Transcatheter Aortic Valve Implantation (TAVI) Planning with Dual-Layer Spectral CT Using Virtual Monoenergetic Image (VMI) Reconstructions and 20 mL of Contrast Media.

Transcatheter aortic valve implantation (TAVI) is a less invasive alternative to surgical implantation and its implementation is progressively increasing worldwide. We routinely perform pre-procedural aortic angiography CT to assess aortic dimensions and vascular anatomy. This study aims to evaluate the image quality of CTA for TAVI planning using dual-layer spectral CT, with virtual monoenergetic image reconstructions at 40 keV. Thirty-one patients underwent a CTA protocol with the injection of 20 mL of contrast media. Image quality was assessed by measuring the mean density in Hounsfield Units (HU), the signal-to-noise ratio, and the contrast-to-noise ratio in VMI reconstructions. Additionally, a blinded subjective analysis was conducted by two observers. The results showed significant enhancement at all sampled vascular levels with a gradual decrease in HU from proximal to distal regions. Favourable subjective ratings were given for all parameters, with greater variability in the evaluation of iliac axes. A significant negative correlation (p < 0.05) was observed between BMI and CA at all vascular levels, indicating reduced contrast enhancement with increasing BMI. Spectral CT, along with reducing iodine load, allows for obtaining high-quality images without a significant increase in noise. The reduction in iodine load can have positive implications in clinical practice, improving patient safety and resource efficiency.

Pulmonary Artery Pseudoaneurysms Embolization: Bicentric Experience and Review of the Literature.

The purpose of this bicentric case series was to report the safety, efficacy, and clinical outcome of transcatheter embolization in pulmonary artery pseudoaneurysms (PAPAs). Between January 2016 and June 2021, eight patients with PAPA were subjected to transcatheter embolization. The total number of patients was eight, of which five were female, with a mean age of 62 ± 14 years (average ± standard deviation). Etiology was traumatic in 2/8 cases and iatrogenic in 6/8 cases (after positioning a Swan-Ganz catheter in 5/6 cases and a temporary pacemaker in the latter case). In a single case, the PAPA was incidentally discovered during a routine X-ray, in the remaining 7 cases, the procedure was performed in emergency settings. PAPA embolization was performed using detachable coils alone in 3 cases; coils and glue in 1 case; coils, glue, and vascular plug in 1 case; coils and non-adhesive liquid embolic agents (Onyx and Squid respectively) in 2 cases; and non-adhesive liquid embolic agent alone (Onyx) in 1 case. No peri-procedural or post-procedural complications were recorded. Both the technical and clinical success rates were 100.0%. In conclusion, endovascular embolization is a technically feasible and safe therapeutic option for patients with PAPAs.

Type II single coronary artery from right aortic sinus, retro-aortic left coronary artery and dual LAD: a rare association of coronary arterial variations.

PURPOSE: The coronary arterial tree has a wide range of possible benign anatomical variations. It is important to differentiate them from coronary arterial anomalies, which can remain asymptomatic or in some cases lead to sudden death if undiagnosed. METHODS: A 42-year-old female patient with a transient ST depression in right precordial leads performed an ECG-gated computed tomography angiography with dual layer spectral CT (IQon Elite Spectral CT, Philips, Amsterdam, The Netherlands) at Circolo Hospital of Varese. RESULTS: A rare variant was observed and studied: a single common trunk arising from the right sinus of Valsalva which branches into a right coronary artery, a left anterior descending artery with malignant course and a left main with a retroaortic course; the left main gives origin to a dual anterior interventricular artery ("Dual LAD") and a left circumflex artery. CONCLUSIONS: This type of variation was never described in the English literature. Identifying this variant is crucial for potential ischemic complications during sports activities or with the onset of atherosclerotic disease.

Internal Iliac Artery Embolization within EVAR Procedure: Safety, Feasibility, and Outcome.

BACKGROUND: This study is focused on Internal Iliac Artery (IIA) embolization in patients undergoing Endovascular Aneurysm Repair (EVAR). Our aims were: to establish the feasibility of the procedure; to assess the presence of endoleak (EL) and increase in the size of the sac at follow-up; to define the need for reintervention; and to evaluate mortality rate. METHODS: In this retrospective single-center study, EVAR-treated patients with an embolization of IIA were chosen. Coils and vascular plug were used as embolizing agents. RESULTS: A total of 49 participants were enrolled in the study (48 men and one woman) with a median age of 76 ± 12 years. Patients had no early EL in 87.75% of cases, 8.16% had type 1a EL, 2.04% type 1b EL, and 2.04% type 2 EL, with a comprehensive technical success of 95.91%. In the follow-up, at 1 month 72.22% remained without EL, at 6 months 70.97%, and at 1 year 81.48%. In the same period, the trend of type 1 EL was 5.56% (1 month), 3.23% (6 months), and 0% (1 year). For EL type 2: 22.22% at 1 month, 25.81% at 6 months, and 16.7% at 1 year. The overall mortality was 35.58% and the re-intervention rate was 16.33%. CONCLUSIONS: IIA embolization is a feasible and safe procedure. The presence of EL is not superior to EVAR procedures that do not involve embolization.

