Endoportal Radiofrequency Ablation and Stent Placement in Patients with Portal Vein Tumor Thrombosis from Hepatocellular Carcinoma: A Study on Feasibility and Safety.

Background: Hepatocellular carcinoma (HCC) is the most common type of liver cancer, with 10-40% of cases involving portal vein tumor thrombosis (PVTT), leading to poor outcomes and a short survival. The effectiveness of PVTT treatment in patients with HCC is still controversial. Methods: This prospective dual-center study cohort comprised 60 patients with HCC and PVTT who underwent PVR-EPRFA-ST using a novel intravascular radiofrequency system followed by vascular stent placement across the PVTT stenosed segment under fluoroscopy guidance. Results: PVR-EPRFA-ST was technically and clinically successful in 54/60 (90%) and 37/54 (68.5%) patients, respectively. The mean tumor size, PVTT length, post-ablation luminal diameter, and median duration of the recanalized PV patency were 8.6 ± 3.4 cm, 4.1 ± 2.1 cm, 10.3 ± 1.8 mm, and 13.4 months. Higher technical and clinical success rates were associated with a longer survival (177 ± 17.3 days, HR: 0.3, 95%CI 0.12-0.71, p = 0.04; and 233 ± 18.3 days, HR: 0.14, 0.07-0.27, p < 0.001). A shorter survival was associated with Child-Pugh C (HR: 2.7, p = 0.04), multiple tumors (HR: 1.81, p = 0.03), and PVTT length (HR: 1.16, p = 0.04). Conclusions: PVR-EPRFA-ST was feasible and effective for the treatment of selected patients with PVTT, especially in patients with Child-Pugh A/B, single tumors, or a shorter PVTT length.

Single Specialty-Operated Renal Stone Removal: Initial Experience from 3 Interventional Radiology Centers.

This retrospective analysis of the feasibility and safety of percutaneous renal stone removal using single-use flexible ureteroscopes was conducted at 3 academic centers. Twelve patients (58% men) underwent 14 percutaneous renal stone removal procedures between December 2021 and March 2023. All patients experienced symptom improvement and resolution of obstruction after stone removal. The procedural success rate was 92%. Only 1 patient required an additional stone removal procedure. No major adverse events occurred during or after the procedures. The percutaneous nephrostomy removal rate was 92%, with a median tube removal time of 5 weeks. The median procedural and pulsed fluoroscopy times were 106.5 and 16.3 minutes, respectively. Preliminary findings demonstrated that percutaneous renal stone removal using single-use endoscopes by interventional radiologists is feasible and safe.

Interventional Radiological Treatment of Orthotopic Heart Transplant Complications.

Orthotopic heart transplantation is a life-saving procedure that has substantially improved the lives of countless patients since its inception. However, there are several procedure-related complications that require prompt management. Interventional radiology, with its ever expanding toolkit, is a cornerstone of the multidisciplinary team following post-cardiac transplant patients. Percutaneous, endovascular therapy provides minimally invasive, safe, and effective treatments for immediate and delayed cardiac transplant complications and this paper serves to highlight the various management options interventional radiology can provide for orthotopic heart transplantation complications.

Predictors of endobronchial forceps utilization for inferior vena cava filter retrieval: when snare retrieval fails.

