Toward magnetic resonance-guided electroanatomical voltage mapping for catheter ablation of scar-related ventricular tachycardia: a comparison of registration methods

Toward MR‐Guided Electroanatomical Voltage Mapping for Catheter Ablation. Introduction: Integration of preprocedural delayed enhanced magnetic resonance imaging (DE‐MRI) with electroanatomical voltage mapping (EAVM) may provide additional high‐resolution substrate information for catheter ablation of scar‐related ventricular tachycardias (VT). Accurate and fast image integration of DE‐MRI with EAVM is desirable for MR‐guided ablation. Methods and Results: Twenty‐six VT patients with large transmural scar underwent catheter ablation and preprocedural DE‐MRI. With different registration models and EAVM input, 3 image integration methods were evaluated and compared to the commercial registration module CartoMerge. The performance was evaluated both in terms of distance measure that describes surface matching, and correlation measure that describes actual scar correspondence. Compared to CartoMerge, the method that uses the translation‐and‐rotation model and high‐density EAVM input resulted in a registration error of 4.32±0.69 mm as compared to 4.84 ± 1.07 (P <0.05); the method that uses the translation model and high‐density EAVM input resulted in a registration error of 4.60 ± 0.65 mm (P = NS); and the method that uses the translation model and a single anatomical landmark input resulted in a registration error of 6.58 ± 1.63 mm (P < 0.05). No significant difference in scar correlation was observed between all 3 methods and CartoMerge (P = NS). Conclusions: During VT ablation procedures, accurate integration of EAVM and DE‐MRI can be achieved using a translation registration model and a single anatomical landmark. This model allows for image integration in minimal mapping time and is likely to reduce fluoroscopy time and increase procedure efficacy. (J Cardiovasc Electrophysiol, Vol. 23, pp. 74‐80, January 2012)     

Facilitators and Barriers to Teamworking and Patient Centeredness in Multidisciplinary Cancer Teams: Findings of a National Study

Background

Multidisciplinary teams (MDTs) are the standard means of making clinical decisions in surgical oncology. The aim of this study was to explore the views of MDT members regarding contribution to the MDT, representation of patients’ views, and dealing with disagreements in MDT meetings—issues that affect clinical decision making, but have not previously been addressed.

Methods

Responses to open questions from a 2009 national survey of MDT members about effective MDT working in the United Kingdom were analyzed for content. Emergent themes were identified and tabulated, and verbatim quotes were extracted to validate and illustrate themes.

Results

Free-text responses from 1,636 MDT members were analyzed. Key themes were: (1) the importance of nontechnical skills, organizational support, and good relationships between team members for effective teamworking; (2) recording of disagreements (potentially sharing them with patients) and the importance of patient-centered information in relation to team decision making; (3) the central role of clinical nurse specialists as the patient’s advocates, complementing the role of physicians in relation to patient centeredness.

Conclusions

Developing team members’ nontechnical skills and providing organizational support are necessary to help ensure that MDTs are delivering high-quality, patient-centered care. Recording dissent in decision making within the MDT is an important element, which should be defined further. The question of how best to represent the patient in MDT meetings also requires further exploration.     

The varicocele: diagnostic dilemmas,therapeutic challenges and future perspectives

A varicocele is defined as the abnormal dilation of the internal testicular vein and pampiniform venus plexus within the spermatic cord. If a semen analysis is not obtained from the adolescent male, in the absence of other symptoms, the main clinical indication used by many urologists to recommend repair is testicular atrophy. The varicocele may result in testicular damage in some males causing testicular atrophy with impaired sperm production and decreased Leydig cell function, while in other males the varicocele may seemingly cause no ill effects. In adult men, varicoceles are frequently present and surgically correctable, yet the measurable benefits of surgical repair are slight according to a Cochrane review. While occurring more commonly in infertile men than fertile men, only 20% of men with a documented varicocele will suffer from fertility problems. Most varicoceles found in adolescents are detected during a routine medical examination, and it is difficult to predict which adolescent presenting with a varicocele will ultimately show diminished testicular function in adolescence or adulthood. As in adults, the mainstay of treatment for varicocele in adolescents is surgical correction. However, unlike an adult varicocelectomy (the microsurgical approach is the most common), treatment for an adolescent varicocele is more often laparoscopic. Nevertheless, the goals of treatment are the same in the adolescent and adult patients. Controversy remains as to which patients to treat, when to initiate the treatment, and what type of treatment is the best. This review will present the current understanding of the etiology, diagnosis and treatment of the adolescent varicocele.     

