Anticoagulation in Patients with Premature Peripheral Artery Disease Undergoing Lower Extremity Revascularization.

BACKGROUND: Premature peripheral artery disease (PAD), defined by lower extremity revascularization (LER) at age ≤ 50 years, is associated with poor major adverse limb events. The early onset of disease is thought to be influenced by genetic factors that regulate homeostasis of the vascular wall and coagulation. The aim of this study is to investigate the effect of anticoagulation as an adjunct to antiplatelet therapy on the outcomes of LER in patients with premature PAD. METHODS: There were 8,804 patients with premature PAD on preoperative and postoperative antiplatelet therapy only and 1,236 patients on preoperative and postoperative anticoagulation plus antiplatelet therapy in the Vascular Quality Initiative peripheral vascular intervention, infrainguinal, and suprainguinal files. Propensity score matching (2:1) was performed between patients with premature PAD who were on antiplatelet therapy and those on anticoagulation plus antiplatelet therapy. Perioperative and 1-year outcomes were analyzed including reintervention, major amputation, and mortality. RESULTS: Patients on anticoagulation were more likely to have coronary artery disease (48.7% vs. 41.2%, P < 0.001), congestive heart failure (20.2% vs. 13.1%, P < 0.001), and have undergone prior LER (73.9% vs. 49.2%, P < 0.001) compared to patients on antiplatelet therapy only. They were also less likely to be independently ambulatory (74.2% vs. 81.8%, P < 0.001) and be on a statin medication (66.8% vs. 74.3%, P < 0.001) compared to patients on antiplatelet therapy only. Patients on anticoagulation were also less likely to be treated for claudication (38.1% vs. 48.6%, P < 0.001), and less likely to be treated with an endovascular procedure (64.8% vs. 73.8%, P < 0.001). After matching for baseline characteristics, there were 1,256 patients on antiplatelet therapy only and 628 patients on anticoagulation. Patients on anticoagulation were more likely to require a return to the operating room (3.7% vs. 1.6%, P < 0.001) and had higher perioperative mortality (1.1% vs. 0.3%, P = 0.032), but major amputation was not significantly different (1.8% vs. 1.6%, P = 0.798) compared to patients on antiplatelet therapy alone. At 1 year, amputation-free survival was higher in patients on antiplatelets only compared to patients on anticoagulation and antiplatelet medications (87.5% vs. 80.9%, log-rank P = 0.001). CONCLUSIONS: Anticoagulation in addition to antiplatelet therapy in patients with premature PAD undergoing LER is associated with increased reintervention and mortality at 1 year.

The radiographic relationship of the femoral head, inguinal ligament, and common femoral artery bifurcation for optimal vascular access.

Objective: Common femoral artery (CFA) access is commonly used for endovascular interventions. Access site complications contribute to significant morbidity and mortality. This study characterizes the radiographic variability in the relationship of the femoral head, the inguinal ligament, and the CFA bifurcation, to identify the zone of optimal CFA access. Methods: Human cadaver dissection of the inguinal ligament and CFA bifurcation was performed. The inguinal ligament and CFA bifurcation were marked with radiopaque pins and plain anteroposterior radiographs were obtained. Radiographic measurements of the femoral head length, the distance of the top of the femoral head to the inguinal ligament, and to the CFA bifurcation were obtained. Results were reported as percentage of femoral head covered by the inguinal ligament or the CFA bifurcation relative to the top of the femoral head. A heatmap was derived to determine a safe access zone between the inguinal ligament and CFA bifurcation. Results: Forty-five groin dissections (male, n = 20; female, n = 25) were performed in 26 cadavers. The mean overlap of the inguinal ligament with the femoral head was 11.2 mm (range, -19.4 to 27.4 mm). There were no age (<85 vs ≥85 years) or sex-related differences. In 82.6% of cadaveric CFA exposures, there was overlap between the inguinal ligament and femoral head (mean, 27.7%; range, -85.7% to 70.1%), with 55.6% having a >25% overlap. In 11.1%, there was an overlap between the lower one-third of the femoral head and the CFA bifurcation. Cumulatively, heatmap analysis depicted a >80% likelihood of avoiding the inguinal ligament and CFA bifurcation below the midpoint of the femoral head. Conclusions: Significant variability exists in the relationship between the inguinal ligament, CFA bifurcation, and the femoral head, suggesting the lack of a consistently safe access zone. The safest access zone in >80% of patients lies below the radiographic midpoint of the femoral head and the inferior aspect of the femoral head.

