Activated clotting time-guided heparinization during open AAA surgery: a pilot study

BACKGROUND

Arterial thrombo-embolic complications (TEC) are still common during and after non-cardiac arterial procedures (NCAP). While unfractionated heparin has been used during NCAP for more than 70 years to prevent TEC, there is no consensus regarding the optimal dosing strategy. The aim of this pilot study was to test the effectiveness and feasibility of an activated clotting time (ACT)-guided heparinization protocol during open abdominal aortic aneurysm (AAA) surgery, in anticipation of a randomized controlled trial (RCT) investigating if ACT-guided heparinization leads to better clinical outcomes compared to a single bolus of 5000 IU of heparin.

METHODS

A prospective multicentre pilot study was performed. All patients undergoing elective open repair for an AAA (distal of the superior mesenteric artery) between March 2017 and January 2020 were included. Two heparin dosage protocols were compared: ACT-guided heparinization with an initial dose of 100 IU/kg versus a bolus of 5000 IU. The primary outcome was the effectiveness and feasibility of an ACT-guided heparinization protocol with an initial heparin dose of 100 IU/kg during open AAA surgery. Bleeding complications, TEC, and mortality were investigated for safety purposes.

RESULTS

A total of 50 patients were included in the current study. Eighteen patients received a single dose of 5000 IU of heparin and 32 patients received 100 IU/kg of heparin with additional doses based on the ACT. All patients who received the 100 IU/kg dosing protocol reached the target ACT of > 200 s. In the 5000 IU group, TEC occurred in three patients (17%), versus three patients (9.4%) in the 100 IU/kg group. Bleeding complications were found in six patients (33%) in the 5000 IU group and in 9 patients (28%) in the 100 IU/kg group. No mortality occurred in either group.

CONCLUSIONS

This pilot study demonstrated that ACT-guided heparinization with an initial dose of 100 IU/kg appears to be feasible and leads to adequate anticoagulation levels. Further randomized studies seem feasible and warranted to determine whether ACT-guided heparinization results in better outcomes after open AAA repair.

Long-Term Outcomes of Nonoperative and Surgical Management of Paget-Schroetter Syndrome

PURPOSE

In Paget-Schroetter Syndrome (PSS), subclavian vein thrombosis is caused by external compression of the subclavian vein at the costoclavicular junction. Paget-Schroetter Syndrome can be treated nonoperatively, surgically, or with a combination of treatments. Nonoperative management consists, in most cases, of anticoagulation (AC) or catheter-directed thrombolysis (CDT). With surgical management, decompression of the subclavian vein is performed by resection of the first rib. No prospective randomized trials are available to determine whether nonoperative or surgical management is superior. We report our long-term outcomes of both nonoperative and surgically treated patients.

MATERIALS AND METHODS

We retrospectively analyzed all patients with PSS who were treated between January 1990 and December 2015. Patients were divided based on primary nonoperative or primary surgical therapy. Long-term outcomes regarding functional outcomes were assessed by questionnaires using the "Disability of the Arm, Shoulder, and Hand" (DASH) questionnaire, a modified Villalta score, and a disease-specific question regarding lifestyle changes.

RESULTS

In total, 91 patients (95 limbs) were included. Seventy patients (73 limbs) were treated nonoperatively and 21 patients (22 limbs) surgically. Questionnaires were returned by 67 patients (70 limbs). The mean follow-up was 184 months (range, 43-459 months). All functional outcomes were better in the surgical group compared with the nonoperatively treated group (DASH general 3.11 vs 9.86; DASH work 0.35 vs 11.47; DASH sport 5.85 vs 17.98, and modified Villalta score 1.11 vs 3.20 points). Surgically treated patients were more likely to be able to continue their original lifestyle and sports activities (84% vs 40%, p=0.005). Patients with recurrence of thrombosis or the need for surgical intervention after primary nonoperative management reported worse functional outcomes.

CONCLUSION

Surgical management of PSS with immediate CDT followed by first rib resection leads to excellent functional outcomes with low risk of complications. The results of nonoperative management in our non-matched retrospective comparative series were satisfactory, but resulted in worse functional outcomes and more patients needing to adjust their lifestyle compared with surgically treated patients.

CLINICAL IMPACT

Patients with Paget-Schroetter Syndrome and their attending physicians are burdened by the lack of evidence concerning the optimal treatment of this entity. Case series comparing the outcomes of non-operative treatment with surgical treatment are scarce and often not focussed on functional outcomes. Data from this series can aid in the shared decision making after diagnosis of Paget-Schroetter Syndrome. Functional outcomes of non-operative management can be satisfying although high demand patient who are not willing to alter their daily activities are probably better off with surgical management.

International Perspective on Extremity Vascular Trauma in Children: A Scoping Review

OBJECTIVE

Extremity vascular trauma in children can result in significant morbidity and mortality. Most published studies have focused on supracondylar humeral fracture related injuries, with little focus on other injuries. This scoping review describes the current state of knowledge on paediatric vascular injuries in the upper and lower limbs, excluding injuries related to supracondylar humeral fractures.

METHODS

MEDLINE, PubMed, Web of Science, and Cochrane databases were searched for relevant studies evaluating the epidemiology, diagnosis, management, and outcomes of upper and lower limb vascular trauma in those aged under 18 years. Studies related to supracondylar humeral fractures were excluded. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for Scoping Reviews was used.

RESULTS

A total of 39 studies was included, all of which were retrospective, and 74% of which were based in North America or Europe. Extremity vascular trauma was reported to cause 0.6 - 4.4% of all paediatric trauma admissions, with penetrating mechanisms and upper limb injuries being the most common. Operative intervention was reported in 80 - 100% of children in the included studies. Primary repair was the most commonly reported operative intervention, followed by interposition graft and bypass graft. Synthetic graft use was less commonly reported (incidence range 0.5 - 33%). Lower limb fasciotomies and amputations were not commonly reported (incidence range 0 - 23% and 0 - 13%, respectively). The mortality rate appeared low, with 23 studies reporting no deaths (incidence range 0 - 4%). Complications were reported inconsistently, with no uniform outcome or follow up measures used.

CONCLUSION

The incidence of extremity vascular trauma appears low in children, with penetrating mechanisms and upper extremity injuries appearing to dominate. Most studies are from high income countries, with probable selection bias towards those treated by operative intervention. Prospective studies are required focusing on patterns of injury, rates of operative and endovascular intervention, and long term outcomes.

Acute kidney injury in patients undergoing endovascular or open repair of juxtarenal or pararenal aortic aneurysms

BACKGROUND

The aim of this cohort study was to report the proportion of patients who develop periprocedural acute kidney injury (AKI) after endovascular repair (ER) and open surgery (OS) in patients with juxta/pararenal abdominal aortic aneurysm and to assess potential risk factors for AKI. The study also aimed to report the short- and long-term outcomes of patients with and without AKI.

METHODS

This was a multicenter cohort study of five European academic high-volume centers (>50 OS or 50 ER infrarenal AAA repairs, plus >15 complex AAA repairs per year). All consecutively treated patients were extracted from a prospective vascular surgical registry and the data were scrutinized retrospectively. The primary end point for this study was the development of AKI. AKI was diagnosed when there is a two-fold increase of serum creatinine or decrease of glomerular filtration rate of >50% within 1 week of AAA repair. Secondary end points included long-term mortality and end-stage renal disease (ESRD).

RESULTS

AKI occurred in 16.6% of patients in the ER group vs 30.3% in the OS group (P < .001). The 30-day mortality rate was higher among patients with AKI in both ER (15.4% vs 3.1%; P = .006) and OS (13.2% vs 5.3%; P = .001) groups. Age, chronic kidney disease, presence of significant thrombus burden in the pararenal region, >1000 mL blood loss in ER group were associated with development of AKI. Age, diabetes mellitus, chronic kidney disease, presence of significant thrombus burden in the pararenal region, and a proximal clamping time of >30 minutes in the OS group were associated with the development of AKI, whereas renal perfusion during clamping was the protective factor against AKI development. After a median follow-up of 91 months, AKI was associated with higher mortality rates in both the ER group (58.9% vs 29.7%; P < .001) and the OS group (61.5% vs 27.3%; P < .001). After the same follow-up period, AKI was associated with a higher incidence of ESRD in both the ER group (12.8% vs 3.6%; P = .009) and the OS group (9.9% vs 2.9%; P < .001).

CONCLUSIONS

The current study identified important pre and postoperative factors associated with AKI after juxta/pararenal abdominal aortic aneurysm repair. Patients with postoperative AKI had significantly higher short- and long term mortality and higher incidence of ESRD than patients without AKI.

Endovascular Repair of Juxtarenal and Pararenal Abdominal Aortic Aneurysms Using a Novel Low-Profile Fenestrated Custom-Made Endograft: Technical Details and Short-Term Outcomes

INTRODUCTION

The aim of this study is to share preliminary experiences and outcomes with a novel custom-made fenestrated TREO® Abdominal Stent-Graft System to treat juxtarenal and pararenal abdominal aortic aneurysms (AAAs).

METHODS

Juxtarenal and pararenal AAA patients treated with the custom-made fenestrated TREO® Abdominal Stent-Graft System were included from 4 high-volume European academic medical centers from June 2021 to September 2023. Technical success and 30-day/in-hospital mortality and complications were analyzed. Technical success was defined as successful endovascular implantation of the stent graft with preservation of antegrade flow to the target vessels, and absence of type 1 or 2 endoleak (EL) at the first postoperative computed tomography angiography (CTA).

