An update on methods for revascularization and expansion of the TASC lesion classification to include below-the-knee arteries: A supplement to the inter-society consensus for the management of peripheral arterial disease (TASC II): The TASC steering commi

Predictors of major adverse lower limb events in patients with tissue loss secondary to critical limb-threatening ischemia

BACKGROUND

Chronic limb-threatening ischemia (CLTI) is the end-stage of peripheral arterial disease (PAD) posing a high risk for limb loss and mortality. This study aims to evaluate and list possible predictors of major adverse limb events (MALEs) in CLTI patients with tissue loss.

METHODS

This retrospective study included all Rutherford-Becker stage 5 or 6 patients who required foot debridement and revascularization in our department from January 2016 to December 2018. The limbs were classified according to the TASC II, GLASS and WiFI grading systems. The primary composite outcome was MALEs at 2 years. The secondary outcomes included all-cause mortality, primary patency, freedom from reintervention, and major amputation. Kaplan-Meier estimates were used to determine the event rates, and Cox proportional hazards model with the index MALE as a time-dependent covariate was used to search for MALEs predictors.

RESULTS

Of 241 included patients, 19 underwent open surgeries (7.9 %) 207 had endovascular interventions (85.9 %) and 15 required a hybrid approach (6.2 %). On univariate analysis, patients who experienced MALEs (n = 111) more often required hemodialysis (25 vs 15; p = .02), presented with more complex lesions (TASC D on femoropopliteal (p = .05) or below the knee (BTK) arteries (p = .006) with increasing infra-inguinal GLASS Stage (p < .0001)), a history of index limb open (p = .009) or endovascular (p = .049) revascularization, an occluded tibial artery (p = .002 for the posterior tibial and p = .052 for the anterior tibial), or a "desert foot" (p = .02). The CRP level was also higher at admission (p = .001). Technical success of BTK revascularization significantly reduced MALEs (p < .0001) along with the number of patent BTK vessels (p = .0007). Independent predictors of MALEs included hemodialysis (HR = 2.00; 95%CI: 1.14 to 3.39), pulsatile arterial pressure (HR = 1.01; 95%CI: 1.00 to 1.03) and the infra-inguinal GLASS Stage (HR = 2.50; 95%CI: 1.17 to 5.82). We could not correlate our results with the WiFI scores for amputation risk and revascularization benefit.

CONCLUSION

For patients with CLTI at the stage of trophic disorders, with or without a history of index limb revascularization, the GLASS successfully predicted MALEs. Hemodialysis and high pulsatile arterial pressure increased the risk of MALEs. The WiFI score did not demonstrate its interest in this subgroup of patients.

Methods, design, and initial results of an angiographic core lab from VOYAGER-PAD

Background: Anatomy is critical in risk stratification and therapeutic decision making in coronary disease. The relationship between anatomy and outcomes is not well described in PAD. We sought to develop an angiographic core lab within the VOYAGER-PAD trial. The current report describes the methods of creating this core lab, its study population, and baseline anatomic variables. Methods: Patients undergoing lower-extremity revascularization for symptomatic PAD were randomized in VOYAGER-PAD. The median follow up was 2.25 years. Events were adjudicated by a blinded Clinical Endpoint Committee. Angiograms were collected from study participants; those with available angiograms formed this core lab cohort. Angiograms were scored for anatomic and flow characteristics by trained reviewers blinded to treatment. Ten percent of angiograms were evaluated independently by two reviewers; inter-rater agreement was assessed. Clinical characteristics and the treatment effect of rivaroxaban were compared between the core lab cohort and noncore lab participants. Anatomic data by segment were analyzed. Results: Of 6564 participants randomized in VOYAGER-PAD, catheter-based angiograms from 1666 patients were obtained for this core lab. Anatomic and flow characteristics were collected across 16 anatomic segments by 15 reviewers. Concordance between reviewers for anatomic and flow variables across segments was 90.5% (24,417/26,968). Clinical characteristics were similar between patients in the core lab and those not included. The effect of rivaroxaban on the primary efficacy and safety outcomes was also similar. Conclusions: The VOYAGER-PAD angiographic core lab provides an opportunity to correlate PAD anatomy with independently adjudicated outcomes and provide insights into therapy for PAD. (ClinicalTrials.gov Identifier: NCT02504216).

Using Isolated Femoral Bifurcation Endarterectomy or Combined with Bypass Surgery for Patients with Chronic Limb-Threatening Ischemia

Background and Objectives: The aim of this study was to evaluate the clinical outcomes of patients suffering from chronic limb-threatening ischemia (CLTI) and tissue loss treated with primary isolated femoral bifurcation endarterectomy (FBE) or with FBE combined with bypass surgery. Materials and Methods: This retrospective study was performed in a tertiary university-based care centre. Between January 2008 and December 2019, a prospectively collected database of patients suffering from CLTI and tissue loss and undergoing either primary FBE (group A) or FBE in combination with bypass surgery (group B) was analysed. Study endpoints were ulcer healing, primary and secondary patency rate, limb salvage, and survival. Results: In total, FBE was performed in 73 patients and FBE with bypass in 60 patients. Between both groups, there were no significant differences regarding demographic data or the Global Limb Anatomic Staging System (GLASS) grade III and IV of femoropopliteal lesions. After 3 years, ulcer healing could be achieved in 72% of FBE and in 75% of FBE with bypass patients. The primary patency rate was 95% and 91% for FBE and 83% and 80% for FBE with bypass after one and three years, respectively. The 3-year limb-salvage rate was 78% for FBE and 84% for FBE with bypass. The secondary patency rate after one and three years was 99% and 97% for FBE and 93% and 88% for FBE with bypass. Conclusions: FBE and FBE with bypass are equally effective for ulcer healing in cases of combined CFA and superficial femoral artery lesions. There was no significant difference between both groups regarding primary and secondary patency rates, limb salvage rates and ulcer healing. Isolated FBE could be an alternative strategy in patients with higher operative risk.

Predictors of infrapopliteal vein bypass graft revision in patients with chronic limb-threatening ischemia

PURPOSE

Surgical revascularization is the standard treatment for chronic limb-threatening ischemia (CLTI). However, some patients may require reintervention. The Global Anatomic Staging System (GLASS), which evaluates the complexity of infrainguinal lesions, was proposed. This study aimed to identify predictors for graft revision and evaluate whether GLASS impacts vein graft revision.

METHODS

Between 2011 and 2018, CLTI patients who underwent de novo infrapopliteal bypass using autogenous veins were retrospectively analyzed. To assess anatomic complexity with GLASS, femoropopliteal, infrapopliteal, and inframalleolar/pedal (IM) disease grades were determined. The outcomes of patients with or without graft revision were compared. Cox regression analysis was performed.

