Duplex-guided endovascular treatment for occlusive and stenotic lesions of the femoral-popliteal arterial segment: A comparative study in the first 253 cases

Feasibility of Percutaneous Ultrasound Guided Intervention with Direct Access in Failing Infrainguinal Vein Bypass Grafts

BACKGROUND

Patients with infrainguinal venous bypass grafts are at risk of graft stenosis leading to thrombosis and failure of the graft conduit. When primary assisted reintervention is needed, a common first choice of treatment is percutaneous angioplasty using fluoroscopy and digital subtraction angiography (DSA). We investigated whether percutaneous ultrasound-guided intervention (PUSGI) is feasible for such endovascular reinterventions.

METHODS

In this retrospective observational study (feasibility study), we included patients with ultrasound evidence of significant stenosis in below-the-knee vein grafts in the lower extremities. Inclusion period was 18 months. Reinterventions were disrupted by performing PUSGI in between traditional DSA. Perioperative success was defined as no sign of residual stenosis, stenosis at the access point in the vein, or need for further fluoroscopy guided intervention. Patient follow-up was conducted 6 weeks after the intervention. Patency of the procedure was defined as no disease recurrence or signs of ultrasonographic restenosis at follow-up.

RESULTS

PUSGI was performed in 17 patients referred for reintervention with imminent failing grafts (12 men, 5 women, age range 52-82 years). PUSGI alone was performed successfully in 10 out of 17 patients (59%). The remaining 7 patients underwent successful revascularization with PUSGI in combination with DSA-guided angioplasty. Periprocedural complications occurred in 4 patients. Two of 17 patients had occluded grafts at 6 weeks of follow-up. No PUSGI access site stenoses in grafts were observed.

CONCLUSIONS

Percutaneous ultrasound-guided reintervention in peripheral vein bypass disease is feasible for selected patients. The study provides insight to qualitative criteria of eligibility for PUSGI in such reinterventions with direct conduit access.

Feasibility and impact of extra-vascular ultrasound-guided endovascular treatment for infrapopliteal artery occlusive disease

PURPOSE

This study aimed to examine the feasibility and impact of extra-vascular ultrasound (EVUS)-guided intervention for infrapopliteal (IP) artery occlusive disease.

MATERIALS AND METHODS

A retrospective analysis was performed using data collected from patients who underwent endovascular treatment (EVT) for IP artery occlusive disease between January 2018 and December 2020 at our institution. A total of 63 consecutive de novoocclusive lesions were compared according to the recanalization method utilized. Propensity score matching analysis was performed to compare the clinical outcomes of the methods utilized. The prognostic value was analyzed based on the technical success rate, distal puncture rate, radiation exposure, amount of contrast media, postprocedural skin perfusion pressure (SPP), and procedural complication rate.

RESULTS

Eighteen matched pairs of patients were analyzed using propensity score-matched analysis. Radiation exposure was significantly lower in the EVUS-guided group than in the angio-guided group, with 135 and 287 mGy (p = 0.04) exposure on average, respectively. There were no significant differences between the two groups in terms of technical success rate, distal puncture rate, the amount of contrast media, postprocedural SPP, and procedural complication rate.

CONCLUSION

EVUS-guided EVT for IP occlusive disease achieved a feasible technical success rate and significantly reduced radiation exposure.

Comparison of ultrasound-guided versus angiography-guided endovascular treatment for femoropopliteal artery occlusive disease

PURPOSE

This study aimed to compare the efficacy of ultrasound-guided and angiography-guided intraluminal approach for femoropopliteal (FP) artery occlusive disease.

METHODS

A retrospective analysis was performed using the data collected regarding patients that underwent endovascular treatment (EVT) for FP artery occlusive disease between January 2010 and April 2018 at two centers. A total of 221 consecutive de novo lesions were analyzed according to the method of recanalization. Propensity score-matched analysis was performed to compare the clinical outcomes of recanalization methods for FP occlusive lesions. The prognostic value was analyzed based on the number of guidewires, wire cross time, distal puncture rate, radiation exposure, the amount of contrast media, primary patency, and clinically driven-target lesion revascularization (CD-TLR) at 1 year.