RESULTS

Forty-two consecutive patients were included. The majority of the devices were constructed with 2 (N=4; 9.5%), 3 (N=9; 21.4%), or 4 (N=27; 64%) fenestrations. In 1 case, the device was constructed with a single fenestration (2.4%) and 1 device contained 5 fenestrations (2.4%); 17% had previous AAA repair. Target vessel cannulation with placement of a bridging stent was successful in all but 1 vessel (99, 3%). One aneurysm-related death occurred in the direct postoperative period and 2 limb occlusions necessitated reintervention during admission. In the median follow-up period of 101 (2-620) days, 3 more patients died due to non-aneurysm-related causes. Technical success was achieved in 90% of the cases. Nineteen ELs were seen on the first postoperative CT scan: 1 type 1b EL (N=1; 2%), 15 type 2 ELs (N=15; 36%), and 3 type 3 ELs (N=3%). Eleven patients received more than 1 CT scan during a median follow-up of 361 days (82-620): 3 type 2 ELs resolved and 1 type 3 EL was treated in this period. In the follow-up, 1 patient had a coagulation disorder that caused occlusions of the branches.

CONCLUSION

The results of the first experiences using the custom-made fenestrated TREO® Abdominal Stent-Graft System in Europe are promising. There was a low short-term mortality and morbidity rate in these patients of which 17% had previous AAA repair. Mid-term and long-term follow-up data are needed to evaluate endograft durability and performance.

CLINICAL IMPACT

This study shows the first experiences and short-term results of a novel low-profile custom-made device: the custom-made fenestrated TREO® Abdominal Stent-Graft System. Showing these results and experiences can help the physicians in clinical decision-making for their patients.

What we have learned from in-vitro studies of the chimney endovascular technique for treatment of complex abdominal aortic aneurysms: A systematic review

BACKGROUND

A considerable number of patients with abdominal aortic aneurysms (AAA) is not eligible for standard endovascular repair. These complex cases require alternative surgical approaches including the readily available chimney graft endovascular aneurysm repair (Ch-EVAR) or sealing (Ch-EVAS). The optimal configuration for Ch-EVAR or Ch-EVAS is important for success but not yet known.

OBJECTIVE

The aim of the present study was to analyze current data of the outcomes of in-vitro chimney graft treatment in complex AAA.

METHODS

A systematic review following PRISMA guidelines was conducted including studies reporting on gutter size, main graft compression, and chimney graft compression in in-vitro configurations.

RESULTS

The search resulted in 285 articles. 11 studies considering 219 individual tests could be included. Gutter size was comparable between Ch-EVAR and Ch-EVAS configurations. In Ch-EVAR set-ups, the deployed BECG were Advanta V12, VIABAHN®, and BeGraft. One type of SECG was used: VIABAHN®. The four types of main grafts (MG) deployed were: Endurant™ I/II; EXCLUDER Conformable AAA Endoprosthesis and AAA Endoprosthesis, and AFX™ Endovascular AAA Delivery System. In the EVAS-configurations, the Nellix® EVAS system was deployed. In general, SECG presented smaller gutters with higher chimney graft compression. 30% main grafts oversizing seems to give the smallest gutters without high risk of infolding of MG. Oversizing, EndoAnchors, and secondary endobag filling (in Ch-EVAS) reduced gutter sizes. CG ballooning during the entire polymer injection in Ch-EVAS prevented CG compression.

CONCLUSION

In-vitro investigations provide insight in optimal Ch-EVAR and Ch-EVAS configurations for simulated complex AAA repair. The findings above might aid physicians in their planning to potential CG set-ups and can be used in future research to refine the most optimal configuration for chimney graft technique in complex AAA.

Management of Paget-Schroetter Syndrome: a Systematic Review and Meta-Analysis

OBJECTIVE

Currently, there is no consensus on the optimal management of Paget-Schroetter syndrome (PSS). The objective was to summarise the current evidence for management of PSS with explicit attention to the clinical outcomes of different management strategies.

DATA SOURCES

The Cochrane, PubMed, and Embase databases were searched for reports published between January 1990 and December 2021.

REVIEW METHODS

A systematic review and meta-analysis was conducted following PRISMA 2020 guidelines. The primary endpoint was the proportion of symptom free patients at last follow up. Secondary outcomes were success of initial treatment, recurrence of thrombosis or persistent occlusion, and patency at last follow up. Meta-analyses of the primary endpoint were performed for non-comparative and comparative reports. The quality of evidence was assessed using the GRADE approach.

RESULTS

Sixty reports were included (2 653 patients), with overall moderate quality. The proportions of symptom free patients in non-comparative analysis were: anticoagulation (AC), 0.54; catheter directed thrombolysis (CDT) + AC, 0.71; AC + first rib resection (FRR), 0.80; and CDT + FRR, 0.96. Pooled analysis of comparative reports confirmed the superiority of CDT + FRR compared with AC (OR 13.89, 95% CI 1.08 - 179.04; p = .040, I2 87%, very low certainty of evidence), AC + FRR (OR 2.29, 95% CI 1.21 - 4.35; p = .010, I2 0%, very low certainty of evidence), and CDT + AC (OR 8.44, 95% CI 1.12 - 59.53; p = .030, I2 63%, very low certainty of evidence). Secondary endpoints were in favour of CDT + FRR.

CONCLUSION

Non-operative management of PSS with AC alone results in persistent symptoms in 46% of patients, while 96% of patients managed with CDT + FFR were symptom free at end of follow up. Superiority of CDT + FRR compared with AC, CDT + AC, and AC + FRR was confirmed by meta-analysis. The overall quality of included reports was moderate, and the level of certainty was very low.

The Additional Value of Activated Clotting Time-Guided Heparinization During Interventions for Peripheral Arterial Disease

PURPOSE

Unfractionated heparin is widely used to lower the risk of arterial thromboembolic complications (ATECs) during interventions for peripheral arterial disease (PAD), but it is still unknown which heparin dose is the safest in terms of preventing ATECs and bleeding complications. This study aims to evaluate the incidence of complications during interventions for PAD and the relation between this incidence and different heparinization protocols.

MATERIALS AND METHODS

A retrospective analysis of a prospective multicenter cohort study was performed. Between June 2015 and September 2022, 355 patients who underwent peripheral interventions for PAD were included. All patients who were included before July 2018 received 5000 international units (IU) of heparin (group 1). Starting from July 2018, all included patients received an initial dose of 100 IU/kg, with potential additional heparin doses based on activated clotting time (ACT) values (group 2). Data on ACT values and complications within 30 days post-procedurally were collected.

RESULTS

In total, 24 ATECs and 48 bleeding complications occurred. In group 1, 8.7% (n=11) of patients suffered from ATEC, compared with 5.7% (n=13) in group 2. Thirteen percent of patients (n=17) in group 1 had a bleeding complication, compared with 14% (n=31) in group 2. Arterial thromboembolic complications were more often found in patients with peak ACT values of <200 seconds, compared with ACT values between 200 and 250 seconds, 15% (n=6) versus 5.9% (n=9), respectively, p=0.048. Patients with peak ACT values >250 seconds had a higher incidence of bleeding complications compared with an ACT between 200 and 250 seconds, 24% (n=21) versus 9.8% (n=15), respectively, p=0.003. Forty-four percent of patients (n=23) in group 1 reached a peak ACT of >200 seconds, compared with 95% (n=218) of patients in group 2 (p=0.001).

CONCLUSION

ATEC was found in 6.8% (n=24) and bleeding complications in 14% (n=48) of patients who underwent a procedure for PAD. There was a significantly higher incidence of ATECs in patients with a peak ACT value <200 seconds, and a higher incidence of bleeding complications in patients with a peak ACT value >250 seconds. The findings obtained from this study may serve as a basis for conducting future research on heparinization during procedures for PAD, with a larger sample size.

CLINICAL IMPACT

Heparin is administered during arterial interventions for peripheral arterial disease (PAD) to decrease the risk of arterial (thrombo)embolic complications (ATEC) during or shortly following surgery. The effect of heparin is unpredictable in the individual patient, and the optimal dosage of this anticoagulant has not yet been established. Using the activated clotting time (ACT), the anticoagulatory effect of heparin can be monitored periprocedurally. Previous research on the incidence of both ATEC and bleeding complications, or on the optimal dosage of heparin administration, is scarce. This study aims to investigate the incidence of ATEC and bleeding complications between 2 different dosage protocols of heparin-a standard bolus of 5000 IU or ACT-guided heparinization-and thereby provide clarity on the optimal dose of heparin during peripheral arterial interventions for PAD.

The Effect of Smoking on the Activated Clotting Time and the Incidence of Complications in Noncardiac Arterial Procedures

PURPOSE

Smoking is a well-known risk factor for developing arterial diseases and for an increase of complications during and after vascular procedures. Although smoking has a proven effect on hemostasis, no literature is available on the effect of smoking on the activated clotting time (ACT), which is used to monitor the effect of heparin during noncardiac arterial procedures (NCAP). The aim of this study was to examine the effect of smoking on ACT values and the incidence of complications during the same admission or 30 day follow-up of NCAP.

MATERIALS AND METHODS

A post hoc analysis of a prospective multicenter cohort study was performed. Patients older than 18 years, who underwent NCAP between December 2016 and April 2021, were enrolled. Patients were divided into 2 groups based on smoking status: never/former smokers and current smokers. Two heparin dosing protocols were used: an initial bolus of 5000 IU or 100 IU/kg bodyweight.