RESULTS

Thirty-six of the 80 patients underwent reintervention for graft revision. Compared to the non-graft revision group, the graft revision group exhibited significantly higher rates of GLASS stage III (66% vs 81%, p = 0.046) and grade P2 IM disease (25% vs 58%, p = 0.009). Multivariate analysis revealed that IM grade P2 (hazard ratio [HR], 3.35; 95% confidence interval [CI], 1.66-6.75; p = 0.001) and spliced vein grafts (HR, 3.18; 95% CI, 1.43-7.06; p = 0.005) were significantly associated with graft revision.

CONCLUSIONS

This study demonstrated that IM grade P2 and spliced vein grafts were predictors of graft revision. The GLASS stratification of IM disease grade may be useful in optimizing treatment for CLTI.

Risk of Mortality Related to Recurrent Limb Events After Endovascular Revascularization of the Superficial Femoral Artery for Peripheral Artery Disease: The Boston Femoral Artery Endovascular Revascularization Outcomes (Boston FAROUT) Study

Endovascular revascularization of the superficial femoral artery (SFA) may lead to recurrent ischemic syndromes, revascularization, or amputation. The impact of these events on mortality is unknown. We followed all patients having SFA endovascular revascularization for claudication or chronic limb-threatening ischemia in 2 cardiovascular (CV) divisions in Boston, Massachusetts. Any recurrent limb event after the initial SFA revascularization included recurrent claudication (67%), limb ulceration or gangrene (13%), repeat endovascular revascularization (61%), surgical revascularization (15%), or major (9%) or minor amputation (8%). We linked data to the National Death Index to ascertain cause of death grouped into CV mortality, or non-CV mortality. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) from Cox proportional hazards and sub-HRs from Fine-Gray competing risks analyses were clustered by patient. Overall, there were 202 patients with 253 index limb endovascular procedures. A recurrent limb event occurred in 123 limbs (49%) and 93 patients (46%). Patients with and without recurrent limb events had similar numbers of deaths over follow-up (76 [62%] vs 71 [55%], respectively). In multivariable models, recurrent limb event was not related to all-cause death (HR 0.92, 95% CI 0.64 to 1.33), CV death (HR 1.29, 95% CI 0.72 to 1.30), or non-CV death (HR 0.65, CI 0.39 to 1.07). Competing risk analyses suggested male gender and chronic limb-threatening ischemia were more strongly related to CV death, and chronic kidney more strongly related to disease to non-CV death. In conclusion, recurrent limb events, which contribute to patient morbidity, do not increase the risk of all-cause or cause-specific mortality, and should not discourage repeat revascularization to relieve symptoms or ischemia.

Efficacy and Safety of Absorb Everolimus-Eluting Bioresorbable Vascular Scaffold in Peripheral Artery Disease: A Single-Arm Meta-Analysis

PURPOSE

This study aimed to evaluate the benefits and risks of patients with peripheral artery disease (PAD) treated with Absorb everolimus-eluting bioresorbable vascular scaffold (BVS) by analyzing all the published studies on the clinical characteristics of patients with PAD.

MATERIALS AND METHODS

PubMed, Embase, and the Cochrane Library were searched for relevant studies. Efficacy, safety, and basic characteristics were analyzed.

RESULTS

Four studies were included in meta-analysis, including a total number of 155 patients with PAD. The pooled overall primary patency, freedom from target lesion revascularization (TLR), symptom resolution, and wound healing were 90%, 96%, 94%, and 86%, respectively. The pooled perioperative complication and all-cause mortality were 4% and 9%, respectively. Preoperative total occlusion was detected in 43 of 192 lesions (22%). The mean lesion length was 27.26 mm. In terms of comorbidities, the pooled percentage of hypertension, hyperlipidemia, diabetes mellitus, coronary artery disease, chronic kidney disease history, and smoking were 65%, 74%, 49%, 43%, 20%, and 57%, respectively.

CONCLUSION

Among these studies, hypertension, hyperlipidemia, and diabetes mellitus were the most common comorbidities in patients with PAD. The Absorb everolimus-eluting BVS was safe and showed the favorable clinical outcomes in both patency and TLR, especially in infrapopliteal disease with heavy calcification. The conclusions of this meta-analysis still needed to be verified by more relevant studies with more careful design, more rigorous execution, and larger sample size.

Endovascular Revascularization and Outcomes of Critical Limb-Threatening Ischemia in Trinidad and Tobago: The EVENT Pilot Study-Challenges in a Limited-Resource, Caribbean Setting

INTRODUCTION

This retrospective study investigated major adverse limb events (MALE) and mortality outcomes in critical limb-threatening ischemia (CLTI) patients with tissue loss after an endovascular revascularization-first (EVR-1st) strategy.

METHODS

MALE and mortality were assessed in 157 consecutive patients with CLTI and tissue loss from June 2019 to June 2022 at the Eric Williams Medical Sciences Complex, Trinidad and Tobago.

RESULTS

157 patients underwent the EVR-1st strategy, of whom 20 were pivoted to immediate surgical revascularization (SR). Of the remaining 137 patients, successful EVR was achieved in 112, giving a procedural success of 82% and an all-comer overall success of 71%. The mortality and MALE rates were 2.7% and 8.9% at 2 years, respectively. Males and patients with previous major amputations were at significantly higher risk for MALE (p values of 0.016 and 0.018, respectively). There was a statistically significant difference in successful EVR for both Rutherford-Baker (RB) 5 (minor) and RB 6 (major) classifications: 63 (56%) vs. 5 (20%) and 49 (44%) vs. 20 (80%), both with a p value of 0.01. There were no differences in successful EVR amongst Wound, Ischemia, Foot Infection (WIfI) clinical stages. There were no differences in successful EVR amongst the Trans-Atlantic Inter-Society Consensus (TASC II) classifications.

CONCLUSIONS

This study may prove clinically informative and applicable for an EVR-1st management strategy for high-risk patients with CLTI in a limited-resource, Caribbean setting.

TRIAL REGISTRATION NUMBER

NCT05547022 (retrospectively registered).

Poor inter-observer agreement in anatomical classifications of infrapopliteal arterial disease due to mandatory selection of only one target artery

BACKGROUND

Established anatomical classifications of infrapopliteal arterial lesion severity are based on assessment of only one target artery, not including all infrapopliteal arteries although multivessel revascularization is common.

PURPOSE

To investigate the reproducibility of one of these classifications and a new aggregated score.

