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Background: Pulmonary vein (PV) isolation using a balloon-mounted cryoablation system is a new technology for the percutaneous treatment of atrial fibrillation (AF). Transesophageal echocardiography (TEE) allows real-time visualization of cryoballoon positioning and successful vein occlusion via color Doppler. We hypothesized that PV mechanical occlusion monitored with TEE could predict effective electrical isolation., Methods: We studied 124 PVs in 30 patients. Under continuous TEE assessment, a cryoballoon was placed in the antrum of each PV aiming for complete PV occlusion as documented by color Doppler. At the end of the procedure, PV electrical isolation was evaluated using a circumferential mapping catheter., Results: Of the 124 PVs studied, 123 (99.2%) could be visualized by TEE: the antrum was completely visualized in 80 of them (64.5%), partially in 36 (29.0%), and only disappearance of proximal flow could be observed in the remaining 7 PVs (5.7%). Vein occlusion could be achieved in 111 of the 123 (90.2%) visualized PVs. Postinterventional mapping demonstrated electrical isolation in 109 of 111 occluded PVs (positive predictive value 98.2%) and only in 1 of 12 nonoccluded PVs (negative predictive value 91.7%, P < 0.001). After a mean follow-up of 7.4 +/- 3.7 months, 73.3% of patients remained in sinus rhythm without antiarrhythmic drugs., Conclusion: Color Doppler documented PV occlusion during cryoballoon ablation can predict effective electrical isolation.

Introduction: Cryoballoon (CB) ablation represents a novel technology for pulmonary vein isolation (PVI). We investigated feasibility and safety of CB-PVI, utilizing a novel spiral catheter (SC), thereby obtaining real-time PV potential registration., Methods: Following double transseptal puncture, a Lasso catheter (Biosense Webster, Diamond Bar, CA, USA) and the 28 mm CB were positioned within the left atrium. A novel SC (Promap, ProRhythm Inc., Ronkonkoma, NY, USA) was inserted through the lumen of the CB allowing PV signal registration during treatment. Time to PV conduction block was analyzed. If no stable balloon position was obtained, the SC was exchanged for a regular guide wire and PV conduction was assessed after treatment by Lasso catheter., Results: In 18 patients, 39 of 72 PVs (54%) were successfully isolated using the SC. The remaining 33 PVs were isolated switching to the regular guide wire. Time to PV conduction block was significantly shorter in PVs in which sustained PVI was achieved as compared to PVs in which PV conduction recovered within 30 minutes (33 +/- 21 seconds vs 99 +/- 65 seconds). In 40 PVs, time to PV conduction block was not obtained because of: (1) PVI not being achieved during initial treatment; (2) a distal position of the SC; or (3) isolation with regular guide wire. No procedural complications occurred., Conclusion: Visualization of real-time PV conduction during CB PVI is safe, feasible, and allows accurate timing of PVI onset in a subset of PVs. Time to PV conduction block predicts sustained PVI. However, mechanical properties of the SC need to be improved to further simplify CB PVI.

Despite the impressive progress of percutaneous treatment modalities, restenosis remains the major Achilles heel of interventional cardiology. Approximately 25% of the general population treated for coronary diseases with a bare-metal stent and about 10% of patients treated with a drug-eluting stent develop an overgrowth of vascular tissue and renarrowing inside the stent, or in-stent restenosis. These rates are even greater in diabetics and patients at higher risk of restenosis both for clinical presentation (patients in dialysis, low ejection fraction) or anatomical characteristics (ostial, bifurcation, long lesions). Non-stent based local drug delivery and particularly the use of paclitaxel eluting balloon (PEB) could be one promising strategy to reduce restenosis. This review will briefly explore the different characteristics of PEB devices currently present in the market and summarize the results obtained both in animal models and clinical practice, giving an indication of the potential field of application of this new technology.

Despite aggressive efforts to increase autogenous fistula prevalence primarily from recommendations by the NKF and the Fistula First National Vascular Access Improvement Initiative, catheters remain an essential access modality for a large percentage of the hemodialysis population. Tunneled dialysis catheters or chronic catheters are associated with a multitude of complications including infections, stenosis, thrombosis, and increased morbidity and mortality even after adjustment for potential confounding variables. Also, given the blood flow rates of catheters, dialysis adequacy is compromised as compared with arteriovenous fistulae and arteriovenous grafts. This review endeavors to provide an update on catheter outcomes in the Fistula First and Kidney Disease Outcomes Quality Initiative era in relation to the increasing fistula prevalence and decline in graft placements. The conflicting view of whether catheters are increasing concurrently with the increase in fistula prevalence is discussed. The management of tunneled dialysis catheter-related complications is considered with a review of the most recent data. Future research strategies and innovations in catheter design are also addressed. This review provides a comprehensive update of tunneled hemodialysis catheters, their necessity and pitfalls, and novel directions for future investigation.

We present data concerning the extraction of clots using the newly invented "GP" mechanical thrombectomy device (MTD). Artificial and porcine clots of various lengths were used in plastic tube models of an artery. We investigate the pressures and times taken for clot extraction together with the volumes of fluid extracted. We also investigate the impact of using a funnel structure mounted on the end of the device, on clot removal times and fluid removed. Finally, we present results involving clot extraction from the posterior popliteal artery of a cadaver. Our data indicated that: The embedded GP MTD is the most effective device regarding artificial and porcine blood clot removal. This result is consistent with previous published data on this device. The GP MTD was effective in removing clots positioned in the posterior popliteal artery of a cadaver. The embedded GP device removes less fluid compared with the end-mounted GP device. This confirms previous studies. There appears to be a relationship between funnel angle and pressure. Lower extraction pressures are required for larger funnel angles mounted on the GP device. Shorter times of clot extraction are required for larger funnel angles.

