Duplex Ultrasound Surveillance Research Articles

Duplex Ultrasound–Only Surveillance after Endovascular Abdominal Aortic Aneurysm Repair is Associated with Favorable Long-Term Outcomes

ObjectiveLong-term data surrounding the impact of different endovascular abdominal aortic aneurysm repair (EVAR) surveillance strategies is limited. Therefore, the purpose of this study was to characterize postoperative imaging patterns, as well as to evaluate the association of duplex ultrasound surveillance after the first postoperative year with 5-year EVAR outcomes. MethodsEVAR patients (2003-2016), who survived at least 1-year without aneurysm rupture, conversion to open repair, and reintervention in the Vascular Implant Surveillance and Interventional Outcomes Network (VISION) were examined to provide all subjects ≥3-years of follow-up time. Patients were categorized into 6 cohorts after the first postoperative year: No imaging (N=953); CT/MRI-only (N=2,976); Duplex ultrasound-only (DUS; N=1,808); Combined CT/MRI+DUS with >50% being CT/MRI (N=1,937); Combined CT/MRI+DUS with >50% being DUS (N=2,253); and Mixed (CT+DUS+MRI-N=1,272). Abdominal aortic aneurysm (AAA) related re-intervention, rupture, conversion to open repair, and all-cause mortality were estimated using Kaplan-Meier analysis. Multivariable logistic regression models identified variables associated with using DUS-only imaging (vs. CT/MRI only). Cox regression models compared 5-year outcomes between patients receiving DUS-only vs. CT/MRI-only imaging. ResultsA total of 11,199 EVAR patients were examined (mean age-76±7 years; female-20%; non-elective-10%). DUS-only imaging surveillance after the first postoperative year was more likely to occur after elective repairs, as well as among older, male patients. Smaller (<6cm) preoperative AAA diameter and absence of documented concurrent iliac aneurysm was also associated with DUS-only follow-up. Additionally, no endoleak detection on index EVAR completion imaging, as well as a documented >5mm decrease in AAA sac diameter at 1-year follow-up was more common with DUS-only surveillance protocols. Post-EVAR DUS-only imaging after the first postoperative year had the lowest incidence of re-intervention, conversion to open repair, and rupture (as well as the composite reintervention/open conversion/rupture; log-rank P<.001 for all). Further, patients receiving exclusively DUS after their first postoperative year had better overall survival (log-rank P<.001). These outcome advantages that were associated with DUS-only surveillance compared with CT/MRI-only surveillance after EVAR persisted when controlling for baseline co-variates, preoperative AAA diameter, prior aortic surgery history, sac growth, and presence of endoleak (all P<.01). ConclusionsEVAR patients selected for DUS-only surveillance after the first postoperative year have excellent freedom from AAA-related reintervention, conversion to open repair, rupture and all-cause mortality. These findings remained on multivariable analysis after adjusting for baseline characteristics, endoleak status and sac diameter changes within the first year. This is the first registry-based investigation to document long-term EVAR outcomes for patients entered into a DUS-only monitoring protocol which serves to corroborate the growing evidence base that DUS may be able to supplant CT surveillance in certain subgroups. A prospective randomized multi-center trial comparing DUS versus CT-based imaging after EVAR is needed to validate these findings which may serve to change current practice guidelines, as well as industry and regulatory stakeholder requirements.

Defining an Algorithm for Long-Term Duplex Ultrasound Surveillance after Carotid Intervention

Defining an Algorithm for Long-Term Duplex Ultrasound Surveillance after Carotid Intervention

O104: The “At-Risk” Infrainguinal Bypass Graft: benefit of Duplex Ultrasound Surveillance and Institutional costs of failure

Abstract Introduction The “Achilles heel” of infrainguinal surgical revascularisation (IISR) is that of restenosis. Duplex Ultrasound Surveillance (DUS) is undertaken to identify restenosis to permit intervention to maintain graft patency. We report the impact of DUS on outcomes focusing on patient- and treatment-associated costs. Methods Consecutive patients undergoing IISR at our Institution were assessed (January 2017 - December 2020). Data on DUS (1-, 6- and 12-month scans) were collated. Primary outcomes were mortality and major limb amputations (MLA) at 2-years post IISR. Grafts were defined “at-risk” if radiological evidence of significant graft stenosis or occlusion, with or without symptoms, was identified. Post IISR graft-specific Institutional costs for all patients were quantified. Results 254 patients had IISR in the observed period (196 men, median age 70yrs). Of those, 194 (76%) entered DUS, and 109 (43%) completed it. In patients who completed DUS (vs incomplete vs none), mortality was 6.4%, (vs 26.5% vs 38% respectively; p &amp;lt;0.001) and MLA rates were 6.4% (vs 12% vs 30%, p=0.174 and p&amp;lt;0.001 respectively). Managing at-risk grafts led to additional 384 cross-sectional imaging requests, 284 outpatient reviews, 933 hospital admission days and 233 open and endovascular reinterventions with a total additional NHS cost of £ 1.348.518 in 2 years. Per-patient costs were £216 (per patient, per month) for the complete DUS group vs £348 in no DUS group. Conclusion The ongoing management of IISR is associated with significant costs. Enrolment in and completion of a DUS programme is associated with improved patient outcomes and a reduction in costs.

