be similar in patients with and without CKD.

The role of atherectomy in BTK lesions. A systematic review

INTRODUCTION

To evaluate the current role of atherectomy techniques (ATH) in treatment of peripheral arterial disease (PAD) at below the knee (BTK) arteries.

EVIDENCE ACQUISITION

The PubMed and Embase were searched (last search on 11 September 2021) for studies reporting on the early and mid-term outcomes of ATH in BTK vessels. Analysis included the data from six studies, with a total of 1062 PAD patients treated with various ATH techniques. We compared them the ATH outcomes with the contemporaneous outcomes of plain balloon angioplasty alone or with bailout stenting. Early safety and efficacy were accessed with perioperative and 30-day technical success rate, which included the primary patency of the treated BTK arterial segment. Evaluation of clinical performance was based on target limb revascularization (TLR) and on major limb adverse events (MALEs) rates.

EVIDENCE SYNTHESIS

The current body of literature mainly includes retrospective observational studies, and the level of derived evidence is low. The mean perioperative and 30-day technical success rate was 87.3%. The mean reported TLR and MALEs rates at 12 months were 6.6% and 4.7% respectively. The relevant rates in studies reporting at 24 months were 24.3% and 31.7% while in studies reporting at 36 months the rates were 37.0% and 23.0% respectively.

CONCLUSIONS

Based in low-quality evidence, it seems that ATH in BTK vessels has a high safety, high efficacy profile and durable outcomes at 12 months. In the midterm, the clinical success of ATH is compromised by increased TLR and MALEs rates. Comparison of ATH with other endovascular techniques in BTK treatment of PAD shows a slight lead of ATH at 1-year and equivalent clinical performance in the mid-term. Overall, ATH has a significant and potentially predominant role in treatment of BTK vessels.

Physician experts in diabetes are natural team leaders for managing diabetic patients with foot complications. A position statement from the Italian diabetic foot study group

Diabetic foot syndrome (DFS) is a complex disease. The best outcomes are reported with the multi-disciplinary team (MDT) approach, where each member works collaboratively according to his/her expertise. However, which health provider should act as the team leader (TL) has not been determined. The TL should be familiar with the management of diabetes, related complications and comorbidities. He/she should be able to diagnose and manage foot infections, including prompt surgical treatment of local lesions, such as abscesses or phlegmons, in an emergent way in the first meeting with the patient. According to the Organization for Economic Co-operation and Development (OECD) reports, Italy is one of countries with a low amputation rate in diabetic patients. Many factors might have contributed to this result, including 1)the special attention directed to diabetes by the public health system, which has defined diabetes as a "protected disease", and accordingly, offers diabetic patients, at no charge, the best specialist care, including specific devices, and 2)the presence of a network of diabetic foot (DF) clinics managed by diabetologists with medical and surgical expertise. The health care providers all share a "patient centred model" of care, for which they use their internal medicine background and skills in podiatric surgery to manage acute or chronic needs in a timely manner. Therefore, according to Italian experiences, which are fully reported in this document, we believe that only a skilled diabetologist/endocrinologist should act as a TL. Courses and university master's degree programmes focused on DF should guarantee specific training for physicians to become a TL.

Revascularization of a specific angiosome for limb salvage: does the target artery matter?

Background

To compare clinical outcomes and technical success when direct versus indirect revascularization was achieved after endovascular technique for critical limb ischemia patients with isolated below-the-knee lesions. Fifty patients were included, 34 male and 16 female, their age from 49 to 77 years (mean 63 ±16). All patients were subjected to infra-genicular angioplasty and divided into direct 28 (31 limbs) and indirect groups 22 (24 limbs). Antegrade approach through ipsilateral CFA was used in 48 patients, while retrograde approach through tibiopedal access was used in 2 patients. Diagnostic angiography was done for all cases and duplex ultrasound was used for follow-up.

Results

One hundred thirty-two lesions were encountered, 46 in the ATA, 43 in PTA, 29 in peroneal artery, and 19 in dorsalis pedis artery. Transluminal approach was done in 47 limbs while subintimal cross was used in 8 limbs. After 1 year follow-up, AFS was 75% in the direct group and 67% in the indirect group. Freedom from MALE was 65% in the direct group and 55% in the indirect group. Freedom from MA was 86% in the direct group and 75% in the indirect group.

Conclusion

When there is a choice of target artery for revascularization, preference should be given to the artery directly feeding the wound’s angiosome.