Interventional paediatric and congenital cardiology is expanding at a rapid pace. Validated techniques (such as aortic or pulmonary valve dilatations and occlusion of persistent ductus arteriosus and atrial septal defects) are improving thanks to the use of smaller introducers and sheaths, low-profile balloons and novel devices. Moreover, catheter-based interventions have emerged as an attractive alternative to surgery in other fields: pulmonary valve replacement, balloon and stent implantation for native and recurrent coarctation, and percutaneous closure of ventricular septal defects. On the other hand, percutaneous interventions in the paediatric population may be limited by patient size or the anatomy of the defect. Hybrid approaches involving both cardiac interventionists and surgeons are being developed to overcome these limitations. Based on a better understanding of cardiac development, fetal cardiac interventions are being attempted in order to alter the history of severe obstructive lesions. Finally, some interventional procedures still carry a low success rate-for example, pulmonary vein stenosis, even with the use of conventional stents. Biodegradable stents and devices are being developed and may find an application in this setting as well as in others. The purpose of this review is to highlight the advances in paediatric interventional cardiology since the beginning of the third millennium.

Double-balloon endoscopy (DBE) was developed as a new technique for visualization of and intervention in the entire small intestine. In DBE, the intestinal walls are held apart by a balloon attached to the distal end of a soft overtube. DBE has been reported worldwide to be very useful for not only diagnosis but also endoscopic therapy. Biopsy samples of small intestinal tumors can be obtained using DBE, and the appropriate treatment can be selected before a surgical procedure. For inflammatory diseases, DBE can reveal the localization of ulcers in the lumen (on the mesenteric or antimesenteric side), which is important for differential diagnosis. Some endoscopic therapies such as hemostatic procedures, polypectomy, and dilation therapy for benign strictures can be performed in the same manner as in the large intestine. DBE may also be suitable for colonoscopy for difficult insertion cases and therapeutic procedures such as endoscopic submucosal dissection. Furthermore, a double-balloon endoscope can be selectively inserted into the afferent loop to perform endoscopic retrograde cholangiopancreatography in patients with Roux-en-Y anastomosis, allowing various kinds of endoscopic treatments for biliary diseases to be successfully performed. Endoscopic therapy in the small intestine, whose wall is very thin, should be performed with special care to avoid complications such as bleeding and perforation. In the future, improvement is expected in terms of maneuverability, therapeutic capability, and imaging technology such as the addition of a magnifying function and flexible spectral imaging color enhancement. We anticipate that DBE will contribute to the establishment of medical science of the small intestine and to research elucidating the mechanisms of small intestinal diseases.

Very large and giant (> or =15 mm) cerebral aneurysms have a poor natural history, with high risk of subarachnoid hemorrhage or progressive symptoms of mass effect. Several endovascular techniques may be applied for treatment, depending on location, size, anatomy and presence of collateral circulation. The authors reviewed their clinical experience in endovascular treatment of 232 very large and giant aneurysms and present their perspective on the present state of the art in endovascular therapy for these aneurysms.

Introduction: Introduction In an attempt to reduce unnecessary central venous catheters (CVC) dependence in prevalent population, a "CVC removal" programme was initiated in our unit. The objective was to diminish the number of CVC and to analyze the causes of their insertion and maintenance. On 09/01/07, 38 out of 173 prevalent patients on hemodialysis. Methods were CVC dependant (21.9%): 16 incident patients (42,1%) and 22 (57,8%) prevalent patients. All of them were re-evaluated for permanent vascular access utilization, included those previously rejected for surgery. Physical, psychical and vascular aspects regarding each patient were taken into consideration. The following variables were age, Body mass index, time on hemodialysis, Charlson analyzed comorbidity index, DM or vascular comorbidities and number of vascular accesses created prior to CVC placement. In those patients in whom AVF creation was feasible, the following were registered after 18 months of 1.Primary failure rate. 2. Related complications. 3. up follow Percentage of usable AVF or AVG. 4. Percentage of removed CVC. 5. Mortality and hospitalization. The decision of no realization of a new vascular access and? Results maintenance of TVC was performed in 21 patients (55.2%). In 9 of them was decision of the nephrologists and the family. In 11 patients was decision of vascular surgeon due to vascular bed exhaustion. A permanent VA was achieved in 17 patients (44.7%), 50% of them was incident patients and 45% prevalent patients. The primary failure rate was 0%. The TVC was withdrawn in 11/17 (64.7%). Only 4 patients remain without TVC after 18 months of follow-up: 5 patients died (4 with a AVF functioning and 1 VA closure due to steal syndrome) and in 8 patients was mandatory to reintroduce the TVC again. Immediate complications after the surgery were: 1 severe haematoma, 2 infections and 2 severe sequestrations. 3 patients required hospital admission following complications directly related to VA. Mean time of free of TVC was 5.2 months (range: 0.7- 14.3 months). The mortality was 29,4% (5/17) in the group of patients with a new VA and 9,5% (2/21) in the other group(RR 3,19; IC 95%: 0,68-13,98; p: 0,11). No significant differences were observed between patients who transitioned to a permanent vascular access and those who remained TVC dependant in regards to age, gender, BMI, time on dialysis, DM, comorbidity or number of previous VA, Transition from CVC use to hospitalizations or mortality. Conclusions permanent vascular access is possible in prevalent patients in dialysis. Improvement was achieved by a modest amount, and after a prolonged process with gravel complications, some of which proved severe. Need for CVC dependence is confirmed in a high percentage of prevalent patients on dialysis. Comorbidity might have influenced the results. The quality standard should be adequate to reality of current population on hemodialysis.