Atherectomy - The Options, the Evidence, and When Should It Be Used.

The use of atherectomy for peripheral vascular interventions (PVIs) has increased exponentially and reached 18% of all PVI in the United States. The theoretical benefit on extensive arterial calcification relies on the concept of plaque modification and removal instead of displacement, as with other endovascular techniques. To date, there are no prospective studies comparing the different atherectomy technologies (directional, rotational, orbital, and laser). Moreover, most related prospective comparative studies have a small number of patients, and larger studies are single arm in patients with relatively mild to moderate disease burden. While available literature shows lower dissection risk and reduced bailout stenting, the superiority of this technology compared to other endovascular techniques has yet to be proven. Despite the lack of level 1 evidence to support its superiority, the lucrative reimbursement fueled the overuse of this technology as first-line therapy, particularly in office-based laboratories and ambulatory surgery centers. The use of atherectomy ought to be selective and complementary to other endovascular technologies, and individualized patient-level decision-making based on the practitioner's preference and expertise is essential to selectively incorporate atherectomy in managing complex atherosclerotic lesions.

Comparative Outcomes of Peripheral Vascular Interventions in Patients on Chronic Anticoagulation with Factor Xa Inhibitors and Vitamin K Antagonists.

BACKGROUND: In patients undergoing revascularization for peripheral arterial disease (PAD), low-dose Factor Xa inhibitors (FXaI) taken with aspirin improved limb and cardiovascular outcomes compared to aspirin alone. Furthermore, in atrial fibrillation and venous thromboembolism, FXaI are recommended over vitamin K antagonists (VKA) for chronic anticoagulation. While studies have evaluated different perioperative anticoagulation regimens in patients treated for PAD, the optimal regimen for chronic anticoagulation in patients with PAD undergoing peripheral vascular intervention (PVI) has not been determined. This analysis compares outcomes of patients after PVI that require chronic anticoagulation with FXaI and VKA. METHODS: The Vascular Quality Initiative-PVI database was used. Patients consistently treated with FXaI or VKA before the procedure, at discharge, and on long-term follow-up were defined as those receiving chronic anticoagulation. Patient demographics, procedural details, and perioperative and long-term outcomes were compared between FXaI and VKA groups. RESULTS: A total of 109,268 patients were analyzed, and 6,885 were chronically anticoagulated with FXaI (N = 2,427) or VKA (N = 4,458). Patients anticoagulated with VKA were more frequently males (65.3% vs. 61.0%, P < 0.001) with end-stage renal disease (9.7% vs. 4.6%, P < 0.001) and more likely to be treated for chronic limb-threatening ischemia (58.1% vs. 52.7%, P < 0.001). Rates of hematoma following PVI were significantly higher in patients taking VKA compared to FXaI (3.5% vs. 1.9%, P < 0.001). Multivariable logistic regression analysis showed that VKA were associated with increased perioperative hematoma than FXaI (odds ratio = 1.89 [1.30-2.82]). Compared to patients taking VKA, those receiving FXaI had lower rates of major amputation (6.7% vs. 8.4%, P = 0.020) and mortality (7.6% vs. 15.2%, P ≤ 0.001). Using Kaplan-Meier analysis, patients consistently anticoagulated with FXaI had improved amputation-free survival after PVI. Adjusting for significant patient and procedural characteristics, Cox proportional hazard regression demonstrated that there is an increased risk for major amputation or mortality in patients using VKA compared to FXaI (hazard ratio 1.61, [1.36-1.90]). CONCLUSIONS: Chronic anticoagulation with FXaI as compared to VKA was associated with superior perioperative and long-term outcomes in patients with PAD undergoing PVI. FXaI should be the preferred agents over VKA for chronic anticoagulation in patients with PAD undergoing PVI.

