Clinical Applications of Conebeam CTP Imaging in Cerebral Disease: A Systematic Review.

BACKGROUND: Perfusion imaging with multidetector CT is integral to the evaluation of patients presenting with ischemic stroke due to large-vessel occlusion. Using conebeam CT perfusion in a direct-to-angio approach could reduce workflow times and improve functional outcome. PURPOSE: Our aim was to provide an overview of conebeam CT techniques for quantifying cerebral perfusion, their clinical applications, and validation. DATA SOURCES: A systematic search was performed for articles published between January 2000 and October 2022 in which a conebeam CT imaging technique for quantifying cerebral perfusion in human subjects was compared against a reference technique. STUDY SELECTION: Eleven articles were retrieved describing 2 techniques: dual-phase (n = 6) and multiphase (n = 5) conebeam CTP. DATA ANALYSIS: Descriptions of the conebeam CT techniques and the correlations between them and the reference techniques were retrieved. DATA SYNTHESIS: Appraisal of the quality and risk of bias of the included studies revealed little concern about bias and applicability. Good correlations were reported for dual-phase conebeam CTP; however, the comprehensiveness of its parameter is unclear. Multiphase conebeam CTP demonstrated the potential for clinical implementation due to its ability to produce conventional stroke protocols. However, it did not consistently correlate with the reference techniques. LIMITATIONS: The heterogeneity within the available literature made it impossible to apply meta-analysis to the data. CONCLUSIONS: The reviewed techniques show promise for clinical use. Beyond evaluating their diagnostic accuracy, future studies should address the practical challenges associated with implementing these techniques and the potential benefits for different ischemic diseases.

The accuracy of gap and step-off measurements in acetabular fracture treatment.

The assessment of gaps and steps in acetabular fractures is challenging. Data from various imaging techniques to enable accurate quantification of acetabular fracture displacement are limited. The aim of this study was to assess the accuracy of pelvic radiographs, intraoperative fluoroscopy, and computed tomography (CT) in detecting gaps and step-offs in acetabular fractures. Sixty patients, surgically treated for acetabular fractures, were included. Five observers (5400 measurements) measured the gaps and step-offs on radiographs and CT scans. Intraoperative fluoroscopy images were reassessed for the presence of gaps and/or step-offs. Preoperatively, 25% of the gaps and 40% of the step-offs were undetected on radiographs compared to CT. Postoperatively, 52% of the gaps and 80% of the step-offs were missed on radiographs compared to CT. Radiograph analysis led to a significantly smaller gap and step-off compared to the CT measurements, an underestimation by a factor of two. Approximately 70% of the residual gaps and step-offs was not detected using intraoperative fluoroscopy. Gaps and step-offs that exceed the critical cut-off indicating worse prognosis often remained undetected on radiographs compared to CT scans. Less-experienced observers tend to overestimate gaps and step-offs compared to the more-experienced observers. In acetabular fracture treatment, gaps and step-offs were often undetected and underestimated on radiographs and intraoperative fluoroscopy in comparison with CT scans. This means that CT is superior to radiographs in detecting acetabular fracture displacement, which is clinically relevant for patient counselling regarding treatment decisions and prognosis.

A Metamodeling Approach for Instant Severity Assessment and Uncertainty Quantification of Iliac Artery Stenoses.

