Vascular Laboratory Research Articles

BEST PRACTICE FOR OPTIMIZATION AND RADIATION SAFETY IN THE CARDIOVASCULAR CATHETERIZATION ROOM (CATHLAB) OF SENTRA MEDIKA CIBINONG HOSPITAL

Scattered radiation generated during fluoroscopy increases the potential for patients and staff to receive radiation doses, so it is necessary to take optimization steps for radiation safety to minimize the risk of exposure to scattered X-ray radiation. This study aims to implement radiation protection in cardiac and vascular catheterization laboratories and summarize best practices for implementing efforts to minimize radiation exposure. The method used was qualitative and quantitative from 2023 to 2024; with this qualitative approach, the supervision activities in TLD badges for radiation workers, the level of diagnostic guidance for patients, and the use of radiation protection equipment were observed. For the quantitative approach, measuring the dose rate was carried out, and optimizing the positioning of the distance between the patient's table and the radiation source was carried out by direct measurement. Based on research data, the observation results obtained that the apron is still by the minimum thickness, which is 0.35-0.5 mm Pb for intervention, the results of exposure tests around the cathlab room are around 0.08-0.12 μSv/hour still below the dose constraint value, Mapping the rate of exposure in the work area during the intervention procedure obtained an optimal safe distance of around 60-70 cm from the X-ray tube. The setup of the effective distance position for intervention patients is at a distance of 80 cm from the X-ray tube to the patient table, which can reduce the absorbed dose to the patient by around 30%, the use of low dose mode (7.5 fps) with pulsed fluoroscopy during the intervention obtained the absorbed dose received by the patient reduced by 70-72% for PCI procedures and 25-29% for the type of CAG procedure. It is hoped that the protocol that uses this best practice can minimize the risk of exposure to scattered radiation and optimize medical exposure. Keywords: cathlab, best practices radiation protection, dose rate, radiation exposure, patient radiation dose.

Predictors of Successful Antibiotic Treatment of Osteomyelitis in Diabetic Forefoot Infection.

Osteomyelitis (OM) associated with diabetic foot ulceration (DFU) is a growing public health challenge worldwide. Since 2012 the number of patients presenting with DFU per year to our centre has doubled. This study aims to evaluate outcomes from outpatient antibiotic therapy (OPAT) in the management of OM in DFU patients. A retrospective analysis was performed of medical notes, radiology, and vascular laboratory reports for all DFU patients with OM treated from April 2016 to April 2020. Variables analyzed included age, gender, site of OM, WIfI Score (Wound Ischaemia and foot Infection Score), probe-to-bone test (PTB), imaging (X-ray/magnetic resonance imaging (MRI), co-morbidities (peripheral arterial disease (PAD), chronic kidney disease (CKD), hypertension (HTN), smoking, ischemic heart disease (IHD), and dyslipidaemia. Outcomes evaluated were healing, recurrent DFU, and freedom from amputation at 12months. 185 patients were admitted with 264 infected digits (Male 223; Female 41). The mean age was 66years. Only 168 (63.6%) were fully healed at 12months. Of the 96 patients who failed to heal, 43 underwent a repeat course of prolonged antibiotics without improvement. Factors associated with treatment failure were PAD, poorly controlled HbA1c and Deep or Extensive Ulcer or Gangrene. Extended outpatient antibiotic therapy (with an inpatient multidisciplinary approach) is an effective treatment for digital OM in DFU with a success rate of 63%. In recurrence, repeating prolonged antibiotics is unlikely to achieve healing. PAD, poorly controlled HbA1c and Deep or Extensive Ulcer or Gangrene are predictors of treatment failure.

