Editor's Choice - The Impact of Endovascular Aneurysm Repair on Long Term Renal Function Based on Hard Renal Outcomes.

INTRODUCTION: Over the short term endovascular aneurysm repair (EVAR) is associated with superior outcomes compared with open repair; however, the progression of renal function after EVAR remains unknown because of the use of inconsistent reporting measures. The aim was to define long term renal decline following elective EVAR using estimated glomerular filtration rate (eGFR). METHODS: The prospectively maintained in house database was used to identify consecutive patients having elective EVAR who had been followed up for more than five years. Overall, 275 patients (23 females, 8%; mean age, 75 years) who were not previously on renal replacement therapy (RRT) were included (January 2000 to July 2010). Pre-operative, post-operative, and most recent eGFR values were evaluated using the chronic kidney disease epidemiology collaboration equation. The primary outcome was change in eGFR at latest follow up. RESULTS: Patients were followed up over a median of 9 years (range 5-17 years). Their mean eGFR dropped from a pre-operative value of 67 mL/min/1.73 m2 (standard deviation [SD]: 9.4) to 52 mL/min/1.73 m2 (SD 7.7), which amounts to a yearly loss of 1.7 units; six patients (2%) required RRT (dialysis) during late follow up. Patients requiring RRT and those with an eGFR loss exceeding 20% at latest follow up compared with baseline were more likely to die during late follow up (odds ratio 2.4 and 3.3 respectively, p < .001). CONCLUSION: This analysis, with some of the longest available follow up to date, suggests that patients undergoing EVAR may experience a significant long term decrease in renal function. This needs to be taken into account when offering EVAR in younger patients; renal follow up and preservation should be optimised in this patient group.

Haematological risk factors predicting clinical success in transarterial embolisation for acute gastrointestinal bleeding.

OBJECTIVES: Evaluate clinical outcomes in transarterial embolisation (TAE) for acute gastrointestinal bleeding (GIB) and determine risk factors for 30-day reintervention for rebleeding and mortality. METHODS: TAE cases were retrospectively reviewed between March 2010 and September 2020 at our tertiary centre. Technical success (angiographic haemostasis following embolisation) was measured. Uni- and multivariate logistic regression analysis were performed to identify risk factors for clinical success (absence of 30-day reintervention or mortality) following embolisation for active GIB or empirical embolisation for suspected bleeding. RESULTS: TAE was conducted in 139 patients (92 (66.2%) male; median age:73, range: 20-95 years) for acute upper GIB (n = 88) and lower GIB (n = 51). TAE was technically successful in 85/90 (94.4%) and clinically successful in 99/139 (71.2%); with 12 (8.6%) reintervention cases for rebleeding (median interval 2 days) and 31 (22.3%) cases of mortality (median interval 6 days). Reintervention for rebleeding was associated with haemoglobin drop > 40 g l-1 from baseline based on univariate analysis (p = 0.047). 30-day mortality was associated with pre-intervention platelet count < 150×109 l-1 (p < 0.001, OR 7.35, 95% CI 3.05-17.71) and INR > 1.4 (p < 0.001, OR 4.75, 95% CI 2.03-11.09) on multivariate logistic regression analysis. No associations were found for patient age, gender, antiplatelet/anticoagulation prior to TAE, or when comparing upper and lower GIB with 30-day mortality. CONCLUSION: TAE had excellent technical success for GIB with relatively high (1-in-5) 30-day mortality. INR > 1.4 and platelet count < 150×109 l-1 were individually associated with TAE 30-day mortality, and pre-TAE > 40 g l-1 haemoglobin decline with rebleeding requiring reintervention. ADVANCES IN KNOWLEDGE: Recognition and timely reversal of haematological risk factors may improve TAE periprocedural clinical outcomes.

Feasibility of arterial spin labeling in evaluating high- and low-flow peripheral vascular malformations: a case series.

We present a case series highlighting a novel use of arterial spin labeling (ASL), a MRI perfusion technique, to evaluate both high- and low-flow peripheral vascular malformations (PVMs) across a range of anatomical locations. While the role of ASL in assessing intracranial vascular malformations is more established, there is limited evidence for PVMs. Our results provide preliminary evidence for the feasibility of ASL in imaging PVMs and its potential ability to distinguish between high- and low-flow PVMs. In addition, we demonstrate its ability to identify focal high blood flow, which may indicate the nidus in arteriovenous malformations. Together, these findings have important implications for patient management. We also outline the potential benefits and limitations of ASL in the imaging of PVMs, and provide justification for further validation of its diagnostic performance.

