Search

Radiologic indicators of sarcopenia have been associated with adverse operative outcomes in some surgical populations. This study assesses the association of radiologic indicators of frailty with outcomes after open ventral hernia repair (OVHR). A prospective, institutional, herniaspecific database was queried for patients undergoing OVHR from 2007 to 2018 with preoperative CT. Psoas muscle cross-sectional area at L3 was measured and adjusted for height (skeletal muscle index (SMI)). L3 vertebral body density (L3 VBD) was measured. Demographics and outcomes were evaluated as related to SMI and L3 VBD. Of 1178 patients, 9.7 per cent of females and 15.8 per cent of males had sarcopenia and 11.6 per cent of females and 9.2 per cent of males had osteopenia. Neither sarcopenia nor osteopenia were associated with outcomes of wound infection, read-mission, reoperation, hernia recurrence, or major complications. When examined as continuous variables or by quartile, SMI and L3 VBD were not associated with adverse outcomes, including in subsets of male or female patients, the elderly, contaminated cases, and the obese. Radiologic markers of sarcopenia and osteopenia are not associated with adverse outcomes after OVHR. Further study should examine age or other potential predictors of outcomes in this patient population, such as independent status.

Surgical mesh and hernia repair have come under increasing scrutiny with large amounts of press, Internet, and social media reportage regarding ongoing mesh litigation, recalls, and patient testimonials. The aim of this study was to evaluate patient perceptions of mesh in hernia surgery.A 16-question survey was given to patients presenting for hernia surgery at a tertiary hernia center by trained data analysts before surgeon interaction.Two hundred and two patients were surveyed. Patients believed mesh caused complications (45.1%) and reported concerns about mesh (38.2%). Those who performed their own research, females, and patients with recurrent hernias were more likely to have concerns about mesh (P ≤ 0.03). Most patients (81.7%) thought they were at average risk or less for complications; patients with recurrent hernias (versus primary hernias) and incisional hernias (compared with inguinal or umbilical hernias) had more negative outlooks on complications (all P.05). Recovery expectations varied, but the failed repair and incisional hernia groups were more likely to expect prolonged recovery (3 months) (all P.05). After surgeon-directed education and a mesh education handout, all but one patient agreed to and underwent a mesh repair as indicated.Patients had concerns about mesh and were aware of mesh related complications. Patients performing their own research, as well as females and recurrent hernia patients, had worse perceptions of mesh. Recurrent and incisional hernia patients had greater concerns about complications, recurrence, and recovery. Preoperative education concerning mesh and mesh choice for each operation eased patient anxiety.

Wire bonds are used to connect device terminals to package terminals or substrate terminal that forms circuits that are needed to create desired higher level functions. If a wire bond breaks or becomes detached during operation, the desired function will be lost. Depending on the design, a loss in function could be catastrophic. Aluminum, gold, and copper wires are used to create wire bonds in electronic products. These materials have been selected for their ability to be formed as fine wires and their ability to provide low electrical resistance. In many electronics packages, wire bonds are encapsulated in a polymer molding compound that is used to protect the electronic device. However, in some electronic devices such as hermetically sealed cavity packages, wire bonds may be free-standing. Under vibration loading, free-standing wire bonds may be subject to failure due to mechanical fatigue. In this work, an analytic model is presented for predicting natural frequency of a free-standing wire bond and for assessing a wire bond time to failure under a harmonic loading condition. The model for natural frequency is calibrated by finite element analysis and validated through experimental testing. The life prediction model, a test plan, and preliminary test results are presented.

The oil and gas industry subsurface formation evaluation instruments experience significant challenging vibrations and shock levels. Equipment development requirements for these instruments include reliability and durability under these severe operating conditions. The engineering design for this equipment utilizes tools that enable the estimation of service lifetime, maintenance cycles, and related costs. These engineering tools model failure modes and their acceleration factors and how failures interact under certain circumstances. Laboratory test data and operations failure history are used to validate the model results. Incorporating equipment operational failure history into the reliability design after failure analysis, enables determination of failure modes and the length of stress level exposure. Before the equipment is commissioned to field operational service, it is subjected to a batch of environmental qualification tests under objective pass-fail criteria. The environmental qualification test conditions and adopted stress levels are acquired through measurements made with sensors (temperature, acceleration, and shock) in the equipment assembly during field operational conditions in targeted environments. After the equipment passes the qualification tests and final inspection, it is commissioned to field commercial service. This paper studies the development of specific equipment failures during operational field deployment after they were subjected to standard environmental qualifications tests. Various investigative actions focused on determining the cause and circumstances that led to the unexpected field failure. Results helped to introduce corrective updates to the equipment design and manufacturing, durability and reliability design models and procedures, environmental stress levels, and corresponding qualification test conditions. The equipment failures were examined, and comprehensive 3D custom vibration and stress modeling were conducted for the entire equipment assembly and each assembly module. The modeling results pinpointed and confirmed the high stress levels in the failure areas. These high stress levels exceeded the assembly construction strength thresholds, causing failures. The equipment assembly was modified and reinforced to properly support the detected stresses and provide the required lifetime reliability and durability for the operational service. A full 3D model of the equipment assembly was used for the vibration and bending load analysis including all mechanical assembly parts, electronics modules, couplings, and attachments. The 3D model was meshed with Tet and Hex elements in ANSYS application software, failure-prone and critical regions were meshed with finer divisions. In this analysis the electronics modules assembly were considered with all parts, attachments, structural frames, linkages, carriers, and printed circuit board (PCB) modules properly attached and connected to the main chassis structural carrier. Geometries, mass, module and assembly attachments, and material properties were assigned to components in this model. External loads and boundary conditions environmentally imposed to the assembly were applied in the model. Environmental conditions, shock, and vibration (x, y, and z) recorded from similar equipment deployed in subsurface operations in equivalent wells and geological formations were used in the modeling parameters. Displacement modeling data and analysis was performed for all mechanical structural components, PCB electronics module assemblies and assembly components, and module electronics component attachments. A model harmonic analysis under static conditions was performed to detect the oscillatory modes and vibratory resonances and the extent of oscillatory displacements. A structural and main carrier chassis modal analysis was conducted for the entire model, identifying the dominant oscillatory modes and natural structural oscillatory frequencies. The displacement can be used for detection of maximum allowable plastic deformation threshold and cyclic fatigue analysis of attachments, structural support members, and linkages for equipment service lifetime durability and reliability assessment. Past field instrumented operational conditions with documented failures and lab characterization of failure modes along with failure behavior and failure triggering thresholds have provided limits for the mechanical and electronics assembly technology with maximum acceleration level of random vibration and maximum equivalent stress level tolerated by the equipment's structural assembly, standard design techniques, and materials. With these structural stress and displacement limits the 3D modeling results were inspected for the entire assembly, identifying the points in the mesh model where these limits were exceeded. The inspection determined that these recommended limits had been exceeded according to the model results, placing a reduced importance to the adjustment of tolerable maximum stresses and displacements. The mesh points with excessive stress and displacement-induced fatigue coincided with the areas where field failure had been detected in examined field failed units. Because of this modeled assembly performance result and details from the externally imposed operational shocks and vibration, the equipment mechanical and electronics assembly structural design were re-engineered to produce an updated model simulation results that did not exceed the demonstrated cumulative failure threshold stresses in lab tests and field operations. The modified equipment assembly was built and environmentally re-tested in the lab environment with more instrumentation points and scrutiny around the failure critical areas. The test results were successful. After deployment of the new and updated equipment assembly version, its field deployment has not observed similar field failures compared with the previous design version. These modeling and engineering tools, qualification test procedures, and methods can be used to validate a new design or understand the most effective and economical approach to iterate the design before it is launched to field operations or after a field failure.

