Retrospective Evaluation of the Effect of Lumbar Sympathetic Blockade on Pain Scores, Fontaine Classification, and Collateral Perfusion Status in Patients with Lower Extremity Peripheral Arterial Disease.

Background and Objectives: The aim of this retrospective study was to evaluate the effect of lumbar sympathetic block (LSB) on pain scores, Fontaine Classification, and collateral perfusion status in patients with lower extremity peripheral artery disease (PAD), in whom revascularization is impossible. Material and Methods: Medical records of 21 patients with PAD who underwent LSB with a combination of local anesthetics, steroids, and patient follow-up forms containing six-month follow-ups between January 2020 and March 2021 were retrospectively reviewed. Numeric Rating Scale (NRS), Pain Detect Questionnaire (PDQ) scores, Fontaine Classification Stages, and collateral perfusion status (collateral diameter and/or development of neovascularization) evaluated by arterial color Doppler Ultrasound (US) from the medical records and follow-up forms of the patients were reviewed. Results: NRS and PDQ scores were significantly lower, and regression of the Fontaine Classification Stages was significantly better after the procedure at the first, third, and sixth month than at the baseline values (p < 0.001). Only four patients (19%) had collaterals before the procedure. An increase in the collateral diameter after LSB was noted in three out of four patients. Before the procedure, 17 patients had no prominent collateral. However, in thirteen of these patients, after LSB, neovascularization was detected during the six-month follow-up period (three patients in the first month, seven patients in the third month, and thirteen patients in the sixth month). The number of patients evolving neovascularization after LSB was found to be statistically significant at the third and sixth months compared to the initial examination (p < 0.001). Conclusions: LSB with the use of local anesthetic and steroids in patients with lower extremity PAD not only led to lower NRS and PDQ scores, but also resulted in regressed Fontaine Classification Stages and better collateral perfusion status.

Multiple instance learning detects peripheral arterial disease from high-resolution color fundus photography.

Peripheral arterial disease (PAD) is caused by atherosclerosis and is a common disease of the elderly leading to excess morbidity and mortality. Early PAD diagnosis is important, as the only available causal therapy is addressing risk factors like smoking, hypercholesterolemia or hypertension. However, current diagnostic techniques often do not detect early stages of PAD. We theorize that PAD's underlying cause atherosclerosis can be detected on color fundus photography (CFP) images with a convolutional neural network architecture, which might aid earlier PAD diagnosis and improve disease monitoring. In this explorative study a deep attention-based Multiple Instance Learning (MIL) architecture is used to capture retinal imaging biomarkers on CFP images of 135 examinations. To capture subtle variations in vascular structures, higher image resolution can be utilized by partitioning the CFP into patches. Our architecture converts each patch into a feature vector, and determines its relative importance via an automatically computed attention weight. Our best model achieves an ROC AUC score of 0.890. Visualizing these attention weights provides insights about the network's decision and suggests ocular involvement in PAD. Statistical analysis confirms that the optic disc and the temporal arcades are weighted significantly higher (p < 0.001) than retinal background. Our results support the feasibility of detecting the presence of PAD with a modern deep learning approach.

Machine learning for detection of stenoses and aneurysms: application in a physiologically realistic virtual patient database.

This study presents an application of machine learning (ML) methods for detecting the presence of stenoses and aneurysms in the human arterial system. Four major forms of arterial disease-carotid artery stenosis (CAS), subclavian artery stenosis (SAS), peripheral arterial disease (PAD), and abdominal aortic aneurysms (AAA)-are considered. The ML methods are trained and tested on a physiologically realistic virtual patient database (VPD) containing 28,868 healthy subjects, adapted from the authors previous work and augmented to include disease. It is found that the tree-based methods of Random Forest and Gradient Boosting outperform other approaches. The performance of ML methods is quantified through the [Formula: see text] score and computation of sensitivities and specificities. When using six haemodynamic measurements (pressure in the common carotid, brachial, and radial arteries; and flow-rate in the common carotid, brachial, and femoral arteries), it is found that maximum [Formula: see text] scores larger than 0.9 are achieved for CAS and PAD, larger than 0.85 for SAS, and larger than 0.98 for both low- and high-severity AAAs. Corresponding sensitivities and specificities are larger than 90% for CAS and PAD, larger than 85% for SAS, and larger than 98% for both low- and high-severity AAAs. When reducing the number of measurements, performance is degraded by less than 5% when three measurements are used, and less than 10% when only two measurements are used for classification. For AAA, it is shown that [Formula: see text] scores larger than 0.85 and corresponding sensitivities and specificities larger than 85% are achievable when using only a single measurement. The results are encouraging to pursue AAA monitoring and screening through wearable devices which can reliably measure pressure or flow-rates.