RESULTS

A total of 44 matched pairs of patients were analyzed after propensity score-matched analysis. The number of guidewires, distal puncture rate, wire passage time, radiation exposure, and the amount of contrast media were significantly lower in the ultrasound-guide group, with 3.4 vs. 4.7, 9.1% vs. 54.5%, 47 min vs. 83 min, 207 mGy vs. 821 mGy, 66 ml vs. 109 ml, respectively (p < .01), but there were no significant differences between the two groups in terms of primary patency and CD-TLR.

CONCLUSIONS

The ultrasound-guided EVT for FP occlusive disease significantly reduced the number of guidewires, wire cross time, the rate of distal puncture, radiation exposure, and the amount of contrast media used.

Robotized ultrasound imaging of the peripheral arteries – a phantom study

The first choice in diagnostic imaging for patients suffering from peripheral arterial disease (PAD) is 2D ultrasound (US). However, for a proper imaging process, a skilled and experienced sonographer is required. Additionally, it is a highly user-dependent operation. A robotized US system that autonomously scans the peripheral arteries has the potential to overcome these limitations. In this work, we extend a previously proposed system by a hierarchical image analysis pipeline based on convolutional neural networks (CNNs) in order to control the robot. The system was evaluated by checking its feasibility to keep the vessel lumen of a leg phantom within the US image while scanning along the artery. In 100% of the images acquired during the scan process the whole vessel lumen was visible. While defining an insensitivity margin of 2.74 mm, the mean absolute distance between vessel center and the horizontal image center line was 2.47 mm and 3.90 mm for an easy and complex scenario, respectively. In conclusion, this system presents the basis for fully automatized peripheral artery imaging in humans using a radiation-free approach.

Roboterbasierte Ultraschallsteuerung

Hintergrund

Die periphere endovaskuläre Chirurgie ist nach wie vor durch die Anwendung von Röntgenstrahlen und Röntgenkontrastmittel für die intraprozedurale Navigation der Instrumentarien ein Verfahren mit potenziellen Risiken und Nebenwirkungen.

Projektziel

Ziel des RoGUS-PAD (Robotic-Guided Ultrasound System for Peripheral Arterial Disease)-Projektes ist die Entwicklung eines roboterbasierten ultraschallgesteuerten Assistenzsystems für periphere endovaskuläre Interventionen zur Verringerung und ggf. Vermeidung von Röntgenstrahlung und Röntgenkontrastmittel sowie Verbesserung der Echtzeitvisualisierung.

Material und Methoden

Für die Bildgebung wurde ein 2‑D-Ultraschall-Lineartastkopf (L12‑3, Philips Healthcare, Best, Niederlande) am Endeffektor eines Roboterarms (LBR iiwa 7 R800, KUKA, Augsburg, Deutschland) montiert. Die ersten Versuche wurden an einem eigens für dieses Projekt entwickelten ultraschallfähigen Phantom durchgeführt. Die Bildverarbeitung und Robotersteuerung erfolgten durch ein speziell entwickeltes Programm in C++.

Ergebnisse

Zur Testung der technischen Umsetzbarkeit des Projektes konnten wir einen semiautomatischen 2‑D-Ultraschallscan einer peripheren Arterie am Phantom durchführen. In 27 von 30 Durchläufen zeigte sich ein erfolgreicher Scanvorgang.