RESULTS

In total, 773 patients met the inclusion criteria. Five minutes after administration of 5000 IU of heparin, mean ACT values were 190 and 196 seconds for nonsmokers and smokers, respectively (p=0.078). After 100 IU/kg of heparin, mean ACT values were 229 and 226 seconds for nonsmokers and smokers, respectively (p=0.37). Incidence of complications in the whole study cohort was not significantly different for nonsmokers compared with smokers (arterial thrombo-embolic complication [ATEC] 4.7% vs 5.7% p=0.55; hemorrhagic complications 15% vs 18% p=0.29). In subgroup-analysis, a significant difference between smoking groups was found for hemorrhagic complications after open aneurysm repair (p=0.024). However, after adjusting for confounders, the difference between the smoking groups annulled.

CONCLUSION

The results of this study suggest that smoking does not have a significant effect on ACT values or on the incidence of complications in NCAP. Large-scale studies are required to further analyze potential factors having an effect on the ACT and perioperative and postoperative complications, which could help individualize heparinization strategy.

CLINICAL IMPACT

There is high variance between patients in their response on administration of heparin, this is not yet fully understood. This study investigated the effect of smoking in a large prospective multicentre cohort. The results suggests that active smoking does not have an effect on the activated clotting time after administration of heparin. Also no significant effect of smoking could be found on the incidence of all registered complications. Monitoring of the effect of heparin remains important to provide patients with safe anticoagulation during vascular procedures.

Quantitative Magnetic Resonance Imaging to Assess Progression and Rupture Risk of Aortic Aneurysms: A Scoping Review

PURPOSE

In current practice, the diameter of an aortic aneurysm is utilized to estimate the rupture risk and decide upon timing of elective repair, although it is known to be imprecise and not patient-specific. Quantitative magnetic resonance imaging (MRI) enables the visualization of several biomarkers that provide information about processes within the aneurysm and may therefore facilitate patient-specific risk stratification. We performed a scoping review of the literature on quantitative MRI techniques to assess aortic aneurysm progression and rupture risk, summarized these findings, and identified knowledge gaps.

METHODS

Literature concerning primary research was of interest and the medical databases PubMed, Scopus, Embase, and Cochrane were systematically searched. This study used the PRISMA protocol extension for scoping reviews. Articles published between January 2010 and February 2023 involving animals and/or humans were included. Data were extracted by 2 authors using a predefined charting method.

RESULTS

A total of 1641 articles were identified, of which 21 were included in the scoping review. Quantitative MRI-derived biomarkers were categorized into hemodynamic (8 studies), wall (5 studies) and molecular biomarkers (8 studies). Fifteen studies included patients and/or healthy human subjects. Animal models were investigated in the other 6 studies. A cross-sectional study design was the most common, whereas 5 animal studies had a longitudinal component and 2 studies including patients had a prospective design. A promising hemodynamic biomarker is wall shear stress (WSS), which is estimated based on 4D-flow MRI. Molecular biomarkers enable the assessment of inflammatory and wall deterioration processes. The ADAMTS4-specific molecular magnetic resonance (MR) probe showed potential to predict abdominal aortic aneurysm (AAA) formation and rupture in a murine model. Wall biomarkers assessed using dynamic contrast-enhanced (DCE) MRI showed great potential for assessing AAA progression independent of the maximum diameter.

CONCLUSION

This scoping review provides an overview of quantitative MRI techniques studied and the biomarkers derived from them to assess aortic aneurysm progression and rupture risk. Longitudinal studies are needed to validate the causal relationships between the identified biomarkers and aneurysm growth, rupture, or repair. In the future, quantitative MRI could play an important role in the personalized risk assessment of aortic aneurysm rupture.

CLINICAL IMPACT

The currently used maximum aneurysm diameter fails to accurately assess the multifactorial pathology of an aortic aneurysm and precisely predicts rupture in a patient-specific manner. Quantitative magnetic resonance imaging (MRI) enables the detection of various quantitative parameters involved in aneurysm progression and subsequent rupture. This scoping review provides an overview of the studied quantitative MRI techniques, the biomarkers derived from them, and recommendations for future research needed for the implementation of these biomarkers. Ultimately, quantitative MRI could facilitate personalized risk assessment for patients with aortic aneurysms, thereby reducing untimely repairs and improving rupture prevention.

Unfractionated heparin and the activated clotting time in non-cardiac arterial procedures

INTRODUCTION

Unfractionated heparin is administered during non-cardiac arterial procedures (NCAP) to prevent thromboembolic complications. In order to achieve a safe level of anticoagulation, the effect of heparin can be measured. The aim of this review was to provide an overview on what is known about heparin, suggested tests to monitor the effect of heparin, including the activated clotting time (ACT), and the factors that could influence that ACT.

EVIDENCE ACQUISITION

A literature search in PubMed was performed. Articles reporting on heparin, clotting time tests (including thrombin time, activated partial thromboplastin time, anti-activated factor X and ACT), and ACT measurement devices were selected.

EVIDENCE SYNTHESIS

Heparin has a non-predictable effect in the individual patient, which could be measured using the ACT. However, ACT values can be influenced by many factors, such as hemodilution, hypothermia and thrombocytopenia. In addition, a high variation in ACT outcomes is found between measurement devices of different brands. In the sparse literature on the role of ACT during NCAP, no consensus has been reached on optimal target ACT values. An ACT >250 seconds leads to more bleeding complications. Females have a longer ACT after heparin administration, with a higher risk of bleeding complications.

CONCLUSIONS

The effect of heparin is unpredictable. ACT can be used to monitor the effect of heparin and achieve individualized anticoagulation, tailored to the patient and the specifics of the operative procedure. However, the ACT itself can be affected by several factors and caution must be present, as measured ACT values differ between measurement devices.

Early Versus Delayed Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury: A Propensity Score-Matched Analysis

OBJECTIVE

We examined early (≤24 h) versus delayed (>24 h) thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI), taking the aortic injury severity into consideration.

BACKGROUND

Current trauma surgery guidelines recommend delayed TEVAR following BTAI. However, this recommendation was based on small studies, and specifics regarding recommendation strategies based on aortic injury grades are lacking.

METHODS

Patients undergoing TEVAR for BTAI in the American College of Surgeons Trauma Quality Improvement Program between 2016 and 2019 were included and then stratified into 2 groups (early: ≤24 h vs. delayed: >24 h). In-hospital outcomes were compared after creating 1:1 propensity score-matched cohorts, matching for demographics, comorbidities, concomitant injuries, additional procedures, and aortic injury severity based on the acute aortic syndrome (AAS) classification.

RESULTS

Overall, 1339 patients were included, of whom 1054(79%) underwent early TEVAR. Compared with the delayed group, the early group had significantly less severe head injuries (early vs delayed; 25% vs 32%; P =0.014), fewer early interventions for AAS grade 1 occurred, and AAS grade 3 aortic injuries often were intervened upon within 24 hours (grade 1: 28% vs 47%; grade 3: 49% vs 23%; P <0.001). After matching, the final sample included 548 matched patients. Compared with the delayed group, the early group had a significantly higher in-hospital mortality (8.8% vs 4.4%, relative risk: 2.2, 95% CI: 1.1-4.4; P =0.028), alongside a shorter length of hospital stay (5.0 vs 10 days; P =0.028), a shorter intensive care unit length of stay (4.0 vs 11 days; P <0.001) and fewer days on the ventilator (4.0 vs 6.5 days; P =0.036). Furthermore, regardless of the higher risk of acute kidney injury in the delayed group (3.3% vs 7.7%, relative risk: 0.43, 95% CI: 0.20-0.92; P =0.029), no other differences in in-hospital complications were observed between the early and delayed group.

CONCLUSION

In this propensity score-matched analysis, delayed TEVAR was associated with lower mortality risk, even after adjusting for aortic injury grade.

Perprocedural Heparinization in Non-cardiac Arterial Procedures: The Current Practice in the Netherlands

PURPOSE

Heparin is the most widely-used anticoagulant to prevent thrombo-embolic complications during non-cardiac arterial procedures (NCAP). Unfortunately, there is a lack of evidence and consequently non-uniformity in guidelines on perprocedural heparin management. Detailed insight into the current practice of antithrombotic strategies during NCAP in the Netherlands is important, aiming to identify potential optimal protocols and local differences concerning perprocedural heparinization.

MATERIALS AND METHODS

A comprehensive online survey was distributed electronically to vascular surgeons of every hospital in the Netherlands in which NCAP were performed. Data were collected from September 2020 to October 2021.

RESULTS

The response rate was 90% (53/59 hospitals). During NCAP, all surgeons generally administered heparin before arterial clamping. In 74% (39/54) of hospitals, a single heparin dosing protocol was used for all types of patients and vascular procedures. In 40%, there was no uniformity in heparin dosing between vascular surgeons. Depending on the procedure, a fixed bolus heparin, predominantly 5000 IU, was administered in 73% to 93%. In the remaining hospitals (7%-27%), a bodyweight-based heparin protocol was used, with an initial dose of 70 or 100 IU/kg. A minority (28%) monitored the effect of heparin in patients using the activated clotting time add (ACT) after activated clotting time. Target values varied between 180 and 250 seconds or 2 times the baseline ACT.