[Reconstruction of lower limbs in old age-an interdisciplinary approach : Strategies for trauma surgery, vascular surgery and plastic surgery]

The treatment of complex injuries of the lower extremities in geriatric and/or multimorbid patients requires optimized preoperative and perioperative management as well as differentiated and interdisciplinary surgical approaches. Timely and definitive treatment should be strived for to avoid longer periods of immobilization. Temporary external stabilization of complex fractures, when necessary, should be followed by permanent loading stable internal osteosynthesis as soon as possible. Accompanying soft tissue defects are reconstructed after wound débridement using the full armamentarium of plastic and reconstructive surgical procedures, including microvascular free flap. In the context of perfusion compromised soft tissue situations, negative pressure wound therapy can provide sterile temporary defect coverage and aid in preconditioning poorly vascularized tissue before definitive reconstruction. A clarification of the vascular status in geriatric patients is paramount and relevant perfusion disorders should be treated either by intervention or open surgery before complex reconstructive interventions. Close interdisciplinary coordination of the various surgical procedures is imperative in order to guarantee an optimized stable reconstructive outcome with acceptable patient risk. Taking these principles into account, the reconstruction of complex trauma to the extremities can be carried out even in geriatric or multimorbid patients in specialized interdisciplinary surgical centers with excellent functional results.

Global Vascular Guidelines on the Management of Chronic Limb-Threatening Ischemia

GUIDELINE SUMMARY

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Combined percutaneous direct puncture of occluded artery - antegrade intervention for recanalization of below the knee arteries

PURPOSE

We aimed to assess the technical success of the combined percutaneous direct puncture of occluded artery - antegrade intervention technique, as well as the clinical effectiveness of treatment, on the basis of changes in the Rutherford classification.

METHODS

Between June 2015 and July 2018, 441 patients underwent endovascular recanalization due to lower limb peripheral arterial disease at our center. Of these, 18 patients (4%; 15 males, 3 females; mean age, 63.2 years) had failed antegrade recanalization and percutaneous retrograde access because of long segment occlusion, arterial rupture or dissection. Combined percutaneous direct puncture of occluded artery and antegrade approach was applied to these patients. Clinical follow-up examinations were performed at 1 month, 3 months, 6 months, and annually thereafter.

RESULTS

The mean follow-up period was 22.8±10.9 months. The mean procedure time was 93.6±28.2 min. Technical success was achieved in 14 patients (78%). Complete restoration of arterial flow in the punctured vessel could not be achieved in 4 patients (22%). Minor complications occurred in 4 of 18 procedures (22%). Amputation-free survival and limb salvage rates (83.3% and 100%, respectively) were the same for 12 and 24 months.

CONCLUSION

Technical success in lower limb peripheral arterial disease may be improved with the use of a combined percutaneous direct puncture of occluded artery - antegrade intervention, particularly for patients in whom other techniques are not a viable option.

Global vascular guidelines on the management of chronic limb-threatening ischemia

Chronic limb-threatening ischemia (CLTI) is associated with mortality, amputation, and impaired quality of life. These Global Vascular Guidelines (GVG) are focused on definition, evaluation, and management of CLTI with the goals of improving evidence-based care and highlighting critical research needs. The term CLTI is preferred over critical limb ischemia, as the latter implies threshold values of impaired perfusion rather than a continuum. CLTI is a clinical syndrome defined by the presence of peripheral artery disease (PAD) in combination with rest pain, gangrene, or a lower limb ulceration >2 weeks duration. Venous, traumatic, embolic, and nonatherosclerotic etiologies are excluded. All patients with suspected CLTI should be referred urgently to a vascular specialist. Accurately staging the severity of limb threat is fundamental, and the Society for Vascular Surgery Threatened Limb Classification system, based on grading of Wounds, Ischemia, and foot Infection (WIfI) is endorsed. Objective hemodynamic testing, including toe pressures as the preferred measure, is required to assess CLTI. Evidence-based revascularization (EBR) hinges on three independent axes: Patient risk, Limb severity, and ANatomic complexity (PLAN). Average-risk and high-risk patients are defined by estimated procedural and 2-year all-cause mortality. The GVG proposes a new Global Anatomic Staging System (GLASS), which involves defining a preferred target artery path (TAP) and then estimating limb-based patency (LBP), resulting in three stages of complexity for intervention. The optimal revascularization strategy is also influenced by the availability of autogenous vein for open bypass surgery. Recommendations for EBR are based on best available data, pending level 1 evidence from ongoing trials. Vein bypass may be preferred for average-risk patients with advanced limb threat and high complexity disease, while those with less complex anatomy, intermediate severity limb threat, or high patient risk may be favored for endovascular intervention. All patients with CLTI should be afforded best medical therapy including the use of antithrombotic, lipid-lowering, antihypertensive, and glycemic control agents, as well as counseling on smoking cessation, diet, exercise, and preventive foot care. Following EBR, long-term limb surveillance is advised. The effectiveness of nonrevascularization therapies (eg, spinal stimulation, pneumatic compression, prostanoids, and hyperbaric oxygen) has not been established. Regenerative medicine approaches (eg, cell, gene therapies) for CLTI should be restricted to rigorously conducted randomizsed clinical trials. The GVG promotes standardization of study designs and end points for clinical trials in CLTI. The importance of multidisciplinary teams and centers of excellence for amputation prevention is stressed as a key health system initiative.