Two-dimensional (2D) or three-dimensional (3D) models of blood flow in stenosed arteries can be used to patient-specifically predict outcome metrics, thereby supporting the physicians in decision making processes. However, these models are time consuming which limits the feasibility of output uncertainty quantification (UQ). Accurate surrogates (metamodels) might be the solution. In this study, we aim to demonstrate the feasibility of a generalized polynomial chaos expansion-based metamodel to predict a clinically relevant output metric and to quantify the output uncertainty. As an example, a metamodel was constructed from a recently developed 2D model that was shown to be able to estimate translesional pressure drops in iliac artery stenoses (-0.9 ± 12.7 mmHg, R2 = 0.81). The metamodel was constructed from a virtual database using the adaptive generalized polynomial chaos expansion (agPCE) method. The constructed metamodel was then applied to 25 stenosed iliac arteries to predict the patient-specific pressure drop and to perform UQ. Comparing predicted pressure drops of the metamodel and in vivo measured pressure drops, the mean bias (-0.2 ± 13.7 mmHg) and the coefficient of determination (R2 = 0.80) were as good as of the original 2D computational fluid dynamics (CFD) model. UQ results of the 2D and metamodel were comparable. Estimation of the uncertainty interval using the original 2D model took 14 days, whereas the result of the metamodel was instantly available. In conclusion, it is feasible to quantify the uncertainty of the output metric and perform sensitivity analysis (SA) instantly using a metamodel. Future studies should investigate the possibility to construct a metamodel of more complex problems.

Quantitative 3D measurements of tibial plateau fractures.

Fracture gap and step-off measurements on 2DCT-slices probably underestimate the complex multi-directional features of tibial plateau fractures. Our aim was to develop a quantitative 3D-CT (Q3DCT) fracture analysis of these injuries. CT-based 3D models were created for 10 patients with a tibial plateau fracture. Several 3D measures (gap area, articular surface involvement, 3D displacement) were developed and tested. Gaps and step-offs were measured in 2D and 3D. All measurements were repeated by six observers and the reproducibility was determined by intra-class correlation coefficients. Q3DCT measurements demonstrated a median gap of 5.3 mm, step-off of 5.2 mm, gap area of 235 mm2, articular surface involvement of 33% and 3D displacement of 6.1 mm. The inter-rater reliability was higher in the Q3DCT than in the 2DCT measurements for both the gap (0.96 vs. 0.81) and step-off (0.63 vs. 0.32). Q3DCT measurements showed excellent reliability (ICC of 0.94 for gap area, 1 for articular surface involvement and 0.99 for 3D displacement). Q3DCT fracture analysis of tibial plateau fractures is feasible and shows excellent reliability. 3D measurements could be used together with the current classification systems to quantify the true extent of these complex multi-directional fractures in a standardized way.

Introduction of a three-dimensional computed tomography measurement method for acetabular fractures.

INTRODUCTION: Acetabular fractures consist of complex fracture patterns whereby bone fragments are displaced in different directions. Two-dimensional computed tomography (2DCT) gap and step-off measurements tend to underestimate the multidirectional features of these fractures. The aim was to develop a three-dimensional computed tomography (3DCT) measurement method for acetabular fractures and validate whether this method will provide an observer independent fracture characterization. MATERIALS AND METHODS: Sixty patients, operated for an acetabular fracture between 2007 and 2018, were included. The displacement was measured on the pre- and postoperative CT scans. Pre- and postoperative CT-based 3D models were made for each patient. Multiple 3D measurements, namely the 3D step-off, gap and the total gap area were introduced to quantify the preoperative and postoperative displacement. The Wilcoxon signed rank analysis was used to compare the 2DCT and 3DCT measurements. RESULTS: The preoperative displacement was significantly underestimated by 2DCT measurements in comparison with 3DCT measurements (2D vs. 3D; step-off 8 vs. 16 mm with P < 0.001; gap 19 vs. 21 mm with P = 0.001). The same applies to the postoperative residual displacement (2D vs. 3D; step-off 0 vs. 6 mm; gap 3 vs. 8 mm; P < 0.001). The total gap area, defined as the surface area between all fracture lines in the 3D model, was measured for each patient, resulting in a median value of 722 mm2 preoperatively and 168 mm2 postoperatively, with excellent inter- and intra-rater reliability. CONCLUSION: 2DCT measurements tend to underestimate the initial and residual displacement in complex acetabular fractures. A 3DCT analysis of these injuries was developed to overcome this and should be used in addition to the Judet/Letournel and AO/OTA classification systems, in order to provide an observer independent quantifiable fracture description and accurate assessment of the fracture reduction.