Non-Adhesive Liquid Embolic Agents in Extra-Cranial District: State of the Art and Review of the Literature.

This review focuses on the use of "new" generation of non-adhesive liquid embolic agents (NALEA). In literature, non-adhesive liquid embolic agents have mainly been used in the cerebral district; however, multiple papers describing the use of NALEA in the extracranial district have been published recently and the aim of this review is to explore and analyze this field of application. There are a few NALEA liquids such as Onyx, Squid, and Phil currently available in the market, and they are used in the following applications: mainly arteriovenous malformations, endoleaks, visceral aneurysm or pseudoaneurysm, presurgical and hypervascular lesions embolization, and a niche of percutaneous approaches. These types of embolizing fluids can be used alone or in combination with other embolizing agents (such as coils or particles) so as to enhance its embolizing effect or improve its possible defects. The primary purpose of this paper is to evaluate the use of NALEAs, predominantly used alone, in elective embolization procedures. We did not attempt a meta-analysis due to the data heterogeneity, high number of case reports, and the lack of a consistent follow-up time period.

Transcatheter Arterial Embolization in Acute Non-Variceal Gastrointestinal Bleedings: A Ten-Year Single-Center Experience in 91 Patients and Review of the Literature.

OBJECTIVE: To report the safety and efficacy of trans-arterial embolization (TAE) for upper gastrointestinal bleeding (UGIB) and lower gastrointestinal bleeding (LGIB) due to different etiologies in 91 patients for ten years. METHODS: A retrospective analysis of GIB treated between January 2010 and December 2020 was performed. TAE was performed using different embolic agents (coils, particles, glue, gelatin sponge, and EVOH-based agents). Technical success, secondary technical success, clinical success, and complications were evaluated. RESULTS: Technical success was achieved in 74/91 (81.32%) patients. Seventeen patients (18.68%) required re-intervention. Secondary technical success was achieved in all cases (100.0%). Clinical success was achieved in 81/91 patients (89.01%). No major complications were recorded; overall, minor complications occurred in 20/91 patients. CONCLUSIONS: TAE is a technically feasible and safe therapeutic option for patients with GIB from a known or blind anatomic source where endoscopic therapy has failed or is deemed unfeasible.

Visceral Artery Aneurysms Embolization and Other Interventional Options: State of the Art and New Perspectives.

Visceral artery aneurysms (VAAs) are rare, usually asymptomatic and incidentally discovered during a routine radiological examination. Shared guidelines suggest their treatment in the following conditions: VAAs with diameter larger than 2 cm, or 3 times exceeding the target artery; VAAs with a progressive growth of at least 0.5 cm per year; symptomatic or ruptured VAAs. Endovascular treatment, less burdened by morbidity and mortality than surgery, is generally the preferred option. Selection of the best strategy depends on the visceral artery involved, aneurysm characteristics, the clinical scenario and the operator's experience. Tortuosity of VAAs almost always makes embolization the only technically feasible option. The present narrative review reports state of the art and new perspectives on the main endovascular and other interventional options in the treatment of VAAs. Embolization techniques and materials, use of covered and flow-diverting stents and percutaneous approaches are accurately analyzed based on the current literature. Visceral artery-related considerations and targeted approaches are also provided and discussed.

Vacuum-assisted mechanical thrombectomy in extensively occlusive thrombosis of dialysis arteriovenous grafts with indigo system.