BACKGROUND: Endobronchial forceps are commonly used for complex IVC filter removal and after initial attempts at IVC filter retrieval with a snare have failed. Currently, there are no clear guidelines to help distinguish cases where primary removal should be attempted with standard snare technique or whether attempts at removal should directly be started with forceps. This study is aimed to identify clinical and imaging predictors of snare failure which necessitate conversion to endobronchial forceps. METHODS: Retrospective analysis of 543 patients who underwent IVC filter retrievals were performed at three large quaternary care centers from Jan 2015 to Jan 2022. Patient demographics and IVC filter characteristics on cross-sectional images (degree of tilt, hook embedment, and strut penetration, etc.) were reviewed. Binary multivariate logistic regression was used to identify predictors of IVC filter retrieval where snare retrieval would fail. RESULTS: Thirty seven percent of the patients (n = 203) necessitated utilization of endobronchial forceps. IVC filter hook embedment (OR:4.55; 95%CI: 1.74-11.87; p = 0.002) and strut penetration (OR: 56.46; 95% CI 20.2-157.7; p = 0.001) were predictors of snare failure. In contrast, total dwell time, BMI, and degree of filter tilt were not associated with snare failure. Intraprocedural conversion from snare to endobronchial forceps was significantly associated with increased contrast volume, radiation dose, and total procedure times (p < 0.05). CONCLUSION: IVC filter hook embedment and strut penetration were predictors of snare retrieval failure. Intraprocedural conversion from snare to endobronchial forceps increased contrast volume, radiation dose, and total procedure time. When either hook embedment or strut penetration is present on pre-procedural cross-sectional images, IVC filter retrieval should be initiated using endobronchial forceps. LEVEL OF EVIDENCE: Level 3, large multicenter retrospective cohort.

New Developments in Image-Guided Percutaneous Irreversible Electroporation of Solid Tumors.

PURPOSE OF REVIEW: This review will describe the various applications, benefits, risks, and approaches of conventional irreversible electroporation (IRE), as well as highlight the new technological developments of this procedure along with their clinical applications. RECENT FINDINGS: Minimally invasive image-guided percutaneous IRE ablation has emerged as a newer, non-thermal ablation technique for tumors in the solid organs, particularly within the liver, pancreas, kidney, and prostate. IRE allows for ablation near heat-sensitive structures, including major blood vessels and nerves, and is not susceptible to the heat sink effect. However, it is limited by certain requirements, such as the need for precise parallel placement of at least two probes with a maximum inter-probe distance of 2.5 cm to reduce the risk of arching phenomenon, the requirement for general anesthesia with muscle relaxant, and the need for cardiac synchronization. However, new technological advancements in the ablation system and image guidance tools have been introduced to improve the efficiency and efficacy of IRE. IRE is a safe and effective treatment option for solid tumor ablation within the liver, pancreas, kidney, and prostate. Compared with other ablation techniques, IRE has several advantages, such as the absence of heat sink effect and minimal injury to blood vessels and bile ducts while activating the immune system. Novel techniques such as H-FIRE, needle placement systems, and robotics have enhanced the accuracy and performance in placement of IRE probes. IRE can be especially beneficial when combined with chemotherapy, immunomodulation, and immunotherapy.

The Role of Mechanical Thrombectomy for Acute Massive Pulmonary Embolism in a Patient With Unilateral Lung Transplant and Atrial Septal Defect.

PURPOSE: The risk of thromboembolic disease is high in patients with lung transplantation and is associated with significant morbidity and mortality with single healthy transplanted lung. We present a case involving successful endovascular management of life-threatening acute massive pulmonary embolism (PE) in a patient with single lung transplant and atrial septal defect (ASD). CASE REPORT: A 65-year-old man with a history of interstitial lung disease status post single left orthotopic lung transplant in 2012 presented with acute massive PE and clot burden in the pulmonary arteries of the transplanted left lung. Severe right heart dysfunction, hemodynamic instability, and requirement for vasopressors persisted post systemic thrombolytic therapy. As a result, the patient underwent successful endovascular mechanical thrombectomy with immediate improvement in oxygen saturation and hemodynamic status. The procedure was performed without adverse outcomes or paradoxical embolization despite the presence of ASD. The right heart dysfunction resolved, the patient was extubated the next day, and was discharged to home 2 days post procedure. CONCLUSIONS: Endovascular mechanical thrombectomy was safely used to treat acute massive PE in a single transplanted lung in the presence of ASD. CLINICAL IMPACT: Endovascular mechanical thrombectomy could be safely utilized to treat patients with lung transplant and acute massive or submassive pulmonary embolism. However, safely of mechanical thrombectomy should be determined in case-based scenarios and based on time interval from transplantation to when the thrombectomy is required.

Greater cost without greater benefit: The need to refine transfer criteria for patients with severe acute pancreatitis.