Catheter ablation has become the curative treatment modality for various arrhythmias. Extending the indications for catheter ablation from simple supraventricular tachycardias to complex arrhythmias such as ventricular tachycardia or atrial fibrillation, the investigator faces prolonged procedure times, fluoroscopy exposure and the need for stable and reproducible catheter movement. Recently, remote-controlled robotic catheter ablation has emerged as a novel ablation concept to meet these requirements. This review describes the two available robotic ablation systems and summarizes their clinical applications and current human experience.

Background: Radiofrequency neurolysis is a common technique used in the treatment of chronic pain, particularly facet (zygapophyseal joint) arthralgia. A needle-like cannula is insulated except for the exposed active tip, which is positioned as parallel and adjacent as possible to the targeted nerve branch. Via an inserted probe connected to a radiofrequency generator, energy flowing from the tip of the cannula creates a heat lesion in the 80 - 85 degree Celsius range mostly about the length of the exposed active tip and in proportion to the diameter of the probe. The common active tip lengths used for neurolysis are 5mm or 10mm. The cannulae are FDA approved. The manufacturer advises physicians not to bend or otherwise modify a cannula prior to use. The cannulae are available straight or bent, sharp and blunt. The technique is guided under C-arm fluoroscopy. X-rays passing through the patient demonstrate in 2 dimensions the projected relative radio-opaque bony landmarks and the metallic cannula. Most currently available cannulae are uniform in their radio-opacity from tip to hub. The physician must make an educated guess as to the portion of the cannula that will be making the lesion in relationship to the bony landmark., Objective: A new radiofrequency cannula with a radio-opaque marker (ROC) delineates the proximal end of the active tip. The cannula was used in a phantom model. Images were reproduced with explanation of the potential advantage of the new device., Result: The marker on the new cannula was visible and did help delineate the active tip as well as its orientation. It was also helpful in making sequential lesions at the same nerve using a "tip to tail" repositioning technique., Conclusion: The ROC did represent an improvement over standard cannulae to optimize visualization of cannula and thus lesion placement using a phantom model. The applications described were only for conventional or "hot" RF.

Silicone is the material of choice for many new applications. Those examined here include drug delivery and peristaltic pumps, pacemaker leads and tubing used in minimally invasive surgery and to deliver high pressure gases and liquids.

Acute ischemic stroke is a major cause of morbidity and mortality in industrialized nations. The sequel of stroke ranges from mild to severe disability and even death. Since the impairment may be permanent, the costs to society from work incapacity and the need for long-term care can be high. Additionally, the burden of suffering associated with the disease may have devastating effects on individuals and families. Following the occlusion of a cerebral vessel, the full extent of the infarction may not become clinically and radiologically apparent until days after. By then, the surrounding watershed zone, or penumbra, either survives or succumbs to necrosis over time. The natural history of this "tissue at risk" is determined by two factors: the collateralization from other vascular territories and the possible occurrence of spontaneous recanalization of the occluded vessel. The current treatment options for acute ischemic stroke are aiming at an early and sustained restoration of flow to the penumbra. The effect of the treatment is therefore time-dependent and the neurologic outcome is a function of the time span between onset of symptoms and recanalization therapy as well as of the recanalization rate associated with a specific treatment. This report summarizes the results of the major trials on catheter-based interventions, either using thrombolytic drugs or novel mechanical approaches being developed to treat patients with acute ischemic stroke.

Objective: We describe our initial experience with the use of a novel, compliant guide catheter designed for placement within the cranial vasculature in a series of seven patients who were treated for various intracranial pathologies., Clinical Presentation: Seven patients were deemed to have either tortuous supra-aortic, intracranial, and/or extracranial vasculature or to require additional microcatheter support as the result of lesion location., Intervention: The patients were treated, in part, with the 6-French Neuron delivery catheter (Penumbra, Inc., San Leandro, CA) at the authors' two institutions. The guide catheter was positioned in various distal locations within the intracranial internal carotid artery or external carotid artery. Three patients were treated for unruptured intracranial aneurysms, 2 patients for intracranial atherosclerosis, 1 patient for an arteriovenous malformation, and 1 patient for a pseudoaneurysm., Conclusion: All lesions were successfully treated through a microcatheter advanced in a coaxial fashion through the guide catheter. There were no complications related to the positioning of the catheter. Distal intra- or extracranial placement of a specially designed, compliant guide catheter can be performed safely and may improve access and microcatheter stability in patients with tortuous vessels or difficult-to-reach lesions.

September 2007 marked the 30-year anniversary of the first human percutaneous coronary intervention, an index event that changed the course of modern-day cardiovascular care. Before that first procedure, adult invasive cardiology focused on diagnostic angiography as well as hemodynamic assessment of structural heart disease. Since that initial procedure, percutaneous coronary intervention has become the most frequently performed coronary revascularization procedure worldwide. Several factors have been responsible for this dramatic paradigm shift, the most prominent being identification of opportunities for technical improvement and the application of innovation and investigation in concert with colleagues, professional societies, and industry. These approaches will continue to be of paramount importance as new technologies are brought to bear on an increasingly broader group of patients with cardiovascular disease.