PURPOSE: To present a selected series of extensively occlusive thrombosis of arteriovenous graft treated with the Penumbra's Indigo System. MATERIALS AND METHODS: Ten patients with acute (within 72 h) extensively occlusive thrombosis of arteriovenous graft (mean extension = 30.1 (range = 15-45) cm) were treated at our institution with the Indigo System. Of the 10 cases, thrombosis was extended to venous outflow in 7 cases and to both arterial inflow and venous outflow in 3 cases. RESULTS: Both anatomic and clinical success were achieved in 8 of the 10 procedures (80.0%). In the 2 cases of technical failure, the patients underwent surgical thrombectomy with the finding of arteriovenous graft exhaustion, which was then replaced. The 6-month primary patency, primary-assisted patency, and secondary patency rates were 37.5% (3/8), 50.0% (4/8), and 62.5% (5/8). We reported 2 complications (one minor and one major adverse event). CONCLUSION: Percutaneous mechanical thrombectomy aspiration with Indigo System is a relatively safe and effective procedure and can be used even in extensively thrombosed arteriovenous graft.

Efficacy of Primary Stent-Graft Placement in the Treatment of Vascular Access Graft Outflow Tract Stenosis.

PURPOSE: The aim of this study is to present our personal experience using covered nitinol stent-graft in the treatment of outflow tract stenosis of arteriovenous grafts (AVGs) for hemodialysis access. MATERIALS AND METHODS: Between May 2015 and October 2017, we retrospectively evaluated 36 (24 males, 12 females; mean age: 65.6 years) patients with AVGs on hemodialysis who underwent percutaneous angioplasty followed by endovascular stent-graft deployment for the treatment of stenosis of the venous outflow of the AVG. Indication for treatment included early restenosis (<3 months after previous percutaneous transluminal angioplasty [PTA]), long stenosis (stenoses >50% extending for a length >5 cm), and recoil of the stenosis after PTA performed with a noncompliant high-pressure balloon. Of 36 patients, 27 (75%) required surgical thrombectomy prior to endovascular procedure. Technical success, clinical success, primary and secondary patency, and safety were evaluated. RESULTS: Technical success was 100%, and clinical success was 94.4%. Primary patency was 94.4%, 72.2%, 63%, 45.9%, and 45.9% at 1, 3, 6, 12, and 18 months (average: 215 days, range: 9-653 days); secondary patency was 94.4% and 86.1% at 1 and 3 months; 80.4% at 6, 12, and 18 months; and 53.6% at 24 months (average: 276.8 days, range: 9-744 days). No deaths were registered. CONCLUSIONS: In selected cases, the use of stent-graft represents an effective and safe solution for the treatment of stenotic complications of the venous outflow of AVGs, even in the setting of access thrombosis.

First use of a scoring balloon to perform Oddi sphincteroplasty for biliary stones.

Balloon sphincteroplasty is a well-known procedure for the treatment of biliary stones. Scoring balloons are characterized by rigid tangential elements that provide focal force, achieving a greater pressure than normal balloons. We report the first (to our knowledge) use of a scoring balloon to perform sphincteroplasty in 4 cases of elderly people presenting with symptomatic choledocholithiasis. In all cases we achieved complete common bile duct clearing with good symptom relief. No procedural complications were observed.

Video-assisted thoracoscopic resection of lung nodules localized with a hydrogel plug.

OBJECTIVES: Computed tomography (CT)-guided hydrogel plug deployment was recently proposed for lung nodule preoperative localization and simultaneous prevention of pneumothorax. We analysed our initial experience with CT-guided hydrogel plug localization of lung nodules in patients undergoing video-assisted thoracoscopic (VATS) resection. METHODS: We retrospectively evaluated the medical notes from 27 consecutive patients (mean age 68 ± 11 SD years; men 74%) undergoing VATS lung wedge resection for biopsy or definitive treatment of 28 small pulmonary nodules (malignant 82%) at a single institution between October 2017 and July 2018. Difficult intraoperative nodule localization was anticipated with a lesion <10 mm, a depth from pleura:size ratio >1, ground-glass opacity or the judgement of the operating surgeon. All lesions were preoperatively marked by deployment of a CT-guided hydrogel plug. Study end points were frequency of postlocalization pneumothorax; feasibility of delayed surgery; rate of localization of intraoperative nodule and rate of successful VATS resection. RESULTS: The mean sizes of the solid nodules (n = 24) and of the ground-glass opacities (n = 4) were, respectively, 10.4 ± 3.4 mm and 16.0 ± 6.2 mm. One (4%) hydrogel plug marking procedure caused a clinically relevant pneumothorax. Nodule resection was scheduled flexibly as required by patient management/operating room scheduling: same day (11 nodules) or delayed [median 6 days (range 1-60 days)]; (17 nodules). All nodules were localized intraoperatively: 25 (89%) by hydrogel plug; 3 (11%) by palpation and pleural puncture hole visible after plug displacement. All nodules were completely excised by VATS, without complications. CONCLUSIONS: CT-guided hydrogel plug marking was valuable for VATS localization and resection of challenging lung nodules. The plug minimized clinically relevant pneumothoraxes and allowed flexible surgical schedules.