BACKGROUND: Appropriate and timely care is essential in the management of severe acute pancreatitis (SAP). We hypothesized that transferred patients with SAP undergoing procedural intervention would have higher mortality compared to those managed directly at academic centers. METHODS: This was a retrospective analysis of Maryland's statewide claims database from 2009 to 2022 of adult patients admitted with a primary diagnosis of SAP (acute pancreatitis with organ failure). Patients were divided into three groups: those admitted directly from the emergency room to academic facilities (AD), non-academic facilities (NA), or transferred to academic facilities (TR). Procedural intervention included endoscopic, percutaneous image-guided, or surgical. The primary outcome was in-hospital mortality. Secondary outcomes were admission costs, length of stay (LOS), and intensive care unit (ICU) admission. RESULTS: There were 7,648 (48.9%) in the NA group, 6,682 (42.7%) in the AD group and 1,316 (8.4%) in the TR group. On regression analysis, odds of death were 0.57x lower in the NA group and 0.67x lower in the AD group compared to transfers (<0.001). Procedural intervention was not associated with increased mortality. Transferred patients had longer median LOS (11 vs NA = 5, AD = 6, p < 0.001), increased median cost of admission ($41k vs NA = $12k, AD = $17k, p < 0.001) and greater ICU admission (45.6% vs NA = 20.6%, AD = 23.9%, p < 0.001). CONCLUSION: Transferred patients have greater burden of illness and cost of care without evidence of improved outcomes in the management of SAP regardless of procedural intervention. Transfer criteria for patients with SAP must be further refined to reduce unnecessary transfers.

Potential Immunotherapy Targets for Liver-Directed Therapies, and the Current Scope of Immunotherapeutics for Liver-Related Malignancies.

Liver cancer, including hepatocellular carcinoma and intrahepatic cholangiocarcinoma, is increasing in incidence and mortality across the globe. An improved understanding of the complex tumor microenvironment has opened many therapeutic doors and led to the development of novel pharmaceuticals targeting cellular signaling pathways or immune checkpoints. These interventions have significantly improved tumor control rates and patient outcomes, both in clinical trials and in real-world practice. Interventional radiologists play an important role in the multidisciplinary team given their expertise in minimally invasive locoregional therapy, as the bulk of these tumors are usually in the liver. The aim of this review is to highlight the immunological therapeutic targets for primary liver cancers, the available immune-based approaches, and the contributions that interventional radiology can provide in the care of these patients.

Primary and Metastatic Lung Cancer: Rationale, Indications, and Outcomes of Thermal Ablation.

The widespread use of imaging as well as the efforts conducted through screening campaigns has dramatically increased the early detection rate of lung cancer. Historically, the management of lung cancer has heavily relied on surgery. However, the increased proportion of patients with comorbidities has given significance to less invasive therapeutic options like minimally invasive surgery and image-guided thermal ablation, which could precisely target the tumor without requiring general anesthesia or a thoracotomy. Thermal ablation is considered low-risk for lung tumors smaller than 3 cm that are located in peripheral lung and do not involve major blood vessels or airways. The rationale for ablative therapies relies on the fact that focused delivery of energy induces cell death and pathologic necrosis. Image-guided percutaneous thermal ablation therapies are established techniques in the local treatment of hepatic, renal, bone, thyroid and uterine lesions. In the lung, and specifically in the setting of metastatic disease, the 3 main indications for lung ablation are to serve as (1) curative intent, (2) as a strategy to achieve a chemo-holiday in oligometastatic disease, and (3) in oligoprogressive disease. Following these premises, the current paper aims to review the rationale, indications, and outcomes of thermal ablation as a form of local therapy in the treatment of primary and metastatic lung disease.

Characteristics of pivotal clinical trials of FDA-approved endovascular devices between 2000 and 2018: An interrupted time series analysis.