The present study describes modifications to the endovascular filament model of subarachnoid hemorrhage (SAH) in rats. Specifically, we sought to improve the percentage yield of SAH, reduce mortality rates and better simulate human cerebral aneurysmal rupture. Instead of using a 4-0 prolene suture to induce SAH in the existing endovascular filament model, a hollow and flexible polyetrafluoroethylene (PTFE) tube was maneuvered into the proximal anterior cerebral artery (ACA) to ensure that advancement occurred without producing trauma to the vessels. SAH was induced by advancing a tungsten wire through this tube, perforating the ACA at the desired location. These modifications produced significant improvements over the endovascular filament model. Mortality rate declined from 46 to 19%, and SAH was produced more frequently. With the prolene suture, only 48% of our attempts produced a SAH, and unsuccessful attempts typically resulted in an acute subdural hematoma (ASDH). In contrast, the wire/tubing technique was 90% successful at inducing SAH, and led to a significant reduction of ASDH incidence from 44 to 6%. Additionally, the modified technique produced vasospasm in basilar and middle cerebral arteries post-SAH as well as pseudoaneurysms in the proximal ACA which indicated the location of vessel perforation.

Background: Aortic valvuloplasty (AoVP) is an established procedure regarded as a valid alternative for surgical management of congenital aortic valve stenosis. However, its long-term efficacy in preventing or postponing aortic valve surgery remains uncertain for the individual patient. Therefore, the aim of this study was to study the long-term results of AoVP in pediatric patients and its efficacy in preventing or postponing aortic valve surgery., Methods and Results: We reviewed up to 17.5 years of follow-up data of all 188 patients who received AoVP at the Deutsches Herzzentrum München. The patients were divided into those < 1 month of age (group < 1 month; n=68) and those > or = 1 month of age (group > or = 1 month; n=120) at the time of AoVP. After the first and second AoVP, moderate and severe aortic regurgitation developed in 29% and 14%, respectively, of the patients in group < 1 month and in 19% and 29%, respectively, of the patients in group > or = 1 month. Survival after 10 years free from aortic valve surgery was 59% (95% confidence interval, 45 to 73) in group < 1 month and 70% (95% confidence interval, 59 to 81) in group > or = 1 month., Conclusions: This study shows that the long-term results of AoVP of congenital aortic valve stenosis in pediatric patients and its efficacy in preventing or postponing aortic valve surgery are very good. About two thirds of the patients are free from aortic valve surgery 10 years after AoVP.

Catheter-associated urinary tract infections (CAUTIs) represent the most common type of nosocomial infection and are a major health concern due to the complications and frequent recurrence. These infections are often caused by Escherichia coli and Proteus mirabilis. Gram-negative bacterial species that cause CAUTIs express a number of virulence factors associated with adhesion, motility, biofilm formation, immunoavoidance, and nutrient acquisition as well as factors that cause damage to the host. These infections can be reduced by limiting catheter usage and ensuring that health care professionals correctly use closed-system Foley catheters. A number of novel approaches such as condom and suprapubic catheters, intermittent catheterization, new surfaces, catheters with antimicrobial agents, and probiotics have thus far met with limited success. While the diagnosis of symptomatic versus asymptomatic CAUTIs may be a contentious issue, it is generally agreed that once a catheterized patient is believed to have a symptomatic urinary tract infection, the catheter is removed if possible due to the high rate of relapse. Research focusing on the pathogenesis of CAUTIs will lead to a better understanding of the disease process and will subsequently lead to the development of new diagnosis, prevention, and treatment options.

Aortic balloon valvuloplasty (BAV) was initially devised in the 1980s as an alternative procedure to the surgical treatment of aortic stenosis, with the theory behind it being both minimally invasive as well as having a lower complication rate [Hara H, et al. Percutaneous balloon aortic valvuloplasty revisited: time for a renaissance? Circulation 2007 March;115(12):e334-8]. In practice however, the procedure was found to have a higher complication rate with only a modest haemodynamic improvement compared to the surgical approach. Most important of all it had an unacceptably high restenosis rate as a substitute for surgery [Otto CM, et al. 3-year outcome after balloon aortic balloon valvuloplasty: insights into prognosis of valvular aortic stenosis. Circulation 1994;89:642-50]. As a result, the procedure has fallen out of favour and has been abandoned at many health care facilities [Hara H, et al. Percutaneous balloon aortic valvuloplasty revisited: time for a renaissance? Circulation 2007 March;115(12):e334-8]. This article will review the management of patients with severe aortic stenosis that are unsuitable to undergo surgery.