Endovascular treatment of renal vein thrombosis in a young patient with lung transplant.

Spontaneous renal vein thrombosis is a rare entity. A 28-year-old woman with a history of a double-lung transplant was admitted with flank pain and found to have acute kidney injury. A magnetic resonance venogram demonstrated isolated left renal vein thrombosis with extension into the inferior vena cava. Initial management with therapeutic anticoagulation and hydration was unsuccessful. Thus, pharmacochemical thrombectomy was performed. A temporary suprarenal inferior vena cava filter was placed for intraoperative pulmonary prophylaxis. The patient's renal function returned to baseline and remained normal 13 months later. Early incorporation of percutaneous pharmacomechanical thrombectomy can improve renal function when medical therapy alone is unsuccessful.

The Use and Impact of Cilostazol on Patients Undergoing Endovascular Peripheral Interventions.

BACKGROUND: Cilostazol is used for the treatment of intermittent claudication. The impact of cilostazol on the outcomes of peripheral vascular interventions (PVIs) remains controversial. This study assesses the use and impact of cilostazol on patients undergoing PVI for peripheral arterial disease (PAD). METHODS: The Vascular Quality Initiative (VQI) database files for PVI were reviewed. Patients with PAD who underwent PVI for chronic limb threatening-ischemia or claudication were included and divided based on the use of cilostazol preoperatively. After propensity matching for patient demographics and comorbidities, the short-term and long-term outcomes of the 2 groups (preoperative cilostazol use versus no preoperative cilostazol use) were compared. The Kaplan-Meier method was used to determine outcomes. RESULTS: A total of 245,309 patients underwent PVI procedures and 6.6% (N = 16,366) were on cilostazol prior to intervention. Patients that received cilostazol were more likely to be male (62% vs 60%; P < 0.001), White (77% vs. 75%; P < 0.001), and smokers (83% vs. 77%; P < 0.001). They were less likely to have diabetes mellitus (50% vs. 56%; P < 0.001) and congestive heart failure (14% vs. 23%; P < 0.001). Patient on cilostazol were more likely to be treated for claudication (63% vs. 40%, P < 0.001), undergo prior lower extremity revascularization (55% vs. 51%, P < 0.001) and less likely to have undergone prior minor and major amputation (10% vs. 19%; P < 0.001) compared with patients who did not receive cilostazol. After 3:1 propensity matching, there were 50,265 patients included in the analysis with no differences in baseline characteristics. Patients on cilostazol were less likely to develop renal complications and more likely to be discharged home. Patients on cilostazol had significantly lower rates of long-term mortality (11.5% vs. 13.4%, P < 0.001 and major amputation (4.0% vs. 4.7%, P = 0.022). However, there were no significant differences in rates of reintervention, major adverse limb events, or patency after PVI. Amputation-free survival rates were significantly higher for patients on cilostazol, after 4 years of follow up (89% vs. 87%, P = 0.03). CONCLUSIONS: Cilostazol is underutilized in the VQI database and seems to be associated with improved amputation-free survival. Cilostazol therapy should be considered in all patients with PAD who can tolerate it prior to PVI.

Insulin Requirement and Infrainguinal Bypass Outcomes in Patients with Peripheral Arterial Disease.