A geometry-based model for non-invasive estimation of pressure gradients over iliac artery stenoses.

The aim of this study was to develop and verify a model that provides an accurate estimation of the trans-lesion hyperemic pressure gradient in iliac artery stenoses in seconds by only using patient-specific geometric properties obtained from 3-dimensional rotational angiography (3DRA). Twenty-one patients with symptomatic peripheral arterial disease (PAD), iliac artery stenoses and an ultrasound based peak systolic velocity ratio between 2.5 and 5.0 underwent 3DRA and intra-arterial pressure measurements under hyperemic conditions. For each lesion, geometric properties were extracted from the 3DRA images using quantitative vascular analysis software. Hyperemic blood flow was estimated based on stenosis geometry using an empirical relation. The geometrical properties and hyperemic flow were used to estimate the pressure gradient by means of the geometry-based model. The predicted pressure gradients were compared with in vivo measured intra-arterial pressure measurements performed under hyperemic conditions. The developed geometry-based model showed good agreement with the measured hyperemic pressure gradients resulting in a concordance correlation coefficient of 0.86. The mean bias ±â€¯2SD between the geometry-based model and in vivo measurements was comparable to results found by evaluating the actual computational fluid dynamics model (-1.0 ±â€¯14.7 mmHg vs -0.9 ±â€¯12.7 mmHg). The developed model estimates the trans-lesional pressure gradient in seconds without the need for an additional computational fluid dynamics software package. The results justify further study to assess the potential use of a geometry-based model approach to estimate pressure gradient on non-invasive CTA or MRA, thereby reducing the need for diagnostic angiography in patients suffering from PAD.

The Nellix device: review of indications and outcome.

INTRODUCTION: Despite improvements in endograft design, operator skills, and patient selection, late endovascular abdominal aortic aneurysm repair (EVAR) associated complications and need for reinterventions remains the Achilles heel. These complications erode the early benefit over open aneurysm repair during long-term follow-up. The recently introduced endovascular aneurysm sealing (EVAS) is an innovative technology with the intention to lower these EVAR related complications. Areas covered: In this review the EVAS technique, indications, and possible applications, will be discussed, as well as a critical appraisal of clinical outcomes. Expertcommentary: EVAS is a promising technique for treating abdominal aortic aneurysms, and early efficacy data are encouraging in very suitable straight forward anatomy. The Nellix device is still in development. Longterm results are awaited.

Time-dependent trends in cardiovascular adverse events during follow-up after carotid or iliofemoral endarterectomy.

BACKGROUND: Recent observations have suggested a decline in vulnerable carotid artery and iliofemoral atherosclerotic plaque characteristics over the past decade. The aim of this study was to determine whether, in the presence of clinically manifest carotid or peripheral artery disease, secondary adverse cardiovascular events decreased over this period. METHODS: Patients included in the Athero-Express biobank between 2003 and 2012 were analysed. During 3-year follow-up, composite cardiovascular endpoints were documented yearly, including: myocardial infarction, coronary interventions, stroke, peripheral interventions and cardiovascular death. The major cardiovascular endpoint consisted of myocardial infarction, stroke and cardiovascular death. RESULTS: Some 1684 patients who underwent carotid endarterectomy (CEA) and another 530 who had iliofemoral endarterectomy (IFE) were analysed. In total, 405 (25·2 per cent) and 236 (45·9 per cent) patients had a composite cardiovascular endpoint within 3 years after CEA and IFE respectively. Corrected for possible confounders, the percentage of patients with a secondary cardiovascular event after CEA did not change over time (hazard ratio (HR) 0·91, 95 per cent c.i. 0·65 to 1·28; P = 0·590, for 2011-2012 versus 2003-2004). In patients who had IFE, the incidence of secondary cardiovascular events significantly decreased only in the last 2 years (HR 0·62, 0·41 to 0·94; P = 0·024), owing to a decrease in peripheral (re)interventions in 2011-2012 (HR 0·59, 0·37 to 0·94; P = 0·028). No decrease in major cardiovascular events was observed in either group. CONCLUSION: In patients who had undergone either CEA or IFE there was no evidence of a decrease in all secondary cardiovascular events. There were no differences in major cardiovascular events.