MATERIAL AND METHODS

A total of 68 patients undergoing endovascular infrapopliteal revascularization at Sahlgrenska University Hospital during 2008-2016 were included. Preoperative magnetic resonance angiographies (MRA) and digital subtraction angiographies (DSA) were evaluated by three blinded observers in random order, using the infrapopliteal TransAtlantic Inter-Society Consensus (TASC) II classification. An aggregated score, the Infrapopliteal Total Atherosclerotic Burden (I-TAB) score, including all infrapopliteal arteries, was constructed and used for comparison.

RESULTS

Inter-observer agreement on lesion severity for each evaluated artery was good; Krippendorff's α for MRA 0.64-0.79 and DSA 0.66-0.84. Inter-observer agreement on TASC II grade, based on the selected target artery as stipulated, was poor; Krippendorff's α 0.14 (95% confidence interval [CI]=-0.05 to 0.30) for MRA and 0.48 (95% CI=0.33-0.61) for DSA. Inter-observer agreement for the new I-TAB score was good; Krippendorff's α 0.76 (95% CI=0.70-0.81) for MRA and 0.79 (95% CI=0.74-0.84) for DSA.

CONCLUSION

Reproducible assessment of infrapopliteal lesion severity can be achieved for separate arteries with both MRA and DSA using the TASC II definitions. However, poor inter-observer agreement in selecting the target artery results in low reproducibility of the overall infrapopliteal TASC II grade. An aggregated score, such as I-TAB, results in less variability and may provide a more robust evaluation tool of atherosclerotic disease severity.

Lower-limb peripheral arterial disease and amputations in people with diabetes: Risk factors, prognostic value and management

Lower-limb peripheral arterial disease (PAD), is a common manifestation of systemic atherosclerosis, resulting from a partial or complete obstruction of at least one lower-limb arteries. PAD is a major endemic disease with an excess risk of major cardiovascular events and death. It also leads to disability, high rates of lower-limb adverse events and non-traumatic amputation. In patients with diabetes, PAD is particularly frequent and has a worse prognosis than in patients without diabetes. The risk factors of PAD are comparable to those for cardiovascular disease. The ankle-brachial index is usually recommended to screen PAD despite its limited performance in patients with diabetes, affected by the presence of peripheral neuropathy, medial arterial calcification, incompressible arteries and infection. Toe brachial index and toe pressure emerge as alternative screening tools. The management of PAD requires strict control of cardiovascular risk factors including diabetes, hypertension and dyslipidaemia, the use of antiplatelet agents and lifestyle management, to reduce cardiovascular adverse events, but few randomized controlled trials have evaluated the benefits of these treatments in PAD. Several advances have been achieved in endovascular and surgical revascularization procedures, with obvious improvement in PAD prognosis. Further studies are required to increase our understanding of the pathophysiology of PAD and to evaluate the interest of different therapeutic strategies in the occurrence and progression of PAD in patients with diabetes. Here, we present a narrative and contemporary review to synthesize the key epidemiology findings, screening and diagnosis methods, and major therapeutic advances regarding PAD in patients with diabetes.

Underutilization of Drug-Eluting Stents in Infrapopliteal Intervention for Chronic Limb-Threatening Ischemia

PURPOSE

Multiple randomized clinical trials have shown superiority of drug-eluting stents (DES) over bare-metal stents (BMS) for infrapopliteal disease. However, real-world data on DES utilization and outcomes in infrapopliteal chronic limb-threatening ischemia (CLTI) patients are unknown.

MATERIALS AND METHODS

We utilized the Nationwide Readmission Database (NRD) from 2016 to 2017 to extract patients undergoing infrapopliteal intervention with stents (BMS and DES) for CLTI using appropriate ICD-10 codes. Multilevel logistic regression with hospital ID as random effect was used to assess DES utilization. Primary outcome was the composite of target limb major amputation (TLmajA) and target limb revascularization (TLR). Multivariate Cox-proportional hazard regression was used to adjust for confounders.

RESULTS

Our study included a total of 1817 patients. Of these patients, 1056 patients (58.1%) received DES; DES utilization was stable (relative change: +2.5%, p-trend: 0.867) between 2016 and 2017 and was higher in teaching hospitals (adjusted odds ratio [aOR] = 1.28, 95% CI = 1.03-1.61, p=0.029] and medium (aOR = 3.13, 95% CI = 2.17-4.55, p≤0.001) and large (aOR = 1.56, 95% CI = 1.14-2.17, p=0.005) bed-sized hospitals. Inter-class correlation was 0.44 suggesting ~44% variation in DES utilization between any 2 random hospitals; DES was associated with lower rate of the primary composite outcome (aHR = 0.75, 95% CI = 0.62-0.92, p=0.004) compared with BMS.

CONCLUSION

In patients undergoing infrapopliteal intervention for CLTI, DES demonstrated significant underutilization despite supportive evidence of their superiority compared with BMS; DES was associated with improvement in the primary composite outcome compared with BMS.

The Neuro-Ischaemic Charcot Foot: Prevalence, Characteristics and Severity of Peripheral Arterial Disease in Acute Charcot Neuro-Arthropathy

The study aimed to evaluate the prevalence, characteristics and outcomes of patients affected by Charcot neuro-arthropathy (CN) and peripheral arterial disease (PAD) compared to CN without PAD. Consecutive patients presenting with an acute CN were included. The sample size was calculated by the power analysis by adopting the two-tailed tests of the null hypothesis with alfa = 0.05 and a value of beta = 0.10 as the second type error and, therefore, a test power equal to 90%. Seventy-six patients were identified. Twenty-four patients (31.6%) had neuro-ischaemic CN; they were older (66 vs. 57yrs), p = 0.03, had a longer diabetes duration (19 vs. 14yrs), p < 0.001, and more cases of end-stage-renal-disease (12.5 vs. 0%), p = 0.04 and ischaemic heart disease (58.3 vs. 15.4%), p < 0.0001 than neuropathic CN. Fifty patients (65.8%) had concomitant foot ulcers, 62.5% and 67.3% (p = 0.3), respectively, in CN with and without PAD. Neuro-ischaemic CN show arterial lesions of 2.9 vessels, and PAD was located predominantly below-the-knee (75%) but not below-the-ankle (16.7%). The outcomes for neuro-ischaemic and neuropathic CN patients were, respectively: wound healing (86.7 vs. 94.3%), p = 0.08; minor amputation (25 vs. 7.7%), p = 0.003; major amputation (8.3 vs. 1.9%), p = 0.001; hospitalization (75 vs. 23%), p = 0.0001. The study showed a frequent association between CN and PAD, leading to a neuro-ischaemic Charcot foot type. Neuro-ischaemic CN leaded to an increased risk of minor and major amputation and hospitalization, compared to neuropathic CN.