Schlussfolgerung

Unsere ersten Ergebnisse bestätigten, dass die Entwicklung eines roboterbasierten Assistenzsystems für ultraschallgesteuerte periphere endovaskuläre Interventionen technisch umsetzbar ist. Dies stützt unsere Ambitionen einer Translation des Systems in die tägliche klinische Praxis.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Endovascular Treatment of Long Superficial Femoral Artery-Chronic Total Occlusions Using the Gogo Catheter With IVUS Via a Popliteal Puncture Method Is Effective, Safe, and Useful

OBJECTIVES

We aimed to investigate the usefulness of inserting a 6Fr sheath guided by duplex ultrasonography via a popliteal artery puncture. We also aimed to demonstrate endoluminal tracking using a retrograde approach using the Gogo catheter with intravascular ultrasound (IVUS).

BACKGROUND

The bidirectional approach is useful for increasing the success rate of the procedure for long superficial femoral artery-chronic total occlusions (SFA-CTOs). However, this procedure becomes somewhat complicated. Since the proximal blood vessel diameter is clearly larger than the distal end of the CTO and the body surface duplex guide can also be used in the proximal part, it is easier to introduce a retrograde guidewire (GW) into the proximal end.

METHODS

We performed endovascular treatment for long SFA-CTOs with a Gogo catheter + IVUS guide in 31 consecutive cases (male 20/female 11; mean age, 75.6 ± 7.6) from May 2017 to November 2018. We advanced the IVUS until the true lumen could be confirmed and advanced the Gogo catheter toward the IVUS for reinforcement. We attempted to approach the long CTO by repeating this procedure. We named this procedure the GIP method (GIP: Gogo catheter with IVUS via a popliteal puncture). Hemostasis of the popliteal artery was achieved using a commercially available compression hemostatic kit (Tometa-kun, XEMEX, Japan).

RESULTS

Successful revascularization was achieved in all cases (in 2 cases, a femoral artery puncture was added, and a bidirectional approach was used, and in 1 case, a CROSSER system was used). On average, the fluoroscopy time was 42.2 ± 30.4 minutes, radiation dose 93.7 ± 78.7 mGy, and amount of contrast medium used 15.0 ± 9.6 mL. The procedure time was defined as from the start of the popliteal artery puncture to the time the GW passed through the CTO lesion, including the posture transformation time from prone to the supine position. The procedure time was 42.1 ± 40.2 minutes. There were no major adverse events or other major complications, such as a distal embolism, rupture of the CTO lesion, arteriovenous fistula, or major hematoma requiring a transfusion or surgical treatment. Only 2 small hematomas occurred at the popliteal artery puncture site. The patients were treated conservatively and were discharged as usual.

CONCLUSIONS

Endovascular treatment of long SFA-CTOs via the popliteal approach was effective and safe. Using the GIP method to address long SFA-CTOs is recommended.

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.

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.

Arterial Compression of Left Iliac Veins: Five-Year Patency Rates of Endovascular Treatment

Endovascular angioplasty and stenting have become a treatment of choice for severely symptomatic left iliac veins under external, arterial compression. Patency rates of stented iliac veins based on ultrasonographic (US) findings were estimated. Retrospective analyses of gender, age, deep venous thrombosis (DVT) prior to stenting, stent location at common and/or external iliac veins, and patency rates from 1 month to 5 years were performed. Patients treated were mostly women (72 of 79, 91%), aged 51 ± 16 (25-89) years. Patency rates were 96% at 1 month, 89% at 1 year, and 85% at 3 to 5 years, best for common iliac, 95%, than for external iliac vein stents, subgroup with prior DVT, with secondary patency rates of 75%. US demonstrated acceptable patency rates for iliac vein stenting showing good performance for common iliac vein stents but a decreased performance with stent extending to the external iliac vein or stents placed in patients with prior iliac DVT.

Transvenous Intravascular Ultrasound-Guided Endovascular Treatment for Chronic Total Occlusion of the Infrainguinal Arteries

PURPOSE

To investigate the 1-year outcomes of transvenous intravascular ultrasound (IVUS)-guided endovascular therapy (EVT) for chronic total occlusion (CTO) of the lower extremity arteries.