Background: The persistence of significant tricuspid regurgitation (TR) after percutaneous mitral valvuloplasty (PMV) is known to be an independent predictor of adverse outcome in mitral stenosis (MS). However, it remains unclear whether mitral valve (MV) surgery combined with surgical correction of TR is the better treatment option than PMV in patients with severe MS and severe functional TR., Methods and Results: We included a total of 92 consecutive patients (18 men, age 49+/-13 years) with severe MS and severe functional TR, who were potential candidates for PMV from 1997 to 2005, and the exclusion criteria were defined as the presence of left atrial thrombi, mitral regurgitation > or = grade 3, echo score > 10, and left ventricular ejection fraction (EF) < 35%. PMV was performed on 48 patients (PMV group), and MV surgery combined with tricuspid valve (TV) repair was performed on 44 patients (TVP group). The clinical events were defined as death, repeat surgical or percutaneous intervention, and readmission because of heart failure. There were no significant differences between the 2 groups in terms of gender, baseline EF, and baseline severity of pulmonary hypertension, but patients in the TVP group were older and had a higher echo score and a higher incidence of atrial fibrillation than those in the PMV group. During follow-up of 57+/-35 months, 2 deaths occurred in the TVP group, and there were 2 deaths, 7 cases of heart failure requiring surgical intervention in the PMV group. The difference of event rates between the 2 groups showed borderline significance (P=0.05), but no difference in mortality was observed. The estimated actuarial 7-year event-free survival rate was 77+/-8% in the PMV group and 95+/-3% in the TVP group. Severe TR was improved to mild or absent TR in 43 (98%) patients in the TVP group, and this was significantly higher than in the PMV group (22/48, 46%; P<0.001). In the TVP group, the right ventricle (RV) size was significantly decreased in 18 (90%) patients among 20 patients with preoperative significant RV enlargement. On stepwise multivariate logistic regression analysis, TVP group and baseline sinus rhythm were independent predictors for improvement of TR (P<0.001)., Conclusions: TV repair combined with MV surgery was related to better clinical outcomes than PMV alone, and we recommend that this surgical option should be considered preferentially in severe MS with severe functional TR, especially if atrial fibrillation or enlarged RV is associated.

In recent years, there have been some interesting advances in the science and practice of peritoneal dialysis (PD). This review focuses on selected technological advances and the impact that these changes may have on this modality. New, so-called "biocompatible" fluids have more physiologic pH and reduced glucose degradation products. These new fluids may reduce the deleterious effects of chronic exposure to the peritoneal membrane. However, enthusiasm for these new fluids is outstripping rigorous evidence that they change patient outcome. Continuous-flow PD offers a way to increase dramatically small solute clearance. However, there are significant technological barriers to the implementation of this kind of dialysis. Furthermore, there is little evidence that augmented small solute clearance will improve survival in PD patients. Finally, new catheter insertion techniques provide perhaps the most practical advances in allowing successful commencement of this excellent home dialysis modality.

Background: The adjunctive use of interventional radiology procedures to minimize and control bleeding at the time of cesarean delivery has become increasingly common. These procedures require modern imaging equipment and supplies not available in traditional operating rooms., Methods: We describe three women who strongly desired continued reproductive function in clinical circumstances where postpartum hemorrhage and hysterectomy were likely., Results: Cesarean delivery was performed in the interventional radiology suite after selective uterine artery balloon placement and/or embolotherapy, which successfully minimized blood loss during delivery., Conclusion: We propose that this novel surgical location is feasible, and may offer advantages in select patients.

Background and Purpose: Brain aneurysms and vascular malformations can cause cerebral hemorrhages, with devastating consequences for the patients and their families. Since the development of microcatheters and materials used for endovascular embolization, we have witnessed a rapid advancement in the technology and in the number or patients treated with this approach. The aim of this review is to survey recent data relevant to new technologies and emerging treatment strategies in these areas., Summary of Review: Clinical trials assessing the safety and efficacy of coil embolization for cerebral aneurysms were based on the use of bare platinum, helical coils. Since then, endovascular operators have been testing and using new materials such as bioactive coils, expandable coils, and complex-shaped coils. Based on the data so far obtained, third and fourth generation coil designs are rapidly emerging and will be ready for clinical application in the near future. Balloon- and stent-assisted coil embolization is enabling the treatment of complex, large-neck aneurysms and the vascular reconstruction of lesions previously considered not treatable. New open- and closed-cell designs allow the navigation and deployment of stents in extremely tortuous vessels. With regards to the embolization of vascular malformations, it is possible to safely navigate microcatheters and microwires through very small arteries previously considered not accessible. In addition, embolization materials such as n-butyl cyanoacrylate and ethylene-vinyl alcohol copolymer are now routinely injected to safely reduce or obliterate large and complex arteriovenous malformations and fistulae., Conclusions: Advancements in technology are rapidly improving the endovascular approach to the treatment of cerebral aneurysms and arteriovenous malformations.

Objectives: Achieving rapid, brain cooling has potentially important clinical implications. To investigate potential practicalities, we induced brain hypothermia in canines by perfusing cooled crystalloid solution into the carotid artery using an extracorporeal cooling-filtration system., Methods: Ringer's solution cooled to approximately 6.5 degrees C was infused at a rate of 3 ml/kg/min for 30 minutes into the right common carotid artery through an angiographic catheter via the right femoral artery in six adult canines (13.81 +/- 0.60 kg). Excessive fluid was ultrafiltrated through a venovenous extracorporeal circuit via the right femoral vein. Temperature was monitored in the cerebral hemispheres, the rectum and the vena cava. The extracellular lactate concentrations were measured by microdialysis in the frontal lobes., Results: Right brain temperature decreased to 33.6 +/- 2.0 degrees C from 37.7 +/- 1.1 degrees C 30 minutes after initiation of perfusion, while left brain and rectal temperatures were 34.3 +/- 1.7 and 34.1 +/- 1.3 degrees C, respectively. The cooling rate of the right cerebral hemisphere was 4.2 +/- 1.1 degrees C/ 30 minutes and advanced compared with the rectum (p<0.01), the left cerebral hemisphere and the vena cava (both p<0.05). There was no significant increase in the extracellular lactate concentrations in the cerebral hemispheres. Hemoglobin, hematocrit and cardiac function significantly changed during perfusion (p<0.05)., Conclusions: Brain hypothermia was rapidly and safely induced using an intra-arterial crystalloid infusion and an extracorporeal cooing-filtration system. With refinement and further assessment of metabolic and physiologic parameters, the method holds a potential for clinical utility.