CONCLUSION

This survey demonstrates considerable variability in perprocedural heparinization during NCAP in the Netherlands. Future research on heparin dosing is needed to harmonize and optimize heparin dosage protocols and contemporary guidelines during NCAP, and thereby improve vascular surgical care and patient safety.

CLINICAL IMPACT

This survey demonstrated persisting intra- and inter-hospital variability in perprocedural heparinization during non-cardiac arterial procedures (NCAP) in the Netherlands. The observed variability in heparinization strategies highlights the need for high quality evidence on perprocedural anticoagulation strategies. This is needed in order to harmonize and optimize heparin dosage protocols and contemporary guidelines and thereby improve vascular surgical patient care. Based on the current results, an international survey will be conducted by the authors to gain additional insight into the antithrombotic strategies used during NCAP, aiming to harmonize anticoagulation protocols worldwide.

Sex Related Outcomes Following Thoracic Endovascular Aortic Repair for Blunt Thoracic Aortic Injury

OBJECTIVE

Current literature suggests that thoracic endovascular aortic repair (TEVAR) in older patients with aortic aneurysms results in higher peri-operative mortality and lower long term survival in females compared with males. However, sex related outcomes in younger patients with blunt thoracic aortic injury (BTAI) undergoing TEVAR remain unknown. This study examined the association between sex and outcomes after TEVAR for BTAI.

METHODS

A retrospective cohort study was performed of all patients who underwent TEVAR for BTAI in the American College of Surgeons Trauma Quality Improvement Program (ACS-TQIP) between 2016 and 2019. The primary outcome was in hospital death. Secondary outcomes were peri-operative complications. Multivariable logistic regression was used to adjust for demographics, comorbidities, injury severity score, and aortic injury grade.

RESULTS

Two thousand and twenty-two patients were included; 26% were female. Compared with males, females were older (46 [IQR 30, 62] vs. 39 [IQR 28, 56] years; p < .001), more often obese (41% vs. 33%; p = .005), had lower rates of alcohol use disorder (4.1% vs. 8.9%; p < .001) and a higher prevalence of hypertension (29% vs. 22%; p = .001). The injury severity was comparable between females and males (Injury Severity Score ≥ 25; 84% vs. 80%; p = .11) and there was no difference in aortic injury grades when comparing females with males (grade 1, 33% vs. 33%; grade 2, 24% vs. 25%; grade 3, 43% vs. 40%; grade 4, 0.8% vs. 1.3%; p = .53). Multivariable logistic regression demonstrated no difference for in hospital mortality between females and males (OR 1.02; 95% CI 0.67 - 1.53, p = .93). Compared with males, females were at lower risk of acute kidney injury (AKI) (OR 0.33; 95% CI 0.17 - 0.64; p = .001) and ventilator associated pneumonia (VAP) (OR 0.50; 95% CI 0.28 - 0.91; p = .023).

CONCLUSION

This study did not demonstrate a sex related in hospital mortality difference following TEVAR for BTAI. However, female sex was associated with a lower risk of AKI and VAP. Future studies should evaluate sex differences and long term outcomes following TEVAR in patients with BTAI.

Short Term and Long Term Clinical Outcomes of Endovascular versus Open Repair for Juxtarenal and Pararenal Abdominal Aortic Aneurysms Using Propensity Score Matching: Results from Juxta- and pararenal aortic Aneurysm Multicentre European Study (JAMES)

OBJECTIVE

The aim of this study was to compare the short and long term clinical outcomes of endovascular (EVAR) vs. open surgical repair (OSR) of juxtarenal (JAAAs) and pararenal abdominal aortic aneurysms (PAAAs) in five high volume European academic centres.

METHODS

This was a retrospective multicentre cohort study of five high volume European academic centres (> 50 open or 50 endovascular abdominal aortic aneurysm repairs annually) including 834 consecutive patients who were operated on and prospectively followed. Using propensity score matching (PSM) each patient who underwent OSR was matched with one patient who underwent EVAR in a 1:1 ratio (145 patients per group). The primary endpoint was long term all cause mortality, while the secondary endpoint was freedom from aortic related re-intervention.

RESULTS

After a follow up of 87 months, no difference in overall survival between the two groups was observed (38.6% for EVAR vs. 42.1% for OSR; p = .88). Patients undergoing EVAR underwent aortic related re-interventions more frequently (24.1% vs. 6.9%; p < .001). Acute kidney injury (AKI) occurred more frequently in patients in the OSR group (40.7% vs. 24.8%; p = .006). However, most patients who suffered from AKI recovered without further progression to renal failure. In hospital (3.4% for EVAR vs. 4.1% for OSR; p = 1.0) and 30 day (4.1% for EVAR vs. 5.5% for OSR; p = .80) mortality rates did not differ between groups.

CONCLUSION

Both open and endovascular treatment can be performed in high volume aortic centres with low short term mortality and morbidity rates, and good long term outcomes. These data provide useful information to help patients choose between the two procedures when both are feasible.

Catheter Directed Thrombolysis for Not Immediately Threatening Acute Limb Ischaemia: Systematic Review and Meta-Analysis

OBJECTIVE

This systematic review and meta-analysis reports the outcomes of catheter directed thrombolysis (CDT) in patients with not immediately threatening (Rutherford I) acute lower limb ischaemia (ALI).

DATA SOURCES

PubMed, Embase, and the Cochrane Library.

REVIEW METHODS

A systematic search of PubMed, Embase, and the Cochrane Library was performed to identify observational studies and trials published between 1990 and 2022 reporting on the results of CDT in patients with Rutherford I ALI. A meta-analysis was performed using a random effects model with 95% confidence intervals (CIs). The outcomes of interests were treatment duration, angiographic success, bleeding complications, amputation and mortality rates, primary and secondary patency, and functional outcome expressed as pain free walking distance.

RESULTS

Thirty-nine studies were included, comprising 1 861 patients who received CDT for not immediately threatening ALI. Funnel plots showed an indication of publication bias, and heterogeneity was substantial. Data from 5 to 13 studies were included in the meta-analysis. The pooled treatment duration was 2 days (95% CI 1 - 2), with an angiographic success rate of 80% (95% CI 73 - 86) and a 30 day freedom of amputation rate of 98% (95% CI 92 - 100). The major bleeding rate was 5% (95% CI 2 - 14), with a 30 day mortality rate of 3% (95% CI 1 - 5). The amputation free survival rate was 71% (95% CI 62 - 80) at the one year and 63% (95% CI 51 - 73) at the three year follow up. Long term patency rates were retrieved from four studies: 48% at one year (95% CI 27 - 70). No data could be retrieved on patient walking distance.

CONCLUSION

Although CDT in the treatment of not immediately threatening ALI showed high angiographic success, the long term outcomes were relatively poor, with low patency and a substantial risk of major amputation. Further research is required to interpret the outcome of CDT in the context of potential confounders such as age and comorbidities.

Males and females have similar mortality after thoracic endovascular aortic repair for blunt thoracic aortic injury

OBJECTIVE

Prior literature has demonstrated worse outcomes for female patients after abdominal aortic aneurysm repair. Also, prior studies in the context of thoracic endovascular aneurysm repair (TEVAR) for thoracic aortic aneurysms have reported conflicting results regarding sex-related outcomes. Because the influence of sex on the outcomes after TEVAR for blunt thoracic aortic injuries (BTAIs) remains understudied, we evaluated the association between sex and outcomes after TEVAR for BTAI.

METHODS

We identified patients who had undergone TEVAR for BTAIs in the Vascular Quality Initiative registry from 2013 to 2022 and included those who had undergone TEVAR within zones 2 to 5 of the thoracic aorta. Patients with missing information regarding the aortic injury grade (Society for Vascular Surgery aortic injury grading system) were excluded. We performed multivariable logistic regression and Cox regression to determine the influence of sex on the perioperative outcomes and long-term mortality, respectively.

RESULTS

We identified 1311 patients, of whom 27% were female. The female patients were significantly older (female, 47 years [interquartile range (IQR), 30-63 years]; male, 38 years [IQR, 28-55 years]; P < .001) with higher rates of comorbidities. Although the female patients had had higher Glasgow coma scale scores (median, 15 [IQR, 11-15]; vs 14 [IQR, 8-15]; P = .028), no differences were found in the aortic injury grade or other coexisting traumatic injuries between the sexes. Apart from the longer procedure duration for the female patients (median, 79 minutes [IQR, 52-119 minutes]; vs 69 minutes [IQR, 48-106 minutes]; P = .008), the procedural characteristics were comparable. After adjustment, no significant association was found between female sex and perioperative mortality (7.1% vs 8.1%; odds ratio, 0.76; 95% confidence interval [CI], 0.43-1.3; P = .34). The male and female patients had had comparable rates of postoperative complications (26% vs 29%; odds ratio, 0.89; 95% CI: 0.52-1.5]; P = .26) including access-related complications (0.5% vs 0.8%; P=.83). However, females had a significantly higher risk for reintervention during the index admission (odds ratio, 2.5; 95% CI, 1.1-5.5; P = .024). No significant difference was found between the male and female patients with respect to 5-year mortality (hazard ratio, 0.87; 95% CI, 0.57-1.35; P = .50).

CONCLUSIONS

Unlike the sex-based outcome disparities observed after thoracic aortic aneurysm repair, we found no significant association between sex and perioperative outcomes or long-term mortality after TEVAR for BTAIs. This contrast in the sex-related outcomes after other vascular pathologies might be explained by differences in the pathology, demographics, and anatomic factors in these patients.