A comparison of arterial spin labelling with catheter angiography in evaluating arteriovenous malformations: a systematic review.

OBJECTIVES: To compare the performance of arterial spin labelling (ASL) in evaluating arteriovenous malformations (AVMs) against the current gold standard of catheter angiography. METHODS: We systematically reviewed the published literature using EMBASE and Medline. We included studies that compared ASL to catheter angiography in the assessment of AVMs in three outcome domains: detection, angioarchitectural and haemodynamic features. RESULTS: From 314 unique citations, 19 studies representing 289 patients with intracranial AVMs met our inclusion criteria. We did not pool data due to marked heterogeneity in study outcome measures. Seven studies showed high diagnostic performance of ASL in identifying arterial feeders, with sensitivity ranging from 84.6 to 100% and specificity ranging from 93.3 to 100%. Six studies showed strong ability in detecting arteriovenous shunting, with sensitivity ranging from 91.7 to 100% and specificity ranging from 90 to 100%. Seven studies demonstrated that ASL could identify nidal location and size as well as catheter angiography, while five studies showed relatively poorer performance in delineating venous drainage. Two studies showed 100% sensitivity of ASL in the identification of residual or obliterated AVMs following stereotactic radiosurgery. CONCLUSIONS: Despite limitations in the current evidence base and technical challenges, this review suggests that ASL has a promising role in the work-up and post-treatment follow-up of AVMs. Larger scale prospective studies assessing the diagnostic performance of ASL are warranted. ADVANCES IN KNOWLEDGE: ASL demonstrates overall validity in the evaluation of intracranial AVMs.

Novel use of arterial spin labelling in the imaging of peripheral vascular malformations.

We present a novel use of arterial spin labelling (ASL), a MRI perfusion technique, to assess a high-flow, peripheral vascular malformation (PVM), specifically a large arteriovenous malformation in the left forearm of a 20-year-old female. While there has been experience with ASL in the assessment of intracranial vascular malformations, there has been no known use of ASL in the evaluation of PVMs. We also discuss the potential benefits and limitations of ASL in the imaging of PVMs. The promising results from this case warrant further research on ASL in the investigation of PVMs.

Factors associated with pseudoaneurysm development and necessity for reintervention: a single centre study.

OBJECTIVE: Evaluate the factors associated with pseudoaneurysm development and morphology. Measure ultrasound-guided thrombin injection (UGTI) and surgical treatment outcomes for pseudoaneurysms, and the necessity for post-primary intervention (reintervention). METHODS: Retrospective analysis of ultrasound scans and CT angiography of peripheral pseudoaneurysm interventions from February 2011 to April 2017. 99 patients (61.6% female) were identified; median age 72 years (range 12-89). Multivariate analysis of patient demographics, including pre-intervention anticoagulant and antiplatelet medication was performed. RESULTS: Primary intervention for peripheral pseudoaneurysms (62.6% common femoral artery) included 93 UGTI and 6 surgical repairs; with 12 reinterventions (9 UGTI and 3 surgical). Pseudoaneurysm incidence for vascular interventional radiology (VIR) was 0.48% (31/6451) and cardiology was 0.24% (60/25,229). Rates for primary success, immediate complications, 30-day mortality and reintervention were measured respectively for UGTI (98.9%, 3.0%, 2.0%, and 11.8%) and surgical repair (100%, 0.0%, 22.2% and 16.7%). Reintervention risk factors included pre-intervention thrombocytopaenia (<150 × 109/L) ( p = 0.025) and pseudoaneurysms following vascular surgery (p = 0.033). Other positive associations for reintervention (non-significant) included use of a sheath size > 6 Fr ( p = 0.108) or arterial closure device ( p = 0.111) during the pseudoaneurysm causative procedure. The pre-intervention warfarin subgroup developed a larger mean pseudoaneurysm sac size (4.21 cm, range 0.9-7.6), compared to no treatment (p = 0.003), aspirin (p = 0.005) and clopidogrel (p = 0.026) subgroups. UGTI dosage for thrombosis had a positive correlation with incremental sac size increase (p < 0.001). CONCLUSION: The main reintervention risk factor was pre-intervention thrombocytopaenia, with additional positive associations including pseudoaneurysms caused by surgery, increased sheath size and arterial closure devices. Warfarinized patients developed larger sac-sized pseudoaneurysms compared with other pre-intervention regimens, with positive correlation of higher UGTI dosage required for thrombosis. ADVANCES IN KNOWLEDGE: Patients with pre-intervention thrombocytopaenia and pseudoaneurysms attributed to vascular surgery are subgroups that may benefit from post-intervention imaging surveillance due to significant reintervention risk.