Validation of MRI assessment of foot perfusion for improving treatment of patients with peripheral artery disease.

INTRODUCTION: Information on tissue perfusion in the foot is important when treating patients with chronic limb-threatening ischemia. This study aims to test the reliability of different magnetic resonance sequences when measuring perfusion in the foot. METHODS: Sixteen healthy volunteers had their right foot scanned in a test/retest study with six different magnetic resonance sequences (BOLD, multi-echo gradient echo (mGRE), 2D and 3D pCASL, PASL FAIR, and DWI with intravoxel incoherent motion (IVIM) with quantitative measurements of perfusion. For five sequences, cuff-induced ischemia followed by a hyperactive response was measured. Images of the feet were segmented into angiosomes and perfusion data were extracted from the five angiosomes. RESULTS: BOLD, PASL FAIR, mGRE, and DWI with IVIM had low mean differences between the first and second scans, while the results of 2D and 3D pCASL had the highest differences. Based on a paired t-test, BOLD, and FAIR were able to distinguish between perfusion and no perfusion in all angiosomes with p-values below 0.01. This was not the case with 2D and 3D pCASL with p-values above 0.05 in all angiosomes. The mGRE could not distinguish between perfusion and no perfusion in the lateral side of the foot. CONCLUSION: BOLD, mGRE, pASL FAIR, and DWI with IVIM seem to give more robust results compared to 2D and 3D pCASL. Further studies on patients with peripheral artery disease should explore if the sequences can have clinical relevance when assessing tissue ischemia and results of revascularization. IMPLICATIONS FOR PRACTICE: This study provides knowledge that could be used to improve the diagnosis of patient with chronic limb-threatening ischemia to explore tissue perfusion.

Evaluation of short-term mortality in patients with Medicare undergoing endovascular interventions for chronic limb-threatening ischemia.

INTRODUCTION: Patients with chronic limb-threatening ischemia (CLTI) have high mortality rates after revascularization. Risk stratification for short-term outcomes is challenging. We aimed to develop machine-learning models to rank predictive variables for 30-day and 90-day all-cause mortality after peripheral vascular intervention (PVI). METHODS: Patients undergoing PVI for CLTI in the Medicare-linked Vascular Quality Initiative were included. Sixty-six preprocedural variables were included. Random survival forest (RSF) models were constructed for 30-day and 90-day all-cause mortality in the training sample and evaluated in the testing sample. Predictive variables were ranked based on the frequency that they caused branch splitting nearest the root node by importance-weighted relative importance plots. Model performance was assessed by the Brier score, continuous ranked probability score, out-of-bag error rate, and Harrell's C-index. RESULTS: A total of 10,114 patients were included. The crude mortality rate was 4.4% at 30 days and 10.6% at 90 days. RSF models commonly identified stage 5 chronic kidney disease (CKD), dementia, congestive heart failure (CHF), age, urgent procedures, and need for assisted care as the most predictive variables. For both models, eight of the top 10 variables were either medical comorbidities or functional status variables. Models showed good discrimination (C-statistic 0.72 and 0.73) and calibration (Brier score 0.03 and 0.10). CONCLUSION: RSF models for 30-day and 90-day all-cause mortality commonly identified CKD, dementia, CHF, need for assisted care at home, urgent procedures, and age as the most predictive variables as critical factors in CLTI. Results may help guide individualized risk-benefit treatment conversations regarding PVI.

Association between sex and long-term outcomes of endovascular treatment for peripheral artery disease.

