Diagnostic and Therapeutic Approaches in the Management of Infrapopliteal Arterial Disease.

Chronic limb-threatening ischemia represents end-stage peripheral artery disease. It is underdiagnosed; it relies on clinical symptoms and traditional noninvasive tests, which significantly underestimate the severity of disease. Innovative techniques, approaches, technologies, and risk-assessment tools have significantly improved our ability to treat these patients and to better understand their complex disease process. For patients with chronic limb-threatening ischemia considered without options, the reengineering of deep venous arterialization procedures has shown promising results. Finally, the creation of interactive and multidisciplinary teams in centers of excellence is of paramount importance to significantly improve the care and outcomes of these patients.

Tibiopedal arterial minimally invasive retrograde revascularization (TAMI) in patients with peripheral arterial disease and critical limb ischemia. On behalf of the Peripheral Registry of Endovascular Clinical Outcomes (PRIME).

OBJECTIVES AND BACKGROUND: Complex peripheral arterial disease (PAD) and critical limb ischemia (CLI) are associated with high morbidity and mortality. Endovascular techniques have become prevalent in treatment of advanced PAD and CLI, and use of techniques such as tibiopedal minimally invasive revascularization (TAMI), have been proven safe in small, single-center series. However, its use has not been systematically compared to traditional approaches. METHODS AND RESULTS: This is a retrospective, multicenter analysis which enrolled 744 patients with advanced PAD and CLI who underwent 1,195 endovascular interventions between January 2013 and April 2018. Data was analyzed based on access used for revascularization: 840 performed via femoral access, 254 via dual access, and 101 via TAMI. The dual access group had the highest median Rutherford Class and lowest number of patent tibial vessels. Median fluoroscopy time, procedure time, hospital stay, and contrast volume were significantly lower in the TAMI access group when compared to both femoral/dual access groups. There was also a significant difference between all groups regarding location of target lesions: Femoropopliteal lesions were most commonly treated via femoral access; infrapopliteal lesions, via TAMI, and multilevel lesions via dual access. CONCLUSIONS: Stand-alone TAMI or tibial access as an integral part of a dual access treatment strategy, is safe and efficacious in the treatment of patients with advanced PAD and CLI who have infrapopliteal lesions. Larger prospective and randomized studies may be useful to further validate this approach.

Chronic Total Occlusion Crossing Approach Based on Plaque Cap Morphology: The CTOP Classification.

PURPOSE: To present the chronic total occlusion (CTO) crossing approach based on plaque cap morphology (CTOP) classification system and assess its ability to predict successful lesion crossing. METHODS: A retrospective analysis was conducted of imaging and procedure data from 114 consecutive symptomatic patients (mean age 69±11 years; 84 men) with claudication (Rutherford category 3) or critical limb ischemia (Rutherford category 4-6) who underwent endovascular interventions for 142 CTOs. CTO cap morphology was determined from a review of angiography and duplex ultrasonography and classified into 4 types (I, II, III, or IV) based on the concave or convex shape of the proximal and distal caps. RESULTS: Statistically significant differences among groups were found in patients with rest pain, lesion length, and severe calcification. CTOP type II CTOs were most common and type III lesions the least common. Type I CTOs were most likely to be crossed antegrade and had a lower incidence of severe calcification. Type IV lesions were more likely to be crossed retrograde from a tibiopedal approach. CTOP type IV was least likely to be crossed in an antegrade fashion. Access conversion, or need for an alternate access, was commonly seen in types II, III, and IV lesions. Distinctive predictors of access conversion were CTO types II and III, lesion length, and severe calcification. CONCLUSION: CTOP type I lesions were easiest to cross in antegrade fashion and type IV the most difficult. Lesion length >10 cm, severe calcification, and CTO types II, III, and IV benefited from the addition of retrograde tibiopedal access.

Precise Retrograde Supera Stenting of the Ostium (PRESTO) of the Superficial Femoral Artery for Complex Femoropopliteal Occlusions: The PRESTO Technique.