Below-the-ankle Angioplasty: Current Evidence and Future Perspectives

Over 20 million adults in Europe suffer from peripheral arterial disease (PAD). The annual incidence of PAD is approximately 2.4%, while the annual incidence of critical limb ischaemia (CLI), the last and most severe stage of PAD, has been reported to be 0.4%. Endovascular angioplasty and/or stenting of infrapopliteal disease is, today, an established treatment for critical limb ischaemia. The main technical advantages of endovascular treatment over open bypass surgery include the possibility to revascularise more than one infrapopliteal vessels and, most importantly, to treat outflow pedal vessel disease or even reconstitute the pedal arch. Data of below-the-ankle angioplasty are beginning to sum up and the contribution of pedal arch angioplasty in limb salvage and wound healing are currently under investigation. In this review, currently available data and the future perspectives on below-the-ankle and pedal arch endovascular treatment will be presented.

Current evidence of drug-elution therapy for infrapopliteal arterial disease

New and sophisticated endovascular devices, such as drug-eluting stents (DES) and drug-coated balloons (DCB), provide targeted drug delivery to affected vessels. The invention of these devices has made it possible to address the reparative cascade of arterial wall injury following balloon angioplasty that results in restenosis. DESs were first used for the treatment of infrapopliteal lesions almost 20 years ago. More recently, however, DCB technology is being investigated to improve outcomes of endovascular below-the-knee arterial procedures, avoiding the need for a metallic scaffold. Today, level IA evidence supports the use of infrapopliteal DES for short to medium length lesions, although robust evidence that justifies the use of DCBs in this anatomical area is missing. This review summarizes and discusses all available data on infrapopliteal drug-elution devices and highlights the most promising future perspectives.

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.

Techniques for Infrapopliteal Arterial Bifurcation Stenting

BACKGROUND

Endovascular treatment of infrapopliteal peripheral arterial disease (PAD) is an established and effective treatment strategy for patients with symptomatic PAD. Increasingly, complex infrapopliteal lesions are treated with an endovascular first approach, especially in the setting of critical limb ischemia (CLI) for limb salvage, avoiding major amputations which impact on mobility and quality of life. However, many complex infrapopliteal lesions involving the bifurcation of the tibial arteries remain challenging to treat because of recoil or acute dissection after angioplasty and may require stenting using specialized techniques.

METHODS AND RESULTS

We illustrated techniques for infrapopliteal arterial bifurcation stenting using case-based examples. The techniques covered include the single-stent, culottes, kissing, crush, and T-stenting techniques, and each is considered based on individual strengths and limitations.

CONCLUSIONS

Infrapopliteal bifurcation stenting allows complex bifurcation lesions to be treated effectively when flow-limiting complications are encountered after angioplasty.

Dose-Decreasing Effect of the First Reversed Laser Beam Collimator for C-Arm Type Angiographic Equipment

This is a study on the dose-decreasing effect of the first reversed laser beam collimator (RLBC) for C-arm type angiographic equipment. A laser beam was located at the center of each plane at an oblique angle to the angiographic equipment detector. A field of view, which could be seen with the naked eye, was made by focusing the laser beam in the direction of the X-ray source. The height of the table was fixed at 75 cm and the iron balls were located within 2 mm of the top, bottom, left, and right edges of the output image. The time needed for location fixing, fluoroscopy, and measurement of dose area product (DAP) were compared by having 30 radiologists perform location fixing by looking at the fluoroscopic image while performing location fixing (no radiation) and while the RLBC was turned on. In the next test, the time needed for location fixing, fluoroscopy, and DAP were compared when varying the location of the iron balls from 2 to 10 mm from the edges of the output image. The results showed that the time needed for location fixing, the time needed for fluoroscopy, and DAP decreased, both in the first test and the second test. This study confirmed that the use of a RLBC for C-arm type angiographic equipment decreases both the time needed to perform the procedure and the radiation dose received. It is expected that continuous advancement of RLBC technology will contribute greatly to decreasing the dose of radiation needed and improving convenience during angiography.

Network meta-analysis of balloon angioplasty, nondrug metal stent, drug-eluting balloon, and drug-eluting stent for treatment of infrapopliteal artery occlusive disease

PURPOSE

We aimed to conduct a network meta-analysis of mixed treatments for the infrapopliteal artery occlusive disease.

METHODS

We searched randomized controlled trials (RCTs) regarding balloon angioplasty (BA), nondrug metal stent (NDMS), drug-eluting balloon (DEB), or drug-eluting stent (DES) in PubMed, Embase, CENTRAL, Ovid, Sinomed, and other relevant websites. We selected and assessed the trials that met the inclusion criteria and conducted a network meta-analysis using the ADDIS software.

