Utility of Dual-Energy Computed Tomography in lesion characterization and treatment planning for peripheral Chronic Total Occlusions: A comprehensive analysis of crossing difficulty.

PURPOSE: To investigate whether Dual-Energy Computed Tomography (DECT) could be useful in the lesion characterization and endovascular treatment planning of symptomatic patients with peripheral arterial disease (PAD) due to Chronic Total Occlusions (CTO). MATERIALS AND METHODS: Between 2018 and 2022, 60 symptomatic patients (52 male, age 71 years) with peripheral arterial CTO underwent DECT angiography before percutaneous endovascular treatment. Patients were classified, according to guidewire crossing difficulty into four categories, which were subsequently correlated with DECT values, including Dual Energy Index (DEI) and Effective Z (Zeff). DECT values were also corelated with crossing time. The crossing difficulty was further correlated with the Trans-Atlantic Inter-Society Consensus Document (TASC II) classification. RESULTS: Technical success, defined as perceived antegrade true lumen or subintimal crossing, was achieved in 76.7 %. Among the cases, 20 were deemed easy, 14 moderate, 12 hard and 14 were failed attempts. Statistical analysis revealed a significant correlation between DEI, Zeff values, and the crossing difficulty categories (p < 0.001). Additionally, there was also a correlation between crossing time and DECT values. However, no significant correlation was recorded between difficulty categories and TASC II classification. CONCLUSION: Pre-procedural DECT angiography provides valuable information for patient selection and planning of the revascularization strategy. Moreover, it is helpful in the selection of the appropriate PTA materials, based on the lesion characteristics. Further research should be invested in this important field, to determine the optimal treatment approach in patients suffering from PAD due to CTOs.

Concomitant vascular and orthopedic trauma: 10 points to consider.

Although vascular injuries complicate only 1-2% of patients with orthopedic trauma, they may be encountered in a much higher rate of around 10 % in injuries around the knee and elbow joints following both fractures and dislocations. In case of vascular involvement, specific diagnostic and therapeutic challenges arise and there is a higher risk for significant morbidity (i.e. limb loss) or mortality. In the absence of randomized data, diagnostic and therapeutic algorithms are not always straightforward and clinical practice may be based on experience and local protocols rather than firm evidence. With this article we intend to review available literature regarding concomitant skeletal and vascular trauma in order to provide concise information and clear guidelines of when to operate with least investigations and when to go for a full spectrum of investigations in the absence of hard clinical signs. Additionally, other aspects concerning the manipulation of these patients are discussed, such as the indications of primary amputation, the potential role of endovascular techniques and the value of the Resuscitative Endovascular Balloon Occlusion of the Aorta. In summary, this scoping review summarizes current practices in the diagnostic and therapeutic management of patients with concomitant orthopedic and vascular injuries, discusses different treatment strategies and gives a practical perspective for implementation on every day practice.

Technical challenges during emergent endovascular aneurysm repair with the ALTO system.

INTRODUCTION: Ruptured abdominal aortic aneurysms (AAAs) pose an immediate threat for patient's life and endovascular repair (EVAR) is currently the preferred treatment modality in the presence of suitable anatomy. This is determined based on the requirements of each endograft as described in the instructions for use (IFU). The new ALTO system (Endologix, Irvin, CA, U.S.A.), can accommodate a great range of anatomies such as short necks and/or narrow access, but its unique design requires specific technical modifications during treatment of ruptured AAAs. AREAS COVERED: The standard double balloon technique has long been described and it is used to provide circulatory support during EVAR for ruptured AAA. While this technique is straightforward with the use of endografts with a traditional design, this would not be the case if one uses the ALTO system. In that case specific maneuvers would be required to treat AAA patients in an acute setting. EXPERT OPINION: The ALTO system although being able to treat AAAs with adverse anatomy, it may not be appropriate during treatment of ruptured AAA patients with profound hemodynamic instability. A careful evaluation of the individual's patient anatomy and hemodynamic condition is mandatory in order to decide the best endograft for each case.

Central venous catheters: Which, when and how.

Short-term or long-term CVCs are now considered the standard of practice for the administration of chemotherapy, fluid therapy, antibiotic therapy, and parenteral nutrition. Central venous access catheters are broadly divided into tunneled or non-tunneled catheters. Tunneled catheters can be further subdivided into totally implanted and totally not implanted devices. Device selection generally depends on various factors such as availability of peripheral veins, expected duration of therapy, and desired flow rate. Ultrasound-guided access is the safest technique for central venous access compared to the landmark technique and departments should strive to for a 100% ultrasound guided access. This review gives a basic overview of the differences of CVC catheters including PICCs, Hickman-catheters and port-catheters along with the criteria for CVC selection. It will also describe technical tips on placement of CVCs. Finally, it aims to highlight complications which are associated with CVC placement and options to treat or prevent them.