Background Male and female hernia patients often have different surgical history, fat distribution, and medical comorbidities. Female surgical patients seemingly experience worse outcomes after open ventral hernia repair. This study evaluates the impact of sex and the distribution of abdominal adiposity on outcomes after open ventral hernia repair. Methods A prospective hernia database was queried for patients from 2007 to 2018 with a computed tomography within 1 year of open ventral hernia repair. Three-dimensional volumetric analysis was performed. Demographics, abdominal fat distribution, operative characteristics, and outcomes were evaluated by sex using univariate and multivariate analysis. Results A total of 1,178 patients were identified, 57.8% were female. Compared with males, females had higher mean body mass index (34.8 ± 8.5 vs 31.7 ± 6.4 kg/m2, P Conclusion Female hernia patients in our population are more comorbid, with higher body mass index, thicker subcutaneous fat volume and a higher ratio of hernia volume to intra-abdominal fat volume. These differences are associated with more extensive surgical intervention, such as panniculectomy and higher rates of adverse outcomes after open ventral hernia repair. However, these differences are not fully explained by identified comorbidities and warrant further investigation.

Introduction Several countries in southern Africa have made significant progress towards reaching the Joint United Nations Programme on HIV/AIDS goal of ensuring that 90% of people living with HIV are aware of their status. In Zimbabwe, progress towards this “first 90” was estimated at 73% in 2016. To reach the remaining people living with HIV who have undiagnosed infection, the Zimbabwe Ministry of Health and Child Care has been promoting index testing and partner notification services (PNS). We describe the implementation of index testing and PNS under the Zimbabwe HIV Care and Treatment (ZHCT) project and the resulting uptake, HIV positivity rate and links to HIV treatment. Methods The ZHCT project has been implemented since March 2016, covering a total of 12 districts in three provinces. To assess the project's performance on index testing, we extracted data on HIV testing from the district health information system (DHIS 2) from March 2016 to May 2018, validated it using service registers and calculated monthly HIV positivity rates using Microsoft Excel. Data were disaggregated by district, province, sex and service delivery point. We used SPSS to assess for statistical differences in paired monthly HIV positivity rates by sex, testing site, and province. Results The average HIV positivity rate rose from 10% during the first six months of implementation to more than 30% by August 2016 and was sustained above 30% through May 2018. The overall facility HIV positivity rate was 4.1% during the same period. The high HIV positivity rate was achieved for both males and females (mean monthly HIV positivity rate of 31.3% for males and 33.7% for females), with females showing significantly higher positivity compared to males (p

The engineering task to design a highly reliable printed circuit board assembly (PCBA) that can withstand high temperatures and vibration stress is a challenge faced by all downhole electronics designers in the oil and gas industry today. Discussion will focus a comprehensive Design for Reliability (DfR) process flow based on complementary use of computer-aided design (CAD) tools. The DfR can enable analysis of the PCBA electrical, vibration and thermal stresses, service life prediction, mean time between failure (MTBF) and identify potential design errors for iterative reliability improvement on the schematic-level, early in the design cycle. Stress analysis using CAD tools includes reliability risk assessment based on historical failures (i.e., engineering practice), detects uncertain design errors, and provides MTBF predictions and life predictions for the PCBA. This approach could improve PCBA performance and reliability by and reducing the product design cost and development time including the design qualification test. The process could accelerate the product development's time-to-market, increase customer satisfaction, and save product development costs. This paper discusses a case study used to evaluate this CAD-based DfR methodology. The paper also describes how the methodology can be used to support durability analysis at the early design stage.