RESULTS

We included 11 relevant trials. We analyzed data of 1322 patients with infrapopliteal artery occlusive disease, of which 351 were in the NDMS vs. DES trials, 231 in the NDMS vs. BA trials, 490 in the BA vs. DEB trials, 50 in the DEB vs. DES trials, and 200 in the BA vs. DES trials. The network meta-analysis indicated that with NDMS as the reference, DES had a better result with respect to restenosis (odds ratio [OR], 5.16; 95% credible interval [CI], 1.58-18.41; probability of the best treatment, 84%) and amputation (OR, 2.50; 95% CI, 0.81-7.11; probability of the best treatment, 61%) and DEB had a better result with respect to target lesion revascularization (TLR; OR, 3.74; 95% CI, 0.78-17.05; probability of the best treatment, 57%). Moreover, with BA as the reference, NDMS had a better result with respect to technical success (OR, 0.10; 95% CI, 0.00-1.15; probability of the best treatment, 86%).

CONCLUSION

Our meta-analysis revealed that DES is a better treatment with respect to short-term patency and limb salvage rate, NMDS may provide a better technical success, and DEB and DES are good choices for reducing revascularization.

The Excimer Laser: Science Fiction Fantasy or Practical Tool?

Nearly 20 years ago, in vitro experiments left no doubt about the fact that laser light can ablate atherosclerotic plaque. The initial enthusiastic results with the technology, particularly in coronary arteries, were followed by reports showing unacceptably high restenosis and complication rates. These poor results were due to the premature application of an underdeveloped technology, a lack of understanding of laser/tissue interaction, and the use of incorrect lasing techniques. Consequently, and without discrimination, all lasers were banned from the catheterization laboratories for nearly a decade. Technological enhancements of the excimer laser, combined with refined catheter lasing techniques, resulted in greater debulking of atherosclerotic material in long superficial femoral artery occlusions. These results triggered the application of the excimer laser technique as an atherectomy tool in more complex lesions below the knee. The multicenter Laser Atherectomy for Critical Ischemia study clearly demonstrated that the excimer laser technology resulted in limb salvage rates >90% in patients with critical limb ischemia (CLI). Furthermore, new clinical results indicate that the excimer laser is very effective in dissolving thrombotic obstructions, redirecting this technology to the coronary field.

The results of the excimer laser in CLI validate the role of the cool laser in treating complex peripheral vascular disease. The results suggest a larger indication for this technology and support a more aggressive use of these interventional techniques in the treatment of this large patient cohort. However, all lasers are not equally effective in debulking atherosclerotic material. Only the athermic process associated with the excimer laser produces a safe and effective endovascular ablation of obstructive atherosclerotic and/or thrombotic material. The appropriate and safe utilization of the equipment and lasing techniques, combined with correct indications and patient selection, will contribute to the successful application of laser-assisted atherectomy in complex peripheral and coronary artery obstructive disease. Unfortunately, little consistent scientific data has been generated to convince the interventional community of the usefulness of excimer laser ablation.

Comparison of Drug-Eluting Balloon and Standard Balloon Angioplasty for Infrapopliteal Arterial Diseases in Diabetic Patients

OBJECTIVE

To consider the clinical outcomes and restenosis rates of drug-eluting balloons (DEBs) and percutaneous transluminal angioplasty (PTA) in diabetic patients with infrapopliteal (IP) arterial disease.

MATERIALS AND METHODS

This retrospective, single-center study included 51 patients (37 males; mean age: 63.43 ± 9.81 years) with diabetes mellitus having IP arterial disease, from October 2012 to September 2014. Twenty-two patients were treated with PTA, and 29 patients were treated with DEBs. After intervention, the patients were evaluated in the first week and every 3 months, clinically and radiologically. Univariate and multivariate analyses were used to evaluate the clinical outcomes of diabetic patients with IP arterial disease who were treated with either DEBs or PTA.

RESULTS

There were no statistically significant differences between the groups in terms of age and gender, risk factors, characteristics of lesions, or the diameters or length of the balloons ( P > .05). Primary patency was higher in the DEB group than in the PTA group (97.8% vs 81.1%, P = .020) in the first 3 months. However, there was no statistically significant difference at 1-year follow-up (68.2% vs 48.5%, P = .131). At the 12-month follow-up, there was no difference in clinical improvement between the groups ( P = .193).

CONCLUSION

The findings of this study reveal that DEB is a safe alternative treatment method for IP arterial disease in diabetic patients.