BACKGROUND: Diabetes mellitus (DM) is a major risk factor for peripheral artery disease. The association of DM with major adverse limb events (MALE) after lower extremity revascularization remains controversial, as patients with diabetes are typically analyzed as a single, homogenous group. Using a large national database, this study examines the impact of insulin use and glycemic control on the outcomes following infrainguinal bypass. The hypothesis is that prevalent insulin therapy and elevated hemoglobin A1c (HbA1c) are associated with an increased risk of MALEs after infrainguinal bypass in patients with DM and could therefore be used for risk stratification. METHODS: The Vascular Quality Initiative database files for infrainguinal bypass (2007-2021) were retrospectively reviewed. Patients with DM undergoing bypass for peripheral artery disease were included. Patients on dialysis or with prior kidney transplantation were excluded. The characteristics and outcomes of patients with insulin-requiring diabetes mellitus (IRDM) were compared to those of patients not requiring insulin (noninsulin-requiring diabetes mellitus [NIRDM]) prior to the bypass procedure. RESULTS: A total of 9,686 patients with DM (56% IRDM) underwent bypass. Patients with IRDM were significantly younger than patients with NIRDM, more likely to be female (P < 0.01), African American (P < 0.01), and Hispanic (P = 0.031), and more likely to have comorbidities and be categorized into American Society of Anesthesiologist classes IV-V. They were more likely to be treated for chronic limb-threatening ischemia (P < 0.001). Patients with IRDM had significantly higher perioperative complications with no difference in perioperative mortality between the 2 groups. Beyond the perioperative period, with a mean follow-up of 427 days, patients with IRDM had significantly lower crude rates of primary patency and higher crude rates of major amputation, MALE, and mortality compared to patients with NIRDM. Regression analyses demonstrated that insulin requirement, but not HbA1c, was independently associated with a higher risk of MALE (hazard ratio = 1.17 [1.06-1.29]) and mortality (hazard ratio = 1.28 [1.16-1.43]). CONCLUSIONS: Insulin requirement, but not HbA1c, is significantly associated with MALEs and survival after infrainguinal bypass in the Vascular Quality Initiative. Stratification of patients with DM based on their prevalent insulin use prior to infrainguinal bypass surgery could improve the prediction of outcomes of peripheral arterial bypass surgery in patients with diabetes.

Systematic review and meta-analysis of the genetics of peripheral arterial disease.

Background: Peripheral artery disease (PAD) impacts more than 200 million people worldwide. The understanding of the genetics of the disease and its clinical implications continue to evolve. This systematic review provides a comprehensive summary of all DNA variants that have been studied in association with the diagnosis and progression of PAD, with a meta-analysis of the ones replicated in the literature. Methods: A systematic review of all studies examining DNA variants associated with the diagnosis and progression of PAD was performed. Candidate gene and genome-wide association studies (GWAS) were included. A meta-analysis of 13 variants derived from earlier smaller candidate gene studies of the diagnosis of PAD was performed. The literature on the progression of PAD was limited, and a meta-analysis was not feasible because of the heterogeneity in the criteria used to characterize it. Results: A total of 231 DNA variants in 112 papers were studied for the association with the diagnosis of PAD. There were significant variations in the definition of PAD and the selection of controls in the various studies. GWAS have established 19 variants associated with the diagnosis of PAD that were replicated in several large patient cohorts. Only variants in intercellular adhesion molecule-1 (rs5498), IL-6 (rs1800795), and hepatic lipase (rs2070895) showed significant association with the diagnosis of PAD. However, these variants were not noted in the published GWAS. Conclusions: Genetic research in the diagnosis of PAD has significant heterogeneity, but recent GWAS have demonstrated variants consistently associated with the disease. More research focusing on the progression of PAD is needed to identify patients at risk of adverse events and develop strategies that would improve their outcomes.

The development of a novel endovascular grasper for challenging inferior vena cava filter retrieval.