Macroscopic and Histologic Analysis of Vessel Wall Reaction After Mechanochemical Endovenous Ablation Using the ClariVein OC Device in an Animal Model.

OBJECTIVE/BACKGROUND: Mechanochemical endovenous ablation (MOCA) has been developed as a tumescentless technique to ablate saphenous veins and to avoid heat induced complications and post-procedural pain. The mechanism of action of MOCA is poorly understood. The present experiments were conducted to determine the effect of MOCA on vein wall injury and sclerosis in an animal model. METHODS: A total of 36 lateral saphenous veins (LSVs) were treated in 18 goats according to the human protocol. Veins from nine goats were evaluated 45 min after the procedure, while in the remaining nine, the treated veins were evaluated 6 weeks later. All treated veins were divided equally over three treatment groups: (i) MOCA, (ii) mechanical ablation without the sclerosant, and (iii) liquid sclerotherapy alone. The histological effects of treatment on the vein wall were systematically evaluated. RESULTS: The average diameter of the LSV was 4.0 ± 0.5 mm. Technical success was achieved in all but one LSV (35/36; 97%), with a median procedure time of 14 min (range 9-22 min). In the acute group, histological examination showed that mechanical ablation (alone or MOCA) induced severe injury to the endothelium in 82% but no damage to other layers of the vein wall. Mechanical ablation led to vasoconstriction. After 6 weeks follow-up, four of six MOCA treated veins were occluded. The occluded segments consisted mainly of fibrotic lesions probably evolved from organised thrombus. No occlusions were observed after sclerotherapy or mechanical treatment alone. No major complications occurred during procedures or follow-up. CONCLUSION: MOCA is associated with an increased occlusion rate compared with its separated components of mechanical ablation or sclerotherapy. The occlusion consists of cellular fibrotic material likely to be evolved from organised thrombus with fibrotic alterations to the surrounding media and adventitia. This study underlines the hypothesis that the additive use of MOCA increases the effectiveness of sclerosants alone by inducing endothelial damage and probably vasoconstriction.

Venous Arterialisation for Salvage of Critically Ischaemic Limbs: A Systematic Review and Meta-Analysis.

BACKGROUND: Critical limb ischaemia (CLI) is the end stage of peripheral artery disease (PAD) and is associated with high amputation and mortality rates and poor quality of life. For CLI patients with no revascularisation options, venous arterialisation could be a last resort for limb salvage. OBJECTIVE: To review the literature on the clinical effectiveness of venous arterialisation for lower limb salvage in CLI patients with no revascularisation options. METHOD: Different databases were searched for papers published between January 1966 and January 2016. The criteria for eligible articles were studies describing outcomes of venous arterialisation, published in English, human studies, and with the full text available. Additionally, studies were excluded if they did not report limb salvage, wound healing or amputation as outcome measures. The primary outcome measure was post-operative limb salvage at 12 months. Secondary outcome measures were 30 day or in-hospital mortality, survival, patency, technical success, and wound healing. RESULTS: Fifteen articles met the inclusion criteria. The included studies described 768 patients. According to the MINORS score, methodological quality was moderate to poor. The estimated pooled limb salvage rate at one year was 75% (0.75, 95% CI 0.70-0.81). Thirty day or in-hospital mortality was reported in 12 studies and ranged from 0 to 10%. Overall survival was reported in 10 studies and ranged from 54% to 100% with a mean follow-up ranging from 5 to 60 months. Six studies reported on patency of the venous arterialisations performed, with a range of 59-71% at 12 months. CONCLUSION: In this systematic review on venous arterialisation in patients with non-reconstructable critical limb ischaemia, the pooled proportion of limb salvage at 12 months was 75%. Venous arterialisation could be a valuable treatment option in patients facing amputation of the affected limb; however, the current evidence is of low quality.