PURPOSE: To describe a novel technique designed to safely and precisely deploy the Supera stent accurately at the ostium of the proximal superficial femoral artery (SFA) without compromising the profunda and common femoral arteries. TECHNIQUE: After antegrade crossing of the chronic total occlusion (CTO) at the SFA ostium and accurate predilation of the entire SFA lesion, a retrograde arterial access is obtained. The Supera stent is navigated in retrograde fashion to position the first crown to be released just at the SFA ostium. Antegrade dilation is performed across the retrograde access site to obtain adequate hemostasis. The technique has been applied successfully in 21 patients (mean age 78.1±8.2 years; 13 men) with critical limb ischemia using retrograde Supera stenting from the proximal anterior tibial artery (n=6), the posterior tibial artery (n=2), retrograde stent puncture in the mid to distal SFA (n=2), the native distal SFA/proximal popliteal segment (n=6), and the distal anterior tibial artery (n=5). No complications were observed. CONCLUSION: Distal retrograde Supera stent passage and reverse deployment allow precise and safe Supera stenting at the SFA ostium.

Drug-coated balloon angioplasty for the management of recurring infrapopliteal disease in diabetic patients with critical limb ischemia.

OBJECTIVE: To describe the 1-year outcomes of recurring infrapopliteal disease after endovascular revascularization with the Lutonix drug-coated balloons (LDCB) in diabetic patients with critical limb ischemia (CLI), and to benchmark our findings with previously published objective performance goals (OPG) addressing safety and efficacy of new catheter-based therapies for CLI. METHODS: The present study was a retrospective, single-center, and single-arm trial of symptomatic diabetic patients with CLI, who underwent LDCB-angioplasty for recurring infrapopliteal disease. Acute procedural and technical success were recorded. TcPO2 metrics variations at baseline and follow up were analyzed. Freedom from clinically driven target lesion revascularization (CD-TLR) was calculated using Kaplan-Meier analysis, and outcomes compared with previously published OPG for infrapopliteal interventions. RESULTS: 21 patients (15 men; mean age 66,6±11,2 years) were followed-up for 356.5±159.2 days and 90.47% had 12-months follow up data available for analysis. TcPO2 increased (14.3±11.6mmHg to 53.8±11.7mmHg; p<0.05). Limb salvage rate was 100%, and 90.4% of patients achieved the combined endpoint of reduction in ulcer size/depth or complete healing. LDCB had superior efficacy (MALE+post-operative death, amputation free survival, freedom from re-intervention, limb salvage and survival rates), while attaining superior or equivalent safety (Major Adverse Limb Events, major adverse cardiovascular events and Amputation) endpoints for the overall, modified clinical and anatomical high-risk groups. CONCLUSIONS: Lutonix DCB is safe and effective for recurring infrapopliteal disease. It outperforms the OPG for CLI patients with clinical and anatomical high-risk features.

Innovations in the Endovascular Management of Critical Limb Ischemia: Retrograde Tibiopedal Access and Advanced Percutaneous Techniques.

PURPOSE OF REVIEW: Retrograde tibiopedal access and interventions have contributed to advance of endovascular techniques to treat critical limb ischemia (CLI) patients. This review encompasses the spectrum from advanced diagnostic imaging and technical therapeutic approaches for infrapopliteal occlusions, to a discussion of current standards and future directions. RECENT FINDINGS: Contemporary studies of infrapopliteal angioplasty show suboptimal short-term and 1-year clinical outcomes. Comparative data is needed to shift the focus from PTA to disruptive treatment modalities that can further improve outcomes. Retrograde pedal access has emerged as an important tool to facilitate successfully percutaneous revascularization and limb salvage in patients with CLI. To efficiently approach the complexity of CLI, new thought processes are needed to change the reigning paradigms. Retrograde tibial-pedal access has shown improvement in the rate of successful revascularizations and is an important tool in the amputation-prevention armamentarium. Additional technologies may further improve success rates. Drug-eluting stents have shown better outcomes than PTA in patients with focal infrapopliteal lesions. Registry data have demonstrated the advantage of several atherectomy devices in the tibial arteries. More recently, bioresorbable vascular scaffolds have been used successfully, and further studies with drug-coated balloons are underway. Interventional operators are now even working in the inframalleolar space to reconstitute the plantar arch. Well-conducted studies are needed to generate high-quality evidence in the field of critical limb ischemia management.