OBJECTIVE: Although inferior vena cava (IVC) filters are commonly retrieved using a snare, lateral tilt and fibrosis around struts can complicate the procedure and sometimes require the use of off-label devices. We describe the development of a novel articulating endovascular grasper designed to remove permanent and retrievable IVC filters in any configuration. METHODS: For in vitro testing, the IVC filters were anchored to the inner wall of a flexible tube in a centered or tilted configuration. A high-contrast backlit camera view simulated the two-dimensional fluoroscopy projection during retrieval. The time from the retrieval device introduction into the camera field to complete filter retrieval was measured in seconds. The control experiment involved temporary IVC filter retrieval with a snare. There were four comparative groups: (1) retrievable filter in centered configuration; (2) retrievable filter in tilted configuration; (3) permanent filter in centered configuration; and (4) permanent filter in tilted configuration. Every experiment was repeated five times, with median retrieval time compared with the control group. For in vivo testing in a porcine model, six tilted infrarenal IVC filters were retrieved with grasper via right jugular approach. Comparison analysis between animal and patient procedures was performed for the following variables: total procedure time, the retrieval time, and fluoroscopy time. RESULTS: The in vitro experiments showed comparable retrieval times between the experimental groups 1, 2, and 4 and the control. However, grasper removal of a centered permanent filter (group 3) required significantly less time than in the control (29 vs 79 seconds; P = .009). In the animal model, all IVC filters were retrieved using the grasper with no adverse events. The total procedure time (21.2 vs 43.5 minutes; P = .01) and the fluoroscopy time (4.3 vs 10 minutes; P = .044) were significantly shorter in the animal model compared with the patient group. Moreover, in the patient group, 16.7% of retrievals required advanced endovascular techniques, and one IVC filter could not be retrieved (success rate = 91.7%), whereas all the IVC filters were successfully retrieved in the animal model without the use of additional tools. CONCLUSIONS: The novel endovascular grasper is effective in retrieving different types of IVC filters in different configurations and compared favorably with the snare in the in vitro model. In vivo experiments demonstrated more effective retrieval when compared with matched patient retrievals.

A comparison of below-knee vs above-knee endovenous ablation of varicose veins.

OBJECTIVE: Varicose veins have a significant impact on quality of life and can commonly occur in the thigh and calves. However, there has been no large-scale investigation examining the relationship between anatomic distribution and outcomes after varicose vein treatment. This study sought to compare below-the-knee (BTK) and above-the-knee (ATK) varicose vein treatment outcomes. METHODS: Employing the Vascular Quality Initiative Varicose Vein Registry, 13,731 patients undergoing varicose vein ablation for either BTK or ATK lesions were identified. Outcomes were assessed using patient-reported outcomes (PROs) and the Venous Clinical Severity Score (VCSS). Continuous variables were compared using the t-test, and categorical variables were analyzed using the χ2 test. Multivariable logistic regression was used to estimate the odds of improvement after intervention. The multivariable model controlled for age, gender, race, preoperative VCSS composite score, and history of deep vein thrombosis. RESULTS: Patients who received below-knee treatment had a lower preoperative VCSS composite (7.0 ± 3.3 vs 7.7 ± 3.3; P < .001) and lower PROs composite scores (11.1 ± 6.4 vs 13.0 ± 6.6; P < .001) compared with those of patients receiving above-knee treatment. However, on follow-up, patients receiving below-knee intervention had a higher postoperative VCSS composite score (4.4 ± 3.3 vs 3.9 ± 3.5; P < .001) and PROs composite score (6.1 ± 4.4 vs 5.8 ± 4.5; P = .007), the latter approaching statistical significance. Patients receiving above-knee interventions also demonstrated more improvement in both composite VCSS (3.8 ± 4.0 vs 2.9 ± 3.7; P < .001) and PROs (7.1 ± 6.8 vs 4.8 ± 6.6; P < .001). Multivariable logistic regression analysis similarly revealed that patients receiving above-knee treatment had significantly higher odds of improvement in VCSS composite in both the unadjusted (odds ratio [OR], 1.45; 95% confidence interval [CI], 1.28-1.65; P < .001 and adjusted (OR, 1.31; 95% CI, 1.14-1.50; P < .001) models. Patients receiving above-knee treatment also had a significantly higher odds of reporting improvement in PROs composite in both the unadjusted (OR, 1.85; 95% CI, 1.64-2.11; P < .001) and adjusted (OR, 1.65; 95% CI, 1.45-1.88; P < .001) models. CONCLUSIONS: Treatment region has a significant association with PROs and VCSS composite scores after varicose vein interventions. Preoperatively, there were significant differences in the composite scores of VCSS and PROs with patients receiving BTK treatment exhibiting less severe symptoms. Yet, the association appeared to reverse postoperatively, with those receiving BTK treatments exhibiting worse PROs, worse VCSS composites scores, and less improvement in VCSS composite scores. Therefore, BTK interventions pose a unique challenge compared with ATK interventions in ensuring commensurate clinical improvement after treatment.

Variations and inconsistencies in venous ablation coverage policies between single-state and multistate carriers in the United States.