A Modified AUGIS Delphi Process to Establish Future Research Priorities in Benign Upper Gastrointestinal Surgery

World Journal of Surgery - The aim of our study was to use a modified Delphi process to determine the research priorities amongst benign upper gastrointestinal (UGI) surgeons in the United Kingdom....     

The introduction of new critical care equipment into the aeromedical evacuation service of the Royal Air Force.

Changing world events over recent years and an increasingly complex patient casemix have led to a review of the equipment used by the Aeromedical Evacuation Squadron of the Royal Air Force. The initial special purpose aeromedical equipment (SPAME) project was completed in 2001 with the new equipment being brought into service in August of the same year. The project incorporated long term planning for replacing the equipment along with its rapidly developing technology, especially with that used for the care of the critically ill. An intensive training programme was simultaneously introduced to support the deployment of this new technology. Critical care teams comprise a consultant anaesthetist, a critical care nurse, a flight nurse attendant (paramedic) and a technician, all of whom attend courses designed specifically to accommodate their role within the team.A considerable amount of work has been undertaken by a dedicated team to ensure this project became a reality and which has resulted in the provision of care to meet the needs of any casualty, anywhere in the world, being achieved using the latest technology proportionate to any hospital-based ICU.     

Impact of Hypothermic Preservation on Tissue Yield and Viability in Pig Pancreata

Introduction

Chronic shortage of quality human cadaveric pancreata limits islet transplantation. Porcine islet xenotransplantation is being explored to increase the donor pool. For clinical-ready islets, centralized animal husbandry, Current Good Manufacturing Practice–regulated processing facilities, and organ transportation support are required. Amount of cold ischemia time (CIT) before isolation significantly affects transplantation. The goal of this study was to determine the maximum safe CIT of whole pancreata before islet isolation.

Materials and Methods

Pancreata were rapidly removed from Yorkshire pigs (age, 14–22 days) and stored in modified University of Wisconsin solution or in EuroCollins solution at 4^°C. Pancreata were processed with <1 hour CIT (control) or stored for 4 or 12 hours before isolation. Islet yield and percent purity and viability were determined after 7 days of in vitro tissue culture and maturation. Samples from nonprocessed pancreata were collected and snap-frozen in liquid nitrogen at 0, 3, 6, 9, 12, 15, and 24 hours of preservation, then analyzed for adenosine diphosphate/adenosine triphosphate ratio as a measure of tissue energetics.

Results

Up to 12 hours in cold storage had no significant impact on overall islet yield after 7 days of in vitro culture compared with controls; islet yield at the end of the maturation process was 28,700 ± 500 islet equivalents per pancreas (mean ± SEM control yield, 30,300 ± 900 islet equivalents per pancreas); islet purity was 75 ± 5% compared with 74 ± 5% in controls. Islet viability was significantly reduced at 12 hours compared with controls (80 ± 6% vs 96 ± 5%; P < .05). The tissue adenosine diphosphate/adenosine triphosphate ratio was maintained within the first 6 hours (1.6 ± 0.1 to 1.8 ± 0.2; P = NS) but was markedly increased during the 24-hour study (3.3 ± 0.1 at 24 hours), indicating a progressive loss of adenosine triphosphate tissue stores.

Conclusions

Young pig pancreata can be hypothermically stored for up to 12 hours without affecting islet yield and purity; however, islet viability is reduced. These data highlight the need for uniform shipping parameters to standardize islet quality, ideally with CIT <6 hours.