Prediction of 2-Year Major Adverse Limb Event-Free Survival After Percutaneous Transluminal Angioplasty and Stenting for Lower Limb Atherosclerosis Obliterans: A Machine Learning-Based Study

Background

The current scoring systems could not predict prognosis after endovascular therapy for peripheral artery disease. Machine learning could make predictions for future events by learning a specific pattern from existing data. This study aimed to demonstrate machine learning could make an accurate prediction for 2-year major adverse limb event-free survival (MFS) after percutaneous transluminal angioplasty (PTA) and stenting for lower limb atherosclerosis obliterans (ASO).

Methods

A lower limb ASO cohort of 392 patients who received PTA and stenting was split to the training set and test set by 4:1 in chronological order. Demographic, medical, and imaging data were used to build machine learning models to predict 2-year MFS. The discrimination and calibration of artificial neural network (ANN) and random forest models were compared with the logistic regression model, using the area under the receiver operating curve (ROCAUC) with DeLong test, and the calibration curve with Hosmer–Lemeshow goodness-of-fit test, respectively.

Results

The ANN model (ROCAUC = 0.80, 95% CI: 0.68–0.89) but not the random forest model (ROCAUC = 0.78, 95% CI: 0.66–0.87) significantly outperformed the logistic regression model (ROCAUC = 0.73, 95% CI: 0.60–0.83, P = 0.01 and P = 0.24). The ANN model the logistic regression model demonstrated good calibration performance (P = 0.73 and P = 0.28), while the random forest model showed poor calibration (P < 0.01). The calibration curve of the ANN model was visually the closest to the perfectly calibrated line.

Conclusion

Machine learning models could accurately predict 2-year MFS after PTA and stenting for lower limb ASO, in which the ANN model had better discrimination and calibration. Machine learning-derived prediction tools might be clinically useful to automatically identify candidates for PTA and stenting.

Team-Based Care in Patients with Chronic Limb-Threatening Ischemia

PURPOSE OF REVIEW

Team-based care has been proposed as a tool to improve health care delivery, especially for the treatment of complex medical conditions. Chronic limb-threatening ischemia (CLTI) is a complex disease associated with significant morbidity and mortality which often involves the care of multiple specialty providers. Coordination of efforts across the multiple physician specialists, nurses, wound care specialists, and administrators is essential to providing high-quality and efficient care. The aim of this review is to discuss the multiple facets of care of the CLTI patient and to describe components important for a team-based care approach.

RECENT FINDINGS

Observational studies have reported improved outcomes when using a team-based care approach in the care of the patients with CLTI, including reduction in mean wound healing times, decreasing rate of amputations, and readmissions. Team-based care can streamline care of CLTI patients by raising awareness, facilitating early recognition, and providing prompt vascular assessment, revascularization, and surveillance. This approach has the potential to improve patient outcomes and reduce downstream health care costs.

EndoNaut two-dimensional fusion imaging with a mobile C-arm for endovascular treatment of occlusive peripheral arterial disease

BACKGROUND

Endovascular treatment has become the first-line strategy for peripheral arterial disease (PAD). Given the number of procedures required, any technology associated with a reduction in radiation exposure and contrast volume is highly relevant. In the present study, we evaluated whether two-dimensional (2D) fusion imaging could reduce the radiation exposure and contrast volume during endovascular treatment of occlusive PAD.

METHODS

Our consecutive, retrospective, single-center, nonrandomized comparative trial included patients with PAD at the femoral, popliteal, and/or tibial level, at any clinical stage, if they were candidates for endovascular revascularization. Patients were treated with or without the EndoNaut 2D fusion imaging system (Therenva, Rennes, France) in a nonhybrid room with the same Cios Alpha mobile C-arm (Siemens, Munich, Germany). The indirect dose-area product and contrast medium volume were recorded.

RESULTS

Between March 2018 and April 2020, 255 patients underwent endovascular femoropopliteal revascularization with (n = 124) or without (n = 131) 2D fusion imaging. The volume of injected contrast medium (34.7 ± 13.8 mL vs 51.3 ± 26.7 mL; P < .001) and dose-area product (8.9 ± 9.9 Gy/cm² vs 13.5 ± 14.0 Gy/cm²; P = .003) were significantly lower for the 2D fusion imaging group than for the control group. A subgroup analysis of complex (TransAtlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease C/D) lesions showed similar results. Stratification of the fusion imaging group into three subgroups, according to the procedure dates, showed no effect of a potential learning curve on the operative parameters.

CONCLUSIONS

The results from the present study showed a significant reduction in the contrast volume and radiation dose for endovascular treatment of PAD when applying 2D fusion imaging technology. Overall, a reduction of >30% was observed for both operative parameters, without excessive training requirements, highlighting the potential benefits of using 2D fusion imaging when performing endovascular revascularization for PAD.

The Global Limb Anatomic Staging System (GLASS) for CLTI: Improving Inter-Observer Agreement

Objective: The 2020 Global Vascular Guidelines aim at improving decision making in Chronic Limb-Threatening Ischemia (CLTI) by providing a framework for evidence-based revascularization. Herein, the Global Limb Anatomic Staging System (GLASS) serves to estimate the chance of success and patency of arterial pathway revascularization based on the extent and distribution of the atherosclerotic lesions. We report the preliminary feasibility results and observer variability of the GLASS. GLASS is a part of the new global guideline and posed as a promising additional tool for EBR strategies to predict the success of lower extremity arterial revascularization. This study reports on the consistency of GLASS scoring to maximize inter-observer agreement and facilitate its application. Methods: GLASS separately scores the femoropopliteal (FP) and infrapopliteal (IP) segment based on stenosis severity, lesion length and the extent of calcification within the target artery pathway (TAP). In our stepwise approach, we used two angiographic datasets. Each following step was based on the lessons learned from the previous step. The primary outcome was inter-observer agreement measured as Cohen’s Kappa, scored by two (step 1 + 2) and four (step 3) blinded and experienced observers, respectively. Steps 1 (n = 139) and 2 (n = 50) were executed within a dataset of a Dutch interventional RCT in CLTI. Step 3 (n = 100) was performed in randomly selected all-comer CLTI patients from two vascular centers in the United States. Results: In step 1, kappa values were 0.346 (FP) and 0.180 (IP). In step 2, applied in the same dataset, the use of other experienced observers and a provided TAP, resulted in similar low kappa values 0.406 (FP) and 0.089 (IP). Subsequently, in step 3, the formation of an altered stepwise approach using component scoring, such as separate scoring of calcification and adding a ruler to the images resulted in kappa values increasing to 0.796 (FP) and 0.730 (IP). Conclusion: This retrospective GLASS validation study revealed low inter-observer agreement for unconditioned scoring. A stepwise component scoring provides acceptable agreement and a solid base for further prospective validation studies to investigate how GLASS relates to treatment outcomes.