Objectives Somatic development is impaired in children with congenital heart defects (CHDs), and head circumference seems to be a strong predictor of neurodevelopmental prognosis. The aim of this study was to generate up-to-date reference values for the somatic development (head circumference, body weight, and length/height) of children with CHDs. Study design Our study population consisted of all patients included in the PAN study (Pravalenz angeborener Herzfehler bei Neugeborenen in Deutschland), which was conducted prospectively over a 3-year study period by the Competence Network for Congenital Heart Defects. All children with mild, moderate, and severe CHDs born in 2006-2009 in Germany were enrolled. For computing of z-scores, only children with the following characteristics were included: appropriate for gestational age, nonsyndromic disease, term or post-term delivery, and no cardiac surgery. Results There were 2818 patients included. New z-scores for the described somatic measures of children with mild, moderate, and severe CHDs were computed. Comparisons with the KiGGS study (Gesundheit von Kindern und Jugendlichen in Deutschland) and the Berlin Longitudinal Study revealed significantly lower measurements for all measures—most notably in children with severe CHDs and/or cardiac surgery. In our cohort, no catch-up growth was seen after cardiac surgery. Conclusion Children with severe CHDs demonstrated the most abnormal pattern in growth, including head circumference before and after cardiac surgery, which is indicative of accompanying brain pathology unrelated to operative injury.

An internationally approved and globally used classification scheme for the diagnosis of CHD has long been sought. The International Paediatric and Congenital Cardiac Code (IPCCC), which was produced and has been maintained by the International Society for Nomenclature of Paediatric and Congenital Heart Disease (the International Nomenclature Society), is used widely, but has spawned many “short list” versions that differ in content depending on the user. Thus, efforts to have a uniform identification of patients with CHD using a single up-to-date and coordinated nomenclature system continue to be thwarted, even if a common nomenclature has been used as a basis for composing various “short lists”. In an attempt to solve this problem, the International Nomenclature Society has linked its efforts with those of the World Health Organization to obtain a globally accepted nomenclature tree for CHD within the 11th iteration of the International Classification of Diseases (ICD-11). The International Nomenclature Society has submitted a hierarchical nomenclature tree for CHD to the World Health Organization that is expected to serve increasingly as the “short list” for all communities interested in coding for congenital cardiology. This article reviews the history of the International Classification of Diseases and of the IPCCC, and outlines the process used in developing the ICD-11 congenital cardiac disease diagnostic list and the definitions for each term on the list. An overview of the content of the congenital heart anomaly section of the Foundation Component of ICD-11, published herein in its entirety, is also included. Future plans for the International Nomenclature Society include linking again with the World Health Organization to tackle procedural nomenclature as it relates to cardiac malformations. By doing so, the Society will continue its role in standardising nomenclature for CHD across the globe, thereby promoting research and better outcomes for fetuses, children, and adults with congenital heart anomalies.

Dielectric logging can be used to quantify water saturation, water resistivity and textural properties of formation. Application of this log is especially useful in situations where the resistivity of water is unknown or it varies considerably at different depth. This logging is based on the contrast between the dispersive dielectric behavior of dry matrix, hydrocarbon and water as elements present in the rock. As such the real and imaginary parts of dielectric dispersion at various frequencies are used to infer the petro-physical properties of formation. The wide frequency of operation, large dynamic range of response and numerous parameters involved make the interpretation of data challenging especially in the presence of noisy environment. This paper takes a look at a method to define quality control criteria for dielectric logging. As any other measurements the quality of recorded data should be judged based on the acceptable range of variations for inferred parameters as well as related confidence levels. These would lead to an acceptable noise level in the recorded data. Having access to the aforementioned quality control criteria can be very useful for example when the tool response is measured in a predetermined environment and it is compared with expected values or when the response of symmetrically positioned transmitters are compared assuming that tool is facing a homogeneous medium. In this paper a petro-physically driven quality control method is presented for dielectric logging. It uses a probabilistic Bayesian inference method in obtaining the required accuracy level for dielectric tool response. The criterion is defined in a way that guarantees the inverted petro-physical parameters will be within a predefined range around the actual values with a required confidence level. The application of method is shown through few examples.

Significant advances have been made in the care of children with cardiac disease. Most advances have been guided by anatomical and functional understanding of the changes from normal imposed by the cardiac malformations. As survival has increased, it has become rare to obtain untreated and unaltered hearts for morphologic examination. This limited availability of new specimens, coupled with the inevitable deterioration of currently available specimens, means that alternative methods of "preservation" become increasingly important. In this review, we propose and outline a format for the development of a Global Virtual Museum of Congenital Cardiac Pathology , based on established principles of anatomical analysis, classification based on an internationally accepted nomenclature (The International Pediatric and Congenital Cardiac Code or IPCCC), and the use of digital methods of storage of images and videos. In this fashion, we hope to preserve, in a virtual sense, the currently available anatomical specimens.

Interventional cardiology for paediatric and congenital cardiac disease is a relatively young and rapidly evolving field. As the profession begins to establish multi-institutional databases, a universal system of nomenclature is necessary for the field of interventional cardiology for paediatric and congenital cardiac disease. The purpose of this paper is to present the results of the efforts of The International Society for Nomenclature of Paediatric and Congenital Heart Disease to establish a system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease, focusing both on procedural nomenclature and on the nomenclature of complications associated with interventional cardiology. This system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease is a component of The International Paediatric and Congenital Cardiac Code. This manuscript is the first part of a two-part series. Part 1 will cover the procedural nomenclature associated with interventional cardiology as treatment for paediatric and congenital cardiac disease. This procedural nomenclature of The International Paediatric and Congenital Cardiac Code will be used in the IMPACT Registry™ (IMproving Pediatric and Adult Congenital Treatment) of the National Cardiovascular Data Registry®of The American College of Cardiology. Part 2 will cover the nomenclature of complications associated with interventional cardiology as treatment for paediatric and congenital cardiac disease.

