Faculty Bibliography

OBJECTIVE:Venous duplex ultrasound (VDUS) is the accepted initial imaging study to rule out lower extremity deep venous thrombosis (DVT). In accordance with the Intersocietal Accreditation Commission (IAC) vascular laboratory policies, many institutions require technicians to additionally assess the asymptomatic contralateral common femoral vein. There is conflicting literature on whether this policy is needed. Therefore, the aim of this study was to investigate the utility of examining the asymptomatic contralateral common femoral vein in patients undergoing a unilateral lower extremity VDUS to rule out DVT by (1) defining the prevalence of DVT in the contralateral asymptomatic limb and (2) identifying risk factors that predispose patients to develop a DVT in the asymptomatic limb. METHODS:and Student's t-tests, respectively. For all tests, a P-value of <0.05 was considered statistically significant. RESULTS:371 patients (170 inpatient vs. 201 outpatient) with unilateral DVT symptoms who underwent VDUS during the study period were identified. Right leg symptoms were present in 186 (50%) patients and left leg symptoms were present in 185 (50%) patients. The overall incidence of acute DVT in the symptomatic limb was 17% (17.4% outpatient vs. 16.5% inpatient, p=NS). Outpatients were more likely to have superficial venous thrombosis (7.0% vs. 0.6%, p=0.002) and chronic venous changes (25.4% vs. 1.2%, p<0.001) in the symptomatic limb. 59% of DVTs in the symptomatic limb were documented in the calf veins, 25% in the proximal veins, and 16% in both the proximal and calf veins. There were no incidences of bilateral DVT in our cohort. Moreover, none of the patients had a DVT isolated to the contralateral common femoral vein. CONCLUSIONS:Scanning the asymptomatic contralateral common femoral vein may not be necessary for patients undergoing unilateral VDUS for symptomatic DVT, regardless of thrombotic risk factors. A single-extremity study will suffice in most cases, and if implemented, it will improve vascular laboratory efficiency and decrease costs without a decline in DVT detection.

OBJECTIVES/OBJECTIVE:While the use of endovascular intervention for peripheral artery disease (PAD) has expanded in recent years, there remains relatively few studies focused on the endovascular treatment of isolated popliteal artery occlusive disease. The popliteal artery presents a particular challenge for endovascular intervention due to the constant flexion at the knee. We sought to assess the outcomes for endovascular management of isolated popliteal artery occlusive disease based on type of intervention performed. METHODS:The Vascular Qualitative Initiative (VQI) database was queried for patients with isolated popliteal artery occlusive disease who underwent endovascular intervention from January 2011 to December 2019. Patients were excluded from analysis if they did not have Medicare FFS entitlement, had a history of prior intervention in the ipsilateral limb, or had vessels treated in addition to the popliteal artery. Patients were stratified into groups based on their initial presenting symptom (claudication vs. chronic limb threatening ischemia (CLTI)) and were analyzed by endovascular procedure performed (plain old balloon angioplasty (POBA) vs. adjunctive stent/atherectomy). The POBA group underwent only plain balloon angioplasty whereas the adjunctive stent/atherectomy group underwent any type of balloon angioplasty and adjunctive stenting or atherectomy or both. The primary outcome was amputation-free survival, a composite outcome of freedom from major amputation and/or death. RESULTS:A total of 1,740 patients met criteria for analysis who underwent endovascular intervention for isolated popliteal artery occlusive disease. Among patients with claudication, the amputation-free survival rate was significantly higher at 1 year and 3 years for patients treated with adjunctive stent/atherectomy compared to POBA (1 year: 94.2% vs. 88.9%, p = 0.03; 3 years: 83.0% vs. 76.6%, p = 0.04). This difference appeared to be driven by mortality, as mortality was significantly better for adjunctive stent/atherectomy compared to POBA (1 year: 4.6% vs. 10.2%, p = 0.01; 3 years: 15.4% vs. 23.3%, p = 0.02), whereas major amputation rates were not significantly different. However, multivariable analysis showed that use of adjunctive stent/atherectomy was not independently associated with improved amputation-free survival (adjusted HR 0.74, 95% CI 0.48-1.16, p = 0.19). In the CLTI group, amputation-free survival rates were not significantly different for patients treated with adjunctive stent/atherectomy compared to POBA (1 year: 65% vs. 64.6%, p = 0.78; 3 years: 47.1% vs. 42.6%, p = 0.30). Re-intervention rates were not statistically different when stratified by use of adjunctive therapies in either the claudication or CLTI groups. CONCLUSION/CONCLUSIONS:Our results suggest that across all patients with isolated popliteal artery occlusive disease, amputation-free survival rates were comparable regardless of endovascular treatment modality. As expected, amputation-free survival for patients presenting with claudication was favorable compared to those with CLTI, and was driven primarily by mortality. Re-intervention rates were similar across all patients regardless of treatment modality. This study underscores the clinical challenge of treating isolated popliteal artery occlusive disease and stresses the need for further study of adjunctive modalities in treating complex lesions.