Aspiring to Professionalism in the Vascular Laboratory

Aspiring to Professionalism in the Vascular Laboratory

Evaluating thermal comfort in a vascular interventional radiology laboratory: Utilizing an onsite measurement approach

A vascular interventional radiology (VIR) laboratory is a specialized medical environment designed for diagnostic and therapeutic procedures focused on blood vessels. In this facility, healthcare practitioners employ diverse imaging technologies such as fluoroscopy and angiography to visualize blood vessels and conduct minimally invasive interventions. This research examines the thermal comfort within a VIR laboratory through the field measurements. Assessing thermal comfort in a VIR laboratory supports Sustainable Development Goals (SDGs) by enhancing the welfare and working conditions in the healthcare settings (SDG 3 and SDG 9). This effort also aligns with SDG 11 by advocating for sustainable urban environments through the optimization of indoor environmental conditions. The gathered data brings to light notable disparities in air temperature, relative humidity, and air velocity, underscoring the absence of homogeneity in the laboratory setting. It's evident that 67% of the spaces within the VIR laboratory will induce a "cool" sensation among medical staff members in standby mode, with the remaining 33% causing a "slightly cool" sensation. Both the Predicted Percentage of Dissatisfied (PPD) and Predicted Mean Vote (PMV) indices for thermal comfort deviate from the established ASHRAE 55 standard, emphasizing the considerable hurdles in achieving the desired thermal conditions. By integrating findings from this study into policy frameworks, stakeholders can prioritize investments in infrastructure and technology aimed at enhancing thermal comfort standards in healthcare facilities. This proactive approach not only fosters a conducive environment for medical procedures but also advances progress towards achieving key SDGs.

The Incidence and Characteristics of Pelvic-Origin Varicosities in Patients with Complex Varices Evaluated by Ultrasonography.

The purpose of this study was to evaluate the incidence of gonadal vein refluxes associated with lower-extremity varicose veins with Doppler ultrasonography (DUS). A total of 6279 patients with venous disease-related symptoms of the lower extremity were evaluated with DUS in the vascular lab. Gonadal vein reflux using abdominal ultrasound was further evaluated in patients with unusual varices, defined as varices in the inguinal, inner or upper thigh and the vulvar area without refluxes in the saphenofemoral junction (SPJ). Those patients who showed gonadal vein reflux were diagnosed as having pelvic-origin varicosity. Unusual varices were found in a total of 237 patients (3.8%), and of these patients, pelvic-origin varicosity was discovered with transabdominal ultrasound in 156 (65.8%). A total of 66.7% (n = 38/57) of unusual varix patients with pelvic pain had gonadal vein reflux. The measurement of gonadal vein diameter was larger in ultrasonography than CT scans (8.835 vs. 8.81, p < 0.001). Two patients with severe symptoms but no obstructive venous diseases were treated with gonadal vein embolization. The incidence of pelvic-origin varicosities was 2.5% (n = 156/6279). However, more than half of the patients with unusual varices had gonadal vein reflux and 24.4% of these patients also presented with pelvic pain. The evaluation of pelvic-origin varicosities should be performed in patients who present with unusual forms of varices of the lower extremity.

Intermittent Tibial Artery Compressibility in the Noninvasive Vascular Laboratory: Implications for Diagnosis and Follow-Up

Objective: There is limited evidence available regarding intermittent tibial artery compressibility in the published literature. This investigation looks to determine the existence of intermittent tibial artery compressibility, in the noninvasive vascular laboratory. Materials and Methods: Consecutive patients underwent noninvasive arterial physiologic testing. An ankle-brachial index (ABI) ≥1.40 was defined as noncompressible and classified into 4 subgroups: (1) noncompressible single occurrence (NC-S), (2) noncompressible multiple occurrence (NC-M), (3) compressible to noncompressible (C-NC), and (4) intermittently compressible (I-C) ABI. Normal patients were compared to these noncompressible subgroups. Selective risk factors were compared in the C-NC and I-C ABI patient groups. Results: Of the 13 881 patients that were evaluated, 89% had compressible tibial arteries and 11% were noncompressible. Intermittent tibial artery compressibility was present in 11.3% of the patients, with noncompressible arteries. There were 718 patients from the NC-M, C-NC, and I-C subgroupings that had 3014 follow-up exams, over mean duration of 38 ± 27.7 months. The C-NC and I-C subgroup patients averaged 3.3 and 3.6 calcification risk factors, respectively. Conclusion: A subset of patients with intermittent tibial artery compressibility was confirmed in the noninvasive vascular laboratory. Additional research is needed to substantiate these findings and investigate whether intermittent compressibility may be marker for increased cardiovascular risk.

