Invasive Vascular Interventions Research Articles

Does dexamethasone therapy affect intimal hyperplasia after injury in rat abdominal aorta models?

Intimal hyperplasia is a normal adaptive feature of arteries in response to injuries, which include invasive vascular interventions. Its development limits the long-term success of bypass grafts. Various pharmacological agents have been successfully employed in experimental models to reduce the degree of intimal hyperplasia. In our study, we investigated the efficacy of dexamethasone in reducing intimal hyperplasia in rat abdominal aortas after partial transection and primary repair. In this study, 20 Wistar Albino rats were randomly selected and divided into four groups to compare the effects of low- and high-dose dexamethasone on intima and media thickness compared to the control. Group A (n=5) was the control group, where only skin incision and laparotomy were performed. For Group B (n=5), a median laparotomy was performed, the abdominal aorta was partially transected, and repaired with an 8.0 prolene suture. Doses of 0.1 mg/kg and 0.2 mg/kg dexamethasone were administered in Group C (n=5) and Group D (n=5), respectively. After two weeks, all rats were euthanized, and the repaired abdominal aortas were excised and examined histopathologically. Intima and media thicknesses were measured using the 'Olympus AnalySIS 5' program (Olympus Corporation, Japan) after digital photos were taken. Based on the measurements, we demonstrated that after transection and repair of the abdominal aorta, the intima/media ratio was not significantly different between the low-dose dexamethasone and non-dexamethasone groups. The intima/media ratio was significantly lower in the high-dose dexamethasone group than in the non-dexamethasone and low-dose dexamethasone groups. After vascular interventions, dexamethasone treatment may reduce intimal hyperplasia and increase patency by providing vascular remodeling.

Multi-mode information fusion navigation system for robot-assisted vascular interventional surgery

BackgroundMinimally invasive vascular intervention (MIVI) is a powerful technique for the treatment of cardiovascular diseases, such as abdominal aortic aneurysm (AAA), thoracic aortic aneurysm (TAA) and aortic dissection (AD). Navigation of traditional MIVI surgery mainly relies only on 2D digital subtraction angiography (DSA) images, which is hard to observe the 3D morphology of blood vessels and position the interventional instruments. The multi-mode information fusion navigation system (MIFNS) proposed in this paper combines preoperative CT images and intraoperative DSA images together to increase the visualization information during operations.ResultsThe main functions of MIFNS were evaluated by real clinical data and a vascular model. The registration accuracy of preoperative CTA images and intraoperative DSA images were less than 1 mm. The positioning accuracy of surgical instruments was quantitatively assessed using a vascular model and was also less than 1 mm. Real clinical data used to assess the navigation results of MIFNS on AAA, TAA and AD.ConclusionsA comprehensive and effective navigation system was developed to facilitate the operation of surgeon during MIVI. The registration accuracy and positioning accuracy of the proposed navigation system were both less than 1 mm, which met the accuracy requirements of robot assisted MIVI.