Surveillance After Surgical and Endovascular Treatment for Peripheral Artery Disease: a Dutch Survey

At present, there is no clear, optimal approach to surveillance after invasive treatment of peripheral artery disease (PAD) in terms of modality, duration, clinical benefit, and cost effectiveness. The ongoing debate on the clinical benefit and cost effectiveness of standard surveillance creates a clear knowledge gap and may result in overtreatment or undertreatment. In this study, a survey was conducted among vascular surgeons in the Netherlands to assess the currently applied surveillance programmes. All vascular surgeons from the Dutch Society for Vascular Surgery received an online survey on follow up after open and endovascular revascularisation in patients with PAD. Surveillance was defined as at least one follow up visit after intervention with or without additional imaging or ankle brachial index (ABI) measurement. Ten types of PAD interventions were surveyed. Surveys were returned by 97 (46.2%) of 210 vascular surgeons, and 76% reported using a routine follow up protocol after an invasive intervention. Clinical follow up only is most commonly performed after femoral endarterectomy (53%). After peripheral bypass surgery, clinical follow up only is applied rarely (4 - 8%). In 6 of the 10 interventions surveyed, duplex ultrasound (DUS) is the most used imaging modality for follow up. After bypass surgery, 76 - 86% of vascular surgeons perform DUS with or without ABI measurement. After endovascular interventions, 21 - 60% perform DUS surveillance. Lifelong surveillance is most applied after aortobifemoral bypass (57%). Surveillance frequency and duration vary greatly within the same intervention. Frequencies range from every 3 months or 6 months to annually. Duration ranges from one time surveillance to lifelong follow up. There is significant practice variation in surveillance after surgical and endovascular treatment of patients with PAD in the Netherlands. We recommend the initiation of prospective studies to evaluate treatment outcomes and to define the clinical need and cost effectiveness of standardised surveillance programmes for patients with PAD.

Surveillance duplex ultrasound prompted interventions after carotid endarterectomy

ObjectiveCurrent societal guidelines recommend duplex ultrasound (DUS) surveillance beyond 30 days after carotid endarterectomy (CEA) for patients with risk factors for restenosis or who underwent primary closure. However, the appropriate duration of this surveillance has not yet been identified, and the rate at which DUS surveillance prompts intervention is unknown. Multiple calls for decreasing health care spending that does not provide value, including unnecessary testing, have been made. The purpose of this study was to examine the rate of intervention prompted by surveillance DUS on the ipsilateral or contralateral carotid artery after CEA and determine the value of continued surveillance by determining the rate of DUS-prompted intervention. MethodsA single-center, retrospective chart review of all patients older than 18 years who had undergone CEA from August 2009 to July 2022 was performed. Patients with at least one postoperative duplex in our Intersocietal Accreditation Council-accredited ultrasound lab were included. Exclusion criteria were patients with incomplete medical charts or patients who underwent a concomitant procedure. The primary end point was return to the operating room for subsequent intervention based on abnormal surveillance DUS findings. Secondary end points were the number of postoperative surveillance duplexes, duration of surveillance, and incidence of perioperative stroke. The study participant data were queried for patients who had a diagnosis of stroke that occurred following their procedure. ResultsA total 767 patients, accounting for 771 procedures, were included in this study, which resulted in 2145 ultrasound scans. A total of 40 (5.2%) patients required 44 subsequent interventions that were prompted by DUS surveillance scans. The average number of ultrasound scans per patient was 2.8 (range: 0-14), and the average duration of surveillance was 26.4 months (range: 0-155 months). Of the 767 patients, 669 (87.2%) had a unilateral CEA. A total of 62 of 767 (8.1%) patients had planned endarterectomies on the contralateral side based on initial imaging, not prompted by interval DUS surveillance scans. Of 767 patients, 28 (3.7%) patients who underwent CEA had a subsequent procedure for progression of contralateral disease, which was prompted by duplex surveillance scans. The average duration between index CEA and intervention on contralateral carotid was 29.57 months (range: 3-81 months). A total of 11 patients, accounting for 12 procedures, underwent a subsequent procedure for restenosis of their ipsilateral carotid, prompted by duplex surveillance scans. The average duration between index CEA and reintervention on the ipsilateral carotid was 17.9 months (range: 4-70 months). Three of 767 (0.4%) patients in total were identified as having a perioperative stroke. ConclusionsThe overall rate of ipsilateral reintervention after CEA is low. A small percentage of patients will progress their contralateral disease, ultimately requiring surgical intervention. These data suggest that regular duplex surveillance after CEA is warranted for patients with at least moderate contralateral disease; however, the yield is low for ipsilateral restenosis after 36 months based on this single institution study. Further study is needed to better delineate which patients need follow-up to decrease unnecessary testing while still targeting patients most at risk of restenosis or contralateral progression of disease.