Vascular e-Learning in the MENA Region during the COVID-19 Pandemic

<b><i>Introduction:</i></b> With the steady rise in interest in e-learning and the sudden boost provoked by the COVID-19 pandemic, it becomes necessary to explore the e-learning experience within the medical community in the MENA region. <b><i>Methods:</i></b> An online survey was conducted during the early phase of the COVID-19 pandemic (June 15 – October 15, 2020). <b><i>Results:</i></b> Seventy-eight vascular surgeons and trainees from 16 countries participated. 88% of the participants were male. 55% attended more than 4 activities. More than half of the activities did not lead to any official certification. Topic was the primary determinant for attending an activity. National societies and social media played a major role in disseminating activity-related information. Lack of time, increased workload, differences in time zone, and technical issues were the main obstacles cited. 84.7% of the participants had a positive impression. <b><i>Conclusion:</i></b> As the COVID-19 pandemic boosted e-learning activities in vascular surgery, a shift was observed in the learning mode and new leadership skills were called upon. Novel ways of quality control are required.

Major Bleeding During Thrombolytic Therapy for Acute Lower Limb Ischaemia: Value of Laboratory Tests for Clinical Decision Making, 17 Years of Experience

OBJECTIVE

Regular measurement of fibrinogen as dose guidance in catheter directed thrombolysis (CDT) for acute limb ischaemia (ALI) has recently been dropped from European guidelines based on inconsistent literature. This study aimed to determine whether low fibrinogen levels and high activated partial thromboplastin time (APTT) are associated with an increased major bleeding risk during CDT.

METHODS

All consecutive patients treated with CDT for ALI in two Dutch hospitals between January 2004 and April 2021 were analysed retrospectively. Patients were treated with two dosing regimens (low dose: 50 000 IU/hour; high dose: 100 000 IU/hour) of urokinase and, after 2018, with a single low dose regimen of alteplase (rtPA) due to urokinase manufacturing problems. The incidence of major bleeding and associated APTT and fibrinogen levels were reviewed from patient charts.

RESULTS

Of the 443 included cases, 277 underwent CDT with urokinase and 166 with rtPA. The incidence of major bleeding in the whole cohort was 7%. Patients with a fibrinogen levels < 1.0 g/L developed more major bleeding than those in whom the fibrinogen level did not drop below 1.0 g/L (15% vs. 6%; p = .041). Systemic heparinisation during CDT or high (> 80 seconds) APTT were not significantly associated with major bleeding. Angiographic success (47% vs. 72%; p = .003) and 30 day amputation free survival (53% vs. 82%; p < .001) were lower for cases with major bleeding. Older age (odds ratio [OR] 1.06, 95% confidence interval [CI] 1.02 - 1.11), cardiac history (OR 3.35, 95% CI 1.39 - 8.06), high dose regimens (≥ 75 000 IU/hour urokinase; OR 2.67, 95% CI 1.18 - 6.04), and fibrinogen values < 1.0 g/L (OR 5.59, 95% CI 1.98 - 15.77) were independent predictors for major bleeding during CDT.

CONCLUSION

High dose thrombolytic regimens and fibrinogen levels of ≤ 1.0 g/L are associated with more major bleeding during thrombolytic therapy. Major bleeding significantly worsened the clinical outcome. A prospective comparative study is needed to assess the benefit of monitoring fibrinogen levels.

Editor's Choice - Sex Differences in Response to Administration of Heparin During Non-Cardiac Arterial Procedures

OBJECTIVE

Females are more prone to complications during non-cardiac arterial procedures (NCAPs) than males. The current study investigated the difference in the effect of peri-procedural prophylactic heparin in males and females, using the activated clotting time (ACT). This was a retrospective analysis of a prospective multicentre cohort study.

METHODS

All patients undergoing elective NCAP using heparin and ACT measurements between January 2016 and March 2020 were included. Two heparin dosage protocols were used: weight based dosing of 100 IU/kg (international units per kilogram) or a bolus of 5 000 IU. The primary outcome was the anticoagulatory effect of heparin after five minutes, measured by ACT. Secondary outcomes were the effect of heparin after 30 minutes, bleeding complications, and arterial thromboembolic complications (ATECs).

RESULTS

A total of 778 patients were included; 26% were female. After 100 IU/kg (n = 300), females more often reached longer ACT (< 200 seconds: 22% vs. 25%, p = .62; 200 - 250 seconds: 41% vs. 53%, p = .058; 251 - 280 seconds, 26% vs. 15%, p = .030). The mean ACT after 100 IU/kg heparin was 233 seconds (95% confidence interval [CI] 224 - 243) for females and 226 seconds (95% CI 221 - 231) for males (p = .057). After a bolus of 5 000 IU of heparin (n = 411), females reached significantly higher levels of anticoagulation than males (mean ACT 204 seconds vs. 190 seconds: p ≤ .001; ACT < 200 seconds: 44% vs. 66%; p < .001; ACT 200 - 250 seconds: 47% vs. 30%, p = .001; ACT 251 - 280 seconds: 7.8% vs. 2.3%, p = .009). Thirty minutes after heparin administration, 58% of all patients had an ACT < 200 seconds. ATECs did not differ between females and males (6.9% vs. 5.1%, p = .33) but bleeding complications were higher in females (27% vs. 16%, p = .001).

CONCLUSION

Heparin leads to significantly longer ACT in females during NCAP. Further research is needed to investigate whether individually based heparin protocols lead to fewer bleeding complications and lower incidence of ATECs.

Feasibility of Microbubble-Accelerated Low-Dose Thrombolysis of Peripheral Arterial Occlusions Using an Ultrasound Catheter

PURPOSE

Intra-arterial administration of microbubbles (MBs) through an ultrasound (US) catheter increases the local concentration of MBs into the thrombus and may further enhance outcomes of contrast-enhanced sonothrombolysis (CEST). The objective of this study was to evaluate the feasibility and lytic efficacy of intra-arterial infusion of MBs during US-enhanced thrombolysis in both in vitro and in vivo peripheral arterial occluded models.

MATERIALS AND METHODS

SonoVue and Luminity MBs were infused at a flow rate of 20 mL/h through either the drug delivery lumen of the US catheter (DDC, n=20) or through the tube lumen of the vascular phantom (systematic infusion, n=20) during thrombolysis with a low-dose urokinase (UK) protocol (50 000 IU/h) with(out) US application to assess MB survivability and size by pre-treatment and post-treatment measurements. A human thrombus was placed into a vascular phantom of the flow system to examine the lytic effects of CEST by post-treatment D-dimer concentrations measurements of 5 treatment conditions (saline, UK, UK+US, UK+US+SonoVue, and UK+US+Luminity). Thrombolytic efficacy of localized MBs and US delivery was then investigated in vivo in 5 porcine models by arterial blood flow, microcirculation, and postmortem determined thrombus weight and remaining length.

RESULTS

US exposure significantly decreased SonoVue (p=0.000) and Luminity (p=0.000) survivability by 37% and 62%, respectively. In vitro CEST treatment resulted in higher median D-dimer concentrations for the SonoVue (0.94 [0.07-7.59] mg/mL, p=0.025) and Luminity (0.83 [0.09-2.53] mg/mL, p=0.048) subgroups when compared with thrombolysis alone (0.36 [0.02-1.00] mg/mL). The lytic efficacy of CEST examined in the porcine model showed an improved median arterial blood flow of 21% (7%-79%), and a median thrombus weight and length of 1.02 (0.96-1.43) g and 2.25 (1.5-4.0) cm, respectively. One allergic reaction and 2 arrhythmias were observed due to the known allergic reaction on lipids in the porcine model.

CONCLUSION

SonoVue and Luminity can be combined with an US catheter and could potentially accelerate thrombolytic treatment of peripheral arterial occlusions.

CLINICAL IMPACT

Catheter-directed thrombolysis showed to be an effective alternative to surgery for acute peripheral arterial occlusions, but this technique is still associated with several limb and life-threatening complications. The effects of thrombolysis on clot dissolution may be further enhanced by intra-arterial administration of microbubbles through an ultrasound catheter. This study demonstrates the feasibility and lytic efficacy of intra-arterial infusion of microbubbles during US-enhanced thrombolysis in both in vitro and in vivo peripheral arterial occluded models.

Editor's Choice - Update of the European Society for Vascular Surgery (ESVS) 2020 Clinical Practice Guidelines on the Management of Acute Limb Ischaemia in Light of the COVID-19 Pandemic, Based on a Scoping Review of the Literature

OBJECTIVE

To perform a scoping review of how patients with COVID-19 are affected by acute limb ischaemia (ALI) and evaluate the recommendations of the 2020 ESVS ALI Guidelines for these patients.

METHODS

Research questions were defined, and a systematic literature search was performed following the PRISMA guidelines. Abstracts and unpublished literature were not included. The definition of ALI in this review is in accordance with the ESVS guidelines.