Effect of Sac Asymmetry, Neck and Iliac Angle on the Hemodynamic Behavior of Idealized Abdominal Aortic Aneurysm Geometries.

BACKGROUND: Abdominal aortic aneurysms (AAAs) are currently treated based on the universal maximum diameter criterion, but other geometric variables may play a role in the risk of rupture. The hemodynamic environment inside the AAA sac has been shown to interact with several biologic processes which can affect prognosis. AAA geometric configuration has a significant impact in the hemodynamic conditions that develop, which has only been recently realized, with implications for rupture risk estimations. We aim to perform a parametric study to evaluate the effect of aortic neck angulation, angle between the iliac arteries, and sac asymmetry (SA) on the hemodynamic variables of AAAs. METHODS: This study uses idealized AAA models and it is parametrized in terms of 3 quantities as follows: the neck angle, φ (°), iliac angle, θ (°), and SA (%), each of which accepts 3 different values, specifically φ = (0°, 30°, 60°), θ = (40°, 60°, 80°), and SA = (S, °SS, °OS), where the SA can either be on the same side with respect to neck (SS) or on the opposite side (OS). Time average wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and the velocity profile are calculated for different geometric configurations, while the percentage of the total surface area under thrombogenic conditions, using thresholds previously reported in the literature, is also recorded. RESULTS: In case of an angulated neck and a higher angle between iliac arteries, favorable hemodynamic conditions are predicted with higher TAWSS and lower OSI and RRT values. The area under thrombogenic conditions reduces by 16-46% as the neck angle increases from 0° to 60°, depending on the hemodynamic variable under consideration. The effect of iliac angulation is present but less pronounced with 2.5-7.5% change between the lower and the higher angle. The effect of SA seems to be significant for OSI, with a nonsymmetrical configuration being hemodynamically favorable, which in the presence of an angulated neck is more pronounced for the OS outline. CONCLUSIONS: Favorable hemodynamic conditions develop inside the sac of idealized AAAs with increasing neck and iliac angles. Regarding the SA parameter, asymmetrical configurations most often appear advantageous. Concerning the velocity profile the triplet (φ, θ, SA) may affect outcomes under certain conditions and thus should be taken into account when parametrizing the geometric characteristics of AAAs.

Late Neck Related Adverse Events are Rare Among Patients with Wide Aortic Neck Undergoing Endovascular Aneurysm Repair with the Ovation Endograft.

BACKGROUND: Patients with wide aortic necks undergoing Endovascular Aneurysm Repair (EVAR) have been shown to be at a higher risk for neck-related complications. We aim to examine outcomes of EVAR with an endograft exerting minimal outward pressure (Ovation-Endologix) in patients with a large baseline neck diameter. METHODS: We performed a retrospective single center study, including consecutive patients undergoing EVAR with the Ovation system from May 2011 to April 2021. Patients were divided in Groups 1 and 2 if the 20, 23, 26, 29 mm or the 34 mm proximal diameter main body was used, respectively. According to the instructions for use of the device, for neck diameters 27-30 mm the 34 mm main body is required. Primary endpoint was rate of neck related complications during follow-up, (type Ia endoleak, migration >10 mm and neck-related re-interventions) and rate of aortic neck dilatation (AND). AND was determined based on multiple aortic neck diameters that were recorded and compared between the 1-month computed tomography angiography (CTA) after EVAR and the last available follow-up CTA.Secondary endpoints were peri-procedural and follow-up outcomes such as endoleaks, reinterventions and overall mortality. RESULTS: In total 281 patients were included, 222 in Group 1 and 59 in Group 2. Patients in Group 2 presented significantly shorter neck length, higher neck angulation and more common reversed tapered configuration. Median follow-up was 36 months (Range: 6-106). Early and late type Ia endoleak was observed in 4 and 2 patients in each group, respectively (P = 0.063 and P = 0.195, respectively). Distal migration was observed in 2 patients in Group 2 and AND was recorded in 2 patients in each group (P = 0.195). Freedom from the primary endpoint was estimated at 98%, 94%, 94% at 12-, 36-, 60-months for Group 1 and at 98%, 95%, 86% for Group 2 (P-Value 0.266). Probability of survival was 95%, 86%, 75% at 12-, 36-, 60-months for Group 1 and 83%, 77%, 72% for Group 2 (P-Value 0.226).Multivariate regression analysis identified neither Group 1 versus Group 2 nor absolute value of aortic neck diameter as significant predictors of neck-related adverse events. Neck diameters did not display significant differences over time in any of the levels evaluated. CONCLUSIONS: EVAR with the Ovation endograft results in low rates of late neck related complications which is also true for patients with wide baseline aortic necks.

Dual-Energy Computed Tomography as an Adjunct in the Evaluation of Peripheral Chronic Total Occlusions: A Feasibility Study.

