Diagnostic accuracy of the maximal systolic acceleration to detect peripheral arterial disease.

BACKGROUND: Diagnosing peripheral arterial disease (PAD) can be challenging owing to medial arterial calcification (MAC) in patients with diabetes mellitus (DM) and chronic kidney disease (CKD). Current bedside tests, such as the ankle-brachial index and toe-brachial index, are often insufficient. The maximal systolic acceleration (ACCmax) is a velocimetric Doppler-derived parameter and could be a new promising test in the diagnostic workup of these patients. The primary aim of this study was to evaluate the diagnostic performance of the ACCmax to detect PAD. METHODS: A retrospective cohort study was performed in a tertiary referral hospital. Patients ≥18 years old with suspected PAD who underwent ACCmax measurement(s) along with computed tomography angiography of the abdominal aorta and lower extremities (reference test) were eligible for inclusion. ACCmax measurements of the posterior tibial artery, anterior tibial artery and peroneal artery were collected. Diagnostic performance was assessed by using sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and area under the curve (AUC). RESULTS: In total, 340 patients (618 limbs) were included. Approximately 40% suffered from DM and 30% had CKD. Diagnostic performance of the ACCmax to detect PAD for the posterior tibial artery showed a sensitivity of 90%, specificity of 93%, positive likelihood ratio of 12.83, and negative likelihood ratio of 0.11 (AUC, 0.953). For the anterior tibial artery, these results were 94%, 97%, 32.06, and 0.06 (same sequence as presented before) with an AUC of 0.984. The peroneal artery had a performance of 86%, 89%, 7.51, and 0.16, respectively (AUC, 0.893). Diagnostic accuracy of the ACCmax did not diminish in subgroup analysis for patients with DM or CKD. CONCLUSIONS: The ACCmax showed excellent diagnostic performance to detect PAD, independent of patients prone to medial arterial calcification.

Pilot Study on Feasibility and Outcome of a Nerve-Preserving Aortoiliac Exposure Technique.

BACKGROUND: Dysfunctional ejaculation is a common complication following open aortoiliac aneurysm surgery. It may occur in 49-63% of patients and is caused by iatrogenic damage to the sympathetic lumbar splanchnic nerves and superior hypogastric plexus. A nerve-preserving operative technique based on a unilateral right-sided approach to the abdominal aorta, was implemented in clinical practice. The aim of this pilot study was to establish the safety and feasibility of the technique, and whether a sympathetic pathway and ejaculatory function was preserved. METHODS: Patients were asked to fill out questionnaires preoperatively, and 6 weeks, 6 months, and 9 months postoperatively. The International Index of Erectile Function, Cleveland Clinic Incontinence Score (CCIS), Patient assessment of constipation symptoms (Pac-Sym), and International Consultation on Incontinence Questionnaire on male lower urinary tract symptoms were used. Surgeons were asked to complete a technical feasibility questionnaire. RESULTS: Twenty-four patients undergoing aortoiliac aneurysm surgery were included. The nerve-sparing phase of the procedure added an average of 5-10 min of operating time and was technically feasible in twenty-two patients. No major complications occurred during nerve-sparing exposure. Fifteen of twenty-four patients were sexually active at some point throughout the study. No postoperative loss of ejaculation was seen in sexually active patients. CCIS, Pac-sym, International Index of Erectile Function, and Incontinence Questionnaire on male lower urinary tract symptoms scores remained similar throughout the study. CONCLUSIONS: Nerve-preserving aortoiliac reconstruction surgery is safe and feasible. Ejaculatory function is preserved. Given the low number of patients in the study, further research is needed to provide robust data.

Perspectives of Patients and Professionals on Patient Education in Complex Endovascular Aortic Repair.

BACKGROUND: Misinterpretation of patient preferences in perioperative education can lead to an undesired treatment decision. This explorative interview study presents differences in perspectives of patients and professionals on patient education in complex endovascular aortic aneurysm management. METHODS: Using convenience sampling, a cross-sectional interview study was performed among patients who were in various stages of the decision-making process for complex endovascular aortic repair. Five physicians were interviewed, representing the main providers of clinical information. Interviews were transcribed verbatim and analyzed inductively. RESULTS: Twelve patients (mean age 76.6 [standard deviation: 6.4], 83% male) were interviewed. Ten (83%) felt like they had no other realistic option besides undergoing surgery, whereas all professionals (5/5) stressed the importance of delicate patient selection. Five patients out of 10 (50%) who commented on their preferred decisional role considered the professional's advice as decisive. All but 1 patient (11/12) reported that the information was easy to understand, whereas 4 out of 5 professionals (80%) doubted whether patients could fully comprehend everything. Patients experienced a lack of information on the recovery process, although professionals stated that this was addressed during consultation. CONCLUSIONS: Several differences were found in the perspectives of patients and professionals on education in complex aortic aneurysm management. In order to optimize patient involvement in decision-making, professionals should be aware of these possible discrepancies and address them during consultation. Future research could focus on these differences in more detail by including more patients depending on their treatment and decision stages.