Hypoplasia of right renal vein with aberrant drainage into ipsilateral spermatic vein: Case report.

The objective of this study was to describe a case of marked hypoplasia of the right renal vein with drainage into ipsilateral gonadal vein. A 66-year-old man, known for hypertension and previous smoking, underwent an abdominal ultrasound exam, which detected a juxtarenal aortic aneurysm. Computed tomography scan confirmed the presence of the aortic aneurysm; furthermore it showed an abnormal right kidney venous drainage consistent in a dilated and tortuous vein, which originated at the hilar region, heading caudally and joining the right spermatic vein at level of aortic carrefour. A thin vein-located more cranially with mild and late contrast enhancement-was also demonstrated from right kidney hilum to inferior vena cava, probably representing a remnant of the right main renal vein. To our knowledge, this anatomic variant was never reported in the peer-reviewed literature.

The Evaluation of Aortic Diameter Changes During Long-Term Follow-Up After Endovascular Treatment of Acute Blunt Traumatic Thoracic Aortic Injuries.

PURPOSE: To evaluate the variations in aortic diameters and long-term results in patients who underwent thoracic endovascular aortic repair (TEVAR) for acute blunt traumatic thoracic aortic injuries (BTTAIs). MATERIALS AND METHODS: We retrospectively evaluated 23 patients with a mean age of 39 years (range: 17-74 years) who underwent TEVAR for BTTAI between October 2000 and November 2014. All of the patients underwent computed tomography angiography (CTA) before hospital discharge as a baseline imaging for the subsequent follow-up examinations. The technical success, overall survival, and complications were evaluated. Furthermore, the aortic diameters outside of the stent-graft (1 cm proximal and 1 cm distal to the stent-graft) and the aortic diameters within the stent-graft (2 cm distal to the proximal end and 2 cm proximal to the distal end) were assessed. The diameters at baseline on CTA were compared with those of the latest available follow-up examination. RESULTS: Technical success was 100% with a mean follow-up of 65.4 months (range: 12-171 months). No death was registered, and 2 (8.7%) of 23 endograft-related complications (1 stent-graft distal infolding and 1 endoleak 2 and 4 months after the procedure, respectively) were observed. An increase in aortic diameter either proximal or distal to the stent-graft (mean value 0.7 and 0.5 mm, respectively) or within the stent-graft (mean value of 0.5 mm for both proximal and distal diameters) was registered (mean follow-up at 65.4 months, range: 12-171 months). CONCLUSION: Aortic dilatation following TEVAR for BTTAI is minimal during long-term follow-up. Endovascular treatment represents a durable and safe option in acute BTTAIs.

Thoracic Endovascular Aortic Repair for Embolizing Total Occlusion of the Descending Aorta due to Aortic Sarcoma.

Primary malignant tumors of the aorta are extremely rare, and the diagnosis is difficult from the clinical onset. Accordingly to the principles of cancer surgery, "en bloc" resection of the tumor-involved aorta and graft interposition is the gold standard, but it is still technically challenging and comorbidities may rule out some patients from an operative treatment. Thoracic endovascular aortic repair has been reported anecdotally, but it is an ease and rapid alternative in urgent circumstances and proved to be effective to relieve symptoms caused by these lesions. Unfortunately, no matter what is the type of histology or immunohistochemistry, or the type of treatment, the prognosis of aortic malignancies is very poor. Nevertheless, an operative treatment strategy which includes surgical resection and chemotherapy or radiation had long survival than patients treated with a single modality. We report a case of acute mesenteric syndrome caused by an occlusive and embolizing thrombus of the descending thoracic aorta caused by primary aortic sarcoma treated with thoracic endovascular aortic repair.

Duplex collecting system in a pelvic kidney - an unusual combination.

Pelvic kidney is a relatively common renal malformation as well as duplex kidney; however, the unilateral coexistence of these abnormalities is not frequently found. We present a case of a young woman with a history of hypertension in whom a pelvic and dysmorphic left kidney was discovered during ultrasound examination performed for the study of the renal arteries. Magnetic resonance imaging and computed tomography imaging revealed a duplex pelvic kidney. This combination is very rare; we have not found a similar case reported in the literature.

Current role of microwave ablation in the treatment of small hepatocellular carcinomas.