Exploring the Relationship of Cognitive and Motivational Factors to Sonography Student Performance

Objectives: The purpose of this mixed-methods study was to explore the cognitive and motivational challenges sonography students encounter by examining the relationships between sonography students’ levels of self-regulation and self-efficacy and their performance in a 16-week introductory vascular sonography skills laboratory course. Materials and Methods: Measures for the study were designed to yield qualitative and quantitative data related to student goals, strategies, and course performance and were generated by both students and faculty. Qualitative data from the study included student self-reports of self-regulatory strategies and instructor evaluations of student performance, while quantitative data were provided by instructor and student ratings of performance, student self-efficacy ratings, and student reports on their use of deliberate practice. Results: The data showed that many students learning how to perform sonographic examinations encountered motivational challenges that appeared to be tied both to their self-efficacy and their ability to effectively use self-regulatory activities. Conclusion: The findings of this study suggest possibilities for improving sonography’s curricular models and teaching strategies toward the goal of making sonography instruction more efficient and effective.

Indirect Duplex Ultrasound Diagnosis of Innominate Artery Occlusive Disease

Herein, we present a case study of a patient with suspected transient ischemic attacks who was referred to the vascular laboratory for an assessment of the extracranial cerebrovascular arteries. Duplex ultrasound revealed momentary flow reversal in the right common carotid artery and internal carotid artery. Reverse flow in the right vertebral artery and a dampened Doppler waveform in the right subclavian artery were suggestive of a subclavian steal syndrome. These findings were consistent with innominate artery (IA) stenosis or occlusion. This case study is confirmatory evidence that indirect sonographic techniques can reliably identify IA occlusive disease.

Analysis of retinal and choroidal microvascular changes using optical coherence tomography and optical coherence tomography angiography in patients with acute leukemia.

Although leukemic retinopathy accounts for 80% of ocular complications in acute leukemia, its pathogenesis remains unclear. To evaluate changes in retinal and choroicapillaris and structural parameters in patients with acute leukemia, we analyzed the correlation between vascular perfusion metrics and laboratory parameters and assessed the changes after hematopoietic stem cell transplantation (HSCT). Herein, 104 eyes of 52 patients aged 18 and above with acute leukemia were enrolled. 80 eyes of 40 healthy patients were recruited as control participants. All participants underwent optical coherence tomography (OCT) and OCT angiography (OCTA) at baseline. Patients with acute leukemia had a significantly thicker ganglion cell-inner plexiform layer (GCIPL) and lower circularity index than the control participants. Post-HSCT perfusion metrics did not differ significantly, but parafoveal thickness decreased significantly. During the active phase of acute leukemia, lower platelet levels were associated with significant GCIPL thickening and increased foveal avascular zone and perimeter. D-dimer levels positively correlated with GCIPL thickness. Patients with acute leukemia had subclinical retinal microvascular deficits on OCTA and GCIPL thickening on OCT, possibly associated with bone marrow function. GCIPL thickness may indicate acute ischemia in such patients. Further studies must elucidate their clinical and prognostic significance.

Calf rEF: Impact of Calf Muscle Pump Dysfunction With Reduced Ejection Fraction on All-Cause Mortality