Toward Uniform Case Identification Criteria in Observational Studies on Peripheral Arterial Disease: A Scoping Review.

BACKGROUND: The diagnosis of peripheral arterial disease (PAD) is commonly applied for symptoms related to atherosclerotic obstructions in the lower extremity, though its clinical manifestations range from an abnormal ankle-brachial index to critical limb ischemia. Subsequently, management and prognosis of PAD vary widely with the disease stage. A critical aspect is how this variation is addressed in administrative database-based studies that rely on diagnosis codes for case identification. The objective of this scoping review is to inventory the identification strategies used in studies on PAD that rely on administrative databases, to map the pros and cons of the International Classification of Diseases (ICD) codes applied, and to propose a first outline for a consensus framework for case identification in administrative databases. METHODS: Registry-based reports published between 2010 and 2021 were identified through a systematic PubMed search. Studies were subcategorized on the basis of the expressed study focus: claudication, critical limb ischemia, or general peripheral arterial disease, and the ICD code(s) applied for case identification mapped. RESULTS: Ninety studies were identified, of which 36 (40%) did not specify the grade of PAD studied. Forty-nine (54%) articles specified PAD grade studied. Five (6%) articles specified different PAD subgroups in methods and baseline demographics, but not in further analyses. Mapping of the ICD codes applied for case identification for studies that specified the PAD grade studied indicated a remarkable heterogeneity, overlap, and inconsistency. CONCLUSIONS: A large proportion of registry-based studies on PAD fail to define the study focus. In addition, inconsistent strategies are used for PAD case identification in studies that report a focus. These findings challenge study validity and interfere with inter-study comparison. This scoping review provides a first initiative for a consensus framework for standardized case selection in administrative studies on PAD. It is anticipated that more uniform coding will improve study validity and facilitate inter-study comparisons.

Persistent High Long-term Excess Mortality After Elective AAA Repair Especially in Women: A Large Population-based Study.

OBJECTIVE: The aim of this time-trend analysis is to estimate long-term excess mortality and associated cardiovascular risk for abdominal aortic aneurysm (AAA) patients after elective repair while addressing the changes in AAA management and patient selection over time. BACKGROUND: Despite the intensification of endovascular aneurysm repair and cardiovascular risk management, Swedish population data suggest that AAA patients retain a persistently high long-term mortality after elective repair. The question is whether this reflects suboptimal treatment, a changing patient population over time, or a national phenomenon. METHODS: Nationwide time-trend analysis including 40,730 patients (87% men) following elective AAA repair between 1995 and 2017. Three timeframes were compared, each reflecting changes in the use of endovascular aneurysm repair and intensification of cardiovascular risk management. Relative survival analyses were used to estimate disease-specific excess mortality. Competing risk of death analysis evaluated the risk of cardiovascular versus noncardiovascular death. Sensitivity analysis evaluated the impact of changes in patient selection over time. RESULTS: Short-term excess mortality significantly improved over time. Long-term excess mortality remained high with a doubled mortality risk for women (relative excess risk=1.87, 95% CI: 1.73-2.02). Excess mortality did not differ between age categories. The risk of cardiovascular versus noncardiovascular death remained similar over time, with a higher risk of cardiovascular death for women. Changes in patient population (ie, older and more comorbid patients in the latter period) marginally impacted excess mortality (2%). CONCLUSIONS: Despite changes in AAA care, patients retain a high long-term excess mortality after elective repair with a persistent high cardiovascular mortality risk. In this, a clear sex - but no age - disparity stands out.

Elastic Deformation Measurement Using Duplex Ultrasound for the Detection of High Aneurysm Sac Pressure Following EVAR.