BACKGROUND: Endovascular peripheral vascular intervention (PVI) has become the primary revascularization technique used for peripheral artery disease (PAD). Yet, there is limited understanding of long-term outcomes of PVI among women versus men. In this study, our objective was to investigate sex differences in the long-term outcomes of patients undergoing PVI. METHODS: We performed a cohort study of patients undergoing PVI for PAD from January 1, 2010 to September 30, 2015 using data in the Vascular Quality Initiative (VQI) registry. Patients were linked to fee-for-service Medicare claims to identify late outcomes including major amputation, reintervention, major adverse limb event (major amputation or reintervention [MALE]), and mortality. Sex differences in outcomes were evaluated using cumulative incidence curves, Gray's test, and mixed effects Cox proportional hazards regression accounting for patient and lesion characteristics using inverse probability weighted estimates. RESULTS: In this cohort of 15,437 patients, 44% (n = 6731) were women. Women were less likely to present with claudication than men (45% vs. 49%, p < 0.001, absolute standardized difference, d = 0.08) or be able to ambulate independently (ambulatory: 70% vs. 76%, p < 0.001, d = 0.14). There were no major sex differences in lesion characteristics, except for an increased frequency of tibial artery treatment in men (23% vs. 18% in women, p < 0.001, d = 0.12). Among patients with claudication, women had a higher risk-adjusted rate of major amputation (hazard ratio [HR] = 1.72, 95% confidence interval [CI]: 1.18-2.49), but a lower risk of mortality (HR = 0.86, 95% CI: 0.75-0.99). There were no sex differences in reintervention or MALE for patients with claudication. However, among patients with chronic limb-threatening ischemia, women had a lower risk-adjusted hazard of major amputation (HR = 0.79, 95% CI: 0.67-0.93), MALE (HR = 0.86, 95% CI: 0.78-0.96), and mortality (HR = 0.86, 95% CI: 0.79-0.94). CONCLUSION: There is significant heterogeneity in PVI outcomes among men and women, especially after stratifying by symptom severity. A lower overall mortality in women with claudication was accompanied by a higher risk of major amputation. Men with chronic limb-threatening ischemia had a higher risk of major amputation, MALE, and mortality. Developing sex-specific approaches to PVI that prioritizes limb outcomes in women can improve the quality of vascular care for men and women.

Assessment of chronic limb threatening ischemia using thermal imaging.

OBJECTIVES: Current chronic limb threatening ischemia (CLTI) diagnostics require expensive equipment, using ionizing radiation or contrast agents, or summative surrogate methods lacking in spatial information. Our aim is to develop and improve contactless, non-ionizing and cost-effective diagnostic methods for CLTI assessment with high spatial accuracy by utilizing dynamic thermal imaging and the angiosome concept. APPROACH: Dynamic thermal imaging test protocol was suggested and implemented with a number of computational parameters. Pilot data was measured from 3 healthy young subjects, 4 peripheral artery disease (PAD) patients and 4 CLTI patients. The protocol consists of clinical reference measurements, including ankle- and toe-brachial indices (ABI, TBI), and a modified patient bed for hydrostatic and thermal modulation tests. The data was analyzed using bivariate correlation. RESULTS: The thermal recovery time constant was on average higher for the PAD (88%) and CLTI (83%) groups with respect to the healthy young subjects. The contralateral symmetry was high for the healthy young group and low for the CLTI group. The recovery time constants showed high negative correlation to TBI (ρ = -0.73) and ABI (ρ = -0.60). The relation of these clinical parameters to the hydrostatic response and absolute temperatures (|ρ|<0.3) remained unclear. CONCLUSION: The lack of correlation for absolute temperatures or their contralateral differences with the clinical status, ABI and TBI disputes their use in CLTI diagnostics. Thermal modulation tests tend to augment the signs of thermoregulation deficiencies and accordingly high correlations were found with all reference metrics. The method is promising for establishing the connection between impaired perfusion and thermography. The hydrostatic modulation test requires more research with stricter test conditions.

Mangled Extremity Severity Score in the Assessment of Extremity Injuries - Is it Reliable?

The mangled extremity severity score (MESS) was established 28 years ago to decide performing an amputation in cases of limb trauma. It assigns points for 4 aspects of the injury: the extent of soft tissue and skeletal injury, limb ischemia and ischemic duration, shock, and age. A score of 7 or higher indicates that primary amputation is required. Thirty-one patients with MESS scores of 7 to 8 underwent limb salvage surgeries, with 13 limbs being saved and 18 limbs being amputated. Upper extremities trauma had a salvage rate of 62.5%, whereas lower extremity trauma had a salvage rate of 20%. MESS is not a sensitive predictor of amputation in upper limb trauma, but it is useful in lower limb injuries.

COVID-19-related Peripheral Arterial Thrombosis Treated in a Large Health Maintenance Organization.