Lack of Association Between Limb Hemodynamics and Response to Infrapopliteal Endovascular Therapy in Patients With Critical Limb Ischemia.

BACKGROUND: Non-invasive limb hemodynamics may aid in diagnosis of critical limb ischemia (CLI), although the relationship with disease severity and response to endovascular therapy is unclear. METHODS AND RESULTS: This prospective, single-center study enrolled 100 CLI patients (Rutherford class 4-6) who underwent infrapopliteal endovascular revascularization (175 lesions) in the Peripheral RegIstry of Endovascular Clinical OutcoMEs (PRIME) registry. Hemodynamic measures included ankle-brachial index (ABI), toe-brachial index (TBI), and toe pressure (TP). Procedure success following revascularization was defined as stenosis ≤30%. Hemodynamic success was defined as an increase >0.15 in ABI or TBI relative to baseline. Freedom from amputation was defined as no major or minor amputation during follow-up. Clinical success was defined as a decrease of at least one Rutherford class during follow-up. Treatment success was defined as procedure success, freedom from amputation, and clinical improvement. Median baseline hemodynamic values were 0.90 for ABI, 0.39 for TBI, and 54 mm Hg for TP. Twenty-nine patients (29%) did not meet the common hemodynamic diagnostic criterion for eligibility in CLI trials (ABI ≤0.5, TBI ≤0.5, or TP <50 mm Hg). Main outcomes included 96% procedure success, 95% freedom from amputation, 64% clinical success, and 62% treatment success. There was no relationship between baseline (or with the pretreatment to posttreatment change) limb hemodynamic values and the response to infrapopliteal endovascular therapy. CONCLUSION: Non-invasive hemodynamic studies may have limited clinical usefulness in patients with CLI. The usefulness of these parameters to confirm eligibility and to assess response to therapy in interventional CLI clinical trials should be re-evaluated.

Infrapopliteal calcification patterns in critical limb ischemia: diagnostic, pathologic and therapeutic implications in the search for the endovascular holy grail.

Critical limb ischemia (CLI) represents the terminal stage of peripheral arterial disease (PAD) and is characterized by multilevel and multivessel disease. Amongst patients with infrainguinal disease, approximately one third have predominantly isolated infrapopliteal disease and the remaining two thirds, a combination of femoropopliteal and infrapopliteal disease. Isolated infrapopliteal disease is mainly seen in the elderly, diabetic, or dialysis-dependent patients. These patients have higher risk of amputation and shorter amputation-free survival. Infrapopliteal disease presents with either complex high-grade calcified tandem lesions in multiple vessels or with long chronic total occlusion (CTO) segments with plaques characterized by higher calcium and lower fibro-fatty content than the inflow vessels, as arterial calcium deposition increases as we progress distally in the arterial tree. Vascular calcification occurs in both intima and media. Intimal calcification leads to development of calcified atheroma and occlusive lesions. Medial calcification leads to stiffening and decrease in arterial wall elasticity and compliance leading to atherosclerosis, reduced perfusion, and PAD, increasing cardiovascular mortality among patients with end-stage renal disease. This article attempts to review the implications of the diverse pathologic patterns of calcium distribution in infrapopliteal vessels of CLI patients, on the diagnostic modalities, technological developments, and the evolution of therapeutic approaches to improve outcomes among these patients. A critical analysis of the currently available data is provided, pointing to the surprising omission on the role of calcium on outcomes, and future directions are discussed. Is infrapopliteal calcium a roadblock or the avenue towards new paths? Necessity remains the mother of invention.

Management of Patients on Non-Vitamin K Antagonist Oral Anticoagulants in the Acute Care and Periprocedural Setting: A Scientific Statement From the American Heart Association.