PURPOSE: To describe the concept of aortic elastic deformation (ED) measurement using duplex ultrasonography (DUS) as a tool for detection of high aneurysm sac pressure following endovascular aortic repair (EVAR). TECHNIQUE: High aneurysm sac pressure, with or without proven endoleak, will result in a less compressible aneurysm. Using the dual image function in B-mode of the DUS device and a standardized amount of applied probe pressure, ED can be measured. It is defined as the percentage of deformation of the aneurysm sac on probe pressure application. We hypothesize that less ED of the aneurysm sac can be related with high aneurysm sac pressure and possibly the presence of clinically relevant endoleak. In this note, we describe the technical details of the procedure and report on the applicability and results of ED measurements in the framework of aortic aneurysm and EVAR follow-up in a cohort of 109 patients. CONCLUSION: ED measurement is the first noninvasive pressure-based method in the quest to find a practical and reliable diagnostic tool to exclude high aneurysm sac pressure. In our patient cohort, patients with proven endoleak showed a smaller ED (less compressible), implying the presence of high aneurysm sac pressure. Further research should confirm whether ED measurement using DUS could reliably exclude endoleak after EVAR and further explore its potential for clinical application in EVAR follow-up. CLINICAL IMPACT: For the first time, a simple, fast, and inexpensive diagnostic tool is presented in this study for detecting high sac pressure following EVAR. High sac pressure is typically caused by clinically significant endoleaks, which can have significant consequences. Currently, computed tomography scanning is the most common method used to identify and characterize endoleaks. However, measuring elastic deformation may potentially replace more invasive and expensive modalities, such as the computed tomography in the future.

Normalization of Time-Intensity Curves for Quantification of Foot Perfusion Using Near-Infrared Fluorescence Imaging With Indocyanine Green.

PURPOSE: Near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) is gaining popularity for the quantification of tissue perfusion, including foot perfusion in patients with lower extremity arterial disease (LEAD). However, the absolute fluorescence intensity is influenced by patient-and system-related factors limiting reliable and valid quantification. To enhance the quality of quantitative perfusion assessment using ICG NIR fluorescence imaging, normalization of the measured time-intensity curves seems useful. MATERIALS AND METHODS: In this cohort study, the effect of normalization on 2 aspects of ICG NIR fluorescence imaging in assessment of foot perfusion was measured: the repeatability and the region selection. Following intravenous administration of ICG, the NIR fluorescence intensity in both feet was recorded for 10 mins using the Quest Spectrum platform®. The effect of normalization on repeatability was measured in the nontreated foot in patients undergoing unilateral revascularization preprocedural and postprocedural (repeatability group). The effect of normalization on region selection was performed in patients without LEAD (region selection group). Absolute and normalized time-intensity curves were compared. RESULTS: Successful ICG NIR fluorescence imaging was performed in 54 patients (repeatability group, n = 38; region selection group, n = 16). For the repeatability group, normalization of the time-intensity curves displayed a comparable inflow pattern for repeated measurements. For the region selection group, the maximum fluorescence intensity (Imax) demonstrated significant differences between the 3 measured regions of the foot (P = .002). Following normalization, the time-intensity curves in both feet were comparable for all 3 regions. CONCLUSION: This study shows the effect of normalization of time-intensity curves on both the repeatability and region selection in ICG NIR fluorescence imaging. The significant difference between absolute parameters in various regions of the foot demonstrates the limitation of absolute intensity in interpreting tissue perfusion. Therefore, normalization and standardization of camera settings are essential steps toward reliable and valid quantification of tissue perfusion using ICG NIR fluorescence imaging.

Identifying Patients at High Risk for Post-EVAR Aneurysm Sac Growth.