RESULTS

Most identified papers were case reports or case series, although population based data and data from randomised controlled trials were also identified. In total, 114 unique and relevant papers were retrieved. Data were conflicting concerning whether the incidence of ALI increased, or remained unchanged, during the pandemic. Case reports and series reported ALI in patients who were younger and healthier than usual, with a greater proportion affecting the upper limb. Whether or not this is coincidental remains uncertain. The proportion of men/women affected seems unchanged. Most reported cases were in hospitalised patients with severe COVID-19. Patients with ALI as their first manifestation of COVID-19 were reported. Patients with ALI have a worse outcome if they have a simultaneous COVID-19 infection. High levels of D-dimer may predict the occurrence of arterial thromboembolic events in patients with COVID-19. Heparin resistance was observed. Anticoagulation should be given to hospitalised COVID-19 patients in prophylactic dosage. Most of the treatment recommendations from the ESVS Guidelines remained relevant, but the following were modified regarding patients with COVID-19 and ALI: 1) CTA imaging before revascularisation should include the entire aorta and iliac arteries; 2) there should be a high index of suspicion, early testing for COVID-19 infection and protective measures are advised; and 3) there should be preferential use of local or locoregional anaesthesia during revascularisation.

CONCLUSION

Although the epidemiology of ALI has changed during the pandemic, the recommendations of the ESVS ALI Guidelines remain valid. The above mentioned minor modifications should be considered in patients with COVID-19 and ALI.

ACTION-1: study protocol for a randomised controlled trial on ACT-guided heparinization during open abdominal aortic aneurysm repair

BACKGROUND

Heparin is used worldwide for 70 years during all non-cardiac arterial procedures (NCAP) to reduce thrombo-embolic complications (TEC). But heparin also increases blood loss causing possible harm for the patient. Heparin has an unpredictable effect in the individual patient. The activated clotting time (ACT) can measure the effect of heparin. Currently, this ACT is not measured during NCAP as the standard of care, contrary to during cardiac interventions, open and endovascular. A RCT will evaluate if ACT-guided heparinization results in less TEC than the current standard: a single bolus of 5000 IU of heparin and no measurements at all. A goal ACT of 200-220 s should be reached during ACT-guided heparinization and this should decrease (mortality caused by) TEC, while not increasing major bleeding complications. This RCT will be executed during open abdominal aortic aneurysm (AAA) surgery, as this is a standardized procedure throughout Europe.

METHODS

Seven hundred fifty patients, who will undergo open AAA repair of an aneurysm originating below the superior mesenteric artery, will be randomised in 2 treatment arms: 5000 IU of heparin and no ACT measurements and no additional doses of heparin, or a protocol of 100 IU/kg bolus of heparin and ACT measurements after 5 min, and then every 30 min. The goal ACT is 200-220 s. If the ACT after 5 min is < 180 s, 60 IU/kg will be administered; if the ACT is between 180 and 200 s, 30 IU/kg. If the ACT is > 220 s, no extra heparin is given, and the ACT is measured after 30 min and then the same protocol is applied. The expected incidence for the combined endpoint of TEC and mortality is 19% for the 5000 IU group and 11% for the ACT-guided group.

DISCUSSION

The ACTION-1 trial is an international RCT during open AAA surgery, designed to show superiority of ACT-guided heparinization compared to the current standard of a single bolus of 5000 IU of heparin. A significant reduction in TEC and mortality, without more major bleeding complications, must be proven with a relevant economic benefit. TRIAL REGISTRATION {2A}: NTR NL8421 ClinicalTrials.gov NCT04061798 . Registered on 20 August 2019 EudraCT 2018-003393-27 TRIAL REGISTRATION: DATA SET {2B}: Data category Information Primary registry and trial identifying number ClinicalTrials.gov : NCT04061798 Date of registration in primary registry 20-08-2019 Secondary identifying numbers NTR: NL8421 EudraCT: 2018-003393-27 Source(s) of monetary or material support ZonMw: The Netherlands Organisation for Health Research and Development Dijklander Ziekenhuis Amsterdam UMC Primary sponsor Dijklander Ziekenhuis Secondary sponsor(s) N/A Contact for public queries A.M. Wiersema, MD, PhD Arno@wiersema.nu 0031-229 208 206 Contact for scientific queries A.M. Wiersema, MD, PhD Arno@wiersema.nu 0031-229 208 206 Public title ACT Guided Heparinization During Open Abdominal Aortic Aneurysm Repair (ACTION-1) Scientific title ACTION-1: ACT Guided Heparinization During Open Abdominal Aortic Aneurysm Repair, a Randomised Trial Countries of recruitment The Netherlands. Soon the recruitment will start in Germany Health condition(s) or problem(s) studied Abdominal aortic aneurysm, arterial disease, surgery Intervention(s) ACT-guided heparinization 5000 IU of heparin Key inclusion and exclusion criteria Ages eligible for the study: ≥18 years Sexes eligible for the study: both Accepts healthy volunteers: no Inclusion criteria: Study type Interventional Allocation: randomized Intervention model: parallel assignment Masking: single blind (patient) Primary purpose: treatment Phase IV Date of first enrolment March 2020 Target sample size 750 Recruitment status Recruiting Primary outcome(s) The primary efficacy endpoint is 30-day mortality and in-hospital mortality during the same admission. The primary safety endpoint is the incidence of bleeding complications according to E-CABG classification, grade 1 and higher. Key secondary outcomes Serious complications as depicted in the Suggested Standards for Reports on Aneurysmal disease: all complications requiring re-operation, longer hospital stay, all complications.

Vascular e-Learning During the COVID-19 Pandemic: The EL-COVID Survey

BACKGROUND

The corona virus disease (COVID-19) pandemic has radically changed the possibilities for vascular surgeons and trainees to exchange knowledge and experience. The aim of the present survey is to inventorize the e-learning needs of vascular surgeons and trainees as well as the strengths and weaknesses of vascular e-Learning.

METHODS

An online survey consisting of 18 questions was created in English, with a separate bilingual English-Mandarin version. The survey was dispersed to vascular surgeons and trainees worldwide through social media and via direct messaging from June 15, 2020 to October 15, 2020.

RESULTS

Eight hundred and fifty-six records from 84 different countries could be included. Most participants attended several online activities (>4: n = 461, 54%; 2-4: n = 300, 35%; 1: n = 95, 11%) and evaluated online activities as positive or very positive (84.7%). In deciding upon participation, the topic of the activity was most important (n = 440, 51.4%), followed by the reputation of the presenter or the panel (n = 178, 20.8%), but not necessarily receiving accreditation or certification (n = 52, 6.1%). The survey identified several shortcomings in vascular e-Learning during the pandemic: limited possibility to attend due to lack of time and increased workload (n = 432, 50.5%), no protected/allocated time (n = 488, 57%) and no accreditation or certification, while technical shortcomings were only a minor problem (n = 25, 2.9%).

CONCLUSIONS

During the COVID-19 pandemic vascular e-Learning has been used frequently and was appreciated by vascular professionals from around the globe. The survey identified strengths and weaknesses in current e-Learning that can be used to further improve online learning in vascular surgery.

Microbubbles and Ultrasound Accelerated Thrombolysis for Peripheral Arterial Occlusions: The Outcomes of a Single Arm Phase II Trial

OBJECTIVE

Acute peripheral arterial occlusions can be treated by catheter directed thrombolysis (CDT). However, CDT is time consuming and accompanied by the risk of bleeding complications. The addition of contrast enhanced ultrasound and microbubbles could improve thrombus susceptibility to thrombolytic agents and potentially shorten treatment time with a lowered risk of bleeding complications. This article reports the outcomes of the safety and feasibility of this novel technique.

METHODS

In this single arm phase II trial, 20 patients with acute lower limb ischaemia received CDT combined with an intravenous infusion of microbubbles and locally applied ultrasound during the first hour of standard intra-arterial thrombolytic therapy. The primary endpoint was safety, i.e., occurrence of serious adverse events (haemorrhagic complications and/or amputation) and death within one year. Secondary endpoints included angiographic and clinical success, thrombolysis duration, additional interventions, conversion, and quality of life.

RESULTS

The study included 20 patients (16 men; median age 68.0 years; range, 50.0 - 83.0; and 40% native artery and 60% bypass graft). In all patients, the use of microbubble contrast enhanced sonothrombolysis could be applied successfully. There were no serious adverse events related to the experimental treatment. Duplex examination showed flow distal from the occlusion after 23.1 hours (range 3.1 - 46.5) with a median thrombolysis time of 47.5 hours (range 6.0 - 81.0). The short term ABI and pain scores significantly improved; however, no changes were observed before or after thrombolysis in the microcirculation. Overall mortality and amputation rates were both 2% within one year. The one year patency rate was 55%.

CONCLUSION

Treatment of patients with acute peripheral arterial occlusions with contrast enhanced sonothrombolysis is feasible and safe to perform in patients. Further research is necessary to investigate the superiority of this new treatment over standard treatment.

Robot-assisted transthoracic first rib resection for venous thoracic outlet syndrome

BACKGROUND

Venous thoracic outlet syndrome (vTOS) is caused by external compression of the subclavian vein at the costoclavicular junction. It can be subdivided in McCleery Syndrome and Paget-Schroetter Syndrome (PSS). To improve the venous outflow of the arm and to prevent recurrent thrombosis, first rib resection with venolysis of the subclavian vein can be performed. Open transaxillary, supraclavicular, infraclavicular or combined paraclavicular approaches are well known, but more recent robot-assisted techniques are introduced. We report our short- and long-term results of a minimal invasive transthoracic approach for resection of the anteromedial part of the first rib using the DaVinci surgical robot, performed through three trocars.

METHODS

We analyzed all patients with vTOS who were scheduled to undergo robot-assisted transthoracic first rib resection in the period July 2012 to May 2016. Outcomes were: technical success, operation time, blood loss, hospital stay, 30-day complications and patency. Functional outcomes were assessed using the "Disability of the Arm, Shoulder and Hand" (DASH) questionnaire.