BACKGROUND: COVID-19 was initially identified as an acute respiratory disease, but it was quickly recognized that multiple organ systems could be affected. Venous thrombosis and pulmonary embolism have been well reported. However, there is a paucity of data on COVID-19-related arterial thrombosis. We examined the incidence, characteristics, treatment, and outcome in patients with acute COVID-19-related arterial thrombosis in a large health maintenance organization (HMO). METHODS: A retrospective multicenter case review was performed from March 2020 to March 2021. Cases were identified through a questionnaire sent to vascular surgeons. Patient characteristics, imaging, treatment, and outcome were reviewed. Successful revascularization was defined as restoration of blood flow with viability of the end organ and absence of death within 30 days. Limb salvage was defined as prevention of major amputation (transtibial or transfemoral) and absence of death in 30 days. RESULTS: There were 37,845 patients admitted with COVID-19 complications during this time. Among this group, 26 patients (0.07%) had COVID-19-related arterial thrombosis. The mean age was 61.7 years (range, 33-82 years) with 20 men (77%) and 6 women (23%). Ethnic minorities comprised 25 of 26 cases (96%). Peripheral arterial disease (PAD) was present in 4 of 26 (15%), active smoking in 1 of 26 (3.8%), and diabetes in 19 of 26 (73%) cases. Most patients developed acute arterial ischemia in the outpatient setting, 20 of 26 (77%). Of the outpatients, 6 of 20 (30%) had asymptomatic COVID-19 and 14 of 20 (70%) had only mild upper respiratory symptoms. Distribution of ischemia was as follows: 23 patients had at least one lower extremity ischemia, one patient had cerebral and lower extremity, one had mesenteric and lower extremity, and one had upper extremity ischemia. Revascularization was attempted in 21 patients, of which 12 of 21 (57%) were successful. Limb salvage was successful in 13 of 26 (50%) patients. The overall mortality was 31% (8/26). CONCLUSIONS: Our experience in a large HMO revealed that the incidence of COVID-19-related arterial thrombosis was low. The actual incidence is likely to be higher since our method of case collection was incomplete. The majority of arterial thrombosis occurred in the outpatient setting in patients with asymptomatic or mild/moderate COVID-19 respiratory disease. Acute ischemia was the inciting factor for hospitalization in these cases. Acute lower extremity ischemia was the most common presentation, and limb salvage rate was lower than that expected when compared to ischemia related to PAD. Arterial thrombosis associated with COVID-19 portends a significantly higher mortality. Education of primary care providers is paramount to prevent delayed diagnosis as most patients initially developed ischemia in the outpatient setting and did not have a high cardiovascular risk profile.

Outcomes of Endovascular-First Versus Bypass-First Approach for Patients With Chronic Limb-Threatening Ischemia Using a Medicare-Linked Database.

BACKGROUND: Chronic limb-threatening ischemia (CLTI) has been increasing in prevalence and remains a significant cause of limb loss and disability and a strong predictor of cardiovascular mortality. Previous studies have demonstrated that endovascular and open repair are similarly effective. These findings led to a significant increase in the adoption of the less-invasive endovascular-first (EVF) approach. However, it remains unknown whether the 2 treatment modalities have similar durability in today's real-world setting. The aim of the present study was to compare the midterm outcomes of the EVF and bypass-first (BF) strategies in patients with CLTI. METHODS: We identified all patients who had undergone limb revascularization from January 2010 to December 2016 in the Vascular Quality Initiative Medicare-linked database. Patients with a history of previous revascularization and those who had undergone hybrid or suprainguinal procedures were excluded from the present study. The remaining patients were divided into 2 groups: EVF and BF. The main end points were 2-year limb salvage, freedom from reintervention, amputation-free survival (AFS), and freedom from all-cause mortality (ACM). RESULTS: The EVF approach was applied to 12,062 patients (70%) and the BF approach to 5,166 patients (30%). The median follow-up was 33 months (interquartile range [IQR]: 14-49). Patients in the EVF group were older and had more comorbidities and tissue loss. At 2 years, the BF group had achieved greater rates of limb salvage (86.4% vs. 82.1%; P < 0.001), freedom from reintervention (72% vs. 68%; P < 0.001), AFS (66.9% vs. 56.3%; P < 0.001), and freedom from ACM (75.7% vs. 66.1%; P < 0.001). After adjusting for potential confounders, an effect of the treatment strategy on limb salvage (adjusted hazard ratio [aHR], 1.03; 95% confidence interval [CI], 0.93-1.16; P = 0.55), reintervention (aHR, 0.95; 95% CI, 0.89-1.019; P = 0.06), AFS (aHR, 0.94; 95% CI, 0.89-1.007; P = 0.08), and ACM (aHR, 0.93; 95% CI, 0.87-1.001; P = 0.055) was not observed. CONCLUSIONS: The present study is the largest real-word analysis showing the noninferiority of the EVF approach in patients with CLTI, with similar limb salvage, durability, AFS, and ACM compared with the BF approach. However, level 1 evidence on the role of the revascularization strategy in these challenging patients is needed.

Assessment of Tissue Viability Following Amputation Surgery Using Near-Infrared Fluorescence Imaging With Indocyanine Green.