Monitoring of Foot Oxygenation with Near-infrared Spectroscopy in Patients with Critical Limb Ischemia Undergoing Percutaneous Transluminal Angioplasty: A Pilot Study.

OBJECTIVE: Near-infrared spectroscopy (NIRS) non-invasively determines tissue oxygen saturation (Sto2) in muscle tissue. Its application to monitor real time hemodynamic changes during percutaneous transluminal angioplasty (PTA) and Sto2 changes in feet 4 weeks after PTA was evaluated. METHODS: This study included 14 patients with critical limb ischemia (CLI, six patients Rutherford classification Stage IV, two patients Stage V, and six patients Stage VI). In patients with arterial ulcers, NIRS optodes were placed near the ulcer of the diseased foot (Optode 1), and at the same spot at the contralateral foot (Optode 2). In patients without arterial ulcers, Optode 1 was placed on the dorsum of the diseased foot, and Optode 2 was placed on the dorsum of the contralateral foot. Single Sto2 values, ankle brachial indices, and toe brachial indices were obtained at rest before the start of endovascular revascularization and 4 weeks after treatment. During the endovascular procedure, continuous Sto2 measurements were recorded throughout the intervention. Completion angiograms were used to evaluate the success of intervention. RESULTS: Patients underwent treatment of the superficial femoral artery (79%), popliteal artery (21%), and below the knee arteries (43%). In 13 of the 14 patients, completion angiograms showed successful treatment of target lesions. Ankle brachial indices and toe brachial indices significantly increased 4 weeks after treatment (both p < .01). Single Sto2 values of Optode 1 also significantly increased four weeks after treatment (p < .01). In contrast, single Sto2 values of Optode 2 did not (p = .73). During the endovascular procedure, continuous Sto2 measurements of Optode 1 and 2 did not increase (p = .80, and p = .61, respectively). CONCLUSIONS: NIRS monitoring of foot oxygenation in patients undergoing endovascular revascularization is safe and feasible. NIRS is a promising non-invasive technique to monitor hemodynamic changes in the feet of CLI patients after endovascular treatment using single Sto2 values.

Banding for type IA endoleak after endovascular abdominal aortic repair: An underexposed treatment option.

More challenging abdominal aortic aneurysms with unfavorable proximal aortic neck anatomy are treated with endovascular means. As a consequence, proximal inadequate sealing may result in type IA endoleak, which in turn can lead to abdominal aortic aneurysm progression or rupture. The presence of type IA endoleak is an indication for secondary interventions. External aortic banding can be a good option to solve a type IA endoleak, but is underreported in literature; we present two cases and review literature.

Aortic Curvature Instead of Angulation Allows Improved Estimation of the True Aorto-iliac Trajectory.

OBJECTIVE: Supra- and infrarenal aortic neck angulation have been associated with complications after endovascular aortic aneurysm repair. However, a uniform angulation measurement method is lacking and the concept of angulation suggests a triangular oversimplification of the aortic anatomy. (Semi-)automated calculation of curvature along the center luminal line describes the actual trajectory of the aorta. This study proposes a methodology for calculating aortic (neck) curvature and suggests an additional method based on available tools in current workstations: curvature by digital calipers (CDC). METHODS: Proprietary custom software was developed for automatic calculation of the severity and location of the largest supra- and infrarenal curvature over the center luminal line. Twenty-four patients with severe supra- or infrarenal angulations (≥45°) and 11 patients with small to moderate angulations (<45°) were included. Both CDC and angulation were measured by two independent observers on the pre- and postoperative computed tomographic angiography scans. The relationships between actual curvature and CDC and angulation were visualized and tested with Pearson's correlation coefficient. The CDC was also fully automatically calculated with proprietary custom software. The difference between manual and automatic determination of CDC was tested with a paired Student t test. A p-value was considered significant when two-tailed α < .05. RESULTS: The correlation between actual curvature and manual CDC is strong (.586-.962) and even stronger for automatic CDC (.865-.961). The correlation between actual curvature and angulation is much lower (.410-.737). Flow direction angulation values overestimate CDC measurements by 60%, with larger variance. No significant difference was found in automatically calculated CDC values and manually measured CDC values. CONCLUSION: Curvature calculation of the aortic neck improves determination of the true aortic trajectory. Automatic calculation of the actual curvature is preferable, but measurement or calculation of the curvature by digital calipers is a valid alternative if actual curvature is not at hand.