PURPOSE: Post-EVAR (endovascular aneurysm repair) aneurysm sac growth can be seen as therapy failure as it is a risk factor for post-EVAR aneurysm rupture. This study sought to identify preoperative patient predictors for developing post-EVAR aneurysm sac growth. MATERIAL AND METHODS: A systematic review was conducted to select potential predictive preoperative factors for post-EVAR sac growth (including a total of 34.886 patients), which were evaluated by a retrospective single-center analysis of patients undergoing EVAR between 2009 and 2019 (N=247) with pre-EVAR computed tomography scans and at least 1 year follow-up. The primary study outcome was post-EVAR abdominal aortic aneurysm (AAA) sac enlargement (≥5 mm diameter increase). Multivariate Cox regression and Kaplan-Meier survival curves were constructed. RESULTS: Potential correlative factors for post-EVAR sac growth included in the cohort analysis were age, sex, anticoagulants, antiplatelets, renal insufficiency, anemia, low thrombocyte count, pulmonary comorbidities, aneurysm diameter, neck diameter, neck angle, neck length, configuration of intraluminal thrombus, common iliac artery diameter, the number of patent lumbar arteries, and a patent inferior mesenteric artery. Multivariate analysis showed that infrarenal neck angulation (hazard ratio, 1.014; confidence interval (CI), 1.001-1.026; p=0.034) and the number of patent lumbar arteries (hazard ratio, 1.340; CI, 1.131-1.588; p<0.001) were associated with post-EVAR growth. Difference in estimated freedom from post-EVAR sac growth for patients with ≥4 patent lumbar arteries versus <4 patent lumbar arteries became clear after 2 years: 88.5% versus 100%, respectively (p<0.001). Of note, 31% of the patients (n=51) with ≥4 patent lumbar arteries (n=167) developed post-EVAR sac growth. In our cohort, the median maximum AAA diameter was 57 mm (interquartile range [IQR] = 54-62) and the median postoperative follow-up time was 54 months (IQR = 34-79). In all, 23% (n=57) of the patients suffered from post-EVAR growth. The median time for post-EVAR growth was 37 months (IQR = 24-63). In 46 of the 57 post-EVAR growth cases (81%), an endoleak was observed; 2.4% (n=6) of the patients suffered from post-EVAR rupture. The total mortality in the cohort was 24% (n=60); 4% (n=10) was AAA related. CONCLUSIONS: This study showed that having 4 or more patent lumbar arteries is an important predictive factor for postoperative sac growth in patients undergoing EVAR. CLINICAL IMPACT: This study strongly suggests that having 4 or more patent lumbar arteries should be included in preoperative counseling for EVAR, in conjunction to the instructions for use (IFU).

Excess Mortality for Abdominal Aortic Aneurysms and the Potential of Strict Implementation of Cardiovascular Risk Management: A Multifaceted Study Integrating Meta-Analysis, National Registry, and PHAST and TEDY Trial Data.

OBJECTIVE: Previous studies imply a profound residual mortality risk following successful abdominal aorta aneurysm (AAA) repair. This excess mortality is generally attributed to increased cardiovascular risk. The aim of this study was (1) to quantify the excess residual mortality for patients with AAA, (2) to evaluate the cross sectional level of cardiovascular risk management, and (3) to estimate the potential of optimised cardiovascular risk management to reduce the excess mortality in these patients. METHODS: Excess mortality was estimated through a systematic review and meta-analysis, and through data from the Swedish National Health Registry. Cardiovascular risk profiles were individually assessed during eligibility screening of patients with AAA for two multicentre pharmaceutical AAA stabilisation trials. The potential of full implementation of cardiovascular risk management was estimated through the validated Second Manifestations of ARTerial disease (SMART) risk scores algorithm. RESULTS: The meta-analysis showed a similarly impaired survival for patients who received early repair (small AAA) or regular repair (≥ 55 mm), and a further impaired survival for patients under surveillance for a small AAA. Excess mortality was further quantified using Swedish population data. The data revealed a more than quadrupled and doubled five year mortality rate for women and men who had their AAA repaired, respectively. Evaluation of the level of risk management of 358 patients under surveillance in 16 Dutch hospitals showed that the majority of patients with AAA did not meet therapeutic targets set for risk management in high risk populations, and indicated a more pronounced prevention gap in women. Application of the SMART risk score algorithm predicted that optimal implementation of risk management guidelines would reduce the 10 year risk of major adverse cardiovascular events from 43% to 14%. CONCLUSION: Independent of the rupture risk, AAA is associated with a worryingly compromised life expectancy with a particularly poor prognosis for women. Optimal implementation of cardiovascular risk prevention guidelines is predicted to profoundly reduce cardiovascular risk.

Nutcracker Syndrome: Challenges in Diagnosis and Surgical Treatment.