Tremendous progress has been made in the field of pediatric heart disease over the past 30 years. Although survival after heart surgery in children has improved dramatically, complications still occur, and optimization of outcomes for all patients remains a challenge. To improve outcomes, collaborative efforts are required and ultimately depend on the possibility of using a common language when discussing pediatric and congenital heart disease. Such a universal language has been developed and named the International Pediatric and Congenital Cardiac Code (IPCCC). To make the IPCCC more universally understood, efforts are under way to link the IPCCC to pictures and videos. The Archiving Working Group is an organization composed of leaders within the international pediatric cardiac medical community and part of the International Society for Nomenclature of Paediatric and Congenital Heart Disease ( www.ipccc.net ). Its purpose is to illustrate, with representative images of all types and formats, the pertinent aspects of cardiac diseases that affect neonates, infants, children, and adults with congenital heart disease, using the codes and definitions associated with the IPCCC as the organizational backbone. The Archiving Working Group certifies and links images and videos to the appropriate term and definition in the IPCCC. These images and videos are then displayed in an electronic format on the Internet. The purpose of this publication is to report the recent progress made by the Archiving Working Group in establishing an Internet-based, image encyclopedia that is based on the standards of the IPCCC.

In 2000, The International Nomenclature Committee for Pediatric and Congenital Heart Disease was established. This committee eventually evolved into the International Society for Nomenclature of Paediatric and Congenital Heart Disease. The working component of this international nomenclature society has been The International Working Group for Mapping and Coding of Nomenclatures for Paediatric and Congenital Heart Disease, also known as the Nomenclature Working Group. The Nomenclature Working Group created the International Paediatric and Congenital Cardiac Code, which is available for free download from the internet at [http://www.IPCCC.NET].In previous publications from the Nomenclature Working Group, unity has been produced by cross-mapping separate systems for coding, as for example in the treatment of the functionally univentricular heart, hypoplastic left heart syndrome, or congenitally corrected transposition. In this manuscript, we review the nomenclature, definition, and classification of heterotaxy, also known as the heterotaxy syndrome, placing special emphasis on the philosophical approach taken by both the Bostonian school of segmental notation developed from the teachings of Van Praagh, and the European school of sequential segmental analysis. The Nomenclature Working Group offers the following definition for the term “heterotaxy”: “Heterotaxy is synonymous with ‘visceral heterotaxy’ and ‘heterotaxy syndrome’. Heterotaxy is defined as an abnormality where the internal thoraco-abdominal organs demonstrate abnormal arrangement across the left-right axis of the body. By convention, heterotaxy does not include patients with either the expected usual or normal arrangement of the internal organs along the left-right axis, also known as ‘situs solitus’, nor patients with complete mirror-imaged arrangement of the internal organs along the left-right axis also known as ‘situs inversus’.” “Situs ambiguus is defined as an abnormality in which there are components of situs solitus and situs inversus in the same person. Situs ambiguus, therefore, can be considered to be present when the thoracic and abdominal organs are positioned in such a way with respect to each other as to be not clearly lateralised and thus have neither the usual, or normal, nor the mirror-imaged arrangements.”The heterotaxy syndrome as thus defined is typically associated with complex cardiovascular malformations. Proper description of the heart in patients with this syndrome requires complete description of both the cardiac relations and the junctional connections of the cardiac segments, with documentation of the arrangement of the atrial appendages, the ventricular topology, the nature of the unions of the segments across the atrioventricular and the ventriculoarterial junctions, the infundibular morphologies, and the relationships of the arterial trunks in space. The position of the heart in the chest, and the orientation of the cardiac apex, must also be described separately. Particular attention is required for the venoatrial connections, since these are so often abnormal. The malformations within the heart are then analysed and described separately as for any patient with suspected congenital cardiac disease. The relationship and arrangement of the remaining thoraco-abdominal organs, including the spleen, the lungs, and the intestines, also must be described separately, because, although common patterns of association have been identified, there are frequent exceptions to these common patterns. One of the clinically important implications of heterotaxy syndrome is that splenic abnormalities are common. Investigation of any patient with the cardiac findings associated with heterotaxy, therefore, should include analysis of splenic morphology. The less than perfect association between the state of the spleen and the form of heart disease implies that splenic morphology should be investigated in all forms of heterotaxy, regardless of the type of cardiac disease. The splenic morphology should not be used to stratify the form of disease within the heart, and the form of cardiac disease should not be used to stratify the state of the spleen. Intestinal malrotation is another frequently associated lesion that must be considered. Some advocate that all patients with heterotaxy, especially those with isomerism of the right atrial appendages or asplenia syndrome, should have a barium study to evaluate for intestinal malrotation, given the associated potential morbidity. The cardiac anatomy and associated cardiac malformations, as well as the relationship and arrangement of the remaining thoraco-abdominal organs, must be described separately. It is only by utilizing this stepwise and logical progression of analysis that it becomes possible to describe correctly, and to classify properly, patients with heterotaxy.