S2176 Small Bowel Varices: A Covert Source of Overt Bleeding

INTRODUCTION: Alcoholic cirrhosis is one of the most common causes of liver failure, accounting for millions of hospitalizations each year. Although esophageal, gastric, and rectal varices are extensively described as a result of portal hypertension, small bowel varices (SBV) are rarely implicated as a source of GI bleeding. This report describes a unique case of isolated SBV resulting in overt GI hemorrhage. CASE DESCRIPTION/METHODS: A 54-year-old female with a history of alcoholic cirrhosis decompensated by esophageal varices, hepatic encephalopathy, and abdominal ascites (MELD-Na 19) presented to the ED after multiple episodes of melena and hematochezia. The patient had previously undergone transjugular portosystemic shunting (TIPS) for recurrent variceal bleeding. The patient underwent an EGD which showed mild portal hypertensive gastropathy but no gastric or esophageal varices. Her colonoscopy was unremarkable. Given ongoing bleeding, the patient underwent a capsule endoscopy which revealed fresh blood with clots two-thirds (65%) of the way through the jejunum. A CT angiography revealed a portosystemic shunt between the superior mesenteric vein and the common femoral vein near the jejunum. Interventional radiology performed a catheter guided coil and glue embolization of the venous malformation and created a new portosystemic shunt. The patient’s melena and hematochezia ceased, and she was safely discharged home. DISCUSSION: Caused by portal hypertension, SBV are rare and infrequently implicated in significant GI hemorrhage. This case is unique in that the patient had no gastric, esophageal, or rectal varices. Isolated SBV are described anecdotally in the literature and extremely unlikely to manifest clinically. In addition, this case highlights the potential utility for inpatient video capsule endoscopy (VCE). In a patient with persistent GI bleeding with normal endoscopy and colonoscopy should certainly be considered for a deeper luminal exam. Furthermore, the definitive management of SBV is not well defined. While the mainstay of treatment is supportive care, minimally invasive vascular interventions provide an exciting option for management.

Microbiological and clinical profile of infective endocarditis patients: an observational study experience from tertiary care center Karachi Pakistan

BackgroundThe study analyzed microbiological and antimicrobial susceptibility profile of organisms isolated from patients with infective endocarditis (2015–17) and compared disease outcomes in cohorts of endocarditis patient with history of prior invasive vascular intervention (high risk group) vs those without (native valve group). We hypothesized that high risk group would be more likely to have severe disease outcomes.MethodsThis was a prospective cohort study (2015–17). All blood and cardiac tissue samples of enrolled patients suspected of endocarditis according to modified Duke’s criteria were followed for microbiological and antimicrobial susceptibility profile. The high risk group was compared with the native valve group with 90 day follow up to determine difference in clinical course and outcome in terms of disease severity (defined as any patient with endocarditis undergoing surgical management, readmission or dying). The data was analyzed using SPSS 21.0 software and chi-square test. 90 day mortality was calculated using Kaplan Meier survival curves.ResultsTotal 104 patients with endocarditis were enrolled. Overall culture positivity rate was 71.2%. Streptococcus species were the most common isolate (36.7%), followed by S. aureus (17.3%) cases. In Streptococcus species, 14.2% showed intermediate susceptibility to penicillin. Thirty six patients were included in the cohort analysis. A poor outcome was seen in 85.7% high risk group as compared to 50% of native valve group. The overall mortality rate was 19.4%.ConclusionsWe found Streptococcus species to be the predominant pathogen for endocarditis overall. However Staphylococcus aureus predominated native valve group. High risk group showed more complicated clinical course.

Management of percutaneous coronary intervention complications

### Learning objectives In the 40 years since Gruntzig’s first angioplasty,1 percutaneous coronary intervention (PCI) has become one of the most frequently performed therapeutic interventions in medicine.2 Devices and techniques...

Polymeric endovascular strut and lumen detection algorithm for intracoronary optical coherence tomography images.

Polymeric endovascular implants are the next step in minimally invasive vascular interventions. As an alternative to traditional metallic drug-eluting stents, these often-erodible scaffolds present opportunities and challenges for patients and clinicians. Theoretically, as they resorb and are absorbed over time, they obviate the long-term complications of permanent implants, but in the short-term visualization and therefore positioning is problematic. Polymeric scaffolds can only be fully imaged using optical coherence tomography (OCT) imaging-they are relatively invisible via angiography-and segmentation of polymeric struts in OCT images is performed manually, a laborious and intractable procedure for large datasets. Traditional lumen detection methods using implant struts as boundary limits fail in images with polymeric implants. Therefore, it is necessary to develop an automated method to detect polymeric struts and luminal borders in OCT images; we present such a fully automated algorithm. Accuracy was validated using expert annotations on 1140 OCT images with a positive predictive value of 0.93 for strut detection and an R2 correlation coefficient of 0.94 between detected and expert-annotated lumen areas. The proposed algorithm allows for rapid, accurate, and automated detection of polymeric struts and the luminal border in OCT images.