METHODS

Transvenous IVUS-guided EVT was performed in 44 patients (50 limbs) with CTO of the femoropopliteal arteries or tibioperoneal trunk. Treatment involved crossing a guidewire through the CTO under the guidance of both fluoroscopic and IVUS imaging, along with insertion of the IVUS catheter into a vein parallel to the target artery. Primary success rate, complications, and target lesion revascularization (TLR) at 12-month follow-up were investigated.

RESULTS

Successful recanalization, defined as grade 3 flow (Thrombolysis in Myocardial Infarction score) and no flow-limiting dissection, was observed in 48 (96%) limbs. Two limbs with failed recanalization had a very long CTO lesion from the superficial femoral artery to below the knee. A bidirectional approach was selected in 11 (22%) limbs. Complications at the access site occurred in only 2 patients. The rate of freedom from TLR at 12 months was 77.9% (95% confidence interval 61.4 to 87.9).

CONCLUSION

Transvenous IVUS-guided EVT is safe and can provide optimal short-term results for EVT of CTO in the infrainguinal arteries. IVUS-guided EVT may be one of the most effective treatment strategies for CTO of the femoropopliteal arteries or tibioperoneal trunk.

Society for Vascular Surgery practice guidelines for atherosclerotic occlusive disease of the lower extremities: management of asymptomatic disease and claudication

Peripheral arterial disease (PAD) continues to grow in global prevalence and consumes an increasing amount of resources in the United States health care system. Overall rates of intervention for PAD have been rising steadily in recent years. Changing demographics, evolution of technologies, and an expanding database of outcomes studies are primary forces influencing clinical decision making in PAD. The management of PAD is multidisciplinary, involving primary care physicians and vascular specialists with varying expertise in diagnostic and treatment modalities. PAD represents a broad spectrum of disease from asymptomatic through severe limb ischemia. The Society for Vascular Surgery Lower Extremity Practice Guidelines committee reviewed the evidence supporting clinical care in the treatment of asymptomatic PAD and intermittent claudication (IC). The committee made specific practice recommendations using the GRADE (Grades of Recommendation Assessment, Development and Evaluation) system. There are limited Level I data available for many of the critical questions in the field, demonstrating the urgent need for comparative effectiveness research in PAD. Emphasis is placed on risk factor modification, medical therapies, and broader use of exercise programs to improve cardiovascular health and functional performance. Screening for PAD appears of unproven benefit at present. Revascularization for IC is an appropriate therapy for selected patients with disabling symptoms, after a careful risk-benefit analysis. Treatment should be individualized based on comorbid conditions, degree of functional impairment, and anatomic factors. Invasive treatments for IC should provide predictable functional improvements with reasonable durability. A minimum threshold of a >50% likelihood of sustained efficacy for at least 2 years is suggested as a benchmark. Anatomic patency (freedom from restenosis) is considered a prerequisite for sustained efficacy of revascularization in IC. Endovascular approaches are favored for most candidates with aortoiliac disease and for selected patients with femoropopliteal disease in whom anatomic durability is expected to meet this minimum threshold. Conversely, caution is warranted in the use of interventions for IC in anatomic settings where durability is limited (extensive calcification, small-caliber arteries, diffuse infrainguinal disease, poor runoff). Surgical bypass may be a preferred strategy in good-risk patients with these disease patterns or in those with prior endovascular failures. Common femoral artery disease should be treated surgically, and saphenous vein is the preferred conduit for infrainguinal bypass grafting. Patients who undergo invasive treatments for IC should be monitored regularly in a surveillance program to record subjective improvements, assess risk factors, optimize compliance with cardioprotective medications, and monitor hemodynamic and patency status.

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.