Increased body mass index and vein diameter are associated with incomplete target vein closure following microfoam ablation of incompetent saphenous veins

ObjectivePatient characteristics and risk factors for incomplete or non-closure following thermal saphenous vein ablation have been reported. However, similar findings have not been clearly described following commercially manufactured polidocanol microfoam ablation (MFA). The objective of our study is to identify predictive factors and outcomes associated with non-closure following MFA of symptomatic, refluxing saphenous veins. MethodsA retrospective review of a prospectively maintained patient database was performed from procedures in our Ambulatory Procedure Unit. All consecutive patients who underwent MFA with commercially manufactured 1% polidocanol microfoam for symptomatic superficial vein reflux between June 2018 and September 2022 were identified. Patients treated for tributary veins only, without truncal vein ablation, were excluded. Patients were then stratified into groups: complete closure (Group I) and non-closure (Group II). Preoperative demographics, procedural details, and postoperative outcomes were analyzed. Preoperative variables that were significant on univariate analysis (prior deep venous thrombosis [DVT], body mass index [BMI] ≥30 kg/m2, and vein diameter) were entered into a multivariate logistic regression model with the primary outcome being vein non-closure. ResultsBetween June 2018 and September 2022, a total of 224 limbs underwent MFA in our ambulatory venous center. Of these, 127 limbs in 103 patients met study inclusion criteria. Truncal veins treated included the above-knee great saphenous vein (Group I: n = 89, 77% vs Group II: n = 7, 58%; P = .14), below-knee great saphenous vein (Group I: n = 7, 6% vs Group II: n = 0; P = .38), anterior accessory saphenous vein (Group I: n = 17, 15% vs Group II: n = 4, 33%; P = .12, and small saphenous vein (Group I: n = 4, 4% vs Group II: n = 1, 8%; P = .41). Complete closure (Group I) occurred in 115 limbs, and 12 limbs did not close (Group II) based on postoperative duplex ultrasound screening. The mean BMI in Group II (36.1 ± 6.4 kg/m2) was significantly greater than Group I (28.6 ± 6.1 kg/m2) (P < .001). Vein diameter of ≥10.2 mm was independently associated with truncal vein non-closure with an odds ratio of 4.8. The overall mean foam volume was 6.2 ± 2.7 ml and not different between the two cohorts (Group I: 6.2 ± 2.6 ml vs Group II: 6.3 + 3.5 ml; P = .89). Post MFA improvement in symptoms was higher in Group I (96.9%) compared with Group II (66.7%) (P = .001). The mean postoperative Venous Clinical Severity Score was also lower in Group I (8.0 ± 3.0) compared with Group II (9.9 ± 4.2) (P = .048). The overall incidences of ablation-related thrombus extension and DVT were 4.7% (n = 6) and 1.6% (n = 2), and all occurred in Group I. All were asymptomatic and resolved with anticoagulation. ConclusionsMicrofoam ablation of symptomatic, refluxing truncal veins results in excellent overall closure rates and symptomatic relief. BMI ≥30 kg/m2 and increased vein diameter are associated with an increased risk of saphenous vein non-closure following MFA. Non-closure is associated with less symptomatic improvement and a lower post-procedure reduction in Venous Clinical Severity Score. Despite the incidence of ablation-related thrombus extension and DVT in this study being higher than reported rates following thermal ablation, MFA is safe for patients with early postoperative duplex ultrasound surveillance and selective short-term anticoagulation.

Duplex ultrasound for surveillance of lower limb revascularisation.

Duplex ultrasound for surveillance of lower limb revascularisation.