BACKGROUND: Vein ablation is a common and effective treatment for patients with chronic venous insufficiency. The overuse of vein ablation despite the existence of evidence-based guidelines has resulted in insurance companies developing restrictive policies for coverage that create barriers to appropriate care. This study compares the insurance coverage by single-state carriers (SSCs) and multistate carriers (MSCs), highlighting the variations and inconsistencies in the various policies. METHODS: The American Venous Forum Venous Policy Navigator was reviewed for the various policies available in the United States. The policies were divided into SSCs and MSCs. The characteristics of the policies, including the anatomic and hemodynamic criteria for specific veins, duration of conservative treatment, disease severity, symptoms, and types of procedures covered, were compared between the two groups. SAS, version 9.4 (SAS Institute Inc) was used for statistical analysis. RESULTS: A total of 122 policies were analyzed and divided between SSCs (n = 85; 69.7%) and MSCs (n = 37; 30.3%). A significant variation was found in the size requirement for great saphenous vein ablation. Although 48% of the policies did not specify a size criterion, the remaining policies indicated a minimal size, ranging from 3 to 5.5 mm. However, no significant differences were found between SSCs and MSCs. Similar findings were encountered for the small and anterior accessory saphenous veins. MSCs were more likely to define a saphenous reflux time >500 ms compared with SSCs (81.1% vs 58.8%; P = .04). A significant difference was found between the SSCs and MSCs in the criteria for perforator ablation in terms of size and reflux time. MSCs were significantly more likely to provide coverage for mechanochemical ablation than were SSCs (24.3% vs 8.2%; P = .03). SSCs were more likely to require ≥12 weeks of compression stocking therapy than were MSCs (76.5% vs 48.7%; P = .01). No significant differences were found in the clinical indications between the two groups; however, MSCs were more likely to mention major hemorrhage than were SSCs. CONCLUSIONS: The results of this study highlight the variations in policies for venous ablation, in particular, the striking inconsistencies in size criteria. MSCs were more likely to cover mechanochemical ablation and require a shorter duration of conservative therapy before intervention compared with SSCs. Evidence-based guidance is needed to develop more coherent policies for venous ablation coverage.

Arterial dissection during peripheral vascular interventions.

OBJECTIVE: Arterial dissection (AD) is a known complication of peripheral vascular interventions (PVIs), but its incidence and significance have not been well-characterized. This study examines AD in the Vascular Quality Initiative database for patients treated for peripheral arterial disease. Our hypothesis is that AD is associated with decreased patency and worse limb outcomes. METHODS: The Vascular Quality Initiative PVI registry (2016-2021) was reviewed. Patients were divided based on the presence or absence of reported AD during the procedure. Trend of incidence and management of AD was derived. The characteristics and outcomes of patients with and without AD were compared. The primary endpoint was primary patency. RESULTS: There was a total of 177,790 cases, and 3% had AD. The incidence of AD significantly increased over the study period from 2.4% to 3.6% (P = .007). Endovascular therapy was used to treat AD in 83.7% of cases, 14.5% were treated medically, and only 1.8% required open surgery. Patients with AD were significantly more likely to be female (47.4% vs 39.7%; P < .001). Patient with AD were more likely to have a history of smoking (79.7% vs 77.2%; P < .001), but were significantly less likely to be on dialysis (8.2% vs 9.3%; P < .001) compared with patients without AD. Patients with AD were more likely to have femoropopliteal disease (45.2% vs 38.0%; P < .001) and undergo treatment of more complex disease as denoted by higher mean number of lesions treated (1.95 ± 1.01 vs 1.71 ± 0.89; P < .001), longer occlusion length (8 ± 16 vs 7 ± 15 cm; P < .001), and more severe TransAtlantic Inter-Society Consensus grade (Grade D: 36.2% vs 29.1%; P < .001). The proportion of stenting as a treatment modality was higher in the dissection group (55.4% vs 41.1%; P < .001). After a mean follow-up of 828 days, patients with AD had significantly lower primary patency than patients without AD. Kaplan-Meier curves demonstrated that the AD group had lower primary patency (86.9% vs 91%; P < .001) and reintervention-free survival (79.5 % vs 84.1%; P < .001) at 1 year with difference in amputation-free survival. Cox proportional hazard regression confirmed the independent association of AD with primary patency and reintervention-free survival. CONCLUSIONS: AD is more common in women and is more likely to occur during treatment of the femoropopliteal segment. AD is associated with decreased primary patency and reintervention-free survival after PVI for peripheral arterial disease.