Popliteal-to-Distal Bypass: Identifying Risk Factors Associated with Limb Loss and Graft Failure

Modern therapy, including endoluminal procedures and improved medical management, still yield less than desired results for tibial vessel occlusive disease. Despite the recent focus on these newer interventions, few modern series have evaluated the efficacy of popliteal-to-distal bypass procedures. The authors aimed to determine the efficacy of popliteal-distal bypass and to identify adverse prognostic factors for ultimate limb salvage. Eighty-seven patients (54 men; average age: 63 years) underwent 92 popliteal-distal bypasses. Duplex ultrasound was utilized to assess patency of all grafts. Data were analyzed by life-table analysis to determine patency rates at postoperative intervals. Median patient follow-up was 2.4 years. Major indications for bypass included chronic limb ischemia (86%) and disabling claudication (8%); 62% of the limbs were considered threatened, and 74% of the proximal anastomoses were above-knee. All procedures were technically successful. There were no perioperative (<30 days) deaths, and 86% of patients were alive at 5 years. Cumulative patency rates were 74% at 6 months, 70% at 2 years, and 63% at 5 years. Limb salvage rates closely paralleled patency rates. At 5 years, 62% of the affected limbs were intact; 72% of the limbs lost were associated with early (<180 days) bypass failures. Predictors of limb loss included early graft failure (84 days vs 1,288 days, p <0.0001), younger age (57 years vs 64 years, p = 0.039), history of previous ipsilateral vascular procedures (50% vs 21%, p = 0.03), heavy (>1 ppd) tobacco use (p = 0.001), and a thrombosed femoral-popliteal bypass at presentation (p = 0.002). When successful, popliteal-distal bypass is associated with excellent long-term patency and limb salvage rates. Early failures are often associated with limb loss. Heavy tobacco use, younger age, early graft failures, repeat revascularization, and presentation with a thrombosed femoral-popliteal graft are associated with limb loss.

Two-Year Results after Directional Atherectomy of Infrapopliteal Arteries with the SilverHawk Device

Purpose:

To report the 12- and 24-month results after directional atherectomy (DA) of below-the-knee (BTK) arterial lesions with the SilverHawk device.

Methods:

Forty-nine BTK lesions in 36 patients (58% men; mean age 70611 years) with peripheral occlusive disease of the lower limbs were treated with DA; 19 (53%) of the limbs were classified with Rutherford-Becker 4 or 5 ischemia. Target lesions were in the popliteal artery (n=6, 12%), tibioperoneal trunk (n=25, 51%), peroneal artery (n=10, 20%), anterior tibial artery (n=5, 10%), and posterior tibial artery (n=3, 6%). Nine (18%) lesions were located in a stent. Twelve lesions extended to 2 artery segments. The average degree of diameter stenosis was 89%±10% (range 70%–100%); there were 11 (22%) occlusions. The mean lesion length was 48±28 mm.

Results:

Sixteen (33%) lesions were treated after predilation; 33 (67%) lesions were treated with primary DA. All but 1 (2%) lesion could be treated with DA. In 19 (39%) lesions, additional balloon angioplasty was performed, and 2 (4%) lesions required stent implantation as a result of dissection. The mean stenosis diameter after DA was 12%±18% (range 0%–100%). After additional therapy, the mean stenosis diameter was 8%±9% (range 0%–100%). A residual stenosis ≤30% was achieved in 48 (98%) lesions. The mean ankle-brachial index significantly increased from 0.48±0.26 to 0.81±0.32 (p<0.05) before discharge and remained improved during follow-up. Primary and secondary patency rates were 67% and 91% after 1 year and 60% and 80% after 24 months. The 12-and 24-month cumulative event-free survival rates (primary patency) by Kaplan-Meier analysis were 58%±8% and 46%±9%; at the same time intervals, the cumulative survival rates (secondary patency) were 88%±6% and 73%±9%, respectively.

Conclusion:

BTK lesions can be treated successfully and safely with DA. Midterm clinical results are encouraging.

Outcomes of Endovascular Therapy With the Controlled Antegrade Retrograde Subintimal Tracking (CART) or Reverse CART Technique for Long Infrainguinal Occlusions

Purpose: To compare the safety, efficacy, and clinical outcomes associated with the controlled antegrade retrograde subintimal tracking (CART) or reverse CART (r-CART) technique to the conventional retrograde approach in the treatment of patients with long infrainguinal occlusions. Methods: From May 2008 to April 2014, 121 patients failed antegrade recanalization and underwent a retrograde approach to recanalize long infrainguinal occlusions. Patients who underwent successful endovascular therapy (EVT) by the conventional retrograde approach (CRA group) were compared to patients who had successful EVT using the CART/r-CART technique (CART group) after failure of a bidirectional approach. The efficacy, safety, vessel patency, and other clinical outcomes were compared between the groups. Results: Fifty-eight patients (mean age 71.6±12.2 years; 32 men) underwent successful EVT (47.9%, 58/121) using the conventional retrograde approach (CRA group), while 44 patients (mean age 70.8±11.1 years; 31 men) among the 50 patients who underwent the CART/r-CART technique were successfully treated (88.0%, 44/50). Both groups had similar average occlusion lengths and gained 100% immediate hemodynamic success after EVT. There was no significant difference between the groups regarding procedure-related complications. During follow-up, 28 patients died (p=0.380), but there were no differences in the rates of major (p=0.279) or minor amputation (p=0.417) between the groups. There was no difference in the 2-year primary patency (31% vs 24%, p=0.686), assisted primary patency (66% vs 76%, p=0.251), target vessel revascularization (65% vs 54%, p=0.845), or sustained clinical success (52% vs 46%, p=0.995) rates between the CRA and CART groups, respectively. Conclusion: Based on acceptable safety, efficacy, and follow-up results in this study, the CART/r-CART technique can salvage patients with long peripheral occlusions after failure of the conventional antegrade or retrograde approach.