Use of duplex guided stent graft placement to prevent bleeding from previously thrombosed pseudo-aneurysms during thrombolytic therapy for acute popliteal artery occlusion

We present a 68-year-old female who developed multiple pseudo-aneurysms (PSAs) following cardiac catheterization via the right groin. During subsequent thrombin injection of PSAs, the patient developed acute occlusion of the popliteal artery. A covered stent was placed to obliterate the PSAs and allow for successful endovascular treatment of the occlusion without hemorrhage from the previous arteriotomy sites. This report demonstrates a safe and successful method to treating high surgical risk patients with recent PSA's and a necessity for thrombolysis.

The use of gadolinium for arterial interventions

BACKGROUND

Gadolinium (Gd) has been traditionally used as a non-nephrotoxic alternative to iodinated contrast for digital subtraction angiography (DSA) in patients with chronic renal insufficiency. However, its use has been questioned on the basis of reports of nephrotoxicity and its recent association with nephrogenic systemic fibrosis (NSF), a potentially lethal complication. Recently available data are conflicting with respect to the true safety profile of intra-arterial Gd. The purpose of this study was to examine the risk of contrast nephropathy and NSF after Gd exposure in a large population of azotemic patients undergoing DSA.

METHODS

A comprehensive database encompassing data on all patients who underwent DSA between June 2003 and December 2007 at the New York Presbyterian Hospital was retrospectively reviewed. Patients receiving Gd either alone or in combination with iodinated contrast during DSA were identified and further analyzed. Acute renal failure (ARF) was defined as an elevation in serum creatinine (Cr) by >0.5 mg/dL within 48 hours of exposure. Clinical follow-up was conducted through chart reviewing as well as telephonic interviews with patients and their primary care physicians.

RESULTS

A total of 153 patients underwent 179 exposures to Gd either alone (33%) or in combination (67%) with iodinated contrast. Mean follow-up duration was 27.1 months. The mean Cr level was 1.94 ± 0.78 mg/dL and 1.96 ± 1.1 mg/dL before and after DSA, respectively. There were 20 (11.2%) instances of ARF. The mean Cr level before DSA was higher in patients who developed ARF versus those in the non-ARF group (2.7 ± 1.1 mg/dL vs. 1.9 ± 0.7 mg/dL, p = 0.004). In the ARF group, 12 patients had a return to baseline renal function, four experienced irreversible renal deterioration, and four needed dialysis (4.5% incidence of irreversible renal failure). There were 19 deaths at the time of this study (12.4%). The highest risk for the development of ARF after Gd exposure occurred in patients with Cr levels of >3.0 mg/dL before DSA and in those receiving >0.4 mmol/kg of Gd. For patients who received iodinated contrast in combination with Gd, there was a trend toward a higher risk for developing ARF as compared with those receiving only Gd. Finally, there were no instances of NSF identified in any of the patients who received intra-arterial Gd.

CONCLUSIONS

Although Gd has the potential to cause kidney injury similar to iodinated contrast, the risk of irreversible renal failure and the requirement for dialysis is low. Life- or limb-threatening interventions should not be avoided in this patient cohort because of preexisting elevations in Cr. These data should help guide the use of Gd in patients with chronic renal insufficiency.

Early duplex scanning after infrainguinal endovascular therapy

OBJECTIVES

Duplex ultrasound scanning (DUS) has benefit for intraoperative and subsequent evaluation of surgical bypasses in the lower extremities. The utility of DUS after endovascular revascularizations is not established. This study was performed to evaluate whether DUS findings after infrainguinal endovascular interventions for critical limb ischemia (CLI) were predictive of need for reintervention or amputation.

METHODS

To identify the study cohort, peripheral interventions for CLI (Rutherford grades 4, 5, 6) over a 24-month period (2006-2007) were reviewed. DUS findings were considered indicative of hemodynamic stenosis if the peak systolic velocity (PSV) was ≥ 180 cm/s or the PSV velocity ratio was ≥ 2.0. Demographic, clinical, procedural, and outcomes were examined. SVS and TASC II classifications and reporting standards were used. Arteriograms were reviewed and treated segments were categorized as patent (<30% residual stenosis) or abnormal (≥ 30% residual stenosis).