RESULTS

Fifteen patients (8 male, 7 female; mean age 32.9 years, range 20-54 years) underwent robot-assisted transthoracic first rib resection. Conversion to transaxillary resection was necessary in three patients. Average operation time was 147.9 min (range 88-320 min) with a mean blood loss of 79.5 cc (range 10-550 cc). Mean hospital stay was 3.5 days (range 2-9). In three patients, complications were reported (Clavien-Dindo grade 2-3a). Patency was 91% at 15.5 months' follow-up. DASH scores at one and three years showed excellent functional outcomes (7.1 (SD= 6.9, range 0-20.8) and 6.0 (SD= 6.4, range 0-25)) and are comparable to the scores of the normative general population.

CONCLUSION

Robot-assisted transthoracic first rib resection with only three trocars is a feasible minimal invasive approach for first rib resection in the management of vTOS. This technique enables the surgeon to perform venolysis under direct 3D vision with good patency and long-term functional outcome. Studies with larger cohort size are needed to compare the outcomes of this robot-assisted technique with other more established approaches.

Survival and Living Situation After Ruptured Abdominal Aneurysm Repair in Octogenarians

OBJECTIVE

To determine the 30 day and one year mortality and post-operative living situation in octogenarians treated for ruptured abdominal aortic aneurysm (rAAA).

METHODS

A retrospective study was performed at four centres in the Netherlands. All consecutive patients aged ≥80 years, presenting with a rAAA between January 2013 and October 2018, were included. The primary outcomes were post-operative living situation and one year mortality.

RESULTS

In total, 157 patients were included. Forty-seven received palliative care and 110 patients had surgery. After endovascular or open repair, the one year mortality rate was 50.0%. The 30 day mortality rate was 40.8% (95% confidence interval [CI] 27-55) and 31.7% (95% CI 20-44), for endovascular and open repair, respectively (p = .32). Sixty-five per cent of survivors were discharged home, while 34.8% went to a nursing home for rehabilitation. Of the surviving patients, 82.6% went back to living in their pre-rupture home situation. Of the investigated variables, only a high body mass index proved a significant predictor of death at 30 days and one year. Compared with operated patients, patients turned down for surgery were older (mean age 87.5 ± 3.8 vs. 84.0 ± 3.5; p < .001), lived significantly more often in a nursing home (odds ratio 1.02, 95% CI 1.00-1.03; p < .001), were more often dependent (odds ratio 3.69, 95% CI 2.31-5.88; p < .001) and had a lower Glasgow Coma Scale score on arrival (odds ratio 0.42, 95% CI 0.25-0.69; p = .002). All palliative patients died within three days.

CONCLUSION

Overall treatment outcomes showed that octogenarians should not be denied surgery based on age alone, as half of the octogenarians that undergo surgical treatment are still alive one year after rAAA repair. In addition, > 80% returned to their own home after rehabilitation.

Editor's Choice - Nationwide Analysis of Patients Undergoing Iliac Artery Aneurysm Repair in the Netherlands

OBJECTIVE

The new 2019 guideline of the European Society for Vascular Surgery (ESVS) recommends consideration for elective iliac artery aneurysm (eIAA) repair when the iliac diameter exceeds 3.5 cm, as opposed to 3.0 cm previously. The current study assessed diameters at time of eIAA repair and ruptured IAA (rIAA) repair and compared clinical outcomes after open surgical repair (OSR) and endovascular aneurysm repair (EVAR).

METHODS

This retrospective observational study used the nationwide Dutch Surgical Aneurysm Audit (DSAA) registry that includes all patients who undergo aorto-iliac aneurysm repair in the Netherlands. All patients who underwent primary IAA repair between 1 January 2014 and 1 January 2018 were included. Diameters at time of eIAA and rIAA repair were compared in a descriptive fashion. The anatomical location of the IAA was not registered in the registry. Patient characteristics and outcomes of OSR and EVAR were compared with appropriate statistical tests.

RESULTS

The DSAA registry comprised 974 patients who underwent IAA repair. A total of 851 patients were included after exclusion of patients undergoing revision surgery and patients with missing essential variables. eIAA repair was carried out in 713 patients, rIAA repair in 102, and symptomatic IAA repair in 36. OSR was performed in 205, EVAR in 618, and hybrid repairs and conversions in 28. The median maximum IAA diameter at the time of eIAA and rIAA repair was 43 (IQR 38-50) mm and 68 (IQR 58-85) mm, respectively. Mortality was 1.3% (95% CI 0.7-2.4) after eIAA repair and 25.5% (95% CI 18.0-34.7) after rIAA repair. Mortality was not significantly different between the OSR and EVAR subgroups. Elective OSR was associated with significantly more complications than EVAR (intra-operative: 9.8% vs. 3.6%, post-operative: 34.0% vs. 13.8%, respectively).

CONCLUSION

In the Netherlands, most eIAA repairs are performed at diameters larger than recommended by the ESVS guideline. These findings appear to support the recent increase in the threshold diameter for eIAA repair.

Cold Renal Perfusion During Simulation of Juxtarenal Aortic Aneurysm Repair Reduces Systemic Oxidative Stress and Sigmoid Damage in Rats

OBJECTIVES

Juxtarenal aortic surgery induces renal ischaemia reperfusion, which contributes to systemic inflammatory tissue injury and remote organ damage. Renal cooling during suprarenal cross clamping has been shown to reduce renal damage. It is hypothesised that renal cooling during suprarenal cross clamping also has systemic effects and could decrease damage to other organs, like the sigmoid colon.

METHODS

Open juxtarenal aortic aneurysm repair was simulated in 28 male Wistar rats with suprarenal cross clamping for 45 min, followed by 20 min of infrarenal aortic clamping. Four groups were created: sham, no, warm (37 °C saline), and cold (4 °C saline) renal perfusion during suprarenal cross clamping. Primary outcomes were renal damage and sigmoid damage. To assess renal damage, procedure completion serum creatinine rises were measured. Peri-operative microcirculatory flow ratios were determined in the sigmoid using laser Doppler flux. Semi-quantitative immunofluorescence microscopy was used to measure alterations in systemic inflammation parameters, including reactive oxygen species (ROS) production in circulating leukocytes and leukocyte infiltration in the sigmoid. Sigmoid damage was assessed using digestive enzyme (intestinal fatty acid binding protein - I-FABP) leakage, a marker of intestinal integrity.

RESULTS

Suprarenal cross clamping caused deterioration of all systemic parameters. Only cold renal perfusion protected against serum creatinine rise: 0.45 mg/dL without renal perfusion, 0.33 mg/dL, and 0.14 mg/dL (p = .009) with warm and cold perfusion, respectively. Microcirculation in the sigmoid was attenuated with warm (p = .002) and cold renal perfusion (p = .002). A smaller increase of ROS production (p = .034) was seen only after cold perfusion, while leukocyte infiltration in the sigmoid colon decreased after warm (p = .006) and cold perfusion (p = .018). Finally, digestive enzyme leakage increased more without (1.5AU) than with warm (1.3AU; p = .007) and cold renal perfusion (1.2AU; p = .002).

CONCLUSIONS

Renal ischaemia/reperfusion injury after suprarenal cross clamping decreased microcirculatory flow, increased systemic ROS production, leukocyte infiltration, and I-FABP leakage in the sigmoid colon. Cold renal perfusion was superior to warm perfusion and reduced renal damage and had beneficial systemic effects, reducing sigmoid damage in this experimental study.

Prediction of Survival after 48 Hours of Intensive Unit Care following Repair of Ruptured Abdominal Aortic Aneurysm-Multicentric Study for External Validation of a New Prediction Score for 30-Day Mortality

BACKGROUND

Ruptured abdominal aortic aneurysm (rAAA) remains a critical life-threatening condition. We aimed to evaluate rAAA management in our center focusing on predictors of mortality at 48 hr of intensive care unit (ICU) and to develop a new mortality prediction score considering data at 48 hr postprocedure. External validation of the modified score with patient data from independent vascular surgery centers was subsequently pursued.

METHODS

Clinical data of all patients admitted in our center from January 2010 to December 2017 with the diagnosis of rAAA were retrospectively reviewed for the development of the mortality prediction score. Subsequently, clinical data from patients admitted at independent centers from January 2010 to December 2017 were reviewed for external validation of the score. Statistical analysis was performed with SPSS Version 25.

RESULTS

A total of 78 patients were included in the first part of the study: 21 endovascular aneurysm repairs (EVARs), 56 open repairs (ORs), and 1 case of conservative management. Intraoperative mortality in EVAR and OR groups was 0% vs. 24.6%, respectively (P = 0.012). Thirty-day mortality reached 50% and 33% in the OR and EVAR groups. For patients alive at 48 hr, 30-day mortality diminished to 27.6%. Several preoperative predictors of outcome were identified: smoking (P = 0.004), hemodynamic instability(P = 0.004), and elevated international normalized ratio (P < 0.0001). Dutch Aneurysm Score and Vascular Study Group of New England Score (VSGNE) were also significant predictors of outcome (area under the receiver operating characteristic curve [ROC AUC] 0.89 and 0.79, respectively; P < 0.0001). At 48 hr of ICU stay, high lactate level, high Sequential Organ Failure Assessment score, need for hemodyalitic technique, and hemodynamic instability were significant risk predictors for 30-day mortality (P < 0.05). VSGNE score was modified with the inclusion of 2 variables: hemodynamic instability and lactate level at 48 hr and a new score was attained-Postoperative Aneurysm Score (PAS). Comparing AUC for VSGNE and PAS for patients alive at 48 hr, the latter was significantly better (AUC 0.775 vs. 0.852, P = 0.039). The PAS was applied and validated in 3 independent vascular surgery centers (AUC VSGNE 0.782 vs. AUC PAS 0.820, P = 0.027).