There are many reasons for seeking to create a global database with which to record the outcomes of therapy for congenital heart disease. Such a database can function as a tool to support a variety of purposes

For many years, paediatric cardiologists and paediatric cardiac surgeons have felt the need for a common diagnostic and therapeutic coding system with which to classify patients of all ages with congenital and acquired heart disease. This desire has been highlighted by the recent, and ongoing, enquiry into the outcome of paediatric cardiac surgery at the unit in Bristol, in the United Kingdom, and the resulting obligation to provide national and international comparisons of surgical results between centres caring for these patients. In order to incorporate effective clinical governance and best practice into our speciality, a method is required to gather accurate and validated data on the diagnosis, therapy and outcome of patients with heart disease from prenatal life through to adulthood. This would facilitate comparisons between individual units which fully take into account the mix of cases involved, and thus attempt to focus on the relevant and genuine factors underlying the differing outcomes in terms of both mortality and morbidity. For this to be achieved, it is essential to have a comprehensive system of coding and classification, using mutually exclusive and unambivalent terms. The system must be both easy to use, and fulfil the needs and expectations of widely different cultures of practice. Although many centres have developed their own system of internal audit, with their own coding system, and some co-operation has taken place between centres nationally and across international boundaries within Europe by the European Congenital Heart Surgeons Federation (see below), a cohesive, and comprehensive system suitable for setting standards has yet to emerge. Historically, this has partly been due to the lack of recognition by governments of the importance of such a process, with underfunding of initiatives aimed at addressing these issues, both technologically and in terms of human resources.

Background. There is some evidence that continuous warm blood cardioplegia offers good myocardial protection; however, the effects of interrupting cardioplegia remain controversial. To study this, we compared the effects of continuous and intermittent antegrade warm (37°C) blood cardioplegia on functional recovery after prolonged cardiac arrest (180 minutes). Methods. Twenty-four juvenile pigs were randomly assigned into four groups. Group 1 received continuous cardioplegia, group 2 underwent several periods of 15 minutes of cardioplegia interrupted by 5 minutes of normothermic ischemia, and group 3 underwent several periods of 10 minutes of cardioplegia interrupted by episodes of 10 minutes. The hearts of group 4 received no cardioplegia. Left ventricular systolic function was assessed from fractional left ventricular shortening and percentage left ventricular wall thickening, and left ventricular diastolic function was determined from the time constant of relaxation and the constant of myocardial stiffness. Results. Systolic and diastolic functions were slightly depressed 1 and 2 hours after cross-clamp removal in all four groups, without significant differences among the groups. Conclusions. These data suggest that antegrade warm blood cardioplegia can be interrupted for up to 10 minutes without obvious negative effects on left ventricular function in the normal myocardium, provided that the intermittent doses of cardioplegia are sufficient to restore the metabolic demands of the arrested myocardium.

The role of coronary tortuosity in the pathophysiology of chronic pressure and volume overload is still unclear. A new method for measuring coronary tortuosity in patients with chronic pressure and volume overload was evaluated in 62 patients. Sixteen controls, 14 patients with arterial hypertension, and 32 patients with aortic regurgitation were included in the present analysis. The left anterior descending (LAD) and circumflex (LCX) coronary arteries were traced, and tortuosity was determined in the 30 degrees right (RAO) and 60 degrees left (LAO) anterior oblique projection. Tortuosity index (TI, %) was defined as the percent ratio of calculated shortest distance divided by total length of the coronary artery. TI was 104.1 +/- 3.2% at end-diastole in controls, 105.7 +/- 3.8% in hypertensives (P < 0.05 vs. controls), and 102.9 +/- 2.5% in patients with aortic regurgitation (P < 0.05 vs. controls, P < 0.001 vs. hypertensives). Respective values at end-systole were 107.8 +/- 4.7% in controls, 109.8 +/- 7.1% in hypertensives (ns vs. controls), and 104.3 +/- 3.3% in patients with aortic regurgitation (P < 0.001 vs. controls and vs. hypertensives). No differences were found in tortuosity between RAO and LAO projection or between LAD and LCX artery. There was a significant correlation between TI and left ventricular (LV) muscle mass, LV volume, and age. Females tended to have more tortuous vessels than males. Coronary tortuosity is more pronounced in patients with chronic pressure than with volume overload. Determinants of coronary tortuosity are gender, age, LV volume, and muscle mass. Thus, coronary tortuosity seems to play an important role as a physiologic determinant for the flow and the mechanics of the vessel wall.

Interventional cardiology for paediatric and congenital cardiac disease is a relatively young and rapidly evolving field. As the profession begins to establish multi-institutional databases, a universal system of nomenclature is necessary for the field of interventional cardiology for paediatric and congenital cardiac disease. The purpose of this paper is to present the results of the efforts of The International Society for Nomenclature of Paediatric and Congenital Heart Disease to establish a system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease, focusing both on procedural nomenclature and the nomenclature of complications associated with interventional cardiology. This system of nomenclature for cardiovascular catheterisation for congenital and paediatric cardiac disease is a component of The International Paediatric and Congenital Cardiac Code. This manuscript is the second part of the two-part series. Part 1 covered the procedural nomenclature associated with interventional cardiology as treatment for paediatric and congenital cardiac disease. Part 2 will cover the nomenclature of complications associated with interventional cardiology as treatment for paediatric and congenital cardiac disease.

The relationship between coronary artery size and left ventricular (LV) muscle mass was studied in 10 control subjects and in 10 patients with chronic mitral regurgitation before and 28 +/- 15 months after mitral valve surgery. Left and right coronary artery size was determined by quantitative coronary arteriography. Left coronary artery size was significantly increased before surgery (26 mm2) and decreased after operation (23 mm2), but was still larger than in control subjects (14 mm2). The right coronary artery was also enlarged preoperatively (13 mm2; controls = 9 mm2), but was normalized after surgery (11 mm2). A linear correlation was found between LV muscle mass and left (r = 0.88, p0.001) and right coronary artery size (r = 0.84, p0.001) as well as between right coronary artery size and mean pulmonary artery pressure (r = 0.56, p0.01). Thus in chronic mitral regurgitation the enlargement of the left and right coronary artery is proportional to the degree of LV hypertrophy. The increase in right coronary artery size is probably the result of right ventricular pressure overload. Postoperatively there is only partial regression of left coronary artery size but normalization of right coronary artery size.