Society for Vascular Surgery duplex ultrasound surveillance guidelines are safe and cost effective for transcarotid artery revascularization

BackgroundCarotid duplex ultrasound (CDUS) examination is used in the long-term surveillance after transcarotid artery revascularization (TCAR). The objective of this study was to evaluate the usefulness and cost effectiveness of post-TCAR CDUS surveillance regimens in monitoring for in-stent restenosis (ISR) and associated stroke risk at a single-center community institution. MethodsCDUS data were collected retrospectively from patients who had undergone TCAR between January 2017 and January 2023. ISR >50% was defined as a peak systolic velocity (PSV) of >220 cm/s and an internal carotid artery (ICA) to common carotid velocity ratio of >2.7. ISR >80% was defined as a PSV of >340 cm/s and an ICA/common carotid artery ratio of >4.15. Study outcomes included incidences of ISR, reintervention, transient ischemic attacks (TIAs), strokes, and mortality. A Kaplan-Meier survival analysis was done to calculate the rates of freedom from ISR. ResultsDuring the study period, 108 TCAR stents were deployed in 104 patients. Eight patients were excluded in analysis or lost to follow-up. Preoperatively, 62% of patients had >80% stenosis, and 39% were symptomatic. No intraprocedural complications were noted. One patient suffered an immediate postoperative dissection. Eight stents (8%) experienced ISR progression from <50% to >50%. Three of the eight had further ISR progression to >80%. One patient had high-grade ISR and a contralateral ICA occlusion that warranted reintervention. There were no occurrences of postoperative TIAs, strokes, or TCAR-related deaths. Rates of freedom from ISR progression from <50% to >50% were 97.4%, 95.9%, 90.9%, 88.2%, and 88.2% at 6, 12, 24, 36, and 42 months, respectively. Rates of freedom from ISR >80% were 100%, 100%, 98.5%, 95.5%, and 95.5% at the same time points. Patients with >50% ISR tended to be females with hyperlipidemia. In addition, they had higher average lesion lengths and lower rates of postdilation balloon angioplasty. The 5-year estimated surveillance cost in this cohort using the Society for Vascular Surgery 2022, and 2018 guidelines, as well as our current protocol would be $113,853, $221,382, and $193,207, respectively. ConclusionsThis study revealed a low incidence of ISR progression, as well as no TIA, stroke, or TCAR-related deaths, highlighting the safety and efficacy of TCAR. Post-TCAR CDUS examination using the updated Society for Vascular Surgery guidelines are safe and cost effective. Patients with contralateral occlusion or stenosis, or who have significant risk factors, should have more frequent surveillance regimens.

Abbreviated Duplex Ultrasound Surveillance in TCAR May Be Safe and Cost-Effective

Abbreviated Duplex Ultrasound Surveillance in TCAR May Be Safe and Cost-Effective

Surveillance Duplex Ultrasound Prompted Interventions After Carotid Endarterectomy

Current societal guidelines recommend duplex ultrasound surveillance beyond 30 days after carotid endarterectomy for patients with risk factors for restenosis or who underwent primary closure. However, the appropriate length for this surveillance has not yet been identified, and the rate at which surveillance prompts intervention is unknown. Multiple calls for decreasing health care spending that does not provide value, including unnecessary testing, have been made. The purpose of this study was to examine the rate of intervention prompted by surveillance duplex ultrasound on the ipsilateral or contralateral carotid artery after carotid endarterectomy.