Peripheral Arterial Disease in Patients with Type 2 Diabetes Mellitus

Peripheral arterial disease (PAD) in patients with type 2 diabetes mellitus (T2DM) exhibits broad clinical characteristics and various consequences and is known as one of the major macrovascular complications of T2DM. Atherosclerosis is recognized as the most direct and important cause of PAD, but acute or chronic limb ischemia may be the result of various risk factors. In light of the increasing number of patients who undergo peripheral vascular procedures, the number of subjects who are exposed to the risks for PAD and related complications is increasing. In this review, we will discuss the clinical and epidemiological characteristics of PAD, as well as the clinical significance of PAD in T2DM subjects.

Local delivery of paclitaxel in the treatment of peripheral arterial disease

BACKGROUND

Despite advancements from balloon angioplasty to drug-eluting stents, primary patency rates after endovascular revascularization of peripheral artery disease have remained inferior compared to surgery. Endovascular revascularization has been limited by restenosis and mechanical stent failure. Thus, there is increased research into other nonstent-based local drug delivery modalities, which can provide an active drug to inhibit restenosis focally and avoid the risk of systemic adverse effects.

METHODS

This review will summarize the unique properties of paclitaxel and studies on paclitaxel local delivery for the treatment of peripheral artery disease. A MEDLINE search for relevant peer-reviewed scientific literature published in English was conducted. Search terms included but were not limited to paclitaxel pharmacodynamics, paclitaxel local drug delivery, and drug eluting balloons, with a focus on the use of paclitaxel in the context of coronary and peripheral vascular disease.

RESULTS

The primary search produced 182 results of which 51 papers were relevant. Of the 51 relevant papers, 27 were original research papers and 24 were either review papers, commentary or opinion papers.

CONCLUSIONS

Paclitaxel has several chemical properties, which make it ideal for local drug delivery including its hydrophobicity, ability to concentrate into the arterial intima layer and prolonged effect on cells even after brief exposure periods. Local delivery of paclitaxel via injection catheters, balloon catheters and coated balloons has shown encouraging results in terms of efficacy and safety in small-scale animal and clinical studies. Additional preclinical and clinical studies are needed to determine the long-term efficacy and safety of these treatments in humans.

Infrapopliteal arterial recanalization: A true advance for limb salvage in diabetics

The world is facing an epidemic of diabetes; consequently in the next years, critical limb ischemia (CLI) due to diabetic arterial disease, characterized by multiple and long occlusions of below-the-knee (BTK) vessels, will become a major issue for vascular operators. Revascularization is a key therapy in these patients as restoring adequate blood supply to the wound is essential for healing, thus avoiding major amputations. Endoluminal therapy for BTK arteries is now a key part of the vascular specialist armamentarium. Tibial artery endovascular approaches have been shown to achieve high limb salvage rates with low morbidity and mortality and endovascular interventions one should now consider to be the first line treatment in the majority of CLI patients, especially in those with associated medical comorbidities. To do so, the vascular specialist requires detailed knowledge of the BTK endovascular techniques and devices. The first step decision in tibial endovascular therapy is access. In this context, the anterograde ipsilateral approach is generally preferred. The next critical decision is the choice of the vessel(s) to be approached in order to achieve successful limb salvage. Obtaining pulsatile flow to the correct portion of the foot is the paramount for ulcer healing. As such, a good understanding of the current angiosome model should enhance clinical results. The devices used should be carefully selected and optimal choice of guide wire is also extremely important and should be based on the characteristics of the lesion (location, length, and stenosis/occlusion) together with the characteristics of the guide wire itself (tip load, stiffness, hydrophilic/hydrophobic coating, flexibility, torque transmission, trackability, and pushability). Passing through chronic total occlusions can be quite challenging. The vascular interventional radiologist needs therefore to master the techniques that have been recently described: anterograde approaches, including the drilling technique, the penetrating technique, the subintimal technique and the parallel technique; subintimal arterial flossing with anterograde-retrograde procedures (Safari); the pedal-plantar loop technique and revascularization through collateral fibular artery vessels.