OBJECTIVE:Patients with peripheral artery disease (PAD) undergo lower extremity revascularization (LER) for symptomatic relief or limb salvage. Despite LER, patients remain at increased risk of platelet-mediated complications, such as major adverse cardiac and limb events (MACLEs). Platelet activity is associated with cardiovascular events, yet little is known about the dynamic nature of platelet activity over time. We, therefore, investigated the change in platelet activity over time and its association with long-term cardiovascular risk. METHODS:Patients with PAD undergoing LER were enrolled into the multicenter, prospective Platelet Activity and Cardiovascular Events study. Platelet aggregation was assessed by light transmission aggregometry to submaximal epinephrine (0.4 μmol/L) immediately before LER, and on postoperative day 1 or 2 (POD1 or POD2) and 30 (POD30). A hyperreactive platelet phenotype was defined as >60% aggregation. Patients were followed longitudinally for MACLEs, defined as the composite of death, myocardial infarction, stroke, major lower extremity amputation, or acute limb ischemia leading to reintervention. RESULTS:Among 287 patients undergoing LER, the mean age was 70 ± 11 years, 33% were female, 61% were White, and 89% were on baseline antiplatelet therapy. Platelet aggregation to submaximal epinephrine induced a bimodal response; 15.5%, 16.8%, and 16.4% of patients demonstrated a hyperreactive platelet phenotype at baseline, POD1, and POD30, respectively. Platelet aggregation increased by 18.5% (P = .001) from baseline to POD1, which subsequently returned to baseline at POD30. After a median follow-up of 19 months, MACLEs occurred in 165 patients (57%). After adjustment for demographics, clinical risk factors, procedure type, and antiplatelet therapy, platelet hyperreactivity at POD1 was associated with a significant hazard of long-term MACLE (adjusted hazard ratio, 4.61; 95% confidence interval, 2.08-10.20; P < .001). CONCLUSIONS:Among patients with severe PAD, platelet activity increases after LER. Platelet hyperreactivity to submaximal epinephrine on POD1 is associated with long-term MACLE. Platelet activity after LER may represent a modifiable biomarker associated with excess cardiovascular risk.

OBJECTIVES/OBJECTIVE:Total contact casting (TCC) is used to promote wound closure in diabetic foot ulcers (DFUs); however, this technique is underused today. This study aims to further evaluate the efficacy of TCC in a large cohort, including patients with peripheral artery disease (PAD). METHODS:This was a retrospective analysis of patients with DFUs who underwent TCC from 2017 to 2021. PAD was defined as absence of pedal pulse or ABI <0.9. Demographic data, DFU characteristics, and peripheral arterial intervention were evaluated. Outcomes included complete healing, healing time, and rate of major amputation. Subgroup analysis was performed on patients undergoing peripheral intervention. RESULTS:= .0008) compared to patients without intervention. CONCLUSIONS:TCC remains an effective option for treatment of DFUs, as most were completely healed. Patients with PAD may benefit from TCC and revascularization, however, healing rates are lower in this cohort, necessitating the need for close observation.