RESULTS

There were 122 infrainguinal interventions for CLI in 113 patients (53% male; mean age 71 years). Risk factors included diabetes: 61%; renal failure: 20%; and smoking (within 1 year): 40%. DUS was performed within 30 days of the index procedure in 90 cases. Fifty patients had an abnormal early duplex and 40 patients had a normal duplex. In patients with a normal duplex ultrasound the amputation rate was 5% vs 20% in the group with an abnormal duplex (P = .04). Primary patency was 56% in the normal duplex group and 46% in the abnormal duplex group (P = .18). Early duplex ultrasound was able to identify a residual stenosis not seen on completion angiography in 56% of cases.

CONCLUSIONS

Duplex scanning detects residual stenosis missed with conventional angiography after infrainguinal interventions. An abnormal DUS in the first 30 days after an intervention is associated with an increased risk of amputation. This suggests a possible role for intraprocedural DUS, as well as routine postprocedure DUS, close clinical follow-up, and consideration of reintervention for residual abnormalities in patients treated for CLI.

Practical use of duplex echo-guided recanalization of chronic total occlusion in the iliac artery

Although endovascular therapy for peripheral arterial disease has undergone tremendous changes, chronic total occlusion (CTO) remains a significant challenge for interventionalists. Failed CTO recanalization is predominately due to unsuccessful guidewire crossing. In particular, the unique characteristics of tortuous and deeply located large vessels in the retroperitoneal cavity create challenging endovascular procedures. Real-time guidance based on external direct vessel visualization might be a promising tool for successful recanalization of noncalcific CTO. Here, we describe the practical use of duplex echo-guidance during the procedural course of iliac CTO recanalization.

Medical and endovascular management of critical limb ischemia

Critical limb ischemia (CLI) is the term used to designate the condition in which peripheral artery disease has resulted in resting leg or foot pain or in a breakdown of the skin of the leg or foot, causing ulcers or tissue loss. If not revascularized, CLI patients are at risk for limb loss and for potentially fatal complications from the progression of gangrene and the development of sepsis. The management of CLI requires a multidisciplinary team of experts in different areas of vascular disease, from atherosclerotic risk factor management to imaging, from intervention to wound care and physical therapy. In the past decade, the most significant change in the treatment of CLI has been the increasing tendency to shift from bypass surgery to less invasive endovascular procedures as first-choice revascularization techniques, with bypass surgery then reserved as backup if appropriate. The goals of intervention for CLI include the restoration of pulsatile, inline flow to the foot to assist wound healing, the relief of rest pain, the avoidance of major amputation, preservation of mobility, and improvement of patient function and quality of life. The evaluating physician should be fully aware of all revascularization options in order to select the most appropriate intervention or combination of interventions, while taking into consideration the goals of therapy, risk-benefit ratios, patient comorbidities, and life expectancy. We discuss the incidence, risk factors, and prognosis of CLI and the clinical presentation, diagnosis, available imaging modalities, and medical management (including pain and ulcer care, pharmaceutical options, and molecular therapies targeting angiogenesis). The endovascular approaches that we review include percutaneous transluminal angioplasty (with or without adjunctive stenting); subintimal angioplasty; primary femoropopliteal and infrapopliteal deployment of bare nitinol, covered, drug-eluting, or bioabsorbable stents; cryoplasty; excimer laser-assisted angioplasty; excisional atherectomy; and cutting balloon angioplasty.