BACKGROUND: Nutcracker syndrome (NCS) is an uncommon syndrome that presents with signs and symptoms caused by compression of the left renal vein (LRV), whereas 'nutcracker phenomenon' is solely used to refer to the anatomical configuration without clinical symptoms. Treatment for NCS may include nonoperative management, open surgical intervention, and in some instances endovascular stenting. We present a single-center retrospective case series of patients who presented with NCS managed with open surgical interventions. METHODS: A single-center, retrospective review of patients managed from 2010-2021. We diagnosed NCS via a thorough clinical examination and additional cross-sectional imaging studies including magnetic resonance venography and/or computed tomography venography. For further confirmation of the diagnosis, duplex ultrasound was frequently combined with contrast venography. RESULTS: Thirty eight patients were included in our study from 2010-2021. Twenty one (55.3%) patients presented with symptoms including flank pain, abdominal pain, hematuria, and fatigue. The remaining 17 (44.7%) patients had nutcracker phenomenon. Within the group of patients diagnosed with NCS, 11 patients underwent LRV transposition. Symptoms related to NCS improved in 10 patients. Hematuria in 1 patient did not improve. CONCLUSIONS: Transposition of the LRV is an effective treatment for NCS. Nonoperative management is an option for those patients experiencing less severe or nonspecific clinical symptoms.

Learning Curve Analysis of Complex Endovascular Aortic Repair.

BACKGROUND: When introducing new techniques, attention must be paid to learning curve. Besides quantitative outcomes, qualitative factors of influence should be taken into consideration. This retrospective cohort study describes the quantitative learning curve of complex endovascular aortic repair (EVAR) in a nonhigh-volume academic center and provides qualitative factors that were perceived as contributors to this learning curve. With these factors, we aim to aid in future implementation of new techniques. METHODS: All patients undergoing complex EVAR in the Leiden University Medical Center (LUMC) between July 2013 and April 2021 were included (n = 90). Quantitative outcomes were as follows: operating time, blood loss, volume of contrast, hospital stay, major adverse events (MAE), 30-day mortality, and complexity. Patients were divided into 3 temporal groups (n = 30) for dichotomous outcomes. Regression plots were used for continuous outcomes. In 2017, the treatment team was interviewed by an external researcher. These interviews were reanalyzed for factors that contributed to successful implementation. RESULTS: Length of hospital stay (P = 0.008) and operating time (P = 0.010) decreased significantly over time. Fewer cardiac complications occurred in the third group (3: 0% vs. 2: 17% vs. 1: 17%, P = 0.042). There was a trend of increasing complexity (P = 0.076) and number of fenestrations (P = 0.060). No significant changes occurred in MAE and 30-day mortality. Qualitative factors that, according to the interviewees, positively influenced the learning curve were as follows: communication, mutual trust, a shared sense of responsibility and collective goals, clear authoritative structures, mutual learning, and team capabilities. CONCLUSIONS: In addition to factors previously identified in the literature, new learning curve factors were found (mutual learning and shared goals in the operating room (OR)) that should be taken into account when implementing new techniques.

Evaluation of the Angiosome Concept Using Near-Infrared Fluorescence Imaging with Indocyanine Green.

BACKGROUND: The angiosome concept is defined as the anatomical territory of a source artery within all tissue layers. When applying this theory in vascular surgery, direct revascularization (DR) is preferred to achieve increased blood flow toward the targeted angiosome of the foot in patients with lower extremity arterial disease (LEAD). This study evaluates the applicability of the angiosome concept using quantified near-infrared (NIR) fluorescence imaging with indocyanine green (ICG). METHODS: This study included patients undergoing an endovascular- or surgical revascularization of the leg between January 2019 and December 2021. Preinterventional and postinterventional ICG NIR fluorescence imaging was performed. Three angiosomes on the dorsum of the foot were determined: the posterior tibial artery (hallux), the anterior tibial artery (dorsum of the foot) and the combined angiosome (second to fifth digit). The angiosomes were classified from the electronic patient records and the degree of collateralization was classified based on preprocedural computed tomography angiography and/or X-ray angiography. Fluorescence intensity was quantified in all angiosomes. A subgroup analysis based on endovascular or surgical revascularized angiosomes, and within critical limb threatening ischemia (CLTI) patients was performed. RESULTS: ICG NIR fluorescence measurements were obtained in 52 patients (54 limbs) including a total of 157 angiosomes (121 DR and 36 indirect revascularizations [IR]). A significant improvement of all perfusion parameters in both the directly and indirectly revascularized angiosomes was found (P-values between <0.001-0.007). Within the indirectly revascularized angiosomes, 90.6% of the scored collaterals were classified as significant. When comparing the percentual change in perfusion parameters between the directly and indirectly revascularized angiosomes, no significant difference was seen in all perfusion parameters (P-values between 0.253 and 0.881). Similar results were shown in the CLTI patients subgroup analysis, displaying a significant improvement of perfusion parameters in both the direct and indirect angiosome groups (P-values between <0.001 and 0.007), and no significant difference when comparing the percentual parameter improvement between both angiosome groups (P-values between 0.134 and 0.359). Furthermore, no significant differences were observed when comparing percentual changes of perfusion parameters in directly and indirectly revascularized angiosomes for both endovascular and surgical interventions (P-values between 0.053 and 0.899). CONCLUSIONS: This study proves that both DR and IR of an angiosome leads to an improvement of perfusion. This suggests that interventional strategies should not only focus on creating in-line flow to the supplying angiosome. One can argue that the angiosome concept is not applicable in patients with LEAD.