Percutaneous radiofrequency ablation (RFA) can be as effective as surgical resection in terms of overall survival and recurrence-free survival rates in patients with small hepatocellular carcinoma (HCC). Effectiveness of RFA is adversely influenced by heat-sink effect. Other ablative therapies could be considered for larger tumors or for tumors located near the vessels. In this regard, recent improvements in microwave energy delivery systems seem to open interesting perspectives to percutaneous ablation, which could become the ablation technique of choice in the near future. Microwave ablation (MWA) has the advantages of possessing a higher thermal efficiency. It has high efficacy in coagulating blood vessels and is a relatively fast procedure. The time required for ablation is short and the shape of necrosis is elliptical with the older systems and spherical with the new one. There is no heat-sink effect and it can be used to ablate tumors adjacent to major vessels. These factors yield a large ablation volume, and result in good local control and fewer complications. This review highlights the most relevant updates on MWA in the treatment of small (<3 cm) HCC. Furthermore, we discuss the possibility of MWA as the first ablative choice, at least in selected cases.

Thoracic endovascular aortic repair for blunt thoracic aortic injuries in complex aortic arch vessels anatomies.

The aim of this study is to report the use of thoracic endovascular aortic repair (TEVAR) in blunt thoracic aortic injuries (BTAIs) presenting with complex anatomies of the aortic arch vessels. Two patients were admitted to our hospital for the management of BTAI. Anomalies were as follow: aberrant right subclavian artery (n = 1) and right-sided aortic arch with 5 vessels anatomy variant (n = 1). TEVAR was accomplished using parallel graft with periscope configuration in the patient with the aberrant right subclavian artery. At 12-month follow-up, computed tomography angiographies confirmed the exclusion of the BTAI, the stability of the endograft, the resolution of the pseudoaneurysm, and the patency of the parallel endograft. Aortic arch vessels variants and anomalies are not rare, and should be recognized and studied precisely to plan the most appropriate operative treatment. TEVAR proved to be effective even in complex anatomies.

Optical fiber sensors-based temperature distribution measurement in ex vivo radiofrequency ablation with submillimeter resolution.

Radiofrequency thermal ablation (RFTA) induces a high-temperature field in a biological tissue having steep spatial (up to 6°C∕mm) and temporal (up to 1°C∕s) gradients. Applied in cancer care, RFTA produces a localized heating, cytotoxic for tumor cells, and is able to treat tumors with sizes up to 3 to 5 cm in diameter. The online measurement of temperature distribution at the RFTA point of care has been previously carried out with miniature thermocouples and optical fiber sensors, which exhibit problems of size, alteration of RFTA pattern, hysteresis, and sensor density worse than 1 sensor∕cm. In this work, we apply a distributed temperature sensor (DTS) with a submillimeter spatial resolution for the monitoring of RFTA in porcine liver tissue. The DTS demodulates the chaotic Rayleigh backscattering pattern with an interferometric setup to obtain the real-time temperature distribution. A measurement chamber has been set up with the fiber crossing the tissue along different diameters. Several experiments have been carried out measuring the space-time evolution of temperature during RFTA. The present work showcases the temperature monitoring in RFTA with an unprecedented spatial resolution and is exportable to in vivo measurement; the acquired data can be particularly useful for the validation of RFTA computational models.

Fiber-optic chirped FBG for distributed thermal monitoring of ex-vivo radiofrequency ablation of liver.

A linearly chirped fiber Bragg grating (LCFBG) has been used as a temperature sensor for online monitoring of radiofrequency thermal ablation (RFTA). The LCFBG acts as a distributed sensor, with spatial resolution of 75 µm. A white-light setup that records the LCFBG spectrum estimates the temperature profile in real time. Three RFTA experiments have been performed ex-vivo on porcine liver measuring the radial temperature distribution during the heating process. The analysis of thermal maps quantifies the spatial heat distribution along the measurement axis and determines the ablation efficiency.

Fiber-optic combined FPI/FBG sensors for monitoring of radiofrequency thermal ablation of liver tumors: ex vivo experiments.

We present a biocompatible, all-glass, 0.2 mm diameter, fiber-optic probe that combines an extrinsic Fabry-Perot interferometry and a proximal fiber Bragg grating sensor; the probe enables dual pressure and temperature measurement on an active 4 mm length, with 40 Pa and 0.2°C nominal accuracy. The sensing system has been applied to monitor online the radiofrequency thermal ablation of tumors in liver tissue. Preliminary experiments have been performed in a reference chamber with uniform heating; further experiments have been carried out on ex vivo porcine liver, which allowed the measurement of a steep temperature gradient and monitoring of the local pressure increase during the ablation procedure.