Changes in Aortoiliac Anatomy After Elective Treatment of Infrarenal Abdominal Aortic Aneurysms with a Sac Anchoring Endoprosthesis.

OBJECTIVE: Endovascular aortic sealing (EVAS) with the Nellix endosystem (Endologix, Irvine, CA, USA) is a new concept to treat infrarenal abdominal aortic aneurysms (AAAs). By sealing the aneurysm, potential endoleaks may be avoided. Early results of EVAS are good, but no data have been published regarding peri-procedural changes in aortoiliac anatomy. In this study, 27 consecutive patients who underwent elective EVAS repair of an AAA were reviewed. METHOD: Specific AAA (diameter, length from renal arteries to aortic bifurcation, supra- and infrarenal neck angulation, AAA volume, thrombus volume, and flow lumen volume), and iliac artery characteristics (length, angulation, location of most severe angulation with reference to the origin of the common iliac artery) were determined from pre- and post-procedural reconstructed computed tomography angiograms. RESULTS: No type I or II endoleaks were seen at 30 day follow up. Total AAA volume, suprarenal and infrarenal angulation, as well as aortic neck diameter did not change significantly post-EVAS. AAA flow lumen increased significantly (mean difference -4.4 mL, 95% CI 2.0 to -8.6 mL) and AAA thrombus volume decreased (mean difference 3.2 mL, 95% CI 2.0 to -1.1 mL). AAA length (125.7 mm vs. 123.1 mm), left common iliac artery length (57.6 mm vs. 55.3 mm), and right and left maximum iliac artery angulation (right 37.4° vs. 32.2°; left: 43.9° vs. 38.4°) were reduced significantly and the location of maximum angulation was further from the iliac artery origin post-EVAS, suggesting slight straightening of the aortoiliac anatomy. CONCLUSION: Most aortoiliac anatomic characteristics remained unchanged post-EVAS. Filling of the endobags to a pressure of 180 mmHg may lead to lost thrombus volume in some patients, probably because liquid is squeezed into lumbar or the inferior mesenteric artery. The absolute differences in pre- and post-EVAS aortoiliac lengths were small, so pre-operative sizing is accurate for determining stent length.

Common variants associated with blood lipid levels do not affect carotid plaque composition.

INTRODUCTION: Although plasma lipid levels are known to influence the risk of cardiovascular disease (CVD), little is known about their effect on atherosclerotic plaque composition. To date, large-scale genome-wide association studies have identified 157 common single-nucleotide polymorphisms (SNPs) that influence plasma lipid levels, providing a powerful tool to investigate the effect of plasma lipid levels on atherosclerotic plaque composition. METHODS: In this study, we included 1443 carotid endarterectomy patients from the Athero-Express Biobank Study with genotype data. Plasma concentrations of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC) and triglycerides (TG) were determined at the time of endarterectomy. Atherosclerotic plaques, obtained during surgery, were histologically examined. For all patients, we calculated weighted genetic burden scores (GBS) for all lipid traits on the basis of the available genotype data. Plasma lipid levels and GBS were tested for association with 7 histological features using linear and logistic regression models. RESULTS: All GBS were associated with their respective plasma lipid concentrations (pHDL-C = 2.4 × 10(-14), pLDL-C = 0.003, pTC = 2.1 × 10(-6), pTG = 3.4 × 10(-8)). Neither the measured plasma lipids, nor the GBS, were associated with histological features of atherosclerotic plaque composition. In addition, neither the plasma lipids nor the GBS were associated with clinical endpoints within 3 years of follow-up, with the notable exception of a negative association between HDL-C and composite cardiovascular endpoints. CONCLUSION: This study found no evidence that plasma lipid levels or their genetic determinants influence carotid plaque composition.