Automated Segmentation of Bioresorbable Vascular Scaffold Struts in Intracoronary Optical Coherence Tomography Images.

Bioresorbable vascular scaffolds (BVS), the next step in the continuum of minimally invasive vascular interventions present new opportunities for patients and clinicians but challenges as well. As they are comprised of polymeric materials standard imaging is challenging. This is especially problematic as modalities like optical coherence tomography (OCT) become more prevalent in cardiology. OCT, a light-based intracoronary imaging technique, provides cross-sectional images of plaque and luminal morphology. Until recently segmentation of OCT images for BVS struts was performed manually by experts. However, this process is time consuming and not tractable for large amounts of patient data. Several automated methods exist to segment metallic stents, which do not apply to the newer BVS. Given this current limitation coupled with the emerging popularity of the BVS technology, it is crucial to develop an automated methodology to segment BVS struts in OCT images. The objective of this paper is to develop a novel BVS strut detection method in intracoronary OCT images. First, we preprocess the image to remove imaging artifacts. Then, we use a K-means clustering algorithm to automatically segment the image. Finally, we isolate the stent struts from the rest of the image. The accuracy of the proposed method was evaluated using expert estimations on 658 annotated images acquired from 7 patients at the time of coronary arterial interventions. Our proposed methodology has a positive predictive value of 0.93, a Pearson Correlation coefficient of 0.94, and a F1 score of 0.92. The proposed methodology allows for rapid, accurate, and fully automated segmentation of BVS struts in OCT images.

Use of Systemic Vasodilators for the Management of Doppler Ultrasound Arterial Abnormalities After Orthotopic Liver Transplantation

Doppler ultrasound (DUS) arterial abnormalities (DAA) after orthotopic liver transplantation (OLT) often represent a sign of hepatic artery (HA) complication (HAC). The standard management of DAA involves computed tomographic angiography (CTA) followed by invasive vascular intervention (IVI) or observation. We evaluated the contribution of systemic vasodilators (SVD) to the management of DAA after OLT. Between 2005 and 2015, 91 of 514 OLT recipients developed DAA (defined by HA resistive index [HARI] <0.5) and received oral SVDs. Doppler ultrasound was performed 2 days later, and patients were assigned to 3 groups accordingly: the normalization group (HARI >0.5), improvement group (HARI increase of >0.1 but value <0.5), or nonresponse group. We analyzed the contribution of this strategy to predict clinically significant HAC, defined as thrombosis or HAC requiring IVI. A clinically significant HAC (4 thromboses, 35 HACs requiring IVI) was found in 2.9% (n = 1/34), 32.1% (n = 9/28), and 100% (n = 29/29) of patients in the normalization, improvement, and nonresponse groups, respectively (P < 0.001). On multivariate analysis, absence of HARI normalization after SVD and time to DAA longer than 30 days were associated with clinically significant HAC. Specificity and accuracy of DUS after SVD increased from 88.1% to 95.1% and from 88.9% to 95.1% (P < 0.001), without altering its sensitivity (97.7% vs 95.5%, P = 1.000). The use of SVD improves the diagnostic performance of DUS for clinically significant HAC after OLT. It allows identifying patients at low risk for HAC, for whom CTA could be avoided, and helps choosing between observation and IVI in patients with inconclusive CTA.

Simulator for Minimally Invasive Vascular Interventions: Hardware and Software

In the present work, a simulation system is proposed that can be used as an educational tool by physicians in training basic skills of minimally invasive vascular interventions. In order to accomplish this objective, initially the physical model of the wire proposed by Konings has been improved. As a result, a simpler and more stable method was obtained to calculate the equilibrium configuration of the wire. In addition, a geometrical method is developed to perform relaxations. It is particularly useful when the wire is hindered in the physical method because of the boundary conditions. Then a recipe is given to merge the physical and the geometrical methods, resulting in efficient relaxations. Moreover, tests have shown that the shape of the virtual wire agrees with the experiment. The proposed algorithm allows real-time executions, and furthermore, the hardware to assemble the simulator has a low cost.