The Importance of Patency in Patients with Critical Limb Ischemia Undergoing Endovascular Revascularization for Infrapopliteal Arterial Disease

Critical limb ischemia (CLI) represents the most severe form of peripheral arterial disease (PAD) and frequently occurs in medically frail patients. CLI patients frequently exhibit multi-segmental PAD commonly including the tibial arterial segment. Endovascular therapy has been established as first-line revascularization strategy for most CLI patients. Restenosis was reported to occur in up to more than two-thirds of CLI patients undergoing angioplasty of complex tibial arterial obstructions. Nevertheless, favorable clinical outcomes were observed for infrapopliteal angioplasty when compared with bypass surgery, despite higher patency rates for the latter. Based on these observations, infrapopliteal patency was considered to be only of secondary importance upon clinical outcomes in CLI patients. In contrast to these earlier observations, however, recent findings from two randomized clinical trials indicate that infrapopliteal patency does impact on clinical outcomes in CLI patients. The purpose of the present manuscript is to provide a critical reappraisal of the present literature on the clinical importance of tibial arterial patency in CLI patients undergoing endovascular revascularization and to discuss utility and limitations of currently available anti-restenosis technologies.

Contemporary treatment for critical ischemia: the evidence for interventional radiology or surgery

This article is a review of the evidence regarding the management of patients with critical limb ischemia. The aim of the study is to discuss the definition, incidence, and clinical importance of critical limb ischemia, as well as the aims of treatment in terms of quality of life and limb salvage. Endovascular and surgical treatments should not be viewed as competing therapies. In fact, these are complementary techniques each with strengths and weaknesses. The authors will propose a strategy based on the available evidence for deciding the optimal approach to management of patients with critical limb ischemia.

Treating calf and pedal vessel disease: the extremes of intervention

Recent developments in catheter, balloon, and guidewire technology have increased the scope for endovascular treatments in the management of complex and challenging disease in the calf and foot. The antegrade femoral approach remains the starting point for most interventions, but there is a growing role for procedures performed from unconventional access such as the pedal arteries. This article reviews the indications for intervention, atypical access, and the choice of equipment for these extreme interventions.

Endovascular therapy is effective treatment for focal stenoses in failing infrapopliteal vein grafts

BACKGROUND

To evaluate the efficacy of endovascular therapy for maintaining patency and preserving limbs among patients with failing infrapopliteal bypass grafts.

METHODS

We gathered data from a registry of catheter-based procedures for peripheral artery disease. Of 1554 arteriograms performed from 2006 to 2012, 30 patients had interventions for failing bypass vein grafts to infrapopliteal target vessels. The first intervention for each patient was used in this analysis. Duplex ultrasonography was used within 30 days after intervention and subsequently at 3- to 6-month intervals for graft surveillance.

RESULTS

Interventions were performed for duplex ultrasonography surveillance findings in 21 patients and for symptoms of persistent or recurrent critical limb ischemia in 9 patients. Procedural techniques included cutting balloon angioplasty (83%), conventional balloon angioplasty (7%), and stent placement (10%). Procedural success was achieved in all cases. There were no procedure-related complications, amputations, or deaths within 30 days. By Kaplan-Meier analysis, 37% of the patients were free from graft restenosis at 12 months and 31% were at 24 months. Receiver-operating characteristic analysis indicated that a lesion length of 1.75 cm best predicted freedom from restenosis (C statistic: 0.74). Residual stenosis (P = 0.03), patency without reintervention (P = 0.01), and assisted patency with secondary intervention (P = 0.02) rates were superior for short lesions compared with long lesions. The cohort had acceptable rates of adverse clinical outcomes, with 96% of patients free from amputation at both 12 and 24 months; clinical outcomes were also better in patients with short lesions.

CONCLUSIONS

In this single-center experience with endovascular therapies to treat failing infrapopliteal bypass grafts, rates of limb preservation were high, but the majority of patients developed graft restenosis within 12 months. Grafts with longer stenoses fared poorly by comparison. These data suggest that endovascular interventions to restore or prolong graft patency may be associated with maintained graft patency and that close follow-up with vascular laboratory surveillance is essential.

Endovascular recanalization of infrapopliteal occlusions in patients with critical limb ischemia

BACKGROUND

Endovascular therapies are increasingly used for treatment of critical limb ischemia (CLI). Infrapopliteal (IP) occlusions are common in CLI, and successful limb salvage may require restoration of arterial flow in the distribution of a chronically occluded vessel. We sought to describe the procedural characteristics and outcomes of patients with IP occlusions who underwent endovascular intervention for treatment of CLI.