Room for resilience: a qualitative study about accountability mechanisms in the relation between work-as-done (WAD) and work-as-imagined (WAI) in hospitals.

BACKGROUND: Central to Safety-II is promoting resilience of healthcare practices. In the "Room for Resilience" research project we focus on the role of horizontal and vertical accountability in healthcare teams and aim to discover how the relation between the two impacts team reflections and discussions. In this article, we report on an explorative study at the start of the project which aimed to assess the structures and dynamics of horizontal and vertical accountability. METHODS: A qualitative study in six teams in three hospitals in the Netherlands. For the project, each team selected a specific clinical process to work on (e.g. pain assessment). We interviewed healthcare professionals, managers, and quality advisors about these processes, how they are discussed in practice and how teams need to account for them. Additionally, we observed the processes and how teams discuss them in practice. In total, we conducted 35 interviews and 67.5 h of observation. Transcripts and field notes were analyzed using thematic analysis. RESULTS: Professionals at times varied in what they considered the right approach in the clinical process, with differing views on the importance of certain actions. When processes were discussed, this mostly was done during clinical work, and it often concerned reflections about the care for a specific patient instead of reflecting on the team's general approach of the clinical process. Organized reflections on the processes were sparse. How processes were conducted in practice deviated from guidelines, mainly due to staff shortages, a perceived lack of value of a guideline, equipment issues, and collaboration issues. For most processes, accountability to hierarchical layers consisted of quality indicator scores. Professionals were tasked with registering indicator data but did not find this meaningful for their work. CONCLUSIONS: The observed different perspectives within teams on what good quality care is show the importance of having team reflections about these processes. How vertical accountability was organized at times impacted the conditions for teams to discuss resilient performance. Following these findings, we recommend that reflection on resilient practice and the role of accountability processes is organized on all levels in (and outside) the organization.

High on-treatment platelet reactivity in peripheral arterial disease: A systematic review.

OBJECTIVES: To highlight current evidence pertaining to the measurement methods and prevalence of high on-treatment platelet reactivity (HTPR) in patients with PAD, as well as to evaluate the relationship between HTPR and recurrent adverse cardiovascular and limb events in PAD patients. METHODS: A systematic review of English-language literature on HTPR in patients with PAD. An electronic literature search of PubMed and Medline was performed in May 2021. RESULTS: A total of 29 studies with a total number of 11,201 patients with PAD were identified. HTPR during clopidogrel treatment ranges from 9.8 to 77%, and during aspirin treatment ranges from 4.1 to 50% of PAD patients. HTPR was associated with adverse clinical outcomes. The need for limb revascularisation was higher in patients with HTPR during clopidogrel use. Similarly, HTPR during aspirin use in the PAD population was predictive of adverse cardiovascular events (HR 3.73; 95% CI, 1.43-9.81; p = .007). A wide range of techniques were applied to measure platelet resistance, without consensus on cut-off values. Furthermore, differing patient populations, a variety of antiplatelet regimens, and differing clinical endpoints highlight the high degree of heterogeneity in the studies included in this review. CONCLUSION: No consensus on technique or cut-off values for HTPR testing has been reached. Patients with HTPR are potentially at a greater risk of adverse limb-related and cardiovascular events than patients sensitive to antiplatelet therapy illustrating the need for clinical implementation of HTPR testing. Future research must aim for consistent methodology. Adaptation of antiplatelet therapy based on HTPR results requires further exploration.

Exploring the Effects of Human Bone Marrow-Derived Mononuclear Cells on Angiogenesis In Vitro.