OBJECTIVE:Vascular surgeons are often called upon to provide emergent surgical assistance to other specialties for iatrogenic complications, both intraoperatively and in the inpatient setting. The management of iatrogenic vascular injury remains a critical role of the vascular surgeon, especially in the context of the increasing adoption of percutaneous procedures by other specialties. This study aims to characterize consultation timing, management, and outcomes for iatrogenic vascular injuries. METHODS:This study identified patients for whom vascular surgery was consulted for iatrogenic vascular complications from February 1, 2022, to May 12, 2023. Patient information, including demographic information, injury details, and details of any operative intervention, was retrospectively collected from February 1, 2022, to October 13, 2022, and prospectively collected for the remainder of the study period. Analyses were performed with R (version 2022.02.03). RESULTS:There were 87 patients with consultations related to iatrogenic vascular injury. Of these, 42 (46%) were female and the mean age was 59 years (±18 years). The most common consulting services were cardiology (32%), cardiothoracic surgery (26%), general surgery (8%), and neurointerventional radiology (10%). Reasons for consultation included hemorrhage (36%), limb ischemia (36%), and treatment of pseudoaneurysm (23%). A total of 24% of consults were intraoperative, 20% of consults related to extracorporeal membrane oxygenation cannulation, and 16% of consults related to ventricular assist devices including left ventricular assist device and intra-aortic balloon pump. The majority of these consult requests (60%) occurred during evening and night hours (5 PM to 7 AM). Emergent intervention was required in 62% of cases and consisted of primary open surgical repair of arterial injury (54%), endovascular intervention (21%), and open thromboembolectomy (15%). Overall, in-hospital mortality for the patient cohort was 20% and the reintervention rate was 23%, reflecting the underlying complexity of the illness and nature of the vascular injury in this patient group. CONCLUSIONS:Vascular surgeons play an essential role in managing emergent life-threatening hemorrhagic and ischemic iatrogenic vascular complications in the hospitalized setting. The complications require immediate bedside or intraoperative consult and often emergent open surgical or endovascular intervention. Furthermore, many of these require urgent management in the evening or overnight hours, and therefore the high frequency of these events represents a potential significant resource utilization and workforce issue to the vascular surgery workforce.

OBJECTIVE:The objective of this study was to investigate the administrative and clinical impacts of prior authorization (PA) processes in the Office-Based Laboratory (OBL) setting. METHODS:This single-institution retrospective analysis studied all OBL PAs pursued between January 2018 and March 2022. Case, PA, and coding information was obtained from the practice's scheduling database. RESULTS:Over the study period, 1,854 OBL cases were scheduled; 8% (n=146) required PA. Of these, 75% (n=110) were for lower extremity arterial interventions, 19% (n=27) were for deep venous interventions, and 6% (n=9) were for other interventions. Of 146 PAs, 19% (n=27) were initially denied but 74.1% (n=7) of these were overturned on appeal. Deep venous procedures were initially denied, at 43.8% (n=14) more often than were arterial procedures, at 11.8% (n=13). Of 146 requested procedures, 4% (n=6) were delayed due to pending prior authorization determination by a mean 14.2±18.3 working days. An additional 6% (n=8) of procedures were performed in the interest of time prior to final determination. Of the 7 terminally denied procedures, 57% (n=4) were performed at cost to the practice based on clinical judgment. CONCLUSIONS:Utilizing prior authorization appeals mechanisms, while administratively onerous, resulted in the overturning of most initial denials.