Revascularização endovascular infrainguinal: fatores determinantes para a perviedade

Contexto: A terapia endovascular tem avançado muito como tratamento para a doença arterial oclusiva infrainguinal, principalmente com o desenvolvimento dos materiais e dos stents autoexpansíveis de nitinol. Objetivo: Avaliar os resultados e os fatores determinantes da angioplastia fêmoro-poplítea em pacientes portadores de isquemia de membros inferiores. Métodos: Foram tratados, através de angioplastia com ou sem stent, 114 pacientes, e acompanhados por um período médio de 12 meses. A média de idade foi de 66 anos; 53% eram do sexo feminino; 23,7% eram portadores de claudicação incapacitante; 8,8%, de dor isquêmica de repouso; e 67,5%, de lesão trófica. As lesões foram classificadas segundo o TransAtlantic Inter-Society Consensus II em A (53%), B (34%), C (5%) e D (9%). Resultados: A análise angiográfica do leito distal mostrou uma média de 1,4±1,0 artérias infrapoplíteas pérvias. O sucesso inicial foi de 97%. No seguimento de 1, 6, 12 e 24 meses, a perviedade primária foi de 94, 78, 48 e 31%, e a primária assistida, de 94, 84, 73 e 61%, respectivamente (p = 0,005). O leito distal pobre e a presença de diabetes melito foram associados a uma menor perviedade primária (p = 0,01), enquanto a extensão da lesão não influenciou os resultados. As taxas de salvamento de membro em 6, 12 e 24 meses foram de 95, 90 e 90%, respectivamente. Conclusões: A extensão das lesões tratadas não foi um fator determinante em nossa casuística para o menor sucesso da angioplastia, o que pode sugerir que as indicações para o tratamento endovascular possam ser ampliadas para pacientes com lesões TransAtlantic Inter-Society Consensus II C/D.

Predictive factors of femoropopliteal patency after suboptimal duplex-guided balloon angioplasty and stenting: is recoil a bad sign?

Currently, the value of stenting during femoropopliteal balloon angioplasty (FPBA) remains unclear. Herein we evaluate the patency rates of successful duplex-guided balloon angioplasty (DAGBA) alone versus suboptimal DAGBA followed by stenting and the prestenting dissection versus recoil as potential indicators of stent success or failure. Over a period of 27 months, we performed 291 duplex-guided FPBAs (194 stenoses; 97 occlusions) on 244 limbs in 220 patients. Disabling claudication was the indication in 67%. Critical limb ischemia was the indication in the remaining 33%. Self-expanding nitinol stents were used when plaque dissection and/ or recoil caused diameter reduction > or = 40%. Serial follow-up duplex scans were obtained. Severe restenosis (> 70%) was measured by B-mode imaging and a peak systolic velocity ratio > 3. Follow-up ranged from 1 to 41 months (mean 10 +/- 8.3 months). The overall mean interval for restenosis and occlusion was 6.5 +/- 4.2 months and 5.6 +/- 6.1 months, respectively. Stents did affect overall patency results compared with not using stents. Reasons for stenting were plaque recoil, dissection, or both in 98 (53%), 44 (24%), and 42 (23%) cases, respectively. Six-month patency was 59%, 94%, and 69%, respectively. The difference between plaque recoil and dissection was significant (p<.04). The use of stents during FPBA may be associated with balloon angioplasty site failure in the femoropopliteal segment. To our knowledge, this is the first report ever to document plaque recoil as a predictor of balloon angioplasty site failure notwithstanding stent placement.

Diagnosis and treatment of abdominal aortic endoleaks using color Doppler US: Two clinical cases

Endovascular treatment of abdominal aortic aneurysm (AAA) involves placement of an endoluminal graft inside the aneurysmal sac in order to exclude it from blood circulation and thereby prevent the risk of aneurysmal sac rupture. A possible complication is endoleak, i.e. persistent blood flow outside the lumen of the endograft into the aneurysmal sac. The protocol for treatment monitoring includes abdominal computed tomography (CT) and color Doppler ultrasound (US). The aim of this case report is to present our experience in two cases of endoleak in which diagnosis and treatment were carried out using color Doppler US.