Use of drug-eluting stents in patients with critical limb ischemia and infrapopliteal arterial disease: a real-world single-center experience

BACKGROUND

Although no drug-eluting stent (DES) has been approved by the Food and Drug Administration to treat infrapopliteal arterial disease, several industry-sponsored trials have reported the outcomes with the use of paclitaxel or sirolimus DESs. To the best of our knowledge, only one study to date has reported on the use of everolimus DESs for infrapopliteal arterial disease. In the present study, we analyzed the clinical outcomes with everolimus DESs in our real-world, single-center experience.

METHODS

A total of 107 limbs with critical limb threatening ischemia (98 patients; 118 lesions) treated with DESs (Xience; Abbott Vascular, Santa Clara, Calif) were analyzed. The postoperative early outcomes, major adverse limb events (above the ankle limb amputation or major intervention at 1 year), and major adverse events (death, amputation, target lesion thrombosis or reintervention) were analyzed. Kaplan-Meier analysis was used to estimate the primary patency rates (using duplex ultrasound), amputation-free rates, and amputation-free survival rates.

RESULTS

Of the 118 lesions treated, 33% were in the anterior tibial artery, 28% were in the tibioperoneal (TP) artery, 21% were in the posterior tibial artery, 8% were in the peroneal artery, 5% were in the TP/posterior tibial artery, 4% were in the TP artery/PA, and 1% were in the TP/anterior tibial artery. The mean lesion length was 41 mm, and 59% were totally occluded (41% stenotic). The mean follow-up was 18.5 months (range, 1-70 months). The overall postoperative complication rate was 11% (2% major amputations), with 2% mortality. Late symptom improvement of one or more Rutherford category was obtained in 71%. The major adverse events rate at 30 days and 1 year was 12% and 45%, respectively. The major adverse limb events rate at 1 year was 15%. The overall primary patency rate was 42%. The primary patency rate at 1, 2, and 3 years was 57%, 45%, and 33%, respectively. The major amputation-free and overall amputation-free survival rates were 87%, 80%, and 77% and 76%, 65%, and 61% at 1, 2, and 3 years, respectively.

CONCLUSIONS

The clinical outcomes after DES (Xience; Abbott Vascular) for infrapopliteal lesions were somewhat satisfactory at 1 year but inferior to the previously reported outcomes, especially at 3 years. Further data with long-term follow-up are needed.

Advances in Revascularization for Peripheral Artery Disease: Revascularization in PAD

Effective revascularization of the patient with peripheral artery disease is about more than the procedure. The approach to the patient with symptom-limiting intermittent claudication or limb-threatening ischemia begins with understanding the population at risk and variation in clinical presentation. The urgency of revascularization varies significantly by presentation; from patients with intermittent claudication who should undergo structured exercise rehabilitation before revascularization (if needed) to those with acute limb ischemia, a medical emergency, who require revascularization within hours. Recent years have seen the rapid development of new tools including wires, catheters, drug-eluting technology, specialized balloons, and biomimetic stents. Open surgical bypass remains an important option for those with advanced disease. The strategy and techniques employed vary by clinical presentation, lesion location, and lesion severity. There is limited level 1 evidence to guide practice, but factors that determine technical success and anatomic durability are largely understood and incorporated into decision-making. Following revascularization, medical therapy to reduce adverse limb outcomes and a surveillance plan should be put in place. There are many hurdles to overcome to improve the efficacy of lower extremity revascularization, such as restenosis, calcification, microvascular disease, silent embolization, and tools for perfusion assessment. This review highlights the current state of revascularization in peripheral artery disease with an eye toward technologies at the cusp, which may significantly impact current practice.

Wound outcomes and factors associated with wound healing after first-time femoropopliteal artery intervention in patients with ischemic tissue loss

BACKGROUND/OBJECTIVE

This study's goal is to describe wound outcomes at 2 years following intervention for atherosclerotic femoropopliteal lesions in patients with ischemic tissue loss.

METHODS

A retrospective review of 135 first-time endovascular procedures for chronic femoropopliteal atherosclerotic lesions related to ischemic tissue loss was performed. The final wound outcomes were categorized according to the initial wound healing, recurrence and the need of major/minor amputation.

RESULTS

At 2-years of follow up, 76 limbs (56.3%) showed complete wound healing without recurrence, however, wound development occurred at other sites on the same foot following complete primary healing in 11 limbs (8.1%). Tolerable wounds persisted or wounds recurred at the same site in 30 limbs (22.2%), and 18 limbs (13.3%) needed major amputations. Independent factors that prevented wound healing without recurrence at 2 years were renal insufficiency (HR = 0.225, 95% C.I. = 0.091-0.556, p = 0.001), ankle pressure < 50 mmHg or flat forefoot PVR (HR = 0.328, 95% C.I. = 0.124-0.867, p = 0.025) and functional performance < 4 metabolic equivalents (MET) (HR = 0.150, 95% C.I. = 0.063-0.360, p < 0.001).

CONCLUSION

Wound outcome classifications showed detailed information regarding clinical outcomes in patients with ischemic tissue loss. Renal insufficiency, ischemia grade 3 and poor functional performance were independent risk factors that prevented wound healing.

Endovascular Therapy for Arteriogenic Erectile Dysfunction With a Novel Sirolimus-Eluting Stent

BACKGROUND

Arteriogenic erectile dysfunction is a common disease oftentimes not satisfactory treatable with medical therapy.

AIM

To assess the safety and clinical success rate of endovascular revascularization of erection-related arteries with the angiolite BTK stent in patients with arteriogenic erectile dysfunction.

METHODS

A total of 100 consecutive men (61.8 ± 10 years) with atherosclerotic lesions in erection-related arteries agreed to participate and were included into a single-center all-comers registry. Endovascular therapy with angiolite BTK drug-eluting stents was performed on a total of 211 lesions. Patients received a baseline International Index of Erectile Function (IIEF)-15 questionnaire at first presentation and 3 and 12 months after stenting. An improvement by 4 points in the erectile function domain consisting of 6 questions (IIEF-6) was defined as minimal clinically important difference. A total of 24 patients with 52 stented arterial lesions underwent angiographic follow-up of the initially treated arterial side during secondary revascularization of the contralateral side (angiographic sub-study).

OUTCOME

Clinical improvement of erections in 100 patients undergoing endovascular revascularization of erection-related arteries.