Objective: The aim was to assess the effect of nisoldipine on left ventricular systolic and diastolic function during prolonged myocardial ischaemia. Methods: The left circumflex coronary artery was ligated for 2 h and reperfused for 4 h in 12 calves. The animals were randomised to a control group (n=6) or to treatment with 1.25 mg·h−1 intravenous nisoldipine (n=6) during 2 h of ischaemia. Circulatory support by a ventricular assist device was performed throughout the experiment except for the time of haemodynamic measurements. Regional wall thickening of a normal and an ischaemic left ventricular region was determined using pairs of ultrasonic crystals. Left ventricular pressure was measured by micromanometry. Left ventricular wall thickness and regional wall stiffness at a common preload of 10 mm Hg were calculated using an elastic model with shifting asymptote. Results: Ten animals survived after 6 h. No difference was observed in systolic function between controls and nisoldipine treated animals. Systolic thickening of the ischaemic wall remained depressed 4 h after reperfusion and showed some recovery after dopamine infusion. Ischaemic wall stiffness at a common preload was lower after nisoldipine during ischaemia and reperfusion than in controls. Control wall stiffness remained unchanged during the whole experiment with and without nisoldipine. Diastolic thinning of the ischaemic wall was prevented by nisoldipine during ischaemia and after reperfusion. Conclusions: Prolonged myocardial ischaemia is associated with increased myocardial stiffness of the ischaemic wall. Mechanical unloading can help to bridge the acute phase but cannot prevent postischaemic diastolic dysfunction of the ischaemic wall. Nisoldipine has a beneficial effect on regional diastolic function during ischaemia and reperfusion by decreasing regional wall stiffness and preventing diastolic thinning of the ischaemic wall. Cardiovascular Research 1993;27:531-536

In secondary hypertrophy from chronic pressure or volume overload, or both, systolic as well as diastolic abnormalities of left ventricular (LV) function have been described, but their relation has not been defined. In 58 patients with aortic valve disease (28 with aortic valve stenosis, and 30 with aortic regurgitation) and in 11 control subjects, LV biplane cineangiography was performed simultaneously with LV high-fidelity pressure measurements. LV ejection performance was assessed by ejection fraction, and diastolic function by the time constant of LV pressure decay, the early and late peak filling rates, and the constants of chamber (pressure-volume relation) and myocardial stiffness (stress-strain relation). In the entire cohort (n = 69), ejection fraction was inversely related to the time constant of LV relaxation (r = -0.58, p less than 0.001) and to the constant of myocardial stiffness (r = -0.62, p less than 0.001). Despite preserved systolic contractile function (as evaluated from the ejection fraction-mean systolic stress relation), abnormalities in LV diastolic function were present in 9 of 18 patients with pressure overload and 20 of 22 with volume overload. None of the 58 patients with aortic valve disease had a reduced early peak filling rate, whereas a reduction in late peak filling rate was observed in 3 with aortic stenosis, but in none with aortic regurgitation. This, it appears that abnormalities of relaxation and passive diastolic myocardial stiffness precede alterations in myocardial contractility. Assessment of peak filling rates is not helpful to detect diastolic dysfunction in patients with aortic valve disease.

A recently developed electromechanical precision pipe-cutting tool is being field tested. Its primary applications are to cut and free stuck pipe (tubing or drillpipe) or cut pipe to modify a production completion installation. Cutting pipe in today's complex completions presents many challenges. Testing of this new cutting technology has demonstrated significant advantages over previously used equipment. It is non-ballistic, has a large cutting range for a wide range of metal pipes, provides cut monitoring and success detection. The precision of the cut is facilitated by the tool's internal programming (smart function) which allows for specifying the type of metal to be cut, monitoring the depth of the cut, recognizing the drag and making the appropriate adjustments to complete a cut. The ability to complete multiple precise cuts reduces associated rig time. Its large operating temperature and pressure ratings (20,000 psi), large cutting size range, and portability make possible quick deployment to offshore and land operations. Additional field-demonstrated capabilities include: performs accurate smooth cuts, cuts harder metals with a high chrome content, performs precision cuts for inner pipe cutting, works at any deviation, produces minimum debris, surface system allows application to any wireline, does not require circulation holes for the cutting device, operation deployment is not constrained by chemical issues relate to safety and environment, the cutter's light weight, short shipping length (two sections, each less than 10 feet in length), and compatible portable support equipment allow for quick deployment in a variety of transport modes. This paper includes a case study to illustrate the operating challenges associated with tubing and drillpipe cutting in a variety of conditions and environments.