Background: The Food and Drug Administration (FDA) reviews safety, efficacy, and the quality of medical devices through its regulatory process. The FDA Safety and Innovation Act (FDASIA) of 2012 was aimed at accelerating the regulatory process for medical devices. Objectives: The purpose of our study was to (1) quantify characteristics of pivotal clinical trials (PCTs) supporting the premarket approval of endovascular medical devices and (2) analyze trends over the last two decades in light of the FDASIA. Methods: We surveyed the study designs of endovascular devices with PCTs from the US FDA pre-market approval medical devices database. The effect of FDASIA on key design parameters (e.g., randomization, masking, and number of enrolled patients) was estimated using an interrupted time series analysis (segmented regression). Results: We identified 117 devices between 2000-2018. FDASIA was associated with a decrease in double blinding (p < 0.0001) and a decrease in historical comparators (p < 0.0001). Discussion: Our results reveal an overall trend of decreased regulatory requirements as it relates to clinical trial characteristics, but a compensatory increased rate of post-approval across device classes. Furthermore, there was an emphasis on proving equivalence or non-inferiority rather than more use of active comparators in clinical trials. Medical device stakeholders, notably clinicians, must be aware of the shifting regulatory landscape in order to play an active role in promoting patient safety.

Safety and feasibility of a novel bi-directional portal vein access kit during transjugular intrahepatic portosystemic shunt creation.

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) creation remains as one of the more technically challenging endovascular procedures. Portal vein access from the hepatic vein often requires multiple needle passes, which increases procedure times, risk of complications, and radiation exposure. With its bi-directional maneuverability, the Scorpion X access kit may be a promising tool for easier portal vein access. However, the clinical safety and feasibility of this access kit has yet to be determined. MATERIALS AND METHODS: In this retrospective study, 17 patients (12 male, average age 56.6 ± 9.01) underwent TIPS procedure using Scorpion X portal vein access kits. The primary endpoint was time taken to access the portal vein from the hepatic vein. The most common indications for TIPS were refractory ascites (47.1%) and esophageal varices (17.6%). Radiation exposure, total number of needle passes, and intraoperative complications were recorded. Average MELD Score was 12.6 ± 3.39 (range: 8-20). RESULTS: Portal vein cannulation was successfully achieved in 100% of patients during intracardiac echocardiography-assisted TIPS creation. Total fluoroscopy time was 39.31 ± 17.97 min; average radiation dose was 1036.76 ± 644.15 mGy, while average contrast dose was 120.59 ± 56.87 mL. The average number of passes from the hepatic vein to the portal vein was 2 (range: 1-6). Average time to access the portal vein once the TIPS cannula was positioned in the hepatic vein was 30.65 ± 18.64 min. There were no intraoperative complications. CONCLUSIONS: Clinical utilization of the Scorpion X bi-directional portal vein access kit is both safe and feasible. Utilizing this bi-directional access kit resulted in successful portal vein access with minimal intraoperative complications. LEVEL OF EVIDENCE: Retrospective cohort.

Superior gluteal artery as a reliable back door to embolize mycotic pseudoaneurysm of an isolated Internal Iliac artery.

BACKGROUND: Antegrade access through the origin of the internal iliac and direct percutaneous access under cross-sectional imaging guidance are commonly used for embolization of internal iliac artery aneurysms, pseudoaneurysms, or endoleaks. Here, we report superior gluteal artery retrograde access to treat internal iliac artery mycotic pseudoaneurysm in a patient with failed direct percutaneous access. CASE PRESENTATION: We present a 65-year-old female with a history of diverticulitis and sigmoidectomy. Post-sigmoidectomy course was complicated by left common iliac artery (CIA) iatrogenic injury which required surgical ligation of the left CIA and graft placement. However, the graft was subsequently resection due to infection. Follow up CT imaging showed a 6 cm mycotic pseudoaneurysm (PSA) of the left internal iliac artery. Initially, the PSA sac was directly accessed and embolized under direct CT-guidance using Onyx. However, enlargement of the PSA sac was noted on one week follow-up CT images. Then, superior gluteal artery was accessed under ultrasound guidance, and the PSA sac and feeding vessels were re-embolized with coil and Onyx under fluoroscopy. CONCLUSION: Retrograde access through superior gluteal artery is a feasible and safe approach to embolize internal iliac aneurysms, pseudoaneurysms, or endoleaks, when the antegrade or direct percutaneous access is limited.