The Natural History of Carotid Artery Occlusions Diagnosed on Duplex Ultrasound

There is a paucity of literature on the natural history of extracranial carotid artery occlusion (CAO). This study reviews the natural history of this patient cohort. This single-institution retrospective analysis studied patients with CAO diagnosed by duplex ultrasound between 2010 and 2021. Patients were identified by searching our office-based IAC accredited vascular laboratory database. Imaging and clinical data were obtained via our institutional Electronic Medical Record. Outcomes of interest included ipsilateral stroke, attributable neurologic symptoms, and ipsilateral intervention after diagnosis. The full duplex database consisted of 5523 patients who underwent carotid artery duplex exam during the study period. The CAO cohort consisted of 139 patients; incidence of CAO was 2.5%. Mean age at diagnosis was 69.7 years; 31.4% were female. Hypertension (72.7%), hyperlipidemia (64.7%), and prior smoking (43.9%) were the most common comorbid conditions. Of the CAO cohort, 61.3% (n=85) of patients were asymptomatic at diagnosis; 38.8% (n=54) were diagnosed after a stroke or transient ischemic attack (TIA) occurring within six months prior to diagnosis, with 21.6% occurring ipsilateral to the CAO and 10.1% occurring contralateral to the CAO. 7.2% (n=10) had unclear symptoms or laterality at presentation. Of the CAO cohort, ninety-five patients (68.3%) had duplex imaging follow-up (mean 42.7±31.3 months). Of those with follow up studies, seven patients (5.0%) developed subsequent stroke ipsilateral to the CAO with mean occurrence 27.8 ±39.0 months post-diagnosis. In addition, five patients (3.6%) developed other related symptoms, including global hypoperfusion, (2.4%) and TIA (1.2%). Of those 95 patients with follow up duplex ultrasound imaging, six (4.3%) underwent eventual ipsilateral intervention, including CEA (n=4), TF-CAS (n=1), and carotid bypass (n=1), with mean occurrence 17.7±23.7 months post-diagnosis. The aggregate rate of ipsilateral CVA, attributable neurologic symptoms, or ipsilateral intervention was 11.5%. Of 95 patients with follow up duplex ultrasound imaging, 5 underwent subsequent duplex studies demonstrating ipsilateral patency, resulting in a 5.3% discrepancy rate between sequential duplex studies. All 6 patients undergoing intervention received periprocedural cross-sectional imaging (MRA or CTA). In 5 of these 6 patients, cross-sectional demonstrated severe stenosis rather than CAO, disputing prior duplex ultrasound findings. In this large, institutional cohort of patients with a CAO diagnosis on duplex ultrasound, a clinically meaningful subset of patients experienced CVA, related symptoms, or intervention. We also found a notable rate of temporal duplex discrepancies among patients with CAO diagnoses, and discrepancies between CAO diagnosis per duplex ultrasound and findings on cross-sectional imaging for those patients who underwent intervention. These results suggest that use of a single duplex ultrasound as a sole diagnostic tool in CAO may not be sufficient, and that physicians should consider close duplex ultrasound surveillance of these patients, potentially in conjunction with additional confirmatory imaging modalities. Further investigation into optimal workup and surveillance protocols for CAO is needed.

Rates of progression of carotid in-stent stenosis and clinical outcomes.

We previously reported the incidence of ≥50% and ≥80% carotid in-stent stenosis. In the present study, we analyzed the rate of progression of in-stent stenosis and clinical outcomes with longer follow-up. We performed a retrospective analysis of prospectively collected data for 450 patients who had undergone transfemoral carotid artery stenting with longer follow-up (mean, 70months). The progression of in-stent stenosis was defined as stenosis advancing to a higher severity of disease (ie, from<50% to ≥50% and from ≥50% to ≥80%). Kaplan-Meier analysis was used to estimate the rate of progression from<50% to ≥50% and ≥50% to ≥80%, the overall rates of ≥50% and ≥80% in-stent stenosis, and survival at 1, 3, 5, and 10years. At a mean follow-up of 70.3months (range, 1-222months), 121 of 446 patients (27%) had had progression to ≥50% and 39 (8.7%) to ≥80% in-stent stenosis. Of the 406 patients whose first duplex ultrasound findings were normal or showed in-stent stenosis of<50%, 82 had had progression from normal or<50% to ≥50% in-stent stenosis at a mean of 51.7months (range, 1-213months). Of the 121 patients with ≥50% stenosis, 14 (11.6%) had experienced progression to ≥80% at a mean of 33.6months (range, 6-89months). Of the 82 patients with progression from<50 to ≥50%, 10 (12%) had experienced a neurologic event (eight transient ischemic attacks [TIAs] and two strokes). Of the 14 with progression from ≥50% to ≥80%, 2 (14.3%) had experienced a TIA, and the remaining patients were asymptomatic. Of the 39 patients with ≥80% in-stent stenosis, 9 (23%) had experienced a neurologic event (eight TIAs and one contralateral stroke). Overall, 13 of the 121 patients with late ≥50% restenosis (10.7%) had experienced a neurologic event (10 ipsilateral TIA, 2 ipsilateral stroke, and 1 contralateral stroke. Thus, 12 of 446 patients (2.7%) had experienced an ipsilateral TIA or stroke at a mean follow-up of 70months. The rates of freedom from<50% to ≥50% in-stent stenosis progression were 93%, 85%, 78%, and 66% at 1, 3, 5, and 10years. The rates of freedom from progression from ≥50% to ≥80% in-stent stenosis were 89%, 81%, and 77% at 1, 3, and 5years, respectively. The overall rates of freedom from ≥50% in-stent stenosis and ≥80% in-stent stenosis were 86%, 77%, 71%, and 59% and 96%, 93%, 91%, and 84% at 1, 3, 5, and 10years, respectively. Finally, the stroke survival rates were 95%, 80%, 63%, and 31% at 1, 3, 5, and 10years, respectively. The rate of progression of carotid in-stent stenosis was modest, with a low incidence of stroke events. Therefore, the use of duplex ultrasound surveillance after carotid artery stenting should be selective and its benefits and utility perhaps reevaluated.