BACKGROUND: Patients with chronic limb threatening ischemia have a risk of undergoing a major amputation within 1 year of nearly 30% with a substantial risk of re-amputation since wound healing is often impaired. Quantitative assessment of regional tissue viability following amputation surgery can identify patients at risk for impaired wound healing. In quantification of regional tissue perfusion, near-infrared (NIR) fluorescence imaging using Indocyanine Green (ICG) seems promising. METHODS: This pilot study included adult patients undergoing lower extremity amputation surgery due to peripheral artery disease or diabetes mellitus. ICG NIR fluorescence imaging was performed within 5 days following amputation surgery using the Quest Spectrum PlatformⓇ. Following intravenous administration of ICG, the NIR fluorescence intensity of the amputation wound was recorded for 10 minutes. The NIR fluorescence intensity videos were analyzed and if a fluorescence deficit was observed, this region was marked as "low fluorescence." All other regions were marked as "normal fluorescence." RESULTS: Successful ICG NIR fluorescence imaging was performed in 10 patients undergoing a total of 15 amputations. No "low fluorescence" regions were observed in 11 out of 15 amputation wounds. In 10 out of these 11 amputations, no wound healing problems occurred during follow-up. Regions with "low fluorescence" were observed in 4 amputation wounds. Impaired wound healing corresponding to these regions was observed in all wounds and a re-amputation was necessary in 3 out of 4. When observing time-related parameters, regions with low fluorescence had a significantly longer time to maximum intensity (113 seconds vs. 32 seconds, P = 0.003) and a significantly lesser decline in outflow after five minutes (80.3% vs. 57.0%, P = 0.003). CONCLUSIONS: ICG NIR fluorescence imaging was able to predict postoperative skin necrosis in all four cases. Quantitative assessment of regional perfusion remains challenging due toinfluencing factors on the NIR fluorescence intensity signal, including camera angle, camera distance and ICG dosage. This was also observed in this study, contributing to a large variety in fluorescence intensity parameters among patients. To provide surgeons with reliable NIR fluorescence cut-off values for prediction of wound healing, prospective studies on the intra-operative use of this technique are required. The potential prediction of wound healing using ICG NIR fluorescence imaging will have a huge impact on patient mortality, morbidity as well as the burden of amputation surgery on health care.

Contemporary management of acute and chronic mesenteric ischemia: 10-year experience from a multihospital healthcare system.

OBJECTIVE: Endovascular and hybrid methods have been increasingly used to treat mesenteric ischemia. However, the long-term outcomes and risk of symptom recurrence remain unknown. The objective of the present study was to define the predictors of postoperative morbidity, mortality, and patency loss for acute mesenteric ischemia (AMI) and chronic mesenteric ischemia (CMI). METHODS: The inpatient and follow-up records for all patients who had undergone revascularization for AMI and CMI from 2010 to 2020 at a multicenter hospital system were reviewed. Patency and mortality were evaluated with Cox regression, visualized with Kaplan-Meier curves, and compared using log-rank testing. Patency was further evaluated using Fine-Gray regression with death as a competing risk. The postoperative major adverse events (MAE) and 30-day mortality were evaluated with logistic regression. RESULTS: A total of 407 patients were included, 148 with AMI and 259 with CMI. For the AMI group, the 30-day mortality was 31%. Open surgery was associated with lower rates of bowel resection (odds ratio [OR], 0.23; 95% confidence interval [CI], 0.13-0.61). The etiology of AMI also did not change the outcomes (OR, 1.30; 95% CI, 0.77-2.19). Adjusted analyses indicated that a history of diabetes (OR, 2.77; 95% CI, 1.37-5.61) and sepsis on presentation (OR, 2.32; 95% CI, 1.18-4.58) were independently associated with an increased risk of 30-day MAE. In the CMI group, open surgery and chronic kidney disease were associated with a higher incidence of MAE (OR, 3.03; 95% CI, 1.14-8.05; OR, 2.37; 95% CI, 1.31-4.31). In contrast, chronic kidney disease (OR, 3.02; 95% CI, 1.10-8.37) and inpatient status before revascularization (OR, 2.78; 95% CI, 1.01-7.61) were associated with increased 30-day mortality. For the CMI group, the endovascular cohort had experienced greater rates of symptom recurrence (29% vs 13%) with a faster onset (endovascular, 64 days; vs bypass, 338 days). CONCLUSIONS: AMI remains a morbid disease despite the evolving revascularization techniques. An open approach should remain the reference standard because it reduces the likelihood of bowel resection. For CMI, endovascular interventions have improved the postoperative morbidity but have also resulted in early symptom recurrence and reintervention. An endovascular-first approach should be the standard of care for CMI with close surveillance.