Clinicians working in the field of congenital and paediatric cardiology have long felt the need for a common diagnostic and therapeutic nomenclature and coding system with which to classify patients of all ages with congenital and acquired cardiac disease. A cohesive and comprehensive system of nomenclature, suitable for setting a global standard for multicentric analysis of outcomes and stratification of risk, has only recently emerged, namely, The International Paediatric and Congenital Cardiac Code. This review, will give an historical perspective on the development of systems of nomenclature in general, and specifically with respect to the diagnosis and treatment of patients with paediatric and congenital cardiac disease. Finally, current and future efforts to merge such systems into the paperless environment of the electronic health or patient record on a global scale are briefly explored.On October 6, 2000, The International Nomenclature Committee for Pediatric and Congenital Heart Disease was established. In January, 2005, the International Nomenclature Committee was constituted in Canada as The International Society for Nomenclature of Paediatric and Congenital Heart Disease. This International Society now has three working groups. The Nomenclature Working Group developed The International Paediatric and Congenital Cardiac Code and will continue to maintain, expand, update, and preserve this International Code. It will also provide ready access to the International Code for the global paediatric and congenital cardiology and cardiac surgery communities, related disciplines, the healthcare industry, and governmental agencies, both electronically and in published form. The Definitions Working Group will write definitions for the terms in the International Paediatric and Congenital Cardiac Code, building on the previously published definitions from the Nomenclature Working Group. The Archiving Working Group, also known as The Congenital Heart Archiving Research Team, will link images and videos to the International Paediatric and Congenital Cardiac Code. The images and videos will be acquired from cardiac morphologic specimens and imaging modalities such as echocardiography, angiography, computerized axial tomography and magnetic resonance imaging, as well as intraoperative images and videos.Efforts are ongoing to expand the usage of The International Paediatric and Congenital Cardiac Code to other areas of global healthcare. Collaborative efforts are underway involving the leadership of The International Nomenclature Committee for Pediatric and Congenital Heart Disease and the representatives of the steering group responsible for the creation of the 11th revision of the International Classification of Diseases, administered by the World Health Organisation. Similar collaborative efforts are underway involving the leadership of The International Nomenclature Committee for Pediatric and Congenital Heart Disease and the International Health Terminology Standards Development Organisation, who are the owners of the Systematized Nomenclature of Medicine or “SNOMED”.The International Paediatric and Congenital Cardiac Code was created by specialists in the field to name and classify paediatric and congenital cardiac disease and its treatment. It is a comprehensive code that can be freely downloaded from the internet (http://www.IPCCC.net) and is already in use worldwide, particularly for international comparisons of outcomes. The goal of this effort is to create strategies for stratification of risk and to improve healthcare for the individual patient. The collaboration with the World Heath Organization, the International Health Terminology Standards Development Organisation, and the healthcare industry, will lead to further enhancement of the International Code, and to its more universal use.

During the process of creation of a bidirectional crossmap between the system emerging, on the one hand, from the initiative sponsored by the Congenital Heart Committees of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons, and on the other hand, from that formulated by the Coding Committee of the European Association for Pediatric Cardiology, the Nomenclature Working Group has successfully created the International Paediatric and Congenital Cardiac Code. As would be expected, during the process of crossmapping it became clear that, for most lesions, the European Pediatric Cardiac Code was more complete in its description of the diagnoses, while the International Congenital Heart Surgery Nomenclature and Database Project was more complete in its description of the procedures. This process of crossmapping exemplifies the efforts of the Nomenclature Working Group to create a comprehensive and all-inclusive international system for the naming of paediatric and congenital cardiac disease, the International Pediatric and Congenital Cardiac Code. Although names and classification for paediatric and congenital cardiac disease will continue to evolve over time, we are now closer than ever to reaching uniform international agreement and standardization. The International Paediatric and Congenital Cardiac Code can be downloaded from the Internet, free of charge, at www.ipccc. net.

The hypoplastic left heart syndrome encompasses a spectrum of cardiac malformations that are characterized by significant underdevelopment of the components of the left heart and the aorta, including the left ventricular cavity and mass. At the severe end of the spectrum is found the combination of aortic and mitral atresia, when the left ventricle can be close to non-existent. At the mild end are the patients with hypoplasia of the aortic and mitral valves, but without intrinsic valvar stenosis or atresia, and milder degrees of left ventricular hypoplasia. Although the majority of the patients are suitable only for functionally univentricular repair, a small minority may be candidates for biventricular repair. The nature of the syndrome was a topic for discussion at the second meeting of the International Working Group for Mapping and Coding of Nomenclatures for Paediatric and Congenital Heart Disease, the Nomenclature Working Group, held in Montreal, Canada, over the period January 17 through 19, 2003. Subsequent to these discussions, the Nomenclature Working Group was able to create a bidirectional crossmap between the nomenclature initially produced jointly on behalf of the European Association for Cardio-Thoracic Surgery and the Society of Thoracic Surgeons, and the alternative nomenclature developed on behalf of the Association for European Paediatric Cardiology. This process is a part of the overall efforts of the Nomenclature Working Group to create a comprehensive and all-inclusive international system of nomenclature for paediatric and congenital cardiac disease, the International Paediatric and Congenital Cardiac Code. In this review, we discuss the evolution of nomenclature and surgical treatment for the spectrum of lesions making up the hypoplastic left heart syndrome and its related malformations. We also present the crossmap of the associated terms for diagnoses and procedures, as recently completed by the Nomenclature Working Group.

The nomenclature and classification of patients with a functionally univentricular heart has been debated for decades. We review here the approach taken for dealing with this group of patients by the International Working Group for Mapping and Coding of Nomenclatures for Paediatric and Congenital Cardiac Disease. We discuss the approach of this Nomenclature Working Group in the context of other historical and contemporary ideas about this topic.