Cell therapies involving the administration of bone marrow-derived mononuclear cells (BM-MNCs) for patients with chronic limb-threatening ischemia (CLTI) have shown promise; however, their overall effectiveness lacks evidence, and the exact mechanism of action remains unclear. In this study, we examined the angiogenic effects of well-controlled human bone marrow cell isolates on endothelial cells. The responses of endothelial cell proliferation, migration, tube formation, and aortic ring sprouting were analyzed in vitro, considering both the direct and paracrine effects of BM cell isolates. Furthermore, we conducted these investigations under both normoxic and hypoxic conditions to simulate the ischemic environment. Interestingly, no significant effect on the angiogenic response of human umbilical vein endothelial cells (HUVECs) following treatment with BM-MNCs was observed. This study fails to provide significant evidence for angiogenic effects from human bone marrow cell isolates on human endothelial cells. These in vitro experiments suggest that the potential benefits of BM-MNC therapy for CLTI patients may not involve endothelial cell angiogenesis.

Computed tomography follow-up after elective proximal aortic surgery: Less is more?

STUDY OBJECTIVE: The added value of computed tomography (CT) follow-up after elective proximal aortic surgery is unclear. We evaluated the benefit of CT follow-up by assessing the incidence of aorta-related complications and reinterventions detected during routine CT follow-up. METHODS: Data on 314 patients undergoing first time elective proximal aortic surgery between 2000 and 2015 were collected. The primary study end points were aorta-related complications and reinterventions, detected during routine CT follow-up. Secondary study endpoints included all aorta-related complications and reinterventions, irrespective of the mode of detection and survival. RESULTS: Median CT follow-up time was 6.8 (IQR 4.1-9.8) years, during which a total of 1303 routine follow-up CT-scans (median 4, IQR 3-5) were performed. During CT follow-up, aorta-related complications were detected in 18 (5.7%) patients, of which 6 (1.6%) underwent reintervention. In total, 28 aorta-related complications were observed in 23 (7.3%) patients, of which 9 led to reintervention. In order to detect 1 aorta-related complication leading to reintervention, 218 routine follow-up CT-scans were required. The unadjusted and EuroSCORE II adjusted hazard ratios of not undergoing CT follow-up on mortality were 1.260 (95% CI 0.705-2.251) and 0.830 (95% CI 0.430-1.605), respectively. CONCLUSIONS: Following first time elective proximal aortic surgery, aorta-related complications are uncommon, are not always detected during CT follow-up and, if detected, often do not result in reintervention. Therefore, a more conservative CT follow-up protocol could be considered in selected patients to reduce lifetime radiation burden and health care costs.

Treatment Outcome Trends for Non-Ruptured Abdominal Aortic Aneurysms: A Nationwide Prospective Cohort Study.

OBJECTIVE: The Dutch Surgical Aneurysm Audit (DSAA) initiative was established in 2013 to monitor and improve nationwide outcomes of aortic aneurysm surgery. The objective of this study was to examine whether outcomes of surgery for intact abdominal aortic aneurysms (iAAA) have improved over time. METHODS: Patients who underwent primary repair of an iAAA by standard endovascular (EVAR) or open surgical repair (OSR) between 2014 and 2019 were selected from the DSAA for inclusion. The primary outcome was peri-operative mortality trend per year, stratified by OSR and EVAR. Secondary outcomes were trends per year in major complications, textbook outcome (TbO), and characteristics of treated patients. The trends per year were evaluated and reported in odds ratios per year. RESULTS: In this study, 11 624 patients (74.8%) underwent EVAR and 3 908 patients (25.2%) underwent OSR. For EVAR, after adjustment for confounding factors, there was no improvement in peri-operative mortality (aOR [adjusted odds ratio] 1.06, 95% CI 0.94 - 1.20), while major complications decreased (2014: 10.1%, 2019: 7.0%; aOR 0.91, 95% CI 0.88 - 0.95) and the TbO rate increased (2014: 68.1%, 2019: 80.9%; aOR 1.13, 95% CI 1.10 - 1.16). For OSR, the peri-operative mortality decreased (2014: 6.1%, 2019: 4.6%; aOR 0.89, 95% CI 0.82 - 0.98), as well as major complications (2014: 28.6%, 2019: 23.3%; aOR 0.95, 95% CI 0.91 - 0.99). Furthermore, the proportion of TbO increased (2014: 49.1%, 2019: 58.3%; aOR 1.05, 95% CI 1.01 - 1.10). In both the EVAR and OSR group, the proportion of patients with cardiac comorbidity increased. CONCLUSION: Since the establishment of this nationwide quality improvement initiative (DSAA), all outcomes of iAAA repair following EVAR and OSR have improved, except for peri-operative mortality following EVAR which remained unchanged.