The Risk Assessment Profile is suboptimal for guiding duplex ultrasound surveillance in trauma patients

The utility of the Risk Assessment Profile (RAP) score in predicting VTE was assessed, and VTE risk factors identified to guide a duplex ultrasound (DUS) protocol in injured patients. Secondary analysis of prospective data on trauma inpatients (March 2017 - September 2019), with admission RAP ≥5. Inhospital VTE patients compared to those without. Regression analyses in DVT, PE and proximal DVT, and ROC analysis evaluating RAP's VTE predictability were performed. 1,989 patients were analyzed. VTE was identified in 163(8.2%), DVT 159(8.0%), and PE 10(0.5%) patients. Strongest VTE predictors were massive transfusion (OR 5.97, p=0.005) and spinal cord injury (OR 2.43, p=0.03). AUC 0.61 (p<0.001) on ROC analysis evaluating RAP on VTE. Abdominal injury and major surgery were unique risk factors to non-screened patients. Performance of RAP to predict VTE was moderate. VTE predictor variables could serve as the foundation for a novel approach guiding DUS surveillance. Derivation and validation are warranted.

577 Infra-Inguinal Bypass Graft Surveillance Is an Opportunity to Optimise Statin and Antiplatelet Therapy to Reduce 12-Month Major Amputation and Mortality Rates

Abstract Aim Infra-inguinal bypass graft failure within the first two postoperative years can result from stenotic lesions within the conduit and near anastomosis. This study assesses graft surveillance uptake, patency, amputation, and death rates among infra-inguinal bypass surgery patients at 1, 6 and 12-months postoperatively. Method Patients undergoing infra-inguinal bypass at a single vascular centre between 1st January 2018 and 31st December 2019 were identified from the prospectively collected database. Primary outcomes at 1, 6 and 12-months postoperatively included: duplex-ultrasound (DUS) surveillance uptake, patency, major amputations, and death rates. Statistical analysis with SPSS® was performed using chi-squared tests and paired sample t-tests. Results Of the 91 patients included, 79.1% were men and median(IQR) age was 71(62–76). At 1, 6 and 12 months, DUS uptake was 74.2%, 77.5% and 73.3% respectively, primary-assisted patency rates were 88.2%, 78.8% and 65.3% respectively and secondary patency rates were 97.6%, 96.3% and 96.3% respectively. Major amputation rates at 1, 6 and 12 months were 5.4%, 8.6%, 8.6% respectively. Death rates at 1, 6 and 12 months were 3.2%, 5.4% and 10.8% respectively. Patients on statin therapy post-operatively had lower 12-month mortality than those not on statin therapy (7.7% vs 30.0%, p=.028). Major amputation rate at 12 months was lower among patients prescribed antiplatelet therapy (6.3% vs 40%, p=.008). Conclusions DUS graft surveillance is a vital opportunity to adequately optimise statin and antiplatelet therapy post-revascularisation to reduce 12-month major amputation and mortality rates.

Comparing the Benefit of Duplex Ultrasound Surveillance Following Both Infrainguinal Bypass Surgery and Stenting for Femoro-Popliteal Disease

Duplex ultrasound surveillance (DUS) is commonly used following infrainguinal vein bypass. The role of DUS following endovascular revascularisation is as yet unclear. This study focuses on the role of DUS in a contemporary group of patients undergoing infrainguinal bypass or stent insertion. All patients undergoing either an infrainguinal vein graft bypass or stent insertion into the femoro-popliteal segment (November 2014 - January 2017) were identified. Patients were followed up for 2years. Data on entry into DUS, pre-operative characteristics, adjunctive pharmacotherapy and reintervention were collated. The primary outcomes were major lower limb amputation and mortality at 2years post revascularisation. One hundred and thirty-five patients underwent infrainguinal vein bypass and 100 patients underwent stent insertion. 107 patients in the bypass cohort and 58 patients in the stent cohort entered DUS. For the bypass cohort, entering DUS was associated with a lower mortality rate (P = .003) but was not associated with an improvement in amputation rates. The odds ratio of major amputation or mortality was greater in the no surveillance group (4.58, 95% CI: 1.855 - 11.364). In the stent cohort, DUS was not associated with a significant improvement in either major amputation or death (odds ratio 2.13 (95% CI 0.903 - 5.051; P = .081). DUS was associated with improved survival rates in patients undergoing lower limb bypass but had no benefit in those patients undergoing stent insertion. The role of DUS following stent insertion in the femoropopliteal segment needs to be better defined.