Technical and Clinical Success and Long-Term Durability of Endovascular Treatment for Atherosclerotic Aortic Arch Branch Origin Obstruction: Evaluation of 144 Procedures.

OBJECTIVES: Endovascular treatment of atherosclerotic obstruction of aortic arch branch origins (AABO) has largely replaced open surgery, but long-term outcome data are lacking. This study evaluated mid-term and long-term results of these procedures. DESIGN: Retrospective cohort study. MATERIALS AND METHODS: Patients underwent endovascular treatment for symptomatic atherosclerotic stenosis of AABO between 1995 and 2012. Technical success was defined as uncomplicated revascularization and residual stenosis ≤30%. The primary end point was freedom from restenosis ≥50% on Duplex ultrasonography or magnetic resonance angiography. Secondary end points were freedom from target lesion revascularization or recurrent symptoms. RESULTS: 144 lesions were treated in 114 patients (75 female; mean age 66.3 years), by percutaneous transluminal angioplasty (PTA) in 20 patients and PTA and stent in 117 patients (brachiocephalic artery [BCA] 9/54; left common carotid artery [LCCA] 0/7; left subclavian artery [LSA] 11/56). The lesion could not be passed in four patients, and in three patients the intervention was terminated before angioplasty. The 30-day technical success was 94.4%, without deaths or strokes. Mean follow-up was 52.0 months (range 2-163 months). Restenosis-free survival was 95.6%, 92.9%, 87.6%, and 83.2% at 12, 24, 48, and 60 months, respectively. Log-rank test showed no significant difference between PTA only and PTA with additional stent placement at any point (p = .375), nor between BCA (n = 51), LCCA (n = 6), or LSA (n = 57). During follow-up, 27 patients (23.7%) became symptomatic (15 BCA, 1 LCCA, and 11 LSA); 19 patients with a restenosis of the target lesion (mean 56.7 months). Symptom-free survival was 94.7%, 92.0%, 82.3%, and 77.9% at 12, 24, 48, and 60 months, respectively. CONCLUSION: Endovascular treatment of aortic arch branch origin obstruction is safe and efficacious in experienced hands and can be considered as the preferred treatment, with good mid-term durability. Recurrent symptomatic lesions can be treated safely by renewed endovascular means.

Catheter-directed thrombolysis for acute upper extremity ischemia.

AIM: Acute nontraumatic upper extremity ischemia has significant chronic disability when not treated adequately and timely. As surgical treatment can be challenging, this study evaluates catheter-directed thrombolysis as first-line treatment for acute upper extremity ischemia. METHODS: Between January 2006 and December 2010, 28 patients (22 women; mean age, 63±16 years) underwent catheter-directed thrombolysis for acute upper extremity ischemia, Rutherford class I or IIa. Proximal extent of the occlusion was in the subclavian (32%), axillary (7%), brachial (25%) and forearm arteries (36%). Median occlusion length was 18 cm (range, 12-43). Causes were embolus (14%), thrombus (39%), thoracic outlet syndrome (14%), paraneoplastic (4%), or unknown (29%). RESULTS: Technical success was 96%, radiologic success (>95% clot lysis) 61%, and clinical success 68%. Median duration of thrombolysis was 24 hours (range, 18-96). Of the 11 radiologically unsuccessful patients (39%), five were treated conservatively and six underwent surgical intervention. In-hospital amputation-rate was 7%. Four complications occurred: embolization to the lower extremity, a transient ischemic attack, a subcapsular splenic hematoma and a pseudoaneurysm. Cumulative amputation-free survival at six months was 93%, standard error (SE) 4.87 and at one year 88%, SE 6.50. CONCLUSION: These results show that catheter-directed thrombolysis is effective in over 60% of patients as first-line treatment of extensive acute upper extremity ischemia and can prevent surgical intervention in these patients.