Objective: Giant (>or=25 mm in diameter) cerebral aneurysms have a poor natural history, with high risks of subarachnoid hemorrhage or progressive disability or death caused by mass effect or stroke. Surgical treatment may be effective but carries a high burden of morbidity and mortality. Thus, attempts at endovascular solutions to these complex lesions have been developed to offer therapy at reduced risk., Methods: The authors reviewed their clinical experience and the current body of literature concerning giant cerebral aneurysms and present their perspective on the current state of the art in endovascular therapy for these aneurysms. A variety of techniques are described that can be used in an attempt to provide a solution to the wide variety of clinical dilemmas associated with the management of these difficult lesions. Preprocedural planning and periprocedural considerations are discussed briefly. The use of intracranial balloons and stents are described in conjunction with the use of detachable platinum coils. The developing concept of using stents alone to treat aneurysms is discussed. Alternative methods of treating giant aneurysms are discussed., Results: Current endovascular approaches, when properly selected and applied, can provide lower-risk therapies than conventional microsurgical approaches for patients harboring giant cerebral aneurysms. However, endovascular approaches do not, at present, provide results that are as durable as current surgical techniques for giant cerebral aneurysms., Conclusion: Treatment of giant cerebral aneurysms via endovascular therapeutics requires the interventionist to possess an extensive armamentarium. Meticulous preprocedure evaluation, patient selection, and execution of the treatment plan enable safe and effective management. Current therapies do not provide an ideal solution for every patient, so one must consider creative and evolving solutions to these difficult clinical challenges. The procedural morbidity of open surgery versus the decreased durability of current endovascular techniques must be assessed carefully.

Few could have imagined the tremendous growth of endovascular surgery over the past 40 years. Endovascular therapy has greatly enhanced the care of the patient in neurosurgery, spine surgery, and head and neck surgery. Progress in technology and techniques continue to push forward the boundaries of what is deemed "treatable," assuming acceptable risk. This article will briefly review the current state of endovascular surgery and speculate about what its role will be in the near and far future. Endovascular therapy provides a minimally invasive approach to the central nervous system and other systems via natural and, at times, highly selective pathways. Maximizing the accessibility of these routes to highly specific regions of the central nervous system provides an elegant and minimalist approach to treating diseases of the central nervous system with almost no "footprints" of ever having accessed the region. In the future, safe, efficient and intelligent delivery systems that may enhance or alter the tissue's response may result in successful treatment of cerebrovascular diseases, as well as other diseases of the craniospinal axis. The growth of nanotechnology, metallurgy, synthetic polymers, imaging, and training will all combine to help grow the technology and the science that is surgical endovascular neuroradiology.

Cerebral vasospasm remains a leading cause of death and disability in patients with ruptured cerebral aneurysms. The development of endovascular intervention in the past two decades has shown promising results in the treatment of vasospasm. Endovascular techniques that have been used in humans include intra-arterial infusion of vasorelaxants and direct mechanical dilation with transluminal balloon angioplasty. This article reviews the current indications and role of endovascular therapy in the management of cerebral vasospasm, its clinical significance, and potential future therapies.

Neuroendovascular embolization represents a critical component of the multidisciplinary management of cerebral arteriovenous malformations. Safe and effective embolization may be performed only in the context of a well-designed, rational treatment plan that is fundamentally based on a clear understanding of the natural history of the lesion, as well as the cumulative risks of multimodality treatment. This article outlines the role of neuroendovascular embolization in arteriovenous malformation therapy with a specific emphasis on decision making in the context of formulating a treatment plan. The authors also provide a summary of the available embolic agents and their technical application, potential intraprocedural and periprocedural complications, and postprocedural management.

Objective: The purposes of this article are to summarize recent developments and concerns in endovascular aneurysm therapy leading to the adjunctive use of endoluminal devices, to review the published literature on stent-supported coil embolization of cerebral aneurysms, and to describe our experience with this technique in a limited subgroup of problematic complex aneurysms over a medium-term follow-up period., Methods: Between January 2003 and June 2004, 28 individuals among 157 patients with cerebral aneurysms we evaluated were identified as harboring aneurysms with exceptionally broad necks. Out of these 28 patients, 16 were treated with a combination of stents and detachable coils, preserving the parent artery. Recorded data included patient demographics, the clinical presentation, aneurysm location and characteristics, procedural details, and clinical and angiographic outcome., Results: Over an 18-month period, 16 patients with large cerebral aneurysms additionally characterized by neck sizes between 7 and 14 mm were treated, using combined coil embolization of the aneurysm with stent reconstruction of the aneurysm neck. Thirteen out of the 16 aneurysms were occluded at angiographic reevaluation between 11 and 24 months (mean angiographic follow-up, 17.5 mo). There were no treatment-related deaths or clinically evident neurological complications. Thirteen patients experienced excellent clinical outcomes, with good outcomes in two patients and a poor visual outcome in one patient (mean clinical follow-up, 29 mo). A single technical complication occurred, involving transient nonocclusive stent-associated thrombus, which was treated uneventfully with abciximab., Conclusion: Stent-supported coil embolization of large, complex-neck cerebral aneurysms seems to provide superior medium-term anatomic reconstruction of the parent artery compared with historic series of aneurysms treated exclusively with endosaccular coils. In the near future, increasingly sophisticated endoluminal devices offering higher coverage of the neck defect will likely enable more definitive endovascular treatment of complex cerebral aneurysms and further expand our ability to manipulate the vascular biology of the parent artery.