Non-vitamin K oral anticoagulants (NOACs) are now widely used as alternatives to warfarin for stroke prevention in atrial fibrillation and management of venous thromboembolism. In clinical practice, there is still widespread uncertainty on how to manage patients on NOACs who bleed or who are at risk for bleeding. Clinical trial data related to NOAC reversal for bleeding and perioperative management are sparse, and recommendations are largely derived from expert opinion. Knowledge of time of last ingestion of the NOAC and renal function is critical to managing these patients given that laboratory measurement is challenging because of the lack of commercially available assays in the United States. Idarucizumab is available as an antidote to rapidly reverse the effects of dabigatran. At present, there is no specific antidote available in the United States for the oral factor Xa inhibitors. Prothrombin concentrate may be considered in life-threatening bleeding. Healthcare institutions should adopt a NOAC reversal and perioperative management protocol developed with multidisciplinary input.

Feasibility and 1-Year outcomes of subintimal revascularization with supera® stenting of long femoropopliteal occlusions in critical limb ischemia: The "Supersub" Study.

BACKGROUND: Stent-based revascularization of long femoro-popliteal (FP) lesions has been mainly studied in claudicants and compromised by restenosis and stent fractures. The Supera® stent's biomimetic design allows enhanced fracture resistance. Data for Supera® stenting to treat long chronic total occlusions (CTOs) in patients with critical limb ischemia (CLI), are scarce. OBJECTIVE: To assess long-term outcomes of subintimal revascularization with Supera® stenting, for long FP CTOs in patients with CLI. METHODS: Prospective, single-center, single-arm study of 34 consecutive CLI patients with FP TASC C and D CTOs, who underwent Supera® stenting after subintimal crossing. Primary efficacy endpoint was 1-year patency and freedom from target lesion revascularization (TLR). Primary safety endpoint was the composite rate of freedom from death from any cause, major amputations, and TLR at a year. Secondary endpoints were stent integrity, clinical improvement, amputation free-survival, quality of life, and cost-efficiency. RESULTS: Mean lesion length was 27.9 ± 10.2 cm. Acute technical success was 100%. Primary patency was 94.1%. Freedom from TLR was 97.1%. Limb salvage was 100%. Clinical improvement was observed in 100% of patients: TC PO2 increased from 12.7 ± 6.2 to 54.8 ± 8.4 mm Hg (p < 0,0001); and 100% of patients experienced a shift in Rutherford to class 0 (p < 0.0001). There were no stents fractures. Amputation free-survival was 82.4%. CONCLUSIONS: Subintimal revascularization with Supera® stenting in CLI patients with long FP occlusions, is feasible and superior to validated efficacy performance goals. Larger multicenter studies are needed to validate the safety and efficacy of this novel alternative approach. © 2016 Wiley Periodicals, Inc.

Percutaneous Transluminal Angioplasty in Patients With Infrapopliteal Arterial Disease: Systematic Review and Meta-Analysis.

BACKGROUND: Contemporary outcomes of percutaneous transluminal angioplasty for the treatment of infrapopliteal atherosclerotic lesions are not well characterized. Hence, a systematic review and meta-analysis was performed to determine the safety and effectiveness of this approach in patients with advanced below-the-knee arterial disease. METHODS AND RESULTS: MEDLINE and EMBASE databases were searched for contemporary studies (2005-2015) on the effects of percutaneous transluminal angioplasty for the treatment of infrapopliteal lesions. A random effects meta-analysis model was used to analyze procedural (technical success, flow-limiting dissection, provisional stent placement) and long-term (primary patency, repeat revascularization, major amputation, all-cause mortality) outcomes. Ultimately, 52 studies encompassing 6769 patients with 9399 below-the-knee lesions were included in the analysis. Technical success was 91.1% (95% confidence interval [CI], 88.8-93.0), and the incidence of flow-limiting dissections and bailout stenting was 5.6% (95% CI, 3.2-9.8) and 9.1% (95% CI, 6.3-12.9), respectively. Outcomes at 1 year were primary patency, 63.1% (95% CI, 57.3-68.6); repeat revascularization, 18.2% (95% CI, 14.5-22.6); major amputation, 14.9% (95% CI, 12.3-18.0); and all-cause mortality, 15.1% (95% CI, 12.8-17.7). Significant heterogeneity and publication bias were observed for most percutaneous transluminal angioplasty outcomes. CONCLUSIONS: Contemporary studies of the use of percutaneous transluminal angioplasty as primary treatment for patients with infrapopliteal arterial disease reveal suboptimal procedural and 1-year clinical outcomes.