A novel approach for a 2D/3D image registration routine for medical tool navigation in minimally invasive vascular interventions

Minimally invasive interventions are frequently aided by 2D projective image guidance. To facilitate the navigation of medical tools within the patient, information from preoperative 3D images can supplement interventional data. This work describes a novel approach to perform a 3D CT data registration to a single interventional native fluoroscopic frame. The goal of this procedure is to recover and visualize a current 2D interventional tool position in its corresponding 3D dataset.A dedicated routine was developed and tested on a phantom. The 3D position of a guidewire inserted into the phantom could successfully be reconstructed for varying 2D image acquisition geometries. The scope of the routine includes projecting the CT data into the plane of the fluoroscopy. A subsequent registration of the real and virtual projections is performed with an accuracy within the range of 1.16±0.17mm for fixed landmarks. The interventional tool is extracted from the fluoroscopy and matched to the corresponding part of the projected and transformed arterial vasculature. A root mean square error of up to 0.56mm for matched point pairs is reached. The desired 3D view is provided by backprojecting the matched guidewire through the CT array.Due to its potential to reduce patient dose and treatment times, the proposed routine has the capability of reducing patient stress at lower overall treatment costs.

İnvaziv Vasküler Girişim Sonrası Akut Böbrek Yetmezliği Gelişen Bir Olgu: Kontrast Nefropatisi mi? Kolesterol Emboli Sendromu mu? Birliktelik mi?

Even though radiocontrast nephropathy is usually the most common cause of acute renal failure (ARF) following invasive vascular interventions, cholesterol embolism should be considered in the differential diagnosis. It is very important to differentiate these 2 conditions because of the disparities between treatment modalities and renal–patient survivals. To discuss possible causes and the differential diagnosis, we present a case that developed ARF following an endovascular aortic reconstruction (EVAR) operation for a thrombosed abdominal aorta aneurysm. key words: Contrast nephropathy, Cholesterol embolism, Acute renal failure, Angiography

Acute coronary syndrome in Behcet's disease caused by a coronary artery aneurysm and thrombosis

Behcet's disease (BD) is a multisystemic vasculitis that can involve vessels of all sizes and is characterized by recurrent oral and genital ulcers with variable manifestations affecting the skin, eyes, and central nervous and musculoskeletal systems. Vascular involvement in BD is reported to be up to 40% in different series. The abdominal and thoracic aorta and pulmonary and femoral arteries are the most commonly involved arteries. However coronary arteries are rarely affected. Herein, we present a 29-year-old man who was consulted with progressive severe chest pain of 3 days in duration to our clinic. The patient was diagnosed with BD with mucocutaneous symptoms and a positive pathergy test 1 year ago and was in clinical remission for the last 6 months. At the first evaluation in the emergency department, the patient's vital signs were stable, whereas he had elevated troponin T levels with a normal electrocardiogram and hypokinetic areas in the apex of the heart in the echocardiography. Conventional and computed tomography coronary angiography revealed aneurysms and intramural thrombosis in the left anterior descending and right coronary arteries. Although ischemic symptoms and signs improved with anticoagulant and antiaggregant therapies, coronary aneurysms were observed to increase in size. Immunosuppressive (IS) treatment was started with pulse intravenous corticosteroids and cyclophosphamide. Because of the high re-stenosis risk, stents were not applied to the affected vessels during the acute thrombosis period. During routine investigations, an in situ pulmonary thrombosis was also detected bilaterally in the peripheral pulmonary arteries. In conclusion, coronary artery aneurysm is a rare and poor prognostic manifestation of BD. The treatment protocol for these aneurysms is not well clarified. IS therapies are definitely indicated, but the role of anticoagulants and invasive vascular interventions is controversial.