Volume rendered 3D OCTA assessment of macular ischemia in patients with type 1 diabetes and without diabetic retinopathy.

The aim of this study was to measure macular perfusion in patients with type 1 diabetes and no signs of diabetic retinopathy (DR) using volume rendered three-dimensional (3D) optical coherence tomography angiography (OCTA). We collected data from 35 patients with diabetes and no DR who had OCTA obtained. An additional control group of 35 eyes from 35 healthy subjects was included for comparison. OCTA volume data were processed with a previously presented algorithm in order to obtain the 3D vascular volume and 3D perfusion density. In order to weigh the contribution of different plexuses' impairment to volume rendered vascular perfusion, OCTA en face images were binarized in order to obtain two-dimensional (2D) perfusion density metrics. Mean ± SD age was 27.2 ± 10.2 years [range 19-64 years] in the diabetic group and 31.0 ± 11.4 years [range 19-61 years] in the control group (p = 0.145). The 3D vascular volume was 0.27 ± 0.05 mm3 in the diabetic group and 0.29 ± 0.04 mm3 in the control group (p = 0.020). The 3D perfusion density was 9.3 ± 1.6% and 10.3 ± 1.6% in diabetic patients and controls, respectively (p = 0.005). Using a 2D visualization, the perfusion density was lower in diabetic patients, but only at the deep vascular complex (DVC) level (38.9 ± 3.7% in diabetes and 41.0 ± 3.1% in controls, p = 0.001), while no differences were detected at the superficial capillary plexus (SCP) level (34.4 ± 3.1% and 34.3 ± 3.8% in the diabetic and healthy subjects, respectively, p = 0.899). In conclusion, eyes without signs of DR of patients with diabetes have a reduced volume rendered macular perfusion compared to control healthy eyes.

Intraoperative quality assessment of tissue perfusion with indocyanine green (ICG) in a porcine model of mesenteric ischemia.

BACKGROUND: Mesenteric ischemia is a severe and potentially lethal event. Assessment of intestine perfusion is eminently depending on the skills, and the experience of the surgeon. Thus, the therapy is biased by the right evaluation. Aim of this study is to determine the applicability, and the usefulness of fluorescent-imaging (FI) with indocyanine green (ICG) in a porcine model of mesenteric ischemia. Second end-point is the verification of a visual and quantitative assessment tool of the intestinal perfusion. METHODS: In 18 pigs (54,2 ±2,9kg) an occlusion of a side-branch of the mesenteric artery was performed for 3 (group I, n = 7), 6 (group II, n = 7), and 10 hours (group III, n = 4). After reperfusion a 60 minutes observation period was carried out. 3 regions of interest were defined: ischemic bowel (D1), transitional zone (D2), and non-ischemic bowel (D3). ICG-FI was performed during baseline (T0), occlusion (T1), reperfusion (T2) and after an observation period of 60 minutes (T4). RESULTS: All experiments could be finished successfully. ICG-FI was assessed using assessment of background-subtracted peak fluorescence intensity (BSFI), slope of fluorescence intensity (SFI), and a baseline adjusted ratio of both parameters. ICG-FI confirmed loss of perfusion in D1, decreased perfusion in D2, and increased perfusion in D3. After reperfusion ICG-FI increased in group 2 due to a severe tissue damage resulting in a capillary leakage. In group I ICG-FI was equal to baseline values indicating the totally reversible loss of perfusion. CONCLUSION: Using ICG-FI to estimate intestine perfusion after different durations of ischemia is viable using a porcine model of mesenteric ischemia. Even small differences in perfusion can be reliably determined by ICG-FI. Thus, ICG-FI is an encouraging method to evaluate intestine perfusion intraoperatively.

Comparison of femoropopliteal plain balloon angioplasty for chronic limb-threatening ischemia in the BASIL trial and in a UK contemporary series.