OBJECTIVE:Endovenous ablation is the standard of care for patients with symptomatic superficial venous insufficiency. For patients with a history of deep vein thrombosis (DVT), concern exists for an increased risk of postprocedural complications, particularly venous thromboembolism. The objective of this study was to evaluate the safety and efficacy of endovenous thermal ablation in patients with a history of DVT. METHODS:The national Vascular Quality Initiative Varicose Vein Registry was queried for superficial venous procedures performed from January 2014 to July 2021. Limbs treated with radiofrequency or laser ablation were compared between patients with and without a DVT history. The primary safety end point was incident DVT or endothermal heat-induced thrombosis (EHIT) II-IV in the treated limb at <3 months of follow-up. The secondary safety end points included any proximal thrombus extension (ie, EHIT I-IV), major bleeding, hematoma, pulmonary embolism, and death due to the procedure. The primary efficacy end point was technical failure (ie, recanalization at <1 week of follow-up). Secondary efficacy end points included the risk of recanalization over time and the postprocedural change in quality-of-life measures. Outcomes stratified by preoperative use of anticoagulation (AC) were also compared among those with prior DVT. RESULTS:Among 33,892 endovenous thermal ablations performed on 23,572 individual patients aged 13 to 90 years, 1698 patients (7.2%) had a history of DVT. Patients with prior DVT were older (P < .001), had a higher body mass index (P < .001), were more likely to be male at birth (P < .001) and Black/African American (P < .001), and had greater CEAP classifications (P < .001). A history of DVT conferred a higher risk of new DVT (1.4% vs 0.8%; P = .03), proximal thrombus extension (2.3% vs 1.6%; P = .045), and bleeding (0.2% vs 0.04%; P = .03). EHIT II-IV, pulmonary embolism, and hematoma risk did not differ by DVT history (P = NS). No deaths from treatment occurred in either group. Continuing preoperative AC in patients with prior DVT did not change the risk of any complications after endovenous ablation (P = NS) but did confer an increased hematoma risk among all endovenous thermal ablations and surgeries (P = .001). Technical failure was similar between groups (2.0% vs 1.2%; P = .07), although a history of DVT conferred an increased recanalization risk over time (hazard ratio, 1.90; 95% confidence interval, 1.46, 2.46; P < .001). The groups had comparable improvements in postprocedural venous clinical severity scores and Heaviness, Aching, Swelling, Throbbing, and Itching scores (P = NS). CONCLUSIONS:Endovenous thermal ablation for patients with a history of DVT was effective. However, appropriate patient counseling regarding a heightened DVT risk, albeit still low, is critical. The decision to continue or withhold AC preoperatively should be tailored on a case-by-case basis.

OBJECTIVES/OBJECTIVE:Though splenic artery aneurysms (SAAs) are the most common visceral aneurysm, there is a paucity of literature on the behavior of these entities. The objective of this study was to review the natural history of patients with SAA. METHODS:This single-institution retrospective analysis studied patients with SAA diagnosed by CT imaging between 2015 and 2019, identified by our institutional radiology database. Imaging, demographic, and clinical data was obtained via the electronic medical record. The growth rate was calculated for patients with radiologic follow-up. RESULTS:The cohort consisted of 853 patients with 890 SAA, of which 692 were female (81.2%). There were 37 women (5.3%) of childbearing age (15-50 years). Mean age at diagnosis was 70.9 years (range: 28-100) years. Frequently observed medical comorbidities included hypertension (70.2%), hypercholesterolemia (54.7%), and prior smoking (32.2%). Imaging indications included abdominal pain (37.3%), unrelated follow-up (28.0%) and follow-up of a previously noted visceral artery aneurysm (8.6%). The mean diameter at diagnosis was 13.3±6.3mm. Anatomical locations included the splenic hilum (36.0%), distal splenic artery (30.3%), mid-splenic artery (23.9%), and proximal splenic artery (9.7%). Radiographically, the majority were saccular aneurysms (72.4%) with calcifications (88.5%). One patient (38-year-old female) was initially diagnosed at the time of rupture of a 25mm aneurysm; this patient underwent immediate endovascular intervention with no complications. The mean clinical follow-up among 812 patients was 4.1 ± 4.0 years and the mean radiological follow-up among 514 patients was 3.8 ± 6.8 years. Of the latter, 122 patients (23.7%) experienced growth. Aneurysm growth rates for initial sizes < 10mm (n=123), 10-19mm (n=353), 20-29mm (n=34), and >30mm (n=4) were 0.166 mm/yr, 0.172 mm/yr, 0.383 mm/yr, and 0.246 mm/yr, respectively. Of the entire cohort, 27 patients (3.2%) eventually underwent intervention (81.5% endovascular), with the most common indications including size/growth criteria (70.4%) and symptom development (18.5%). On multivariate analysis, only prior tobacco use was significantly associated with aneurysm growth (p=.028). CONCLUSIONS:The majority of SAAs in this cohort remained stable in size, with few patients requiring intervention over mean follow-up of 4 years. Current guidelines recommending treatment of asymptomatic aneurysms >30mm appear appropriate given their slow progression. Despite societal recommendations for intervention for all SAAs among women of childbearing age, only a minority underwent vascular surgical consultation and intervention in this series, indicating that these recommendations are likely not well known in the general medical community.