RESULTS

No major adverse events occurred during endovascular revascularization or within 30 days thereafter. Technical success was achieved in all lesions and procedural success in all patients. At 1 year, 55 of 97 patients (56.7%) improved by at least 4 points in IIEF-6 score and thus achieved a clinically relevant improvement of erectile function.In the angiographic sub-study, arterial patency and binary restenosis were observed in 46 of 52 (88.5%) and in 8 of 52 (15.4%), respectively, after a mean follow-up of 9.6 ± 5.8 months.

CLINICAL IMPLICATIONS

In patients with arteriogenic erectile dysfunction, endovascular therapy with a novel thin-strut sirolimus eluting stent is a safe and feasible treatment option.

STRENGTHS & LIMITATIONS

This real-world arterial revascularization registry included patients with a multitude of risk factors for ED, thereby representing the heterogeneity in patients in the clinical practice, which is one of its strengths but also one of its weaknesses. Another strength was the focus being laid on analyzing outcomes of patients with arteriogenic ED using only a single endovascular device. Further studies are warranted to better define subgroups of patients with impaired clinical outcomes.

CONCLUSION

Within the present all-comers registry, endovascular therapy of erectile dysfunction with the angiolite BTK stent was shown to be a safe and feasible treatment option resulting in clinical improvement rates comparable to earlier clinical trials although also showing that further research is warranted to define patient subgroups with particular benefits of endovascular therapy. Schönhofen J, Räber L, Knöchel J, et al. Endovascular Therapy for Arteriogenic Erectile Dysfunction With a Novel Sirolimus-Eluting Stent. J Sex Med 2021;18:315-326.

The triglyceride-glucose index predicts peripheral artery disease complexity

Background/aim

High levels of triglyceride (TG) and fasting blood glucose (FBG) values increase atherosclerosis risk. This study evaluates the relationship between peripheral artery disease (PAD) severity and complexity, as assessed by TransAtlantic InterSociety Consensus-II (TASC-II) classification and the triglyceride-glucose (TyG) index.

Materials and methods

A total of 71 consecutive patients with PAD (males 93%, mean age 63.3 ± 9.7), who underwent percutaneous peripheral intervention were included retrospectively. The patients were divided into two groups according to the angiographically detected lesions. Those with TASC A-B lesions were included in Group 1, and those with TASC C-D lesions were included in Group 2. TyG index was calculated as formula: ln[fasting TG (mg/dL) × fasting plasma glucose (mg/dL)/2].

Results

There were 40 patients in Group 1 (90.3% men, with a mean age of 63.6 ± 9.3 years) and 31 patients in Group 2 (96.8% men, with a mean age of 62.0 ± 8.6 years). In the majority of patients in both groups, the target vessels are iliac arteries and femoral arteries. In Group 2, platelet count and TyG index were significantly high, according to Group 1. The TyG index was significantly correlated with TASC-II, Rutherford category, HbA1c, and HDL-C.

Conclusion

In this present study, we showed that the TyG index was an independent predictor of peripheral artery disease complexity, according to TASC-II classification, for the first time in the literature.

Therapeutic Angiogenesis with Sound Waves

Along with the progress of global aging, the prognosis of severe ischemic heart disease (IHD) remains poor, and thus the development of effective angiogenic therapy remains an important clinical unmet need. We have developed low-energy extracorporeal cardiac shock wave therapy as an innovative minimally invasive angiogenic therapy and confirmed its efficacy in a porcine chronic myocardial ischemia model in animal experiments as well as in patients with refractory angina. Since ultrasound is more advantageous for clinical application than shock waves, we then aimed to develop ultrasound therapy for IHD. We demonstrated that specific conditions of low-intensity pulsed ultrasound (LIPUS) therapy improve myocardial ischemia in animal models through the enhancement of angiogenesis mediated by endothelial mechanotransduction. To examine the effectiveness of our LIPUS therapy in patients with severe angina pectoris, we are now conducting a prospective multicenter clinical trial in Japan. Furthermore, to overcome the current serious situation of dementia pandemic but with no effective treatments worldwide, we have recently demonstrated that our LIPUS therapy also improves cognitive impairment in mouse models of Alzheimer's disease and vascular dementia. Here, we summarize the progress in our studies to develop angiogenic therapies with sound waves.

Multivessel tibial revascularization does not improve outcomes in patients with critical limb ischemia

OBJECTIVE

Multivessel tibial revascularization for critical limb ischemia (CLI) remains controversial. The purpose of this study was to evaluate single vs multiple tibial vessel interventions in patients with multivessel tibial disease. We hypothesized that there would be no difference in amputation-free survival between the groups.

METHODS

Using the Vascular Quality Initiative registry, we reviewed patients undergoing lower extremity endovascular interventions involving the tibial arteries. Patients with CLI were included only if at least two tibial vessels were diseased and adequate perioperative data and clinical follow-up were available for review. The primary outcome was amputation-free survival.

RESULTS

There were 10,849 CLI patients with multivessel tibial disease evaluated from 2002 to 2017; 761 limbs had adequate data and follow-up available for review. Mean follow-up was 337 ± 62 days. Of these, 473 (62.1%) underwent successful single-vessel tibial intervention (group SV), whereas 288 (37.9%) underwent successful multivessel (two or more) intervention (group MV). Patients in group MV were younger (69.1 vs 73.2 years; P < .001), with higher tobacco use (29.5% vs 18.2%; P < .001). Group SV more commonly had concurrent femoral or popliteal inflow interventions (83.7% vs 78.1%; P = .05). Multivessel runoff on completion was significantly greater for group MV (99.9% vs 39.9%; P < .001). No differences were observed between group SV and group MV for major amputation (9.0% and 7.6%; P = .6), with similar amputation-free survival at 1 year (90.6% vs 92.9%; P = .372). In a multivariate Cox model, loss of patency was the only significant predictor of major amputation (hazard ratio, 5.36 [2.7-10.6]; P = .01). A subgroup analysis of 355 (46.6%) patients with tissue loss data showed that tissue loss before intervention was not predictive of future major amputation.

CONCLUSIONS

In the Vascular Quality Initiative registry, patients with CLI and occlusive disease involving multiple tibial vessels did not appear to have a limb salvage benefit from multiple tibial revascularization compared with single tibial revascularization.

Medical adjunctive therapy for patients with chronic limb-threatening ischemia: a systematic review

INTRODUCTION

The aim of this article is to systematically review the literature on medical adjunctive therapy for patients with chronic limb-threatening ischemia (CLTI).

EVIDENCE ACQUISITION

MEDLINE, Embase, and Cochrane Database of Systematic Reviews were searched for studies published between January 1st, 2009, and June 1st, 2019. Articles that studied medical treatment of CLTI patients and reported clinical outcomes were eligible. Main exclusion criteria were case reports <20 patients, incorrect publication type, and CLTI caused by Buerger disease. The primary end point was major amputation (above the ankle) in studies with a follow-up of ≥6 months. Secondary end points were other clinical end points such as death and wound healing. Study quality was assessed according to the Downs and Black checklist.