A New Doppler-Derived Parameter to Quantify Internal Carotid Artery Stenosis: Maximal Systolic Acceleration.

OBJECTIVE: Doppler ultrasonography (DUS) is used as initial measurement to diagnose and classify carotid artery stenosis. Local distorting factors such as vascular calcification can influence the ability to obtain DUS measurements. The DUS derived maximal systolic acceleration (ACCmax) provides a different way to determine the degree of stenosis. While conventional DUS parameters are measured at the stenosis itself, ACCmax is measured distal to the internal carotid artery (ICA) stenosis. The value of ACCmax in ICA stenosis was investigated in this study. MATERIAL AND METHODS: All carotid artery DUS studies of a tertiary academic center were reviewed from October 2007 until December 2017. Every ICA was included once. The ACCmax was compared to conventional DUS parameters: ICA peak systolic velocity (PSV), and PSV ratio (ICA PSV/ CCA PSV). ROC-curve analysis was used to evaluate accuracy of ACCmax, ICA PSV and PSV ratio as compared to CT-angiography (CTA) derived stenosis measurement as reference test. RESULTS: The study population consisted of 947 carotid arteries and was divided into 3 groups: <50% (710/947), 50-69% (109/947), and ≥70% (128/947). Between these groups ACCmax was significantly different. Strong correlations between ACCmax and ICA PSV (R2 0.88) and PSV ratio (R2 0.87) were found. In ROC subanalysis, the ACCmax had a sensitivity of 90% and a specificity of 89% to diagnose a ≥70% ICA stenosis, and a sensitivity of 82% and a specificity of 88% to diagnose a ≥50% ICA stenosis. For diagnosing a ≥50% ICA stenosis the area under the curve (AUC) of ACCmax (0.88) was significantly lower than the AUC of PSV ratio (0.94) and ICA PSV (0.94). To diagnose a ≥70% ICA stenosis there were no significant differences in AUC between ACCmax (0.89), PSV ratio (0.93) and ICA PSV (0.94). CONCLUSIONS: ACCmax is an interesting additional DUS measurement in determining the degree of ICA stenosis. ACCmax is measured distal to the stenosis and is not hampered by local distorting factors at the site of the stenosis. ACCmax can accurately diagnose an ICA stenosis, but was somewhat inferior compared to ICA PSV and PSV ratio to diagnose a ≥50% ICA stenosis.

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

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

Near-infrared fluorescence imaging with indocyanine green for quantification of changes in tissue perfusion following revascularization.

OBJECTIVES: Current diagnostic modalities for patients with peripheral artery disease (PAD) mainly focus on the macrovascular level. For assessment of tissue perfusion, near-infrared (NIR) fluorescence imaging using indocyanine green (ICG) seems promising. In this prospective cohort study, ICG NIR fluorescence imaging was performed pre- and post-revascularization to assess changes in foot perfusion. METHODS: ICG NIR fluorescence imaging was performed in 36 patients with PAD pre- and post-intervention. After intravenous bolus injection of 0.1 mg/kg ICG, the camera registered the NIR fluorescence intensity over time on the dorsum of the feet for 15 min using the Quest Spectrum Platform®. Time-intensity curves were plotted for three regions of interest (ROI): (1) the dorsum of the foot, (2) the forefoot, and (3) the hallux. Time-intensity curves were normalized for maximum fluorescence intensity. Extracted parameters were the maximum slope, area under the curve (AUC) for the ingress, and the AUC for the egress. The non-treated contralateral leg was used as a control group. RESULTS: Successful revascularization was performed in 32 patients. There was a significant increase for the maximum slope and AUC egress in all three ROIs. The most significant difference was seen for the maximum slope in ROI 3 (3.7%/s to 6.6%/s, p < 0.001). In the control group, no significant differences were seen for the maximum slope and AUC egress in all ROIs. CONCLUSIONS: This study shows the potential of ICG NIR fluorescence imaging in assessing the effect of revascularization procedures on foot perfusion. Future studies should focus on the use of this technique in predicting favorable outcome of revascularization procedures.