Removal of a missed guide wire in central vein with endovascular intervention: a case report

Cardiovascular Surgery and Interventions publishes original articles on topics in cardiovascular surgery, cardiovascular anesthesia and cardiology. These encompass all relevant clinical, surgical and laboratory studies, editorials, current and collective reviews, technical know-how papers, case reports, interesting images, “How to Do It” papers, correspondence and commentary.

Perioperative management of diabetic foot.

Perioperative management of diabetic foot.

Age-related Vascular Differences among Patients Suffering from Multiple Sclerosis

The aim of our study was to analyze morphological and functional aspects of cerebral veins by means of ecocolor-Doppler in young (i.e., ≤ 30 years old) and older (i.e., >30 years old) patients suffering from multiple sclerosis. 552 multiple sclerosis patients were evaluated by means of a dedicated Echo-Color-Doppler support (MyLab Vinco echocolor Doppler System, Esaote), in both supine and sitting positions. 458 (83%) showed alterations in their morphological and functional structures of cerebral veins and were divided in two different groups: 1) ≤ 30 (110 patients) and 2) >30 years old (348 patients). Young patients showed a statistically significant higher number of both hemodynamically (44% vs. 35%, p<0.01) and non-hemodynamically (51% vs. 45%, p<0.05) significant stenosis in the internal jugular veins as compared to older patients. A lower percentage of young patients showed blocked outflow in the cervical veins (50% vs. 65%, p<0.01) as compared to older ones. Patients >30 years old outlined a significantly higher disability degree (Expanded Disability Status Scale score: 5 vs. 3, p<0.01) as well as higher disease duration (12 vs. 5 months, p<0.01) than younger. No differences could be outlined about multiple sclerosis clinical form of the disease. It was evidenced that young and adult groups are different kind of patients, the former showing much more cerebral veins stenosis and blocked flow in internal jugular veins and vertebral veins than the latter. Duration of disease could explain such differences: the higher the diseases duration, the higher the degree of vascular alterations and, therefore, the disability degree. This could be due to the complex venous hemodynamic impairments induced by alterations in vascular walls: the blocked or difficult blood flow through stenosis could increase the hydrostatic pressure in the skull and this could induce damages to cerebral cells leading to the genesis of more advanced morphological abnormalities. Furthermore, the vessels' alterations could impair venous endothelial functions which could turn in a possible alteration of the controls of cerebral vein return which could worsen the cerebral vascular outflow. It may be possible that early clinical, pharmacological and/or invasive vascular interventions could exert a possible role in the natural history of multiple sclerosis. Nevertheless, further trials are needed in order to confirm such considerations.

Performance optimization of force feedback control system in virtual vascular intervention surgery.

In virtual surgery of minimally invasive vascular intervention, the force feedback is transmitted through the flexible guide wire. The disturbance caused by the flexible deformation would affect the fidelity of the VR (virtual reality) training. SMC (sliding mode control) strategy with delayed-output observer is adopted to suppress the effect of flexible deformation. In this study, the control performance of the strategy is assessed when the length of guide wire between actuator and the operating point changes. The performance assessment results demonstrate the effectiveness of the proposed method and find the optimal length of guide wire for the force feedback control.

Outcome of Ischemic Foot Ulcer in Diabetic Patients Who Had no Invasive Vascular Intervention

There is limited information regarding outcome in patients not available for revascularisation. Our aim was to identify factors related to ulcer healing in diabetic patients with severe peripheral arterial disease who were not available for revascularisation. Diabetic patients with a foot ulcer, consecutively presenting at a multidisciplinary foot centre with systolic toe pressure <45 mmHg or an ankle pressure <80 mmHg were prospectively included. Patients who received revascularisation were excluded. All patients had continuous follow-up until healing or death. Out of 602 patients (median age: 76 years) included in this study, 50% healed either primarily (76%) or with a minor amputation (24%). Seventeen percent of patients healed after major amputation and 33% died unhealed. By regression analysis, rest pain, impaired renal function, ischemic heart disease, cerebral vascular disease, extent of tissue destruction, and ankle pressure >50 mmHg affected the outcome of the ulcers. Diabetic patients with ischemic foot ulcers not available for revascularisations are not excluded from healing without major amputation. Factors strongly related to outcome were co-morbidity, severity of peripheral arterial disease, and extent of tissue destruction. Our findings reinforce the need for a classification system considering these factors at decision-making for vascular intervention.