ObjectiveTo evaluate mortality outcomes by varying degrees of reduced calf muscle pump (CMP) ejection fraction (EF). Patients and MethodsConsecutive adult patients who underwent venous air plethysmography testing at the Mayo Clinic Gonda Vascular Laboratory (January 1, 2012, through December 31, 2022) were divided into groups based on CMP EF for the assessment of all-cause mortality. Other venous physiology included measures of valvular incompetence and clinical venous disease (CEAP [clinical presentation, etiology, anatomy, and pathophysiology] score). Mortality rates were calculated using the Kaplan-Meier method. ResultsDuring the study, 5913 patients met the inclusion criteria. During 2.84-year median follow-up, there were 431 deaths. Mortality rates increased with decreasing CMP EF. Compared with EF of 50% or higher, the hazard ratios (95% CIs) for mortality were as follows: EF of 40% to 49%, 1.4 (1.0 to 2.0); EF of 30% to 39%, 1.6 (1.2 to 2.4); EF of 20% to 29%, 1.7 (1.2 to 2.4); EF of 10% to 19%, 2.4 (1.7 to 3.3) (log-rank P≤.001). Although measures of venous valvular incompetence did not independently predict outcomes, venous disease severity assessed by CEAP score was predictive. After adjusting for several clinical covariates, both CMP EF and clinical venous disease severity assessed by CEAP score remained independent predictors of mortality. ConclusionMortality rates are higher in patients with reduced CMP EF and seem to increase with each 10% decrement in CMP EF. The mortality mechanism does not seem to be impacted by venous valvular incompetence and may represent variables intrinsic to muscular physiology.

Reduced calf muscle pump function is not explained by handgrip strength measurements

ObjectiveReduced calf muscle pump function (CPF) is an independent risk factor for venous thromboembolism and mortality. We aimed to evaluate the relationship between handgrip strength (HGS) and CPF. MethodsPatients referred to the Gonda Vascular Laboratory for noninvasive venous studies were identified and consented. Patients underwent standard venous air plethysmography protocol. CPF (ejection fraction) was measured in each lower extremity of ambulatory patients by comparing refill volume after ankle flexes and passive refill volumes. The cutoff for reduced CPF (rCPF) was defined as an ejection fraction of <45%. Maximum HGS bilaterally was obtained (three trials per hand) using a dynamometer. HGS and CPF were compared (right hand to calf, left hand to calf) and the correlation between the measures was evaluated. Results115 patients (mean age, 59.2 ± 17.4 years; 67 females, mean body mass index, 30.83 ± 6.46) were consented and assessed for HGS and CPF. rCPF was observed in 53 right legs (46%) and 67 left legs (58%). CPF was reduced bilaterally in 45 (39%) and unilaterally in 30 (26%) patients. HGS was reduced bilaterally in 74 (64.3%), unilaterally in 23 (20%), and normal in 18 (15.7%) patients. Comparing each hand/calf pair, no significant correlations were seen between HGS and CPF. The Spearman's rank correlation coefficients test yielded values of 0.16 for the right side and 0.10 for the left side. ConclusionsThere is no significant correlation between HGS and CPF, demonstrating that HGS measurements are not an acceptable surrogate for rCPF, indicating different pathophysiological mechanisms for each process.

The mid-term results of the Carotid Asymptomatic Stenosis (CARAS) observational study

IntroductionCarotid endarterectomy (CEA) in patients with asymptomatic carotid stenosis (ACAS) remains a subject of debate. Current recommendations are based on randomized trials conducted over 20 years ago and improvements in medical therapies may have reduced the risk of cerebral ischemic events (CIE). This study presents a mid-term analysis of results from an ongoing prospective observational study of ACAS patients to assess their CIE risk in a real-world setting. MethodsThis is a prospective observational cohort study of patients with ACAS >60 % (NASCET criteria) identified in a single duplex ultrasonography (DUS) vascular laboratory (trial registered: NCT04825080). Patients were not considered for CEA due to their short life expectancy (<3 year) or absence of signs of plaque vulnerability (ulceration, ipoechogenic core). Patient enrollment started in January 2019 and ended in March 2020 with a targeted sample size of 300 patients.A 5-year follow-up was scheduled. Clinical characteristics, risk factors, and medical therapies were documented, and, when necessary, the best medical therapy (BMT), involving antiplatelet agents, blood pressure control, and statins, was recommended during clinical visits. The primary endpoint was to asses CIEs (including strokes, transient ischemic attacks, amaurosis-fugax) ipsilateral to ACAS along with plaque progression rate and patients survival. Follow-up involved annual clinical visit and carotid DUS examination, complemented by telephone interviews at six-month intervals. ResultsThe study included 307 patients, with an average age of 80 ± 7 years, of whom 55 % were male. Contralateral stenosis exceeding 60 % was present in 61 (20 %) patients. Seventy-seven percent of patients were on BMT. At a mean follow-up of 41±9 months, 7 ispilateral strokes and 9 TIAs occurred, resulting in 14 CIEs (2 patients experienced both TIA and stroke). According to Kaplan–Meier analysis, the 4-year CIE rate was 6±2 %, with an annual CIE rate of 1.5 %. Fifty-eight (19 %) patients had a stenosis progression which was associated with a higher 4-year estimated CIE rate compared to patients with stable plaque (10.3 % vs 3.2 %, P=.01). Similarly, a contralateral carotid stenosis >60 % was associated with a higher 4-year estimated CIE rate: 11.7 % vs 2.9 %, P=.002. These factors were independently associated with high risk for CIE at the multivariate COX analysis: Hazard Ratio (HR): 3.2; 95 % Confidence Interval: 1.1-9.2 and HR: 3.6; 95 % CI: 1.2-10.5. ConclusionThe mid-term results of this prospective study suggest that the incidence of CIE in ACAS patients should not be underestimated, with plaque progression and contralateral stenosis serving as primary predictors of CIEs.