GLASS (Global Limb Anatomic Staging System): a critical appraisal.

BACKGROUND: THE Global Vascular Guidelines (GVGs) propose a new Global Anatomic Staging System (GLASS) resulting in three stages of complexity for intervention. The aim of this study was to retrospectively classify a large cohort of CLTI patients according to the GLASS, evaluating its distribution in a real-world setting. METHODS: Retrospective, single center, observational study enrolling all consecutive CLTI patients submitted to infra-inguinal endovascular revascularization in our institution, between June 2014 and September 2019. Patients were categorized according to the GLASS for femoro-popliteal (FP), infra-popliteal (IP) and infra-malleolar grading. FP and IP grades were merged to get the final GLASS stage for each limb. RESULTS: The study included 1995 CLTI patients who underwent 2850 endovascular procedures in which 6009 arterial lesions were successfully treated. The FP segment was classified as: 1292 (45.3%) grade 0, 475 (16.6%) grade 1, 159 (5.6%) grade 2, 209 (7.4%) grade 3, and 715 (25.1%) grade 4. The IP segment was classified as: 1529 (53.6%) grade 0, 183 (6.4%) grade 1, 80 (2.8%) grade 2, 207 (7.3%) grade 3, and 851 (29.9%) grade 4. The combination of FP and IP grading led to GLASS stages: 922 (32.3%) stage 1, 375 (13.2%) stage 2, 1472 (51.6%) stage 3. CONCLUSIONS: The distribution of the FP, IP and final GLASS grading was mainly grouped at the two extremes, letting the intermediate grades rather scarce. The majority of patients present with an absent or severely diseased pedal arch, stressing the need to incorporate infra-malleolar disease into the GLASS.

In silico analysis of the molecular regulatory networks in peripheral arterial occlusive disease.

BACKGROUND: Peripheral arterial occlusive disease (PAOD) is a global public health concern that decreases the quality of life of the patients and can lead to disabilities and death. The aim of this study was to identify the genes and pathways associated with PAOD pathogenesis, and the potential therapeutic targets. METHODS: Differentially expressed genes (DEGs) and miRNAs related to PAOD were extracted from the GSE57691 dataset and through text mining. Additionally, bioinformatics analysis was applied to explore gene ontology, pathways and protein-protein interaction of those DEGs. The potential miRNAs targeting the DEGs and the transcription factors (TFs) regulating miRNAs were predicted by multiple different databases. RESULTS: A total of 59 DEGs were identified, which were significantly enriched in the inflammatory response, immune response, chemokine-mediated signaling pathway and JAK-STAT signaling pathway. Thirteen genes including IL6, CXCL12, IL1B, and STAT3 were hub genes in protein-protein interaction network. In addition, 513 miRNA-target gene pairs were identified, of which CXCL12 and PTPN11 were the potential targets of miRNA-143, and IL1B of miRNA-21. STAT3 was differentially expressed and regulated 27 potential target miRNAs including miRNA-143 and miRNA-21 in TF-miRNA regulatory network. CONCLUSION: In summary, inflammation, immune response and STAT3-mediated miRNA-target genes axis play an important role in PAOD development and progression.

2017 ACC/AHA blood pressure classification and incident peripheral artery disease: The Atherosclerosis Risk in Communities (ARIC) Study.