This study investigated the role of dual-energy computed tomography (CT) for lesion characterization in patients with peripheral arterial disease manifesting with chronic total occlusions (CTOs). Forty-one symptomatic patients with CTOs underwent dual-energy CT angiography before endovascular treatment. The lesions were subsequently analyzed in a dedicated workstation, and 2 indexes-dual-energy index (DEI) and effective Z (Zeff)-were calculated, ranging from 0.0027 to 0.321 and from 6.89 to 13.02, respectively. Statistical analysis showed a significant correlation between the DEI and Zeff values (P < .001). The interobserver intraclass correlation coefficient was 0.91 for the mean Zeff values and 0.86 for the mean DEI values. This technique could potentially provide useful information regarding the composition of a CTO.

Management of Inadvertent Arterial Catheterization during Central Venous Catheter Placement: A Case Series.

Percutaneous central venous catheterization, although a widely used technique in ICU patients worldwide, is not devoid of complications even under real-time ultrasound guidance. Arterial puncture is a well-recognized complication, while unintended subclavian or carotid artery cannulations during attempted central venous catheterization are infrequent, but documented complications with potentially deleterious consequences. Recently, endovascular balloon tamponade has emerged as the preferred initial approach to repair inadvertent arterial cannulations. Herein, we present a case series of inadvertent arterial catheterization during an attempted ultrasound-guided access of the right internal jugular and the left subclavian vein that were successfully managed with endovascular balloon tamponade.

Perfusion imaging techniques in lower extremity peripheral arterial disease.

Lower limb peripheral arterial disease (PAD) characterizes the impairment of blood flow to extremities caused by arterial stenoses or occlusions. Evaluation of PAD is based on clinical examination, calculation of ankle-brachial index and imaging studies such as ultrasound, CT, MRI and digital subtraction angiography. These modalities provide significant information about location, extension and severity of macrovasular lesions in lower extremity arterial system. However, they can be also used to evaluate limb perfusion, using appropriate techniques and protocols. This information may be valuable for assessment of the severity of ischemia and detection of hypoperfused areas. Moreover, they can be used for planning of revascularization strategy in patients with severe PAD and evaluation of therapeutic outcome. These techniques may also determine prognosis and amputation risk in patients with PAD. This review gives a basic overview of the perfusion techniques for lower limbs provided by imaging modalities such as ultrasound, CT, MRI, digital subtraction angiography and scintigraphy and their clinical applications for evaluation of PAD and revascularization outcome.

Direct Iliac Vein Stenting in Phlegmasia Cerulea Dolens Caused by May-Thurner Syndrome.

Phlegmasia cerulea dolens (PCD) is an uncommon but potentially limb-threatening complication of acute deep vein thrombosis. A 56-year-old male presented with PCD. Color Doppler ultrasonography revealed extensive thrombosis of the left superficial and common femoral and external and common iliac veins. After an unsuccessful iliofemoral thrombectomy, contrast-enhanced computed tomography revealed iliofemoral deep vein thrombosis due to May-Thurner syndrome (MTS). After the deployment of an inferior vena cava filter, the thrombotic occlusion was traversed with a guidewire and direct stenting was performed to achieve immediate recanalization. The patient was discharged two days after the procedure, demonstrating significant clinical improvement. MTS is a rare cause of PCD. Direct iliac vein stenting may be a safe and effective alternative treatment for rapid recanalization if percutaneous mechanical thrombectomy devices are unavailable.

Discrimination of High-Risk Type-2 Endoleak after Endovascular Aneurysm Repair through CT Perfusion: A Feasibility Study.

A type-2 endoleak after an endovascular aneurysm repair is the most prevalent type of endoleak, but as the clinical consequence of its diagnosis is uncertain, at present, management decisions are solely based on aneurysm sac growth. The aim of this study was to investigate the potential of various computed tomography perfusion parameters for their ability to distinguish high-risk type-2 endoleaks from low-risk type-2 endoleaks after an endovascular aneurysm repair.

The Use of a Suture Mediated Vascular Closure Device to Achieve Hemostasis following Arterial Access through Previously Implanted Synthetic Grafts.

BACKGROUND: Percutaneous endovascular aneurysm repair (EVAR) and peripheral interventions using the Perclose Proglide suture mediated system has not been adequately studied in patients with synthetic grafts at access sites. METHODS: We report the use of the Perclose Proglide in 10 patients in whom previously inserted synthetic grafts in the groin were punctured for arterial access (5 for peripheral interventions and 5 undergoing EVAR). In patients undergoing peripheral interventions a single device was used, while in patients undergoing EVAR 2 devices were employed per access site. The preclosing technique was used in every case. RESULTS: Hemostasis was achieved in all patients. No complications were observed except for a small laceration and a localized hemodynamically nonsignificant stenosis, without any clinical sequel. CONCLUSIONS: This small case series indicates the feasibility of percutaneous access with the Perclose Proglide system to perform EVAR and peripheral endovascular interventions in the presence of synthetic grafts in the groin, with promising outcomes.