The Utilization of Protamine during Peripheral Vascular Interventions in the VQI.

BACKGROUND: Protamine administration was shown to reduce bleeding after carotid surgery but the role of protamine during peripheral vascular interventions (PVIs) remains unknown. This study evaluates the trend and outcomes of protamine use in the Vascular Quality Initiative (VQI). Our hypothesis is that the use of protamine is associated with decreased bleeding after PVI. METHODS: Patients undergoing elective PVI in the VQI (2016-2020) for peripheral arterial disease were reviewed and the utilization trend for protamine was described. The characteristics of patients undergoing PVI with and without protamine use were compared. After propensity score matching based on the patient's comorbidities, access site, and procedural characteristics, the perioperative outcomes of both groups were compared using multivariable Poisson regression to estimate adjusted rate ratios (aRRs) and 95% confidence intervals (95% CIs). RESULTS: The total number of patients was 131,618 and patients who received protamine constituted 29.8% of the sample (N = 38,191). After propensity matching, the total number of patients was 94,582, and patients who received protamine constituted 28.8% of the sample (N = 27,275). Protamine use significantly increased during the study period from 5.2 to 22.9%. Before propensity score matching, patients who received protamine were more likely to be white (79% vs. 76.8, P ≤ 0.001), smokers (80.5% vs. 78.5%, P ≤ 0.001), with medical comorbidities including hypertension (88.9% vs. 88.5%, P = 0.074), congestive heart failure (20.5% vs. 19.8%, P = 0.006), and chronic obstructive pulmonary disease (28.2% vs. 26.5%). They were also more likely to be on perioperative medications such as P2Y12 inhibitors (44.3% vs. 45, P = 0.013%) and statin (77.4% vs. 76.5%, P = 0.001) compared to patients who did not receive protamine. After propensity matching, there were no significant differences between the 2 groups. There was a significant decrease in bleeding during procedures where protamine was administered compared to no protamine (2.0% vs. 2.2%) (aRR, 0.89 [95% CI 0.80, 0.98]). Protamine was more likely to be given in procedures complicated by perforation (0.8% vs. 0.5%) (aRR, 1.48 [95% CI 1.24, 1.76]) and less likely to be given during procedures with distal embolization (0.4% vs. 0.7%) (aRR, 0.59 [95% CI 0.49, 0.73]). However, patients receiving protamine had significantly higher cardiac complications (1.4% vs. 1.1%) (aRR, 1.27 [95% CI 1.12, 1.43]). There was no significant difference in mortality between the 2 groups. CONCLUSIONS: Protamine use is associated with decreased perioperative bleeding but increased cardiac complications. Protamine should be selectively administered to patients at high risk of bleeding during PVI.

The Impact of Ejection Fraction on Major Adverse Limb Events after Lower Extremity Revascularization.

BACKGROUND: Peripheral arterial disease (PAD) is commonly associated with coronary artery disease, and echocardiography is frequently performed before lower extremity revascularization (LER). However, the incidence of various echocardiographic findings in patients with PAD and their impact on the outcomes of LER has not been well studied. Reduced ejection fraction (EF) ≤ 40% is associated with increased major adverse limb events (MALE) after LER. METHODS: The electronic medical records of patients undergoing LER in a single center were reviewed. Patients were divided based on the presence or absence of reduced EF. Patient, transthoracic echocardiogram, procedural characteristics, and outcomes were compared between the 2 groups. RESULTS: A total of 1,114 patients (N = 131, 11.8% with reduced EF) underwent LER between 2013 and 2019. Patients with reduced EF were more likely to be male and have a history of coronary artery disease and heart failure. Furthermore, they were more likely to have diastolic dysfunction with moderate to severe mitral and tricuspid valve regurgitation. Patients with reduced EF were more likely to undergo LER for chronic limb-threatening ischemia, and to be treated with endovascular procedures. Perioperatively, patients with reduced EF were more likely to develop myocardial infarction. Lastly, the 2 groups had no difference in overall MALE or major amputation. However, on Kaplan-Meier curves, MALE-free survival was significantly lower for patients with reduced EF. Regression analysis demonstrated that indication and not EF was associated with MALE and MALE-free survival. CONCLUSIONS: Reduced EF is associated with decreased MALE-free survival for patients with PAD undergoing LER.