Ultrasound-Guided Arterial Access: Outcomes Among Patients With Peripheral Artery Disease and Critical Limb Ischemia Undergoing Peripheral Interventions.

OBJECTIVE: Arterial cannulation is a vital component of endovascular interventions and often unconventional access approaches are required due to disease complexity. Historically, varying maneuvers have been utilized to obtain arterial access. Lack of consensus exists regarding the safest and most effective method. This study examined the feasibility and immediate outcomes of ultrasound-guided access in traditional and advanced access approaches. METHODS: Data were analyzed from a cohort of 407 patients enrolled in the Peripheral RegIstry of Endovascular Clinical OutcoMEs (PRIME). The 407 patients underwent 649 procedures with 896 access sites utilized. Access success, immediate outcomes, complications, and length of hospital stay were analyzed. RESULTS: Mean age was 70 years, and 67% were male. The majority of patients had critical limb ischemia (58%), 39% were Rutherford classification III. Most commonly utilized access sites were common femoral retrograde, common femoral antegrade, posterior tibial, and anterior tibial arteries (34.6%, 33.0%, 12.1%, and 12.1%, respectively). Mean number of attempts was 1.2, 1.2, 1.5, and 1.4, respectively; median time to access was 39, 45, 41, and 59 seconds, respectively; and access success rate was 99.4%, 97.3%, 90.7%, and 92.6%; respectively. Access-site combinations utilized were femoral antegrade (n = 188), femoral retrograde (n = 185), dual femoral/ tibio-pedal (n = 130), dual femoral retrograde (n = 44), retrograde tibio-pedal (n = 73), and other (n = 29). Access-related complications were low overall: hematoma (1.2%), bleeding requiring transfusion/intervention (1.7%), pseudoaneurysm (1.7%), arteriovenous fistula (0.3%), aneurysm (0%), compartment syndrome (0%), and death (0%). CONCLUSION: Utilization of ultrasound-guided arterial access in this complex cohort was shown to be safe and effective regardless of arterial bed and approach.

Automated Carbon Dioxide Angiography for the Evaluation and Endovascular Treatment of Diabetic Patients With Critical Limb Ischemia.

PURPOSE: To test the safety, efficacy, and diagnostic accuracy of automated carbon dioxide (CO2) angiography (ACDA) for the evaluation of diabetic patients with critical limb ischemia (CLI) and baseline renal insufficiency and compare ACDA with iodinated contrast medium (ICM) during endovascular treatment. METHODS: From November 2014 to January 2015, 36 consecutive diabetic patients (mean age 74.8±5.8 years; 27 men) with stage ≥3 chronic kidney disease (CKD ≥3) and CLI underwent lower limb angiography with both CO2 and ICM followed by balloon angioplasty in a prospective single-center study. The primary outcome measure was the safety and efficacy of ACDA as the exclusive agent to guide angioplasty in this cohort. The secondary outcomes were the safety and diagnostic accuracy of ACDA injection as compared with ICM digital subtraction angiography (DSA) for invasive evaluation of these patients. RESULTS: ACDA safely and effectively guided angioplasty in all patients without complications. Transcutaneous oxygen pressure improved from 11.8±6.3 to 58.4±7.6 mm Hg (p<0.001). There were no complications related to ACDA during diagnostic imaging and no significant changes in the estimated glomerular filtration rate from baseline to 24 hours (44.7±13.3 vs 47.0±0.8 mL/min/1.73 m(2); nonsignificant). The diagnostic accuracy of CO2 was 89.8% (sensitivity 92.3%; specificity 75%; positive predictive value 95.5%; negative predictive value 63.1%). There was no statistically significant difference in the qualitative diagnostic accuracy between the media (p=0.197). CONCLUSION: ACDA is an accurate, safe, and effective technique that can be utilized to guide endovascular interventions in diabetics with CLI and baseline CKD ≥3. Larger multicenter randomized studies are needed to validate these results.