BACKGROUND: Since the turn of the millennium, there has been a worldwide trend towards an endovascular-first strategy where possible revascularization strategy for chronic limb-threatening ischemia. There is concern that this may be inappropriate and can result in net patient harm. The aim of this study, therefore, is to compare important clinical outcomes following femoropopliteal plain balloon angioplasty (FP-PBA), with selective use of bare metal stents (BMSs), in a contemporary series (CS) of patients treated in our unit between 2009 and 2014 with those observed following FP-PBA ± BMS in the United Kingdom National Institute of Health Research Health Technology Assessment-funded Bypass vs Angioplasty in Severe Ischaemia of the Leg (BASIL-1 [B1]) trial (treated 1999-2004). METHODS: Baseline and clinical outcome data (amputation-free survival [AFS], overall survival [OS], limb salvage, freedom from reintervention, and freedom from major adverse limb events) were obtained from prospectively gathered hospital data and B1 trial case record forms. RESULTS: There were 237 CS and 218 B1 patients. CS patients were older (77 vs 73 years; P = .0002). B1 patients were more likely to be current smokers, less likely to be on best medical therapy, and underwent more extensive endovascular interventions. CS had more hospital admissions (4 vs 2; P < .0001) before they reached their primary endpoint (AFS). Immediate technical success was nonsignificantly higher in the CS patients (87% vs 83%; P = .2). BMS were used in 20 CS (8%) and 2 B1 (1%) patients (P = .0002). AFS (hazard ratio, 0.64; 95% confidence interval, 0.49-0.82; P = .0005) and OS (hazard ratio, 0.58; 95% confidence interval, 0.44-0.76; P = .0001) were significantly worse in the CS cohort. There was no significant difference in limb salvage, freedom from reintervention, or freedom from major adverse limb events. CONCLUSIONS: Patients with chronic limb-threatening ischemia managed in our unit (2009-2014) by means of a FP-PBA ± BMS first (where possible) revascularization strategy experienced significantly worse AFS and OS than patients treated with FP-PBA ± BMS in the B1 trial 10 years earlier (1999-2004).

Fast-track thrombolysis protocol for acute limb ischemia.

OBJECTIVE: Catheter-directed thrombolysis in the treatment of acute lower extremity arterial occlusions often requires several interventional sessions to generate successful outcomes. It is typically an expensive procedure, necessitating extended hospital length of stay (LOS) that may be associated with an increase in both local and systemic hemorrhagic complications. Five years ago, we created the fast-track thrombolysis protocol for arteries (FTTP-A) to deal with these concerns. The goal of our protocol is to re-establish patency during the first session of thrombolysis, thus decreasing costs and complications associated with prolonged periods of thrombolytic exposure. METHODS: A retrospective study of 42 patients who were treated for acute limb ischemia at our institution by FTTP-A from January 2014 to February 2019 was performed. FTTP-A includes periadventitial lidocaine injection at the arterial puncture site under ultrasound guidance, contrast arteriography of the entire targeted segment, pharmacomechanical rheolytic thrombectomy of the occluded arterial segment, tissue plasminogen activator infusion along the occluded segment, balloon maceration of the thrombus, and (if deemed necessary) placement of a stent in an area of significant (≥30%) stenosis that is refractory to balloon angioplasty and thrombolysis. After the stenosis or thrombus is cleared, patients are prescribed an oral anticoagulant agent. RESULTS: Primary FTTP-A (50 total interventions) was performed in 42 patients. The median age of patients was 67.2 ± 12.2 years (range, 41-98 years), and 54.8% were male; 59.5% of the procedures were performed on the left lower extremity. Initial arterial access was obtained through the common femoral artery in 39 of 42 cases (92.9%); in the remaining 3 cases, it was obtained in a left bypass access site, a right femoral-popliteal graft, and a right femoral-femoral graft. The mean operative time was 148.9 ± 62.9 minutes (range, 83-313 minutes), and the mean volume of tissue plasminogen activator infused was 9.7 ± 4.0 mg (range, 2-20 mg). The median cost including medications and interventional tools was $4673.19 per procedure. The mean postoperative LOS was 3.1 ± 4.5 days (range, 1-25 days). Median postoperative LOS was 1 day. Mean postoperative follow-up was 27 ± 19.2 months (range, 0-62 months). Single-session FTTP-A was successful in 81% (n = 34/42) of patients; the remaining 8 patients (19%) required a single additional session. Of the 42 patients, 34 (81%) required arterial stenting. Periprocedural complications consisted of one patient with hematuria, which resolved, and one patient with thrombocytopenia, which resolved. No patients experienced rethrombosis within 30 days of FTTP-A. During the 5-year study period, there was no significant local or systemic hemorrhage, limb loss, or mortality related to this protocol. CONCLUSIONS: FTTP-A appears to be a safe, efficacious, and cost-effective procedure in the resolution of acute lower extremity arterial occlusions.

Registry Assessment of Peripheral Interventional Devices objective performance goals for superficial femoral and popliteal artery peripheral vascular interventions.