Multidisciplinary treatment for peripheral arterial occlusive disease and the role of eHealth and mHealth

Increasingly unaffordable health care costs are forcing care providers to develop economically viable and efficient health care plans. Currently, only a minority of all newly diagnosed peripheral arterial occlusive disease (PAOD) patients receive efficient and structured conservative treatment for their disease. The aim of this article is to introduce an innovative effective treatment model termed ClaudicatioNet. This concept was launched in The Netherlands as a means to combat treatment shortcomings and stimulate cohesion and collaboration between stakeholders. The overall goal of ClaudicatioNet is to stimulate quality and transparency of PAOD treatment by optimizing multidisciplinary health care chains on a national level. Improved quality is based on stimulating both a theoretical and practical knowledge base, while eHealth and mHealth technologies are used to create clear insights of provided care to enhance quality control management, in addition these technologies can be used to increase patient empowerment, thereby increasing efficacy of PAOD treatment. This online community consists of a web portal with public and personal information supplemented with a mobile application. By connecting to these tools, a social community is created where patients can meet and keep in touch with fellow patients, while useful information for supervising health care professionals is provided. The ClaudicatioNet concept will likely create more efficient and cost-effective PAOD treatment by improving the quality of supervised training programs, extending possibilities and stimulating patient empowerment by using eHealth and mHealth solutions. A free market principle is introduced by introducing transparency to provided care by using objective and subjective outcome parameters. Cost-effectiveness can be achieved using supervised training programs, which may substitute for or postpone expensive invasive vascular interventions.

Establishing an individual dosing system for patients undergoing interventional transcatheter arterial embolization: Radiochromic film and Monte Carlo simulation

Less invasive imaging-guided vascular interventions with fluoroscopy and digital subtraction angiography have recently become widespread and have been successfully used for treating various diseases. However, interventional fluoroscopy procedures may present deterministic and stochastic radiation risks. The International Commission on Radiological Protection (ICRP) and the Food and Drug Administration have requested identifying procedures that may involve patient doses greater than the recommended thresholds. In this study, radiochromic dosimetric media, known as self-developing films, and measurement-based Monte Carlo simulations were used to establish an interventional radiology dosing system for individual patients undergoing interventional transcatheter arterial embolization. The peak skin dose, evaluated from the entrance surface dose distribution, was 21% less than the cumulated dose reported from the console. A 3D dose map incorporated into CT images was established. The organ doses and effective doses for individual patients were evaluated using this dosing system. This system could be applied very well to other fluoroscopic or interventional procedures for patient dose management.

A realistic elastic rod model for real-time simulation of minimally invasive vascular interventions

Simulating intrinsic deformation behaviors of guidewire and catheters for interventional radiology (IR) procedures, such as minimally invasive vascular interventions is a challenging task. Especially real-time simulations for interactive training systems require not only the accuracy of guidewire manipulations, but also the efficiency of computations. The insertion of guidewires and catheters is an essential task for IR procedures and the success of these procedures depends on the accurate navigation of guidewires in complex 3D blood vessel structures to a clinical target, whilst avoiding complications or mistakes of damaging vital tissues and blood vessel walls. In this paper, a novel elastic model for modeling guidewires is presented and evaluated. Our interactive guidewire simulator models the medical instrument as thin flexible elastic rods with arbitrary cross sections, treating the centerline as dynamic and the deformation as quasi-static. Constraints are used to enforce inextensibility of guidewires, providing an efficient computation for bending and twisting modes of the physically-based simulation model. We demonstrate the effectiveness of the new model with a number of simulation examples.