AIMS: The aim of this study was to evaluate the associations of blood pressure categorization based on the 2017 American College of Cardiology and American Heart Association guideline with the risk of peripheral artery disease (PAD). METHODS: Among 13,113 middle-aged participants, we investigated the associations of 2017 blood pressure categories (systolic <120 and diastolic <80 mmHg (normal if no anti-hypertensive medications; reference), 120-129 and <80 (elevated), 130-139 and/or 80-89 (stage 1 hypertension), and ≥140 and/or ≥90 (stage 2 hypertension)) with incident PAD (hospitalizations with a diagnosis or leg revascularization) using Cox regression models. Analyses were separately conducted in individuals with and without anti-hypertensive medications. RESULTS: During a median follow-up of 25.4 years, 466 incident PAD occurred (271 cases in 9858 participants without anti-hypertensive medications). In participants without anti-hypertensive medications, we observed significant hazard ratios of PAD in elevated blood pressure (1.80 (1.28-2.51)) and stage 2 hypertension (2.40 (1.72-3.34)), but not in stage 1 hypertension. Analyzing systolic and diastolic blood pressure separately, higher systolic blood pressure categories showed significant associations with incident PAD in a graded fashion whereas, for diastolic blood pressure, only ≥90 mmHg did. Generally similar patterns were seen among participants on anti-hypertensive medication, while they had higher risk of PAD than those without at each blood pressure category. CONCLUSIONS: Systolic blood pressure, including the category of 130-139 mmHg, showed stronger associations with incident PAD than did diastolic blood pressure. Consequently, elevated blood pressure conferred similar or even greater risk of PAD than stage 1 hypertension, with implications on how to interpret new blood pressure categories in terms of leg vascular health.

Impact of chronic obstructive pulmonary disease on the outcomes of patients with peripheral artery disease.

BACKGROUND: Peripheral artery disease (PAD) and chronic obstructive pulmonary disease (COPD) are both related with high in-hospital mortality. We aimed to investigate the impact of COPD on the in-hospital outcomes in PAD. METHODS: PAD patients were selected based on ICD-code I70.2 of the German nationwide database, stratified for COPD and compared regarding adverse in-hospital outcomes. RESULTS: Between 01/2005-12/2015, 5,611,827 inpatients (64.8% males) were diagnosed with PAD; of those, 13.6% were coded additionally with COPD. Overall, 277,894 PAD patients (5.0%) died during in-hospital course. Prevalence of cardiovascular diseases as well as cancer (12.1% vs. 7.0%, P < 0.001) was higher in PAD patients with COPD compared to PAD patients without COPD. PAD patients with COPD showed more often lower PAD stages according to Fontaine classification (PAD stage I: 27.1% vs. 19.3%, P < 0.001; PAD stage IIa: 34.9% vs. 35.5%, P < 0.001; PAD stage IIb: 14.5% vs. 13.6%, P < 0.001; PAD stage III: 11.8% vs. 14.8%, P < 0.001; PAD stage IV: 13.8% vs. 19.6%, P < 0.001). The all-cause in-hospital mortality was significantly higher in PAD patients with COPD compared to those without COPD (6.5% vs. 4.7%, P < 0.001). Cardiovascular events comprising pulmonary embolism and myocardial infarction occurred more often in coprevalence with PAD and COPD. COPD was an independent predictor of in-hospital death (OR 1.16 (95%CI 1.15-1.17) P < 0.001) and an independent predictor for pulmonary embolism (PE, OR 1.44 (1.40-1.49), P < 0.001) in PAD patients. CONCLUSION: COPD was associated with a high in-hospital mortality in PAD patients probably driven by higher frequencies of PE and cancer.

Guideline-Oriented Therapy of Lower Extremity Peripheral Artery Disease (PAD) - Current Data and Perspectives. / Leitliniengerechte Therapie der PAVK ­ Aktuelle Studienlage und Ausblick.

BACKGROUND: Because of the demographic change, lower extremity peripheral artery disease (PAD) is becoming increasingly relevant with respect to health economics. PAD patients often suffer from multiple diseases. Consequently, therapy is commonly complex and requires an interdisciplinary approach. Because of rapid technical developments, interventional endovascular therapy regimens play an increasingly important role. METHOD: Review and literature search on the basis of the current German S3 guidelines on the therapy of PAD as well as international guidelines. In terms of state-of-the-art therapies, relevant current studies were considered. RESULTS: Knowledge of existing guidelines and recommendations as well as new therapeutic approaches is essential for the adequate therapy of PAD patients. A close cooperation between the interventional radiologist and the vascular surgeon is the key to success. In addition to established conservative approaches and invasive bypass surgery, the endovascular approach has been a mainstay in the TASC A and B environment for years. It has recently shown promising results in advanced PAD conditions, such as TASC C and D. An endovascular-first strategy is defined in most guidelines. CONCLUSION: A primarily endovascular-first strategy has become the standard in the majority of even complex lesions of the lower extremity arterial system. Regarding the crural segment, a decrease in mortality compared to bypass surgery has been demonstrated. Further evidence can be expected from ongoing randomized multicenter trials. KEY POINTS: · Adequate diagnostic examination is essential for the classification and strategy of therapy in PAD. · Therapeutic decisions are ideally made in an interdisciplinary conference. · Interventional therapy of intermittent claudication after exhaustion of conservative and medicamentous therapy. · Endovascular-first approach in supra- and infrainguinal lesions. · Additional evidence expected from future randomized trials. CITATION FORMAT: · Kersting J, Kamper L, Das M et al. Guideline-Oriented Therapy of Lower Extremity Peripheral Artery Disease (PAD) - Current Data and Perspectives. Fortschr Röntgenstr 2019; 191: 311 - 322.