BACKGROUND: The Superficial Femoral Artery-Popliteal EvidencE Development Study Group developed contemporary objective performance goals (OPGs) for peripheral vascular interventions (PVI) for superficial femoral artery (SFA)-popliteal artery disease using the Registry Assessment of Peripheral Interventional Devices. METHODS: The Society for Vascular Surgery Vascular Quality Initiative PVI registry from January 2010 to October 2016 was used to develop OPGs based on SFA-popliteal procedures (n = 21,377) for intermittent claudication and critical limb ischemia (CLI). OPGs included 1-year rates for target lesion revascularization (TLR), major amputation, and 1 and 4-year survival rates. OPGs were calculated for the SFA and popliteal arteries and stratified by four treatments: angioplasty alone (percutaneous transluminal angioplasty [PTA]), self-expanding stenting, atherectomy, and any treatment type. Outcomes were illustrated by unadjusted Kaplan-Meier analyses. RESULTS: Cohorts included PTA (n = 7505), stenting (n = 9217), atherectomy (n = 2510) and any treatment (n = 21,377). The mean age was 69 years, 58% were male, 79% were White, and 52% had CLI. The freedom from TLR OPGs at 1 year in the SFA were 80.3% (PTA), 83.2% (stenting), 83.9% (atherectomy), and 81.9% (any treatments). The freedom from TLR OPGs at 1 year in the popliteal were 81.3% (PTA), 81.3% (stenting), 80.2% (atherectomy), and 81.1% (any treatments). The freedom from major amputation OPGs at 1 year after SFA PVI were 93.4% (PTA), 95.7% (stenting), 95.1% (atherectomy), and 94.8% (any treatments). The freedom from major amputation OPG at 1 year after popliteal PVI were 90.5% (PTA), 93.7% (stenting), 91.8% (atherectomy), and 91.8%, (any treatments). The 4-year survival OPGs after SFA PVI were 76% (PTA), 80% (stenting), 82% (atherectomy), and 79% (any treatments), and for the popliteal artery were 72% (PTA), 77% (stenting), 82% (atherectomy), and 75% (any treatment). On a multivariable analysis, which included patient-level, leg-level, and lesion-level covariates, CLI was the single independent factor associated with increased TLR, amputation, and mortality. CONCLUSIONS: The Superficial Femoral Artery-Popliteal EvidencE Development OPGs define a new, contemporary benchmark for SFA-popliteal interventions using a large subset of real-world evidence to inform more efficient peripheral device clinical trial designs to support regulatory and clinical decision-making. It is appropriate to discuss proposals intended for regulatory approval with the US Food and Drug Administration to refine the OPG to match the specific trial population. The OPGs may be updated using coordinated registry networks to assess long-term real-world device performance.

Assessment of carotid artery stenosis and lower limb peripheral ischemia before coronary artery bypass grafting operations: a non-randomized clinical trial.

BACKGROUND: Atherosclerosis is a systemic disease affecting the coronary, carotid, and lower limb arteries. Cerebrovascular accidents and lower limb ischemia are devastating postoperative complications. We aimed to evaluate the role of non-selective routine arterial duplex scanning in patients undergoing coronary artery bypass grafting (CABG). METHODS: This non-randomized clinical trial included 360 patients scheduled for elective isolated CABG who were divided into two groups: low-risk (n = 180) and high-risk (n = 180). Both groups underwent preoperative carotid and lower limb ultrasound screening for associated arteriopathy. RESULTS: 16 (8.9%) patients and 22 (12.2%) patients showed ≥70% carotid artery stenosis while 11 patients (6.1%) and 20 patients (11.1%) showed ≥50% lower limb arterial stenosis in the low-risk group and the high-risk group, respectively; though the difference was not statistically significant in both the cases (p > 0.1). CONCLUSION: Routine preoperative peripheral arterial screening by sonography is a feasible and effective strategy to avoid unnecessary post CABG complications. TRIAL REGISTRATION: NCT03516929 , Registered in 24 th of April 2018.

Medicare reimbursement of lower extremity bypass does not cover cost of care for most patients with critical limb ischemia.