CONCLUSIONS

Despite recent evidence on preoperative predictors of survival in an era when both EVAR and OR are available, emergent decision to withhold life-saving treatment will always be extremely difficult. Therefore, the policy in our department is to try surgical repair in all cases. It remains important, however, to identify whether late deaths can be predicted, so that unnecessary prolonged treatment can be avoided. A PAS was delineated predicting 30-day mortality significantly better in patients alive at 48 hr. The score was externally applied and validated in independent centers, corroborating the score's usefulness.

Secondary Fill Minimizes Gutter Size in Chimney EVAS Configurations In Vitro

Purpose: To investigate in an in vitro model if secondary endobag filling can reduce gutter size during chimney endovascular aneurysm sealing (chEVAS). Materials and Methods: Nellix EVAS systems were deployed in 2 silicone juxtarenal aneurysm models with suprarenal aortic diameters of 19 and 24 mm. Four configurations were tested: EVAS with 6-mm balloon-expandable (BE) or self-expanding (SE) chimney grafts (CGs) in the renal branches of both models. Balloons were inflated simultaneously in the CGs and main endografts during primary and secondary endobag filling and polymer curing. Computed tomography (CT) was performed immediately after the primary and secondary fills. Cross-sectional lumen areas were measured on the CT images to calculate gutter volumes and percent change. CG compression was calculated as the reduction in lumen surface area measured perpendicular to the central lumen line. The largest gutter volume and highest compression were presented per CG configuration per model. Results: Secondary endobag filling reduced the largest gutter volumes from 99.4 to 73.1 mm³ (13.2% change) and 84.2 to 72.0 mm³ (27.6% change) in the BECG configurations and from 67.2 to 44.0 mm³ (34.5% change) and 92.7 to 82.3 mm³ (11.2% change) in the SECG configurations in the 19- and 24-mm models, respectively. Secondary endobag filling increased CG compression in 6 of 8 configurations. BECG compression changed by −0.2% and 5.4% and by −1.0% and 0.4% in the 19- and 24-mm models, respectively. SECG compression changed by 10.2% and 16.0% and by 7.2% and 7.3% in the 19- and 24-mm models, respectively. Conclusion: Secondary endobag filling reduced paragraft gutters; however, this technique did not obliterate them. Increased CG compression and prolonged renal ischemia time should be considered if secondary endobag filling is used.

Efficacy versus Complications in Arterial Thrombolysis

BACKGROUND

Acute peripheral arterial occlusions threaten life and limb. Thrombolysis is an established, minimally invasive alternative treatment for surgical thromboembolectomy. Yet, there is no consensus regarding an optimal thrombolysis protocol, and current knowledge is largely based on studies from the 1990s. This study reviews a contemporary cohort of patients treated with thrombolysis and aims to evaluate the treatment results and to identify possible predictors for outcome and (bleeding) complications.

METHODS

The electronic health record data of all consecutive patients who underwent thrombolysis for acute limb ischemia due to thromboembolic lower extremity arterial occlusions between April 2006 and June 2012 were analyzed. End points were change in clinical stage of ischemia, incidence of bleeding complications, duration of thrombolysis, predictors of outcome and complications, and mortality and amputation-free rates after 30-day and 6-months follow-up.

RESULTS

In total, 109 cases were included. Clinical improvement was observed in 79%. Amputation-free rates at 30 days and 6 months were 94% and 90%, respectively. The incidence of major bleeding complications was 13%. Median duration of thrombolysis was 27 (4-68) hr. Mortality rates at 30 days and 6 months were 7% and 16%, respectively; none bleeding related. In addition to age, popliteal artery occlusions and a progressed chronic vascular stage are predictive for a worse outcome. Age, female sex, and cardiac history were risk factors for bleeding.

CONCLUSIONS

Treatment of peripheral arterial occlusions with high-dose thrombolysis on an intensive-care unit yields high clinical success rates, but major bleeding complications are often observed. Strict clinical observation remains essential since intensive monitoring of hemostatic parameters during thrombolysis does not predict bleeding complications.

Thoracic sympathectomy for upper extremity ischemia

INTRODUCTION

Thoracic sympathectomy is performed in the management of a variety of disorders of the upper extremity. To evaluate the contemporary results of thoracic sympathectomy for upper extremity ischemia a systematic review of the literature was conducted.

EVIDENCE AQUISITION

We performed a PubMed, EMBASE and Cochrane search of the literature written in the English language from January 1975 to December 2015. All articles presenting original patient data regarding the effect of treatment on symptoms or on the healing of ulcers were eligible for inclusion. Individual analyses for Primary Raynaud's Disease (PRD) and Secondary Raynaud's Phenomenon (SRP) were performed.

EVIDENCE SYNTHESIS

We included 6 prospective and 23 retrospective series with a total of 753 patients and 1026 affected limbs. Early beneficial effects of thoracic sympathectomy were noticed in 63-100% (median 94%) of all patients, in 73-100% (median 98%) of PRD patients and in 63-100% (median 94%) of SRP patients. The beneficial effect was noted to lessen over time. Long-term beneficial effects were reported in 13-100% (median 75%) of all patients, in 22-100% (median 58%) of PRD patients, and in 13-100% (median 79%) of SRD patients. Complete or improved ulcer healing was achieved in 33-100% and 25-67% respectively, of all patients.

CONCLUSIONS

Thoracic sympathectomy can be beneficial in the treatment of upper extremity ischemia in select patients. Although the effect in patients with PRD will lessen over time, it may still reduce the severity of symptoms. In SRD, effects are more often long-lasting. In addition, thoracic sympathectomy may maximize tissue preservation or prevent amputation in cases of digital ulceration.

Organ protection during aortic cross-clamping

Open surgical repair of an aortic aneurysm requires aortic cross-clamping, resulting in temporary ischemia of all organs and tissues supplied by the aorta distal to the clamp. Major complications of open aneurysm repair due to aortic cross-clamping include renal ischemia-reperfusion injury and postoperative colonic ischemia in case of supra- and infrarenal aortic aneurysm repair. Ischemia-reperfusion injury results in excessive production of reactive oxygen species and in oxidative stress, which can lead to multiple organ failure. Several perioperative protective strategies have been suggested to preserve renal function during aortic cross-clamping, such as pharmacotherapy and therapeutic hypothermia of the kidneys. In this chapter, we will briefly discuss the pathophysiology of ischemia-reperfusion injury and the preventative measures that can be taken to avoid abdominal organ injury. Finally, techniques to minimize the risk of complications during and after open aneurysm repair will be presented.

Prophylactic intraoperative antithrombotics in open infrainguinal arterial bypass surgery: a systematic review

Unfractionated heparin (UFH) is used intraoperatively as antithrombotic by most vascular surgeons worldwide during infrainguinal bypass surgery (IABS) to reduce the risk of peroperative and early graft thrombosis. To reduce the harmful side effects of UFH (bleeding complications, HIT) and to reduce peroperative and early graft failure, other pharmaceuticals have been suggested for IABS. A systematic review was performed using MEDLINE, EMBASE and Cochrane databases. Only 9 studies on IABS and intraoperative antithrombotic use were eligible for review. Between studies heterogeneity was high and investigated study populations were often of small size. No study was retrieved comparing UFH to no-UFH. Dextran, human antithrombin and iloprost showed no beneficial effect compared to UFH alone for patency, mortality and morbidity. Low molecular weight heparin (LMWH) has potential benefits compared to UFH, but a statistically significant effect could not be demonstrated from the current review. The use of UFH during IABS to prevent intraoperative graft thrombosis has not been proven in randomized clinical trials. Dextran, human antithrombin and iloprost showed to be of no added beneficial effect for the patient compared to UFH alone. Data on the use of LMWH instead of UFH are promising, but no statistically significant benefit could be reproduced from literature. Results from a recent Cochrane review were favourable for LMWH, but it appeared that included data were not complete in that review. Randomized controlled trials are required for intra-operative use of antithrombotics and to improve peroperative and early patency after IABS.

Mid-term results of robot-assisted laparoscopic surgery for aortoiliac occlusive disease

The aim of this study was to evaluate middle-term clinical results of robot-assisted laparoscopic surgery (RALS) to treat aortoiliac occlusive disease (AIOD). Between 2002 and 2007, 28 consecutive patients received robot-assisted laparoscopic aortobifemoral bypass grafting ( n = 24) or aortoiliac endarterectomy ( n = 4). Patients were followed prospectively. RALS could be completed successfully in 24 patients; conversion to open surgery was necessary in four patients (14%). Median operative time was 350 min. Median aortic clamping time was 70 min. Median hospital stay was five days. One patient died within 30 days. Non-lethal complications occurred in four patients (14%). Clinical symptoms improved in all patients. Primary and secondary limb-based patencies at 36 months were 89% and 91%, respectively. In conclusion, RALS is a feasible and durable technique for patients with AIOD. Although operative times are long, RALS allows rapid postoperative recovery.