Updated Clinical and Radiological Classification of Lower Limb Atherosclerotic Disease.

Lower limb atherosclerotic disease has classically been classified as acute or chronic; however, this is an evolving process that has a wide spectrum of clinical and imaging aspects. Owing to the evolvement of endovascular and imaging techniques, we have now garnered new information regarding the pathophysiology and behavior of atherosclerotic disease, also in response to endovascular and surgical techniques. Clinical presentation can actually be classified according to the time of presentation, ranging from acute (<2 weeks) and subacute (from 2 weeks to 3 months) to chronic (over 3 months) and acute/subacute on underlying chronic disease. Imaging characteristics such as the presence of thrombus, number of collaterals, and target vessel wall features may help in defining the correct type of atherosclerotic lesion, triggering the appropriate treatment strategy. Clinical and imaging characteristics of those different stages are complex and not systematically addressed by current guidelines, that do not show any specific recommendations for imaging pathways/characteristics or treatment. This review illustrates the clinical and imaging characteristics of the different stages of lower limb atherosclerotic disease and related treatment options.

Prognostic value of the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification in patients with no-option chronic limb-threatening ischemia.

OBJECTIVE: The Wound, Ischemia, and foot Infection (WIfI) classification was developed to assess amputation risk and hence to aid in clinical decision-making in patients with chronic limb-threatening ischemia (CLTI). WIfI has been validated in multiple CLTI cohorts worldwide. In this study, we examined the relationship between WIfI stage and clinical outcomes in a well-defined subpopulation of CLTI patients considered not eligible for conventional revascularization. The aim of this study was to assess the prognostic value of the WIfI classification for clinical outcomes in a "no-option" CLTI population. METHODS: The Rejuvenating Endothelial Progenitor Cells via Transcutaneous Intra-arterial Supplementation (JUVENTAS) trial was a single-center, double-blinded, randomized placebo-controlled trial studying the effects of autologous bone marrow mononuclear cells in no-option CLTI patients (N = 160). We conducted a retrospective analysis incorporating baseline and follow-up data from the JUVENTAS trial. All wounds were photographed and described at the start and end of the trial to allow WIfI staging. Two independent researchers retrospectively classified all limbs according to the WIfI scheme, which was then related to prospectively collected trial data. Outcomes including wound healing, clinical improvement, minor and major amputation rate, amputation-free survival, and mortality were assessed using Kaplan-Meier analyses. RESULTS: Of the 160 patients, 150 could be included in this study. Most patients had been classified as Rutherford stage 4 (34%) and stage 5 (61%), with corresponding WIfI stage 2 (33%), stage 3 (21%), or stage 4 (35%). Diabetes, impaired renal function, and ankle-brachial index were independently associated with WIfI stage. On univariate analysis, WIfI stage was strongly associated with wound healing (P = .001), improvement of Rutherford stage (P = .009), amputation rate (P < .001), and long-term mortality (median follow-up, 21.1 months; P = .025). Of note, WIfI stage 2 patients had a worse 6-month major amputation rate compared with stage 3. Of the seven amputated stage 2 patients, six were in WIfI category W0-I3-fI0 and scored a maximum grade 3 on ischemia. Reclassification of ischemic rest pain (W0-I3-fI0) to stage 3 improved and reordered the discrimination of outcomes by WIfI stage in this cohort. CONCLUSIONS: This is the first study to demonstrate that WIfI classification is associated with important clinical outcomes in a no-option CLTI population. Our data suggest that limb prognosis is poor in patients with classic ischemic rest pain, without wounds or infection (W0-I3-fI0), when they lack revascularization options. Further studies are needed to determine whether reassignment of this population from WIfI stage 2 to WIfI stage 3 may be appropriate to reflect amputation risk in the absence of successful revascularization for patients suffering from ischemic rest pain in general.

The Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification system predicts wound healing better than direct angiosome perfusion in diabetic foot wounds.

OBJECTIVE: Previous studies show conflicting results in wound healing outcomes based on angiosome direct perfusion (DP), but few have adjusted for wound characteristics in their analyses. We have previously shown that the Society for Vascular Surgery Wound, Ischemia, and foot Infection (WIfI) classification correlates with wound healing in diabetic foot ulcers (DFUs) treated by a multidisciplinary team. The aim of this study was to compare WIfI classification vs DP and pedal arch patency as predictors of wound healing in patients presenting with DFU and peripheral arterial disease. METHODS: We performed a retrospective review of a prospectively maintained database of all patients with peripheral arterial disease presenting to our multidisciplinary DFU clinic who underwent angiography. An angiosome was considered directly perfused if the artery feeding the angiosome was revascularized or was completely patent. Wound healing time at 1 year was compared on the basis of DP vs indirect perfusion, Rutherford pedal arch grade, and WIfI classification using univariable statistics and Cox proportional hazards models. RESULTS: Angiography was performed on 225 wounds in 99 patients (mean age, 63.3 ± 1.2 years; 62.6% male; 53.5% black) during the entire study period. There were 33 WIfI stage 1, 33 stage 2, 51 stage 3, and 108 stage 4 wounds. DP was achieved in 154 wounds (68.4%) and indirect perfusion in 71 wounds (31.6%). On univariable analysis, WIfI classification was significantly associated with improved wound healing (57.2% for WIfI 3/4 vs 77.3% for WIfI 1/2; P = .02), whereas DP and pedal arch patency were not (both, P ≥ .08). After adjusting for baseline patient and wound characteristics, WIfI stage remained independently predictive of wound healing (WIfI 3/4: hazard ratio [HR], 0.77; 95% confidence interval [CI], 0.67-0.88), whereas DP (HR, 0.82; 95% CI, 0.55-1.21) and pedal arch grade (HR, 0.85; 95% CI, 0.70-1.03) were not. CONCLUSIONS: In our population of patients treated by a multidisciplinary diabetic foot service, the Society for Vascular Surgery WIfI classification system was a stronger predictor of diabetic foot wound healing than DP or pedal arch patency. Our results suggest that a measure of wound severity should be included in all future studies assessing wound healing as an outcome, as differences in patients' wound characteristics may be a strong contributor to the variation of angiosome-directed perfusion results previously observed.

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.

Importance of postprocedural Wound, Ischemia, and foot Infection (WIfI) restaging in predicting limb salvage.

OBJECTIVE: The Wound, Ischemia, and foot Infection (WIfI) classification system was created to encompass demographic changes and expanding techniques of revascularization to perform meaningful analyses of outcomes in the treatment of the threatened limb. The WIfI index is intended to be analogous to the TNM staging system for cancer, with restaging to be done after control of infection and after revascularization. Our goal was to evaluate the effectiveness of WIfI restaging after therapy in the prediction of limb outcomes. METHODS: Preoperative WIfI scoring was performed prospectively for all critical limb ischemia patients who underwent revascularization from January 2014 to June 2015. WIfI restaging and assessment of outcomes were performed retrospectively through August 2016. WIfI classification was determined at the following intervals: preoperatively, immediately postoperatively, and 1 month and 6 months after intervention. Amputation-free survival (AFS) was the primary end point. Kaplan-Meier plot analysis and comparisons of preoperative grades with respective postoperative grades were performed using paired t-test, χ2 test, and correlation analyses. RESULTS: A total of 180 limbs and 172 critical limb ischemia patients underwent revascularization, of which 29 limbs had major amputations (16%). Wound grades generally improved after surgery across the entire cohort. Major amputation was associated with preoperative wound grade and remained associated with wound grade at postoperative restaging at 1 month and beyond on the basis of amputation frequency analysis (preoperatively, 1 month, and 6 months, P = .03, < .001, and < .001, respectively). Wound grade was significantly associated with AFS at 1 month and 6 months after intervention (log-rank, P < .001 for restaging intervals). Ischemia grades improved initially with a slight decline across the cohort at 6 months. Ischemia grade at 1 month postoperatively was associated with AFS (log-rank, P = .03). Foot infection grades also improved at each time interval. Foot infection grade was associated with AFS at 1 month postoperatively (log-rank, P < .001) and at 6 months (log-rank, P = .017). CONCLUSIONS: WIfI restaging is an important tool for predicting limb loss and assessing adequacy of intervention, more so than baseline WIfI alone. The 1- and 6-month postoperative ischemia grade correlated with AFS, whereas preoperative grade did not. The 1- and 6-month postoperative wound and foot infection grades additionally correlated with AFS. WIfI restaging at 1 month and 6 months postoperatively may help identify a cohort that remains at higher risk for limb loss and may merit more expeditious reintervention.