O069 Infra-inguinal bypass graft surveillance is an opportunity to optimise statin and antiplatelet therapy to reduce 12-month major amputation and mortality rates

Abstract Introduction Infra-inguinal bypass graft failure within the first two postoperative years can result from stenotic lesions within the conduit and near anastomosis. This study assesses graft surveillance uptake, patency, amputation and death rates among infra-inguinal bypass surgery patients at 1, 6 and 12-months postoperatively. Methods Patients undergoing infra-inguinal bypass at a single vascular centre between 1st January 2018 and 31st December 2019 were identified from the prospectively collected database. Primary outcomes at 1, 6 and 12-months postoperatively included: duplex-ultrasound (DUS) surveillance uptake, patency, major amputations and death rates. Statistical analysis with SPSS® was performed using chi-squared tests and paired sample t-tests. Results Of the 91 patients included, 79.1% were men and median (IQR) age was 71(62–76). At 1, 6 and 12 months, DUS uptake was 74.2%, 77.5% and 73.3% respectively, primary-assisted patency rates were 88.2%, 78.8% and 65.3% respectively and secondary patency rates were 97.6%, 96.3% and 96.3% respectively. Major amputation rates at 1, 6 and 12 months were 5.4%, 8.6%, 8.6% respectively. Death rates at 1, 6 and 12 months were 3.2%, 5.4% and 10.8% respectively. Patients on statin therapy post-operatively had lower 12-month mortality than those not on statin therapy (7.7% vs 30.0%, p=.028). Major amputation rate at 12 months was lower among patients prescribed antiplatelet therapy (6.3% vs 40%, p=.008). Conclusion DUS graft surveillance is a vital opportunity to adequately optimise statin and antiplatelet therapy post-revascularisation to reduce 12-month major amputation and mortality rates. Take-home message Infra-inguinal bypass graft surveillance is an opportunity to optimise statin and antiplatelet therapy to reduce 12-month major amputation and mortality rates.

Trauma patients at risk for venous thromboembolism who undergo routine duplex ultrasound screening experience fewer pulmonary emboli: A prospective randomized trial.

Although guidelines are established for the prevention and management of venous thromboembolism (VTE) in trauma, no consensus exists regarding protocols for the diagnostic approach. We hypothesized that at-risk trauma patients who undergo duplex ultrasound (DUS) surveillance for lower extremity deep venous thrombosis (DVT) will have a lower rate of symptomatic or fatal pulmonary embolism (PE) than those who do not undergo routine surveillance. Prospective, randomized trial between March 2017 and September 2019 of trauma patients admitted to a single, level 1 trauma center, with a risk assessment profile score of ≥5. Patients were randomized to receive either bilateral lower extremity DUS surveillance on days 1, 3, and 7 and weekly during hospitalization ultrasound group (US) or no surveillance no ultrasound group (NoUS). Rates of in-hospital and 90-day DVT and PE were reported as was DVT propagation and all-cause mortality. Standard care for the prevention and management of VTE per established institutional protocols was provided to all patients. A total of 3,236 trauma service admissions were screened, and 1,989 moderate- and high-risk patients were randomized (US, 995; NoUS, 994). The mean ± SD age was 62 ± 20.1 years, Injury Severity Score was 14 ± 9.7, risk assessment profile was 7.1 ± 2.4, and 97% suffered blunt trauma. There was no difference in demographics or VTE risk factors between the groups. There were significantly fewer in-hospital PE in the US group than the NoUS group (1 [0.1%] vs. 9 [0.9%], p = 0.01). The US group experienced more in-hospital below-knee DVTs (124 [12.5%] vs. 8 [0.8%], p < 0.001) and above-knee DVTs (19 [1.9%] vs. 8 [0.8%], p = 0.05). There was no difference in 90-day PE or DVT, or overall mortality. The implementation of a selective routine DUS protocol was associated with significantly fewer in-hospital PE. More DVTs were identified with routine screening; however, surveillance bias appears to exist primarily with distal DVT. Larger trials are needed to further characterize the relationship between routine DUS screening and VTE outcomes in the high-risk trauma population. Therapeutic/care management, level II.

Duplex ultrasound findings and clinical outcomes of carotid restenosis after carotid endarterectomy.