EVIDENCE SYNTHESIS

Included were 42 articles: four focused on antiplatelet therapy, five on antihypertensive medication, 6 on lipid-lowering therapy, 16 on stem cell therapy, three on growth factors, five on prostanoids, and one study each on cilostazol, glucose-lowering therapy, spinal cord stimulation, sulodexide, and hemodilution. Calcium channel blockers, iloprost, cilostazol, and hemodilution showed significant improvement of limb salvage, but data are limited. Stem cell therapy showed no significant improvement of limb salvage but could potentially improve wound healing. Antiplatelets, antihypertensives, and statins showed significantly lower cardiovascular events rates but not evident lower major amputation rates. The quality of the studies was fair to good.

CONCLUSIONS

Certain medical therapies serve to improve limb salvage next to revascularization in CLTI patients, whereas others are important in secondary prevention. Because high quality evidence is limited, further research is needed.

The progression rate of peripheral arterial disease in patients with intermittent claudication: a systematic review

Background

Intermittent claudication (IC) is the most common symptom of peripheral arterial disease and is generally treated conservatively due to limited prognostic evidence to support early revascularisation in the individual patient. This approach may lead to the possible loss of opportunity of early revascularisation in patients who are more likely to deteriorate to critical limb ischaemia. The aim of this review is to evaluate the available literature related to the progression rate of symptomatic peripheral arterial disease.

Methods

We conducted a systematic review of the literature in PubMed and MEDLINE, Cochrane library, Elsevier, Web of Science, CINAHL and Opengrey using relevant search terms to identify the progression rate of peripheral arterial disease in patients with claudication. Outcomes of interest were progression rate in terms of haemodynamic measurement and time to development of adverse outcomes. Two independent reviewers determined study eligibility and extracted descriptive, methodologic, and outcome data. Quality of evidence was evaluated using the Cochrane recommendations for assessing risk of bias and was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

Results

Seven prospective cohort studies and one retrospective cohort study were identified and included in this review with the number of participants in each study ranging from 38 to 1244. Progression rate reports varied from a yearly decrease of 0.01 in ankle-brachial pressure index (ABPI) to a yearly decrease ABPI of 0.014 in 21% of participants. Quality of evidence ranged from low to moderate mostly due to limited allocation concealment at recruitment and survival selection bias.

Conclusions

Progression of PAD in IC patients is probably underestimated in the literature due to study design issues. Predicting which patients with claudication are likely to deteriorate to critical limb ischaemia is difficult since there is a lack of evidence related to lower limb prognosis. Further research is required to enable early identification of patients at high risk of progressing to critical ischaemia and appropriate early revascularisation to reduce lower limb morbidity.

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.

A Review of Distribution of Atherosclerosis in the Lower Limb Arteries of Patients With Diabetes Mellitus and Peripheral Vascular Disease

OBJECTIVE

There is a generally accepted hypothesis that patients with diabetes mellitus (DM) have a higher burden of atherosclerotic disease below the knee compared to patients without DM (NDM). The aim of this review was to summarize the evidence regarding this hypothesis.

METHODS

The literature was searched for papers that compared the anatomical distribution of atherosclerotic disease in patients with DM and those without using radiological imaging. Search terms used included "diabetes mellitus," "peripheral vascular disease," "distribution of disease," "angiography," "computed tomography angiography," and "magnetic resonance angiography." Where possible, the number of patients with disease in each arterial segment was extracted and included in a forest plot. A descriptive approach was taken when this was not possible or a scoring system was used.

RESULTS

Fourteen studies were included in the review and it was possible to summarize data from 9 of these in a forest plot. Fifteen different arterial segments were described; however, the most commonly used segments that differentiated between proximal and distal disease were aortoiliac (A-I; DM = 466 patients, NDM = 458), femoropopliteal (F-P; DM = 568, NDM = 585), tibial (DM = 306, NDM = 417). The resulting forest plot showed that those with DM were significantly less likely to have disease in the A-I segment (odds ratio [OR]: 0.25 [0.15-0.42]) and significantly more likely to have disease in the tibial segment (OR 1.94 [1.27-2.96]). In the DM group, there was a trend toward relative sparing in the F-P segment, but this does not reach significance (0.66 [0.33-1.31]).

CONCLUSIONS

These results support the hypothesis that patients with DM are more likely to have atherosclerotic disease in the tibial vessels than NDM. There is however limited information on how individual vessels are affected. Further information on this and a greater understanding of why the distal vessels are more affected are avenues for future research.

Magnetic resonance imaging characteristics of lesions relate to the difficulty of peripheral arterial endovascular procedures

OBJECTIVE

Limitations with current peripheral arterial imaging modalities make selection of patients for percutaneous vascular interventions difficult. The purpose of this study was to determine whether a novel preprocedural magnetic resonance imaging (MRI) method can identify lesions that would be more challenging to cross during percutaneous vascular intervention.

METHODS

Fourteen patients with peripheral arterial disease underwent MRI before their intervention. A novel steady-state free precession flow-independent magnetic resonance (MR) angiogram was used to locate lesions, and an ultrashort echo time image was used to characterize hard lesion components including calcium and dense collagen. Lesions were characterized as hard if ≥50% of the lumen was occluded with calcium or collagen (as determined by MR image characteristics) in the hardest cross section within the lesion. The primary outcome was the time it took to cross a guidewire through the target lesion. The secondary outcome was the need for stenting.

RESULTS

Of 14 lesions, 8 (57%) were defined as hard and 6 (43%) were soft on the basis of MR image characteristics. Hard lesions took significantly longer to cross than soft lesions (average, 14 minutes 49 seconds vs 2 minutes 17 seconds; P = .003). Hard lesions also required stenting more often than soft lesions (Fisher exact test, P = .008). Of 14 lesions, 2 (14%) could not be crossed with a guidewire, and both lesions were hard. MR images also detected occult patencies and noncalcified hard lesions that could not be seen on X-ray angiography.

CONCLUSIONS

MRI can be used to determine which peripheral arterial lesions are more difficult to cross with a guidewire. Future work will determine whether MRI lesion characterization can predict long-term endovascular outcomes to aid in procedure planning.

Endovascular treatment of iliac and common femoral arteries disease by the transradial access: A prospective, feasibility study

AIM

To report feasibility and safety of endovascular interventions on iliac and common femoral arteries, using the transradial access (TRA).