Vascular laboratory workshop increases medical student understanding of vascular diagnostic studies and promotes interest in vascular surgery specialty

ObjectiveThe rising prevalence of vascular pathology and its associated costs in the United States burdens the health care system. This study tackles the impending shortage of vascular surgeons by examining ways to increase medical students’ interest and competence in vascular surgery. It assesses the impact of a two-session vascular laboratory (VL) workshop on medical students’ understanding of vascular pathologies, their ability to interpret VL studies, and their interest in pursuing a career in vascular surgery. MethodsApproval was obtained for this survey-based study from the Institutional Review Board at the University of Maryland School of Medicine. The study involved two cohorts: the VL group (n = 30), consisting of medical students that participated in the VL workshop during their vascular surgery rotation, and the control group (n = 25) consisting of medical students on a General Surgery (GS) rotation not exposed to the VL workshop. The VL group attended two workshops that included lectures, hands-on training, and clinical shadowing. After the workshops, they completed surveys assessing their understanding of vascular pathologies and VL assessments. The GS group, recruited via email, also completed surveys evaluating their exposure to vascular surgery and understanding of VL studies. Both groups were assessed using subjective and objective multiple-choice questions. ResultsFollowing the VL workshop, the vast majority of the VL group reported greater confidence with understanding, ordering, and performing vascular lab testing. Conversely, 72% (n = 18/25) of the GS cohort self-reported little to no confidence in their understanding of the VL or ability to determine the appropriate VL study based on indication. The VL group demonstrated significantly better performance on objective questions related to vascular pathologies compared with the GS group. Both groups expressed a desire for inclusion of VL education within their preclinical years (49/55; 89.1%). Finally, two-thirds (20/30; 66.7%) of the VL group reported a significant increase in their interest in vascular surgery following the workshop. ConclusionsA two-session VL workshop significantly enhances medical student confidence in utilizing diagnostic tools for assessing vascular pathology and fosters interest in vascular surgery. Implementing such workshops during preclinical education may provide earlier exposure, more research opportunities, and potentially increase medical student interest in pursuing vascular surgery as a career. Additionally, it may improve the competence of graduating medical students in diagnosing and treating vascular patients across all specialties. These findings emphasize the importance of innovative educational approaches to address the growing demand for vascular care in the United States.

Quality assurance in the vascular laboratory

Quality assurance in the vascular laboratory

Popliteal artery aneurysm ultrasound criteria for reporting characteristics.