The treatment of giant aneurysms remains a formidable challenge for endovascular and surgical strategies. The use of endovascular techniques in a deconstructive (e.g., parent vessel occlusion) and reconstructive (e.g., stent coiling) methodology is reviewed. The results of endovascular coiling as a primary therapy for giant aneurysm occlusion have been disappointing. Hunterian strategies have had more success in published series, but recent developments in coil, glue, and stent technology show great promise in allowing parent vessel reconstruction as a primary endovascular target, with acceptable morbidity, mortality, and durability. A literature review of giant aneurysm endovascular treatment strategies was undertaken after 1994, when Guglielmi detachable coils were approved by the Food and Drug Administration. Where possible, follow-up, durability, and occlusion rates are also reviewed.

Objective: Giant intracranial aneurysms present unique therapeutic intricacies. The purpose of this study was to evaluate the anatomic and hemodynamic characteristics of these lesions and the current endovascular and combined surgical and endovascular techniques available for their treatment., Methods: A review of the literature and the personal experiences of the authors with endovascular treatment of giant aneurysms are presented. This review included anatomic and hemodynamic features and analysis of the diverse endovascular techniques that have been reported for the management of these aneurysms., Results: Anatomic features that create particular challenges in the therapeutic approach of giant aneurysms include size, shape (saccular, fusiform, serpentine), neck dimensions, branch involvement, intraluminal thrombosis, and location. Hemodynamic characteristics that affect endovascular treatment are lateral or terminal aneurysm type of flow and embolic material placement (inflow versus outflow aneurysmal region). The current endovascular therapeutic approaches include parent artery occlusion, trapping, endosaccular embolization with or without adjunctive techniques such as balloon-assisted or stent placement, and combined surgical and endovascular approaches, mainly with surgical revascularization and endovascular occlusion., Conclusion: Although there are a wide variety of endovascular therapeutic options for the treatment of giant intracranial aneurysms, none of the current techniques is completely successful and free of complications in the management of these complex lesions. A detailed and individualized analysis of each case in conjunction with sufficient understanding of the anatomy and hemodynamics of a particular aneurysm should guide the therapeutic decision. Further research advances will assist in elucidating the factors predisposing to genesis, progression, and aggressive clinical manifestations of these giant lesions.

The three therapeutic modalities for arteriovenous malformation (AVM) treatment (surgery, embolization, and radiotherapy) developed in the past years with specific tools, each tool with its own qualities. Soon after the implementation of embolization for treatment of AVMs, this technique was used in combination with microsurgery; since the development of radiosurgery, treatment algorithms combining embolization with surgery and eventual subsequent radiosurgery, embolization with radiosurgery, or surgery with subsequent radiosurgery have been reported. These different combinations have been in use under the term multimodality treatment for many years, but the algorithms regarding the combination of tools, which tool has priority, and how the risk levels of each tool are assessed shows great variability among institutions. Centers with a surgical background see embolization as a technique to increase surgical feasibility and radiosurgery as a tool to complete subtotal AVM excision. Institutions with an endovascular background embolize AVMs with the aim of maximal occlusion rates and view surgery or radiosurgery as a technique to be used if the goal of total endovascular occlusion cannot be achieved. Radiosurgeons receive patients after incomplete embolization or surgical extirpation or a combination of both.

Endovascular neurosurgical procedures are complex, requiring significant planning, foresight, and coordination. The neuroanesthetist is an integral part of these procedures, organizing efforts of the technicians and nurses and responding to the needs of the neurointerventionalist. The purpose of this article is to review, in detail, the role of the neuroanesthetist in the endovascular operating room. An overview of all areas either partially or completely managed by the anesthetist is provided.

Objective: The past 15 years have seen a revolution in the treatment of intracranial aneurysms. Endovascular technology has evolved rapidly since the Food and Drug Administration approval of Guglielmi detachable coils in 1995, which now allows successful treatment of most aneurysms. The authors provide a review of their 11-year experience at Jefferson Hospital for Neuroscience with endovascular embolization of intracranial aneurysms and discuss clinical trial outcomes and future directions of this treatment method., Methods: The authors reviewed the clinical and angiographic outcomes for 1307 patients undergoing endovascular treatment of intracranial aneurysms. Their analysis focuses on posterior circulation and middle cerebral artery aneurysms, as well as cases of stent-assisted coil embolization. They review their procedural protocol and patient selection criteria for endovascular management., Results: Several large clinical trials have demonstrated the safety and efficacy of endovascular treatment of intracranial aneurysms. The International Subarachnoid Aneurysm Trial provides Level I evidence demonstrating a significant reduction in disability or death with endovascular treatment compared with surgical clipping. The most common procedural complications include intraprocedural rupture and thromboembolic events; avoidance strategies are also discussed. Vasospasm after subarachnoid hemorrhage causes neurological morbidity and mortality and can be successfully managed by early recognition and interventional treatment with angioplasty, pharmacologic agents, or both., Conclusion: Long-term studies evaluating experience with aneurysm coil embolization during the past decade indicate that this is a safe and durable treatment method. The introduction of stent-assist techniques has improved the management of wide-neck aneurysms. Future technology developments will likely improve the durability of endovascular treatment further by delivering bioactive agents that promote aneurysm thrombosis beyond the coil mass alone. It is clear that endovascular therapy of both ruptured and unruptured aneurysms is becoming a mainstay of practice in this patient population. Although not replacing open surgery, the continued improvements have allowed aneurysms that previously were amenable only to open clip ligation to be treated safely with durable long-term outcomes.