METHODS

100 consecutive patients (19 women; mean age 71, range 37-90years) with critical limb ischemia (30%) or claudication, and TASC A-D lesions in iliac or common femoral arteries, were prospectively enrolled, from January 2013 to June 2015, to be treated via the TRA. Exclusion criteria included no palpable radial arteries (RA) and the presence of a fistula for hemodialysis. Patients were evaluated for procedural technical success, in-hospital complications, and 30days clinical success (defined as improvement of at least one grade in the Rutherford classification of symptoms).

RESULTS

A total of 131 iliac and common femoral arteries lesions were treated (58 in common iliac arteries, 38 in external iliac arteries and 35 in common femoral arteries). Ninety-two stents were deployed in 58 patients. Procedural technical success was achieved in 91% of the lesions; with 95% technical success rate in common iliac arteries, 87% in external iliac arteries and 89% in common femoral arteries; with 72% technical success rate in occlusions and 98% in stenosis. No in-hospital complications were observed. At 30days, 93 patients (93%) had an improvement of at least one category in the Rutherford classification of symptoms (clinical success rate 93%); 12 patients (12%) had an asymptomatic occlusion of the RA.

CONCLUSIONS

TRA can be used to treat iliac and common femoral arteries lesions with a high grade of technical success and a low rate of complications.

Lower extremity computed tomography angiography can help predict technical success of endovascular revascularization in the superficial femoral and popliteal artery

OBJECTIVE

Preprocedural computed tomography angiography (CTA) assists in evaluating vascular morphology and disease distribution and in treatment planning for patients with lower extremity peripheral artery disease (PAD). The aim of the study was to determine the predictive value of radiographic findings on CTA and technical success of endovascular revascularization of occlusions in the superficial femoral artery-popliteal (SFA-pop) region.

METHODS

Medical records and available imaging studies were reviewed for patients undergoing endovascular intervention for PAD between January 2013 and December 2015 at a single academic institution. Radiologists reviewed preoperative CTA scans of patients with occlusions in the SFA-pop region. Radiographic criteria previously used to evaluate chronic occlusions in the coronary arteries were used. Technical success, defined as restoration of inline flow through the SFA-pop region with <30% stenosis at the end of the procedure, and intraoperative details were evaluated.

RESULTS

From 2013 to 2015, there were 407 patients who underwent 540 endovascular procedures for PAD. Preprocedural CTA scans were performed in 217 patients (53.3%), and 84 occlusions in the SFA-pop region were diagnosed. Ten occlusions were excluded as no endovascular attempt to cross the lesion was made because of extensive disease or concomitant iliac intervention. Of the remaining 74 occlusions in the SFA-pop region, 59 were successfully treated (80%) and 15 were unsuccessfully crossed (20%). The indications for revascularization were claudication in 57% of patients and critical limb ischemia in the remaining patients. TransAtlantic Inter-Society Consensus A, B, and C occlusions were treated with 87% success, whereas D occlusions were treated with 68% success (P = .047). There were nine occlusions with 100% vessel calcification that was associated with technical failure (P = .014). Longer lengths of occlusion were also associated with technical failure (P = .042). Multiple occlusions (P = .55), negative remodeling (P = .69), vessel runoff (P = .56), and percentage of vessel calcification (P = .059) were not associated with failure. On multivariable analysis, 100% calcification remained the only significant predictor of technical failure (odds ratio, 9.0; 95% confidence interval, 1.8-45.8; P = .008).

CONCLUSIONS

Analysis of preoperative CTA shows 100% calcification as the best predictor of technical failure of endovascular revascularization of occlusions in the SFA-pop region. Further studies are needed to determine the cost-effectiveness of obtaining preoperative CTA for lower extremity PAD.

Percutaneous Therapies for Peripheral Artery Disease

Percutaneous therapies for peripheral artery disease continue to evolve with new techniques and devices. Although guidelines-recommended therapies have impacted cardiovascular morbidity and mortality, endovascular interventions have been shown to reduce limb pain, improve quality of life, and prolong walking distance for those with claudication and to reduce amputation rates among those with critical limb ischemia. Novel devices such as drug-eluting stents and drug-coated balloons have improved patency for moderate-length lesions, whereas others allow treatment of heavily calcified and tortuous segments. New adjunctive devices to cross lesions and reduce or modify associated plaque have also been developed, although level 1 data regarding their efficacy are sparse. There has also been a better mechanistic understanding of lower extremity endovascular treatment using tools such as intravascular ultrasound. This information has highlighted the need for better stent size selection for the femoropopliteal arterial segments and larger balloon diameters for the tibial arteries. Moreover, a wound perfusion approach with direct in-line flow, the so-called angiosome approach, and reconstruction of the pedal loop have been advocated for improved wound healing. Technical advances such as the tibiopedal access and reentry methods have allowed crossing of lesions that were considered no option for the endovascular approach in the past. Collectively, there has been increased awareness, interest, and commitment by various specialty societies and organizations to advance the treatment of peripheral artery disease and critical limb ischemia. This is also evident by the recent coalition of 7 professional societies and organizations that represented >150 000 allied health professionals and millions of patients with peripheral artery disease at the 2015 Centers for Medicaid and Medicare Services Medicare Evidence Development and Coverage Analysis Committee meeting. The percutaneous therapies for peripheral artery disease continue to evolve with longer follow-up with randomized data and larger prospective registries. In the future, it is hopeful that we will treat the lower extremity arteries according to segments, taking into account plaque morphology, luminal versus subintimal crossing, location, and stenotic versus occlusive disease. Until then, we must identify the most cost-effective, efficacious, and safe treatment for each patient. The goal of this article is to aid the practicing vascular specialist consider the optimal choices for the management of patients with vascular disease.

Gene-based therapies in patients with critical limb ischemia

Critical limb ischemia (CLI) constitutes a life-limiting and life-threatening disease. Revascularization, either endovascular or surgical, remains the best treatment option accompanied by medication and risk factor modification. Patients unable to undergo revascularization, referred as 'no-option patients', have been the center of interest the last few years, subjected to treatment therapies based on proteins (mainly growth factors) involved in angiogenesis via gene delivery to the ischemic tissue. Areas covered: This review focuses on these growth factors, gives an update of the studies available, discusses the possible problems that influence outcomes and describes future perspectives including possible new technologies that will improve them. Additionally, the authors attempt to place therapeutic angiogenesis to the bigger frame of tailored therapy in CLI. Expert opinion: Although encouraging in the beginning, growth factor therapy results have been equivocal and inconclusive. And while it would be misleading to approach gene therapy as panacea, its effect on the micro-circulatory level activating angiogenesis and arteriogenesis could act as an important adjunct in personalized treatment.