Duplex ultrasound (DUS) is the modality of choice for surveillance of popliteal artery aneurysms (PAAs). However, noninvasive vascular laboratories have no standard guidelines for reporting results. This study assessed reports of PAA DUS for inclusion of information pertinent to operative decision-making and timing of surveillance. This study was a retrospective review of a multi-institutional repository that was queried for all patients with a PAA from 2008 to 2022 and confirmed via manual chart review. DUS reports were abstracted and images were individually annotated for features of interest including dimensions, flow abnormalities, and percent thrombus burden. A total of 166 PAAs in 130 patients had at least one DUS available for viewing. Postoperative surveillance of PAAs was performed at several intervals: the first at 30 months (IQR 3.7-113, n = 44), the second at 64 months (IQR 20-172, n = 31), and the third at 152 months (IQR 46-217, n = 16) after the operation. The largest diameter of operative PAAs (median 27.5 mm, IQR 21.8-38.0) was significantly greater than nonoperative PAAs (median 20.9 mm, IQR 16.7-27.3); p < 0.01. Fewer than 33 (21%) reports commented on patency of distal runoff. We calculated an average percent thrombus of 60% (IQR 19-81) in nonoperative PAAs, which is significantly smaller than 75% (IQR 58-89) in operative PAAs; p < 0.01. In this multi-institutional retrospective study, PAAs are often not followed at intervals recommended by the Society for Vascular Surgery guidelines and do not include all measurements necessary for clinical decision-making in the multi-institutional repository studied. There should be standardization of PAA DUS protocols performed by all noninvasive vascular laboratories to ensure completeness of PAA DUS images and inclusion of characteristics pertinent to clinical decision-making in radiology reports.

Discordance of patient-reported outcome measures with objectively assessed walking decline in peripheral artery disease

ObjectiveAmong people with peripheral artery disease (PAD), perceived change in walking difficulty over time, compared with people without PAD, is unclear. Among people reporting no change in walking difficulty over time, differences in objectively measured change in walking performance between people with and without PAD are unknown. MethodsA total of 1289 participants were included. Eight hundred seventy-four participants with PAD (aged 71.1 ± 9.1 years) were identified from noninvasive vascular laboratories and 415 without PAD (aged 69.9 ± 7.6 years) were identified from people with normal vascular laboratory testing or general medical practices in Chicago. The Walking Impairment Questionnaire and 6-minute walk were completed at baseline and 1-year follow-up. The Walking Impairment Questionnaire assessed perceived difficulty walking due to symptoms in the calves or buttocks on a Likert scale (range, 0-4). Symptom change was determined by comparing difficulty reported at 1-year follow-up to difficulty reported at baseline. ResultsAt 1-year follow-up, 31.9% of participants with and 20.6% of participants without PAD reported walking difficulty that was improved (P < .01), whereas 41.2% vs 55%, respectively, reported walking difficulty that was unchanged (P < .01). Among all reporting no change in walking difficulty, participants with PAD declined in 6-minute walk, whereas participants without PAD improved (−10 vs +15 meters; mean difference, −25; 95% confidence interval, −38 to −13; P < .01). ConclusionsMost people with PAD reported improvement or no change in walking difficulty from calf or buttock symptoms at one-year follow-up. Among all participants who perceived stable walking ability, those with PAD had significant greater declines in objectively measured walking performance, compared with people without PAD.

An International Expert-Based CONsensus on Indications and Techniques for aoRtic balloOn occLusion in the Management of Ruptured Abdominal Aortic Aneurysms (CONTROL-RAAA)