This study aimed to describe the duplex ultrasound (DUS) findings associated with carotid restenosis after carotid endarterectomy (CEA) and to determine whether carotid restenosis is associated with the clinical outcomes of CEA. Between January 2007 and December 2016, a total of 660 consecutive patients who underwent 717 CEAs were followed up at our hospital with DUS surveillance for at least 3 years after CEA. These patients were analyzed retrospectively for this study. Following CEA, restenosis was defined as the development of ≥50% stenosis, diagnosed on the basis of DUS findings of the luminal narrowing and velocity criteria. The study outcomes were defined as restenosis of the ipsilateral carotid artery after CEA and late (>30days) fatal or nonfatal stroke ipsilateral to the carotid restenosis. During the median follow-up period of 74 months, the restenosis incidence was 2.8% (20/717), and there were 2 strokes (2/20, 10%) ipsilateral to the restenosis after CEA; reintervention was performed for 11 patients with carotid restenosis (55%). Within 2 years after CEA, restenosis was identified in 9 cases (45%, 9/20), and 8 reinterventions (72.7%, 8/11) were performed. According to DUS findings, the morphologic characteristics of carotid restenosis were different from the preoperative plaque morphology. Among the 20 carotid restenosis cases, we observed the following DUS patterns: homogenous isoechoic restenosis (n = 14, 70%), homogenous hypoechoic (n = 2, 10%), isoechoic with hypoechoic surface (n = 3, 15%), and hypoechoic with isoechoic surface (n = 1, 5%). Although 9 carotid restenosis patients received prophylactic reintervention to mitigate the progression of restenosis, the 2 symptomatic restenosis patients had isoechoic lesions with hypoechoic surfaces on DUS. On Kaplan-Meier survival analyses, in terms of stroke-free survival rates, there was a higher risk of stroke among patients with carotid restenosis compared with patients without restenosis, with a non-significant trend (P = 0.051). In conclusion, most carotid restenoses were identified within 2 years after CEA, and there was a non-significant trend toward a higher risk of stroke among patients with carotid restenosis.

Duplex Ultrasound Can Successfully Identify Endoleaks and Renovisceral Stent Patency in Patients Undergoing Complex Endovascular Aneurysm Repair.

Efficacy of duplex ultrasound (DU) surveillance of complex EVAR such as FEVAR and ChEVAR has not been studied. All patients undergoing FEVAR or ChEVAR at a single multihospital institution were retrospectively reviewed. Postoperative surveillance included DU at 1 month and CTA at 3 months. 82 patients met inclusion criteria including 39 (47.6%) ChEVAR and 43 (52.4%) FEVAR cases. DU identified endoleak with aneurysm sac enlargement in 3 cases requiring reintervention. CTA at 3 months detected 2 new endoleaks without growth and 1 renal artery stent occlusion. Replacement of initial postoperative imaging with DU did not result in any missed endoleaks, deaths, ruptures, or branch occlusions.

Duplex Ultrasound Surveillance after Transcarotid Artery Revascularization (TCAR) in Clinical Practice

To propose a protocol for the routine clinical use of duplex ultrasound (DUS) assessment after transcarotid artery revascularization (TCAR) procedures, with its specific point of vascular access, based on DUS data from routine clinical practice. DUS data were retrospectively collected at 2 centers from a total of 97 patients who underwent a TCAR procedure with at least 30-day and up to 12-month follow-up. Peak systolic velocity (PSV), end diastolic velocity (EDV), and the internal carotid artery (ICA)/common carotid artery (CCA) PSV ratio were collected at baseline (≤30days after the procedure) and compared with subsequent measurements. Baseline data were established within 30days after the procedure. There were no access site stenoses, pseudoaneurysms, or dissections detected in follow-up. Average hemodynamics measurements at 12months after the procedure (36% of patients reached this time point to date) were PSV 167±153cm/sec, EDV 51±55cm/sec, and ICA/CCA PSV 2.3±1.9. Five patients (5.2%) exhibited velocities indicative of ≥80% in-stent restenosis (ISR) at 12months after the procedure. Two patients (2.1%) underwent repeat intervention for ISR based on high velocities and before significant clinical consequence. The other 3 patients (3.1%) were asymptomatic and are being managed medically and monitored for neurological symptoms. One intraprocedural stroke (1.0% of total treated) was observed. This protocol not only illustrates the utility of using the CCA for the arterial access sheath for carotid stenting, but also successfully identifies patients with clinically significant restenosis >80%-99%. A surveillance regimen of baseline at ≤30days after the procedure, followed by assessment at 6 and 12months, and yearly thereafter appears to be a safe and effective protocol, based on the data available to date. A PSV >340cm/sec and ICA/CCA ratio >4.15 is consistent with an 80-99% restenosis after TCAR. Although a small number, this study serves as a starting point for those who perform TCAR to specifically look at the CCA access site to rule out these potential pitfalls which did occur in the early trials.