The rapid evolution of catheter-based technologies during the last 5 years has created a critical need for development of effective resident level and postgraduate education programs in both open and endovascular techniques and associated cognitive and clinical skills. Currently, significant variability exists in endovascular training formats and in the number of endovascular procedures performed during the course of a graduate or postgraduate program. Little information on the quality of these programs exists and in the subsequent practice patterns of the trainees. This report reviews recommended credentialing requirements, training paradigms, and the growing experience of vascular surgical trainees since 2000.

Balloon aortic valvuloplasty (BAV) has been a highly successful therapy for children and young adults with aortic valve stenosis, resulting in both symptomatic improvement and durable increases in the aortic valve area. Despite enthusiasm for BAV in older adult patients with aortic valve stenosis in the mid-1980s, the therapy has had disappointing medium- and long-term outcomes. Survival of patients with aortic valve stenosis does not increase with BAV, and restenosis occurs in the vast majority of patients within 6-24 months after therapy. Despite these limitations, most patients are symptomatically improved for a year or more. BAV remains an effective palliative therapy for selected patients.

The Foley catheter, introduced in the mid-1930s and originally manufactured from latex, is still the most commonly used device for the management of urinary incontinence (UI). Despite the passage of time, there are still problems associated with the use of these devices. It is currently estimated that the management and treatment of UI costs the UK National Health Service (NHS) in the order of 500 million pound per annum. Faced with the known demographic changes in the adult population these costs will continue to rise for the foreseeable future. This review examines the range of materials currently used to manufacture Foley catheters from both latex and silicone. It outlines the common problems associated with their clinical use-infection, encrustation and blockage. The main changes that have been made to the materials employed in response to these problems are analysed. In the first instance the use of controlled release glass and slow release polymers to introduce disinfectants and antibacterial agents is considered. Attempts to alter surface properties by using coatings based on silver, polytetrafluoroethylene (PTFE), hydrogels and silicone are then described. It can be seen that despite these approaches, problems remain with the design and materials currently used to manufacture catheters. The review concludes that changes to the materials currently used for the manufacture of commercially available catheters could potentially alleviate many of the existing problems. However, standards need to be developed in order to enable direct comparison of the mechanical and physical properties of existing and potential catheter designs to ensure their effective function in-service.

Haemophilia management is not uniform among countries, even within western Europe, that have close economic, social and cultural relationship. The European Paediatric Network PedNet aims to share experiences in the field of the care of boys with haemophilia. In 1998, a PedNet survey has shown significant disparities in 20 centres from 16 countries, particularly as regards the implementation of prophylaxis regimen. This survey has been updated in 2003 to describe the current status of haemophilia management in 22 centres and the changing pattern of care of boys with severe haemophilia in western Europe. Regular, continuous long-term prophylaxis is provided in all PedNet centres, more than 50% and 80-100% of boys being treated this way in 20/22 and 15/22 centres respectively. Twenty of the 22 centres (91%) recommend continuous prophylaxis (primary or secondary A) for a new patient. The use of recombinant factor VIII concentrates was already widespread in 1998 and a further expansion of recombinant products has been observed over the last 5 years. Recombinant FVIII is now used exclusively in nine centres and for more than 80% of boys with haemophilia A in nine other centres. The use of recombinant and plasma derived FIX is more balanced: among 18 centres where boys with haemophilia B are treated, 14 use recombinant FIX, and nine administer it to a majority of patients. Other modifications of practice have been stressed in this survey, such as more targeted use of central venous devices in the youngest boys and more extensive characterisation of genetic mutations.

Purpose of Review: Since its introduction 27 years ago by Andreas Gruntzig, interventional cardiology has expanded its scope from coronary disease to peripheral, congenital, and also valve diseases.Percutaneous mitral commissurotomy and aortic valvuloplasty have been performed since the mid 1980s. Balloon commissurotomy has been used in tens of thousands of patients worldwide and provides good short- and long-term results in a wide range of patients. It has virtually replaced surgical commissurotomy in the management of mitral stenosis. On the other hand, percutaneous aortic valvuloplasty is almost abandoned worldwide due to its lack of efficacy and the risks involved., Recent Findings: The new techniques of percutaneous valve intervention are aortic valve replacement, and mitral valve repair. Both are at an early stage since the first in-man applications only started in 2002. Preliminary series show that these techniques are feasible; however, they must be further evaluated in comparison with contemporary treatment to accurately assess efficacy and risks. Today potential applications concern high-risk patients, however, after thorough evaluation this may be extended to others in the future., Summary: Therefore, percutaneous interventions already play an important role in management of valvular heart disease, which is likely to grow in the future.

Percutaneous mitral commissurotomy and aortic valvuloplasty have been being performed since the mid-1980s. Balloon commissurotomy has been used in thousands of cases worldwide and it provides good short- and long-term results in a wide range of patients. It has virtually replaced surgical commissurotomy in the treatment of mitral stenosis. In contrast, percutaneous aortic valvuloplasty is almost abandoned worldwide due to its lack of efficacy and the risks involved. The new techniques of percutaneous valve intervention: aortic valve replacement and mitral valve repair are at an early stage: the first in-man applications of these fledgling techniques started in 2002. Preliminary series show that they are feasible; however, they need to be further evaluated in comparison with contemporary treatment to assess accurately how efficient they are and the risks involved. Currently potential applications concern high-risk patients, however, in the future, after thorough evaluation, this may be extended to others. Thus, percutaneous interventions already play an important role in treatment of valvular heart disease, a role that seems set for future expansion.