Objective: To report on the recommendations of an expert-based consensus on the indications, timing, and techniques of aortic balloon occlusion (ABO) in the management of ruptured abdominal aortic aneurysms (rAAA). Methods: Eleven facilitators created appropriate statements regarding the study issues that were voted on using a 4-point Likert scale with open-comment fields, by a selected panel of international experts (vascular surgeons and interventional radiologists) using a 3-round modified Delphi consensus procedure (study period: January-April 2023). Based on the experts’ responses, only the statements reaching grade A (full agreement ≥75%) or B (overall agreement ≥80% and full disagreement &lt;5%) were included in the final study report. The consistency of each round’s answers was also graded using Cohen’s kappa, the intraclass correlation coefficient, and, in case of double resubmission, Fleiss kappa. Results: Sixty-three experts were included in the final analysis and voted on 25 statements related to indication and timing (n=6), and techniques (n=19) of ABO in the setting of rAAA. Femoral sheath or ABO should be preferably placed in the operating room, via a percutaneous transfemoral access, on a stiff wire (grade B, consistency I), ABO placement should be suprarenal and last less than 30 minutes (grade B, consistency II), postoperative peripheral vascular status (grade A, consistency II) and laboratory testing every 6 to 12 hours (grade B, consistency) should be assessed to detect complications. Formal training for ABO should be implemented (grade B, consistency I). Most of the statements in this international expert-based Delphi consensus study might guide current choices for indications, timing, and techniques of ABO in the management of rAAA. Clinical practice guidelines should incorporate dedicated statements that can guide clinicians in decision-making. Conclusions: At arrival and during both open or endovascular procedures for rAAA, selective use of intra-aortic balloon occlusion is recommended, and it should be performed preferably by the treating physician in aortic pathology. Clinical Impact This is the first consensus study of international vascular experts aimed at defining the indications, timing, and techniques of optimal use of ABO in the clinical setting of rAAA. Aortic occlusion by endovascular means (or ABO) is a quick procedure in properly trained hands that may play an important role as a temporizing measure until the definitive aortic repair is achieved, whether by endovascular or open means. Since data on its use in hemodynamically unstable patients are limited in the literature, owing to practical challenges in the performance of well-conducted prospective studies, understanding real-world use by experts is of importance in addressing critical issues and identifying main gaps in knowledge.

Safety of bilateral arm pressure measurements in the diagnostic workup of dialysis-associated steal syndrome.

Although bilateral brachial pressure measurement is routinely included in the diagnostic work-up of upper extremity ischemia, it is generally avoided in the presence of hemodialysis access due to fears of inducing access thrombosis. This study evaluated the safety of bilateral brachial pressure measurement in patients with clinical suspicion of dialysis-associated steal syndrome (DASS). Patients undergoing non-invasive testing for steal syndrome between September 2015 and December 2021 were included in this study. The diagnostic workup was performed by certified vascular sonographers in an outpatient vascular lab and consisted of bilateral brachial pressures, photoplethysmography, and duplex ultrasonography of the access. Interarm differential (IAD) was defined as systolic blood pressure (SBP) in the contralateral arm minus SBP in the access arm. The primary endpoint was immediate access thrombosis. The study sample consisted of 331 subjects with a mean age of 61 ± 13 and a median access age of 9 months (3-31 months) with radiocephalic fistulas present in 29%. Many patients (68%) presented with paresthesia and 4% presented with tissue loss. The mean brachial systolic pressure was 152 ± 37 mmHg on the ipsilateral arm versus 143 ± 34 mmHg on the contralateral (p-value <0.001), with an inter-arm differential (IAD) of -8.4 ± 19 mmHg. A total of 16 subjects (5%) presented a differential ⩾20 mmHg. A positive thrill was noted in all the accesses immediately following blood pressure measurement and no occurrence of access thrombosis was noted at 30 days. Proximal arterial revascularization interventions were performed in 11 cases (3%). Subjects who presented an IAD ⩾20 mmHg had lower ipsilateral digital-brachial index (0.39 ± 0.18 vs 0.68 ± 0.26; p = 0.037), a higher tendency of being referred for angiograms (37.5% vs 10.5%, p = 0.006), and more proximal arterial revascularization procedures (25.0% vs 2.2%, p = 0.001). Bilateral arm pressure measurement in the context of dialysis access-associated steal syndrome (DASS) appears safe and useful for identifying subjects whose symptoms are due to proximal arterial inflow disease. We therefore recommend this test be considered in the diagnostic algorithms of DASS.