OBJECTIVE:The necessary training and certification of providers performing venous ablation has become a topic of debate in recent years. As venous interventions have shifted away from the hospital, the diversity of provider backgrounds has increased. We aimed to characterize superficial venous ablation practice patterns associated with different provider types. METHODS:We analyzed Medicare fee-for-service data from 2010 through 2018. Procedures were identified by their Current Procedural Terminology (CPT) code and included radiofrequency ablation, endovenous laser ablation, chemical adhesive ablation (i.e., VenaSeal®), and mechanochemical ablation. These procedures were correlated with the practitioner type to identify provider-specific trends. RESULTS:Between 2010 and 2018, the number of ablation procedures rose by 107% from 114,197 to 236,558 per year (p<0.001). Most procedures were performed by surgeons without vascular board certification (28.7%, 95% CI [28.7, 28.8]), followed by vascular surgeons (27.1%, 95% CI [27.0, 27.2]). Traditionally non-interventional specialties, which exclude surgeons, cardiologists, and interventional radiologists, accounted for 14.1% (95% CI [14.1, 14.2]), and APPs accounted for 3.5% (95% CI [3.4, 3.5]) of all ablation procedures during the time frame. The total number of ablations increased by 9.7% annually (95% CI [9.7, 9.8]), whereas procedures performed by APPs grew by 62.0% annually (95% CI [61.6, 62.4]). There were significant differences between specialties in the use of non-thermal ablation modalities: APPs had the highest affinity for non-thermal ablation (OR 2.60, 95% CI [2.51, 2.69]). Cardiologists were also more likely to use non-thermal ablation (OR 1.62, 95% CI [1.59, 1.66]). Similarly, the uptake of new non-thermal technology (i.e., chemical adhesives) was greatest among APPs (OR 3.57, 95% CI [3.43, 3.70]) and cardiologists (OR 1.86, 95%,CI [1.81, 1.91]). Vascular surgeons were less likely to use non-thermal modalities (OR 0.95, 95% CI [0.92, 0.97]), including new non-thermal technology in the first year of availability (OR 0.93, 95% CI [0.90, 0.95]). CONCLUSIONS:Venous procedures have grown rapidly over the past decade, particularly as endovenous ablations have been performed by a wider practitioner base including APPs and non-interventionalists. Practice patterns differ by provider type, with APPs and cardiologists skewing more toward non-thermal modalities, including more rapid uptake of new non-thermal technology. Provider-specific biases for specific ablation modalities may reflect differences in training, skill set, the need for capital equipment, clinical privileges, or reimbursement. These data may help to inform training paradigms, allocation of resources, and evaluation of appropriateness in a real-world setting.