What are the benefits and drawbacks of statins in carotid artery disease? A perspective review.

INTRODUCTION: The prevalence of carotid artery stenosis in the general population is approximately 3%, but approximately 20% among people with acute ischemic stroke. Statins are recommended by multiple international guidelines as the drug of choice for lipid control in people with asymptomatic or symptomatic carotid artery stenosis due to their lipid-lowering and other pleiotropic effects. AREAS COVERED: This review discusses the guidelines for statin usage as a cornerstone in the prevention and management of atherosclerotic carotid artery disease and the impact of statins on stroke incidence and mortality. Statin side effects, alternative therapy, and genetic polymorphisms are reviewed. EXPERT OPINION: Statin therapy is associated with a decreased incidence of stroke and mortality as well as improved outcomes for patients treated with carotid revascularization. Statins are a safe and effective class of medications, but the initiation of therapy warrants close monitoring to avoid rare and potentially serious side effects. Lack of clinical efficacy or the presence of side effects suggests a need for treatment with an alternative therapy such as PCSK9 inhibitors. Understanding the interplay between the mechanisms of statins and PCSK9 inhibition therapies will allow optimal benefits while minimizing risks. Future research into genetic polymorphisms may improve patient selection for personalized therapy.

Balloon rupture with eversion during innominate vein angioplasty requiring surgical retrieval.

Balloon rupture during angioplasty can with calcified or recalcitrant lesions. A 61-year-old woman presented with worsening arm and facial swelling. She had a history of left upper extremity thrombolysis and stenting of the innominate vein 6 years prior. Venography showed severe in-stent stenosis. After crossing the lesion, a 12-mm balloon was inflated, which ruptured at nominal pressure. The balloon became stuck and could not be moved over the wire even after retraction of the sheath. A limited surgical cutdown was performed, and the balloon and the wire were removed together. The ruptured balloon part was found to be everted and circumferentially wrapped around the wire, preventing the wire exchange. After cutting the everted portion of the balloon, the catheter was removed without losing wire access. A high-pressure balloon was subsequently used to treat the lesion successfully. Her symptoms had resolved on follow-up, and the stent remained patent after 6 months.

Arm ischemia in a 4-year-old boy with supracondylar fracture of the humerus due to constraining bands over the brachial artery.

Supracondylar humerus fractures are common in children and can compromise the brachial artery in 5% to 15% of cases. A 4-year-old boy with a left supracondylar fracture developed upper extremity ischemia after pinning of the fracture. Computed tomography angiography revealed cutoff of flow in the brachial artery. Intraoperatively, he was found to have bands tethering the artery into the fracture, obstructing the blood flow. The orthopedic pins were removed, and the constraining bands were lysed to free the artery, with reconstitution of flow confirmed by intraoperative angiography. The fracture was reduced and stabilized, and the patient recovered well with normal arterial flow on follow-up ultrasound after 3 months.

Hybrid Revision of Dysfunctional Aneurysmal Arteriovenous Fistulas.

Endovascular therapy has become the first-line treatment for failing hemodialysis arteriovenous fistulas (AVFs). However, open revision remains an important modality for vascular access maintenance and the recommended approach for AVF aneurysms. This case series describes a hybrid approach for aneurysmal access revision. Three patients were referred for second opinion after failure of endovascular therapy to establish a functioning access. The medical history is briefly described to highlight the limitations of endovascular therapy and the technical advantages of the hybrid approach in these clinical scenarios.