OBJECTIVE: Lower extremity bypass surgery remains an important treatment option for patients with critical limb ischemia (CLI), but is resource intensive. We sought to evaluate the cost and Medicare reimbursement for lower extremity bypass surgery in patients with CLI. METHODS: Hospital cost accounting systems were queried for total technical and professional costs incurred and reimbursement received for patients with CLI undergoing lower extremity bypass at our center between 2011 and 2017. Patients were identified by assignment to Diagnosis-Related Group (DRG) 252, 253, or 254 (other vascular procedure with major complication/comorbidity, with complication/comorbidity, and without complication/comorbidity, respectively). Additional clinical data were incorporated from the Vascular Quality Initiative clinical registry. For non-Medicare patients, reimbursement was indexed to Medicare rates. Contribution margins (reimbursement minus cost) from technical and professional services were analyzed for each patient and summarized by DRG. We compared technical, professional, and total costs; reimbursement; and contribution margins across DRGs using univariate statistics and evaluated factors associated with total contribution margin using median quantile regression. RESULTS: We analyzed 68 patients with hemodynamically confirmed CLI (46% rest pain, 54% tissue loss), of whom 25% received a prosthetic graft. Mean age was 66.1 ± 11.6 years, 69% were male, 49% diabetic, 44% current smokers, and 4% on dialysis. In general, total infrainguinal bypass cost was adequately compensated for patients assigned only the most complex DRG 252 (median, $2490; interquartile range [IQR], -$1,621 to $10,080). In the majority of patients with less complex DRG 253 (median, -$3,100; IQR, -$8499 to $109) and DRG 254 (median, -$4902; IQR, -$9259 to $1059), reimbursement did not cover the cost of care. Both technical costs and professional costs varied significantly with the complexity of DRG. Although reimbursement from technical services increased alongside increasing complexity of DRG, there was insignificant variation in professional reimbursement as DRG complexity increased. On multivariable modeling, longer length of stay (-$2547 per additional day) and preoperative dialysis (-$5555) were significantly associated with negative margins. CONCLUSIONS: For the majority of patients with CLI, current Medicare reimbursement does not adequately cover the cost of providing care after open bypass surgery. As commercial insurers move toward Medicare reimbursement rates, more granular risk stratification profiles are needed to ensure open surgical care for patients with CLI remains financially sustainable.

Prospective assessment of function and cold-intolerance following revascularization for hypothenar hammer syndrome.

Ulnar artery revascularization in hypothenar hammer syndrome has repeatedly been shown to reduce ischaemic symptoms, however with varying graft patency percentages. This study prospectively assesses the effect of revascularization surgery with a vein graft using validated questionnaires in seven patients. The Disabilities of the Arm, Shoulder and Hand (DASH) and the Cold Intolerance Symptom Severity (CISS) questionnaires have been used to compare the preoperative and postoperative functionality and cold intolerance. All patients showed improvement in either functionality, or cold intolerance, or both from disabled to nearly normalized levels and resumed their occupation at final follow-up (mean of 28 months). Strikingly this was also the case in a patient with graft stenosis. Patients with the highest preoperative questionnaire scores showed most postoperative improvement. In conclusion, revascularization surgery seems to improve the symptomatology irrespective of graft patency. Questionnaires can be a valuable contribution to quantify and to follow the symptomatology in hypothenar hammer syndrome.

Novel ultrasonographic Halo Score for giant cell arteritis: assessment of diagnostic accuracy and association with ocular ischaemia.

OBJECTIVES: Ultrasound of temporal and axillary arteries may reveal vessel wall inflammation in patients with giant cell arteritis (GCA). We developed a ultrasound scoring system to quantify the extent of vascular inflammation and investigated its diagnostic accuracy and association with clinical factors in GCA. METHODS: This is a prospective study including 89 patients suspected of having GCA, of whom 58 had a confirmed clinical diagnosis of GCA after 6 months follow-up. All patients underwent bilateral ultrasound examination of the three temporal artery (TA) segments and axillary arteries, prior to TA biopsy. The extent of vascular inflammation was quantified by (1) counting the number of TA segments and axillary arteries with a halo and (2) calculating a composite Halo Score that also incorporated the thickness of each halo. RESULTS: Halo counts and Halo Scores showed moderate diagnostic accuracy for a clinical diagnosis of GCA. They correlated positively with systemic inflammation. When compared with the halo count, the Halo Score correlated better with C-reactive protein (CRP) levels and allowed to firmly establish the diagnosis of GCA in more patients. Higher halo counts and Halo Scores were associated with a higher risk of ocular ischaemia. They allowed to identify subgroups of patients with low risk (≤5%) and high risk of ocular ischaemia (>30%). CONCLUSIONS: Ultrasound halo scoring allows to quantify the extent of vascular inflammation in GCA. Extensive vascular inflammation on ultrasound may provide strong diagnostic confirmation and associates with ocular ischaemia in GCA.