Duplex ultrasound and cross-sectional imaging in carotid artery occlusion diagnosis

ObjectiveInvestigations into imaging modalities in the diagnosis of extracranial carotid artery occlusion (CAO) have raised questions about the inter-modality comparability of duplex ultrasound (DUS) and cross-sectional imaging (CSI). This study examines the relationship between DUS and CSI diagnoses of extracranial CAO. MethodsThis single-institution retrospective analysis studied patients with CAO diagnosed by DUS from 2010 to 2021. Patients were identified in our office-based accredited vascular laboratory database. Imaging and clinical data was obtained via our institutional electronic medical record. Primary outcome was discrepancy between DUS and CSI modalities. Secondary outcomes included incidence of stroke and intervention subsequent to CAO diagnosis. ResultsOf our 140-patient cohort, 95 patients (67.9%) had DUS follow-up (mean, 42.7 ± 31.3 months). At index duplex, 68.0% of individuals (n = 51) were asymptomatic. Seventy-five patients (53.6%) had CSI of the carotids after DUS CAO diagnosis; 18 (24%) underwent magnetic resonance imaging and 57 (76%) underwent computed tomography. Indications for CSI included follow-up of DUS findings of carotid stenosis/occlusion (44%), stroke/transient ischemic attack (16%), other symptoms (12%), preoperative evaluation (2.7%), unrelated pathology follow-up (9.3%), and outside institution imaging with unavailable indications (16%). When comparing patients with CSI and those without, there were no differences with regard to symptoms at diagnosis, prior neck interventions, or hypertension. There was a significant difference between cross-sectionally imaged and non-imaged patients in anti-hypertensive medications (72% vs 53.8%; P = .04). Despite initial DUS diagnoses of carotid occlusion, 10 patients (13.3%) ultimately had CSI indicating patent carotids. Four of these 10 patients had stenoses of ∼99% (with 1 string sign), four of 70% to 99%, one of 50% to 69%, and one of less than 50% on CSI. The majority of patients (70%) had CSI within 1 month of the index ultrasound. There were no significant relationships between imaging discrepancies and body mass index, heart failure, upper body edema, carotid artery calcification, and neck hardware. Eight individuals (10.7%) underwent ipsilateral revascularization; 62.5% (n = 5) were carotid endarterectomy procedures, and the remaining three procedures were a transcervical carotid revascularization, subclavian to internal carotid artery bypass, and transfemoral carotid artery stenting. Eight patients (10.7%) underwent contralateral revascularization, with the same distribution of procedures as those ipsilateral to occlusions. Two of the 10 patients with discrepancies underwent carotid endarterectomy, and one underwent carotid stenting. ConclusionsIn our experience, duplex diagnosis of CAO is associated with a greater than 10% discordance when compared with CSI. These patients may benefit from closer surveillance as well as confirmatory computed tomography or magnetic resonance angiography. Further work is needed to determine the optimal diagnostic modality for CAO.

Rapid Carotid Screening by Duplex: A Prospective Single Centre Assessment.

A novel carotid quick scan (CQS) protocol was developed to rapidly screen for carotid atherosclerosis greater than 50% stenosis in a vascular outpatient setting. This study assessed accuracy and time saved. The CQS was developed by consensus agreement between vascular surgeons and accredited clinical vascular scientists through a modified Delphi technique. The protocol comprised a rapid B-mode then colour flow transverse sweep of the common and internal carotid arteries, with internal carotid artery velocity assessment. One hundred outpatients attending with peripheral artery disease or abdominal aortic aneurysm were recruited. CQS sensitivity, specificity and accuracy was assessed against a conventional full carotid duplex study, performed to UK and ESVS guidelines. Twenty four percent of patients (n = 100) had >50% carotid NASCET stenosis. CQS achieved an excellent accuracy of 96.5% in detecting >50% stenosis when compared to full duplex; Cohen's ƙ = .88, (95%CI .79-.97; P < .001), sensitivity 91.4%, specificity 97.6%, positive predictive value (PPV) 88.9% and negative predictive value (NPV) 98.2%. Median (IQR) time to complete the CQS was 13 sec (±12) per side, compared to 151 sec (±78) per side for the full carotid duplex. In the presence of >50% carotid disease, median CQS time was 25 sec (±31) per side compared to 214 (±104) by full scan. CQS as a carotid screening tool is rapid, accurate and acceptable to the population and workforce. It would be simple to roll out in all vascular laboratories to reduce the time and cost burden of excluding significant carotid disease in any group.