High-resolution and accelerated multi-parametric mapping with automated characterization of vessel disease using intravascular MRI.

BACKGROUND: Atherosclerosis is prevalent in cardiovascular disease, but present imaging modalities have limited capabilities for characterizing lesion stage, progression and response to intervention. This study tests whether intravascular magnetic resonance imaging (IVMRI) measures of relaxation times (T1, T2) and proton density (PD) in a clinical 3 Tesla scanner could characterize vessel disease, and evaluates a practical strategy for accelerated quantification. METHODS: IVMRI was performed in fresh human artery segments and swine vessels in vivo, using fast multi-parametric sequences, 1-2 mm diameter loopless antennae and 200-300 µm resolution. T1, T2 and PD data were used to train a machine learning classifier (support vector machine, SVM) to automatically classify normal vessel, and early or advanced disease, using histology for validation. Disease identification using the SVM was tested with receiver operating characteristic curves. To expedite acquisition of T1, T2 and PD data for vessel characterization, the linear algebraic method ('SLAM') was modified to accommodate the antenna's highly-nonuniform sensitivity, and used to provide average T1, T2 and PD measurements from compartments of normal and pathological tissue segmented from high-resolution images at acceleration factors of R ≤ 18-fold. The results were validated using compartment-average measures derived from the high-resolution scans. RESULTS: The SVM accurately classified ~80% of samples into the three disease classes. The 'area-under-the-curve' was 0.96 for detecting disease in 248 samples, with T1 providing the best discrimination. SLAM T1, T2 and PD measures for R ≤ 10 were indistinguishable from the true means of segmented tissue compartments. CONCLUSION: High-resolution IVMRI measures of T1, T2 and PD with a trained SVM can automatically classify normal, early and advanced atherosclerosis with high sensitivity and specificity. Replacing relaxometric MRI with SLAM yields good estimates of T1, T2 and PD an order-of-magnitude faster to facilitate IVMRI-based characterization of vessel disease.

Peripheral Artery Disease: What You Need to Know.

Synopsis Claudication from peripheral artery disease (PAD) may mimic or coexist with musculoskeletal conditions and represents an important diagnostic consideration in patients over 50 years of age. Physical therapists are optimally positioned to recognize this condition by incorporating a vascular history and physical examination in appropriately selected patients. Recognition of PAD is important both from the standpoint of addressing the ischemic risk to the limb and because PAD is associated with high cerebrovascular and cardiovascular risk. Therefore, multidisciplinary management of patients with PAD is essential. Extensive evidence supports treatment of PAD-related claudication with supervised exercise, and physical therapists are well positioned to play an important role in this treatment. J Orthop Sports Phys Ther 2017;47(12):957-964. Epub 9 Oct 2017. doi:10.2519/jospt.2017.7442.

Angiographic classification of patterns of restenosis following femoropopliteal artery intervention: A proposed scoring system.