METHODS

All patients with IP interventions for treatment of CLI from 2006 to 2012 were included. Angiographic and procedural data were compared between patients who underwent intervention for IP occlusions vs IP stenosis. Restenosis was determined by Doppler ultrasound imaging. Limb salvage was the primary end point of the study. Additional end points included primary patency, primary assisted patency, secondary patency, occlusion crossing success, procedural success, and amputation-free survival.

RESULTS

A total of 187 patients with CLI underwent interventions for 356 IP lesions, and 77 patients (41%) had interventions for an IP occlusion. Patients with an intervention for IP occlusion were more likely to have zero to one vessel runoff (83% vs 56%; P < .001) compared with interventions for stenosis. Compared with IP stenoses, IP occlusions were longer (118 ± 86 vs 73 ± 67 mm; P < .001) and had a smaller vessel diameter (2.5 ± 0.8 vs 2.7 ± 0.5 mm; P = .02). Wire crossing was achieved in 83% of IP occlusions, and the overall procedural success for IP occlusions was 79%. The overall 1-year limb salvage rate was 84%. Limb salvage was highest in the stenosis group, slightly lower in the successful occlusion group, and lowest in the failed occlusion group (92% vs 75% vs 58%, respectively; P = .02). Unsuccessfully treated IP occlusions were associated with a significantly higher likelihood of major amputation (hazard ratio, 5.79; 95% confidence interval, 1.89-17.7) and major amputation or death (hazard ratio, 2.69; 95% confidence interval, 1.09-6.63).

CONCLUSIONS

Successful endovascular recanalization of IP occlusions can be achieved with guidewire and support catheter techniques in most patients. In patients selected for an endovascular-first approach for IP occlusions in CLI, this strategy can be successfully implemented with favorable rates of limb salvage.

Meta-analysis of outcomes of endovascular treatment of infrapopliteal occlusive disease with drug-eluting stents

PURPOSE

To review emerging evidence regarding the use of bare metal (BMS) vs. drug-eluting stents (DES) in the treatment of infrapopliteal occlusive disease.

METHODS

A systematic review of the literature was undertaken to identify all studies comparing stent treatments of infragenicular vessels in patients with chronic lower limb ischemia. Validated methods to assess the methodological quality of the included studies were applied. Outcome data were pooled, and combined overall effect sizes were calculated using fixed or random effects models. The search identified 4 randomized clinical trials and 2 observational studies reporting on 544 patients (287 treated with DES and 257 treated with BMS). Data are presented as the odds ratio (OR) with 95% confidence interval (CI) and the number-needed-to-treat (NNT).

RESULTS

Primary patency, freedom from target lesion revascularization, and clinical improvement at 1 year were significantly higher in the DES recipients compared to patients treated with BMS (OR 4.511, 95% CI 2.897 to 7.024, p<0.001, NNT 3.5; OR 3.238, 95% CI 2.019 to 5.192, p<0.001, NNT 6.0; and OR 1.792, 95% CI 1.039 to 3.090, p=0.036, NNT 7.3, respectively). No significant differences in limb salvage and overall survival at 1 year were identified between the groups (OR 2.008, 95% CI 0.722 to 5.585, p=0.181; OR 1.262, 95% CI 0.605 to 2.634, p=0.535, respectively). Sensitivity analyses investigating the potential effects of study design and type of DES on the combined outcome estimates validated the results.

CONCLUSION

Our analysis has demonstrated superior short-term results with DES compared with BMS, expressed by increased patency and freedom from target lesion revascularization. The influence of this finding on clinical surrogate endpoints, such as limb salvage, remains unknown.

Infrapopliteal lesion morphology in patients with critical limb ischemia: implications for the development of anti-restenosis technologies

PURPOSE

To angiographically evaluate infrapopliteal arterial lesion morphology in a consecutive series of patients presenting with critical limb ischemia (CLI) and undergoing infrapopliteal angioplasty.

METHODS

A prospective analysis was undertaken of a consecutive series of CLI patients undergoing endovascular therapy in a tertiary referral center in the year 2011. Morphological assessment of baseline angiograms obtained prior to revascularization included lesion length, assessment of calcification using a semi-quantitative scoring system, and reference vessel diameter (RVD) measurement. Delta RVDs were assessed subtracting distal RVDs from proximal RVDs. A total of 197 infrapopliteal lesions in 105 CLI patients (n=106 limbs) were assessed. Of these, 136 lesions were treated by endovascular means.

RESULTS

The average length of treated lesions was 87.1±43.8 mm in stenoses and 124.0±78.3 mm in chronic occlusions (p<0.001). Mean RVD proximal to the lesions was 1.88 mm whereas it was 1.66 mm distal to the lesions (p≤0.03). Mean arterial calcification was 1.15.

CONCLUSION

This prospective angiographic series underlines the complex nature and extensive longitudinal involvement of infrapopliteal lesions in CLI patients. These findings should be taken into consideration for anti-restenosis concepts in this challenging subgroup of peripheral artery disease patients.