Aggressive recurrence of Non-Hodgkin's Lymphoma after successful clearance of hepatitis C virus with direct acting antivirals.

The association of Non-Hodgkin lymphomas and Hepatitis C virus is well documented and antiviral treatments facilitate a virological and hematological response in the majority of HCV related Non-Hodgkin lymphomas. The recent years, direct acting antivirals have made cure possible almost for every HCV patient. Some concerns were raised as regards the frequency and the pattern of recurrence in HCV patients with HCC, treated with these agents. We present a patient with DLBCL, in remission after appropriate treatment, HCV cirrhosis that was cured with the new antivirals and shortly after SVR, he experienced a lethal lymphoma recurrence.

Endovascular Treatment of Malignant Superior Vena Cava Syndrome through Upper-Limb Access: A Comparison between Venous-Dedicated and Conventional Stents.

PURPOSE: To retrospectively evaluate the technical and clinical outcomes of superior vena cava (SVC) stent placement through upper-limb venous access in malignant SVC syndrome (SVCS) and compare the efficacy of different nitinol stent types. MATERIALS AND METHODS: Between 2006 and 2018, 156 patients (132 male; mean age, 62 y; age range, 33-81 y) underwent SVC stent placement for malignant obstructions through upper-limb venous access with 1 of 3 types of nitinol stent: 1 venous-dedicated (Sinus-XL stent) and 2 non-venous-dedicated (E-Luminexx Vascular Stent and Protégé GPS). Cases of common femoral vein access or non-nitinol stents were excluded from further analysis. The mean duration of follow-up was 8 mo. RESULTS: Technical success was achieved in 99.3% of cases. One patient died during the procedure as a result of cardiac tamponade. Balloon predilation was performed in 10 patients and postdilation in 126. Mean procedural time was 34.4 min (range, 18-80 min). Overall survival rates were 92.3%, 57.3%, and 26.8%, and overall primary patency rates were 94.5%, 84.8% and 79.6%, at 1, 6, and 12 mo, respectively. There were no statistically significant differences in primary patency rates between venous- and non-venous-dedicated stents or among different Stanford SVCS grading groups (P > .05). CONCLUSIONS: SVC stent placement through an upper-limb approach is a safe, fast, and effective technique. There is no evident benefit of venous-dedicated vs non-venous-dedicated stents in the treatment of malignant SVCS.

Dynamic CT perfusion imaging for type 2 endoleak assessment after endograft placement.

Endovascular repair of abdominal aortic aneurysm is a widely performed treatment method due to its minimal invasiveness, reduced need for intensive care unit (ICU), shorter hospitalization and lower 30-day morbidity and mortality compared to open surgery. Endoleak is the drawback of this procedure and is considered the main culprit for re-interventions due to the risk of late aneurysm sac growth and rupture. Type 2 endoleak (T2EL) is the most common type of endoleak which is also the most controversial regarding its management. The aim of this paper is to investigate the potential of dynamic contrast-enhanced CT for the assessment of T2EL after endovascular aneurysm repair using qualitative and quantitative image analysis of the aneurysmal sac.

The "Arm-to-Chest Tunneling" technique: A modified technique for arm placement of implantable ports or central catheters.

PURPOSE: Central venous catheters or "venous access devices" include totally implantable venous access devices or "ports," peripherally inserted central catheters, and tunneled lines. Venous access devices are now the standard of care in patients requiring long-term intravenous drug administration. Arm venous access device placement is a valuable option for vascular access yet often complicated or rendered practically impossible by the condition and size of peripheral veins. We describe a modification of the arm venous access device implantation technique that we use in our department in order to offer this option to our patients, regardless of their peripheral veins condition. METHODS: After ultrasound guided venous access of a suitable neck vein, we create a port pouch-in case of a totally implantable vascular access device-or a skin nick-in case of a venous access device-in the inner aspect of the mid-arm. Using a straight metal tunneler, we tunnel the line from the neck to the arm in two stages, externalizing and re-inserting the line into a skin nick made on the deltopectoral groove. We call this technique "Arm-to-Chest Tunneling" and use it to place venous access devices in the arm using a neck venous access. RESULTS: The Arm-to-Chest Tunneling technique allows us to use larger arm venous access device catheters irrespective of the arm veins condition. Thus, this technique has the advantages of arm venous access device placement, with the added benefit of saving the arm veins. CONCLUSION: The "Arm-to-Chest Tunneling" method offers the alternative to place a venous access device in a more discreet site in the arm, even in cases in which arm veins are inadequate.