Image-Guided Percutaneous and Transarterial Therapies for Primary and Metastatic Lung Cancer.

Lung cancer is the leading cause of cancer mortality in the world. A significant proportion of patients with lung cancer are not candidates for surgery and must resort to other treatment alternatives. Rapid technological advancements in fields like interventional radiology have paved the way for valid treatment modalities like image-guided percutaneous and transarterial therapies for treatment of both primary and metastatic lung cancer. The rationale of ablative therapies relies on the fact that focused delivery of energy induces tumor destruction and pathological necrosis. Image-guided percutaneous thermal ablation therapies are established techniques in the local treatment of hepatic, renal, bone, thyroid, or uterine lesions. In the lung, the 3 main indications for lung ablation include local curative intent, a strategy to achieve a chemoholiday in oligometastatic disease, and recently, oligoprogressive disease. Transarterial therapies include a set of catheter-based treatments that involve delivering embolic and/or chemotherapeutic agents directed into the target tumor via the supplying arteries. This article provides a comprehensive review of the various techniques available and discusses their applications and associated complications in primary and metastatic lung cancer.

Collapse of inferior vena cava during complex filter retrieval with consequent intra-procedural systemic hypotension and bradycardia: a case report.

BACKGROUND: Prolonged dwelling time of inferior vena cava (IVC) filters has been shown to increase the need for the use of complex IVC filter retrieval techniques. In this report, we describe a case of complex retrieval of an IVC filter with prolonged dwelling time, which was temporarily accompanied by severe bradycardia and hypotension. CASE PRESENTATION: Fifty-nine-year-old male patient past medical history of morbid obesity, atrial fibrillation status post-ablation, obstructive sleep apnea, and end-stage renal disease presented for IVC filter retrieval 16 years after placement. When the IVC filter was covered by sheaths, and the IVC was temporarily collapsed and occluded, the patient developed severe bradycardia and hypotension without compensatory tachycardia. Contrast injection through the common femoral vein sheath showed complete occlusion of IVC while the IVC filter was covered by both sheaths, likely due to the embedment of the IVC filter in the wall by extensive fibrinous tissues. IVC filter was successfully retrieved, and the blood pressure and heart rate were improved immediately afterward. A large non-occlusive IVC thrombus was identified on the final venogram, which was aspirated using a mechanical thrombectomy device. CONCLUSION: Complex retrieval of IVC filters with prolonged dwelled time can result in acute severe bradycardia and hypotension due to vasovagal reaction, acute collapse, and occlusion of IVC in the setting of IVC filter embedment in the wall by extensive fibrinous tissues.

Portal Vein Embolization: Rationale, Techniques, and Outcomes to Maximize Remnant Liver Hypertrophy with a Focus on Contemporary Strategies.

Hepatectomy remains the gold standard for curative therapy for patients with limited primary or metastatic hepatic tumors as it offers the best survival rates. In recent years, the indication for partial hepatectomy has evolved away from what will be removed from the patient to the volume and function of the future liver remnant (FLR), i.e., what will remain. With this regard, liver regeneration strategies have become paramount in transforming patients who previously had poor prognoses into ones who, after major hepatic resection with negative margins, have had their risk of post-hepatectomy liver failure minimized. Preoperative portal vein embolization (PVE) via the purposeful occlusion of select portal vein branches to promote contralateral hepatic lobar hypertrophy has become the accepted standard for liver regeneration. Advances in embolic materials, selection of treatment approaches, and PVE with hepatic venous deprivation or concurrent transcatheter arterial embolization/radioembolization are all active areas of research. To date, the optimal combination of embolic material to maximize FLR growth is not yet known. Knowledge of hepatic segmentation and portal venous anatomy is essential before performing PVE. In addition, the indications for PVE, the methods for assessing hepatic lobar hypertrophy, and the possible complications of PVE need to be fully understood before undertaking the procedure. The goal of this article is to discuss the rationale, indications, techniques, and outcomes of PVE before major hepatectomy.