OBJECTIVES: To propose a classification system for characterizing angiographic femoropopliteal artery restenosis patterns associated with common endovascular modalities. BACKGROUND: Peripheral artery disease is a worldwide issue affecting millions of people. Despite a myriad of endovascular technologies available to treat peripheral artery disease of the femoropopliteal arteries, restenosis remains a common failure mode. Characterizing common patterns of restenosis is important to discern the potential impact of baseline patient, lesion, and procedural characteristics, as well as treatment modalities on either the primary success or the failure patterns associated with restenosis. METHODS: Studies included in the analysis were from previous core laboratory-adjudicated femoropopliteal artery disease trials and registries reflecting a wide array of treatment modalities. RESULTS: From the subjects enrolled and analyzed, there were 403 total angiograms for analysis and adjudication. Target lesion revascularization images of the 32 validation cases were evaluated for index treated length, diameter stenosis, and lesion morphology characteristics. The following lesion types are proposed: Type 1 "Focal" pattern, which may be "Edge Proximal" or "Edge Distal" depending on location; a Type 2 "Multifocal" pattern which may also exhibit edge restenosis, but may also be "Edge Bilateral"; a Type 3 "Moderate" pattern and a Type 4 "Diffuse" pattern; and finally, a Type 5 "Occlusion". CONCLUSIONS: A classification system that enables healthcare professionals to anticipate and describe failures following the index procedure, thereby impacting the choice of options for retreatment, may facilitate consistency and standardization within the heterogeneous field of endovascular device treatments for the femoropopliteal artery.

Managing claudication in the community setting.

Advances made in medical management and treatment options in addressing lower extremity claudication and vascular disease have skyrocketed during the last decade. Given the recent advances in treatment options, there is often the perception within the medical community and general community that to get the most "cutting edge" treatment, one must go to an academic center or practitioner. The goal of this portion of the discussion is to explore the question of what differences in treatment options there are between a community practice and an academic practice within those members of the vascular surgery specialty. Are there really any differences in the types of treatments offered or availability of the different modalities, and what drives us as practitioners to one over the other?

Statement for Doppler waveforms analysis.

Peripheral artery disease of the lower limbs (PAD) is a common disease. Evaluation of PAD is primarily based on non-invasive examinations with analysis of the arterial Doppler signal being a key element. However, the description of arterial Doppler waveforms morphologies varies considerably across medical schools and from country to country. In order to overcome this issue, the French College of Teachers for Vascular Medicine (Collège des Enseignants de Médecine Vasculaire; CEMV) has summarised the published data on Doppler waveforms analysis and proposes a new "Saint-Bonnet" classification system to describe Doppler waveforms morphologies. The simplified Saint-Bonnet classification comprises eight types and allows taking into account if the Doppler signal does not revert to baseline. This classification, which is based on previous classifications, could improve the descriptions of both physiological and pathological waveforms, recorded in lower limb arteries. According to the reviewed literature, recommendations about the use of Doppler waveforms are proposed. This statement is a preamble to reach an international consensus on the subject, which would standardize the description of arterial waveforms and improve the management of PAD patients.

Mining peripheral arterial disease cases from narrative clinical notes using natural language processing.

OBJECTIVE: Lower extremity peripheral arterial disease (PAD) is highly prevalent and affects millions of individuals worldwide. We developed a natural language processing (NLP) system for automated ascertainment of PAD cases from clinical narrative notes and compared the performance of the NLP algorithm with billing code algorithms, using ankle-brachial index test results as the gold standard. METHODS: We compared the performance of the NLP algorithm to (1) results of gold standard ankle-brachial index; (2) previously validated algorithms based on relevant International Classification of Diseases, Ninth Revision diagnostic codes (simple model); and (3) a combination of International Classification of Diseases, Ninth Revision codes with procedural codes (full model). A dataset of 1569 patients with PAD and controls was randomly divided into training (n = 935) and testing (n = 634) subsets. RESULTS: We iteratively refined the NLP algorithm in the training set including narrative note sections, note types, and service types, to maximize its accuracy. In the testing dataset, when compared with both simple and full models, the NLP algorithm had better accuracy (NLP, 91.8%; full model, 81.8%; simple model, 83%; P < .001), positive predictive value (NLP, 92.9%; full model, 74.3%; simple model, 79.9%; P < .001), and specificity (NLP, 92.5%; full model, 64.2%; simple model, 75.9%; P < .001). CONCLUSIONS: A knowledge-driven NLP algorithm for automatic ascertainment of PAD cases from clinical notes had greater accuracy than billing code algorithms. Our findings highlight the potential of NLP tools for rapid and efficient ascertainment of PAD cases from electronic health records to facilitate clinical investigation and eventually improve care by clinical decision support.