Summary Delineation of bed boundaries is one of the important aspects of petrophysical interpretation. Proper location of bed boundaries plays a key role in log data inversion, especially in resistivity inversion, where the subsurface formation parameters are commonly parameterized into layers of varying thickness and resistivity. Traditionally, the location of bed boundaries is chosen based on the inflection points, maximum change in slope, etc. These algorithms work well for focussed responses and reasonably well for unfocussed responses, but the algorithms fail in presence of noise and in thin-bed regions. In order to overcome these difficulties, we propose an algorithm using Artificial Neural Networks (ANN) for detection of bed boundaries. We demonstrate the applicability of the algorithm on array induction data for a synthetic Oklahoma formation model and a field data from the Gulf of Mexico. The results obtained from the proposed scheme are compared with existing bed boundary

Heart rate changes during determination of coronary flow by parametric imaging may influence the flow measurement. Thus, the question is whether atrial pacing is mandatory for determination of coronary flow reserve (CFR) by this technique. CFR was calculated by digital subtraction angiography (parametric imaging) in 10 patients (8 with coronary artery disease and 2 control subjects) during sinus rhythm and during atrial pacing. Flow measurements were determined in the perfusion region of the left anterior descending and circumflex coronary artery, both at rest and after maximal coronary vasodilation with 10 mg intracoronary papaverine. CFR was defined as coronary flow during hyperemia divided by coronary flow at rest. Spontaneous heart rate was 71 +/- 15 min-1 at baseline, 73 +/- 15 min-1 after papaverine injection and 85 +/- 10 min-1 during atrial pacing. Heart rate variations during coronary arteriography were 4 +/- 3 min-1 at baseline and 5 +/- 4 min-1 after papaverine administration. CFR was 2.61 +/- 1.01 during sinus rhythm and 2.67 +/- 1.05 during atrial pacing. Mean absolute difference in CFR between sinus rhythm and atrial pacing was 0.31 +/- 0.31 (12 +/- 10% of CFR during pacing). Spontaneous heart rate variations during coronary arteriography are not associated with significant changes in CFR. Thus, atrial pacing is not mandatory for the determination of CFR by parametric imaging.

Few would dispute that American mass communi cation dispenses large doses of violence to audiences ever grow ing in size. Two related controversies stem from this fact. One concerns the question of effects and the other the problem of control. An inventory of relevant research is inconclusive about effects, partly because of varying conceptions of what constitutes evidence. A dynamic opinion process leads to con trol efforts. Critics play a vital part in defining discontent. A reciprocal relationship emerges between the public, the critic, and the media. American media respond to controversy and threat of censorship with systems of self-regulation. These grow out of public opinion and are sustained by it in a delicate balance dependent somewhat on developing knowledge of the effects of violence.

Building and expanding on an earlier study by Janowitz, the authors produce new evidence of the neighborhood paper's function as a “catalyst” which helps integrate individuals and groups into the community. They also describe the “communication system” provided by the weekly paper and by discussion of its content.

Objectives. The present study was designed to evaluate the effects of surgical procedure on left ventricular systolic and diastolic function in patients with mitral regurgitation. Background. Left ventricular systolic function has been shown to decline after operation in patients with chronic mitral regurgitation. Methods. Using simultaneous cineangiography and left ventricular micromanometry, we evaluated left ventricular systolic and diastolic function in 14 patients with chronic mitral regurgitation both preoperatively and at an average of 22 months after operation. Eight patients underwent mitral valve reconstruction, and six had a valve replacement with interruption of the chordae tendineae. We compared these patients with 10 control subjects. Results. Preoperatively, patients with mitral regurgitation demonstrated normal global and regional left ventricular systolic function. Peak rate of diastolic filling was increased (p < 0.01), and passive chamber stiffness was decreased, compared with that in control subjects (p < 0.01), and there was normal myocardial stiffness. Postoperatively, systolic and diastolic function returned to normal in patients undergoing mitral valve reconstruction. In contrast, global systolic function was depressed in patients after valve replacement (p < 0.05), with regional dysfunction in the area of papillary muscle attachment (p < 0.01). Diastolic function was depressed in this group, with a prolonged time constant of pressure decay (p < 0.01) and a depressed rate of early diastolic filling and strain rate (p < 0.05). Passive elastic stiffness was within the normal range in all postoperative patients. Conclusions. The type of operation performed to correct chronic mitral regurgitation has an important effect on postoperative left ventricular function. Systolic and diastolic function are preserved after mitral valve reconstruction. Mitral valve replacement with chordal interruption is associated with global and regional systolic dysfunction and early diastolic filling and relaxation abnormalities.

n/a

B. Sh. Singer, O. Fanini, K.-M. Strack, L.A. Tabarovsky, Western Atlas Logging Services, 10201 Westheimer, Houston, TX 77042, USA, and X. Zhang, Electrical Engineering Dept., University of Houston, 4800 Calhoun Rd., Houston, TX 77024, USA Abstract Through casing resistivity measurements confirmed the original concept proposed by Alpin (Ref. 1) and recently revived and improved by Kaufman (Ref. 2) and Vail (Ref. 3). A commercial tool can be used for monitoring producing wells, waterflooding control, and searching for bypassed hydrocarbons in abandoned and active wells. The information on the resistivity of the formation is represented by the second spacial derivative of the casing voltage that is generally small. This makes the evaluation of possible distortions arising from different kinds of casing imperfections important. These imperfections include casing collars, corrosion, perforations, etc. The fact that only low frequencies can be used for the measurement allows us to propose fast and accurate modeling algorithms. Numerical evaluation shows that the distorting effect of casing imperfections is quite moderate. Typically, it does not exceed 10–20% of the measured apparent resistivity. The vertical resolution of the measurements is limited by the spacing between the voltage sensing electrodes. It can deteriorate due to the cement sheath that always exists around the casing. A significant distortion of the measurement occurs near the bottom of the casing. This distortion can reach 50% of the signal. To improve the readings, a simplified inversion algorithm has been developed. The most direct application of the algorithm is the monitoring of the pay zone resistivity. Introduction One of the major requests from the oil and gas industry to logging service companies is the measurement of the formation resistivity behind steel casing. Formation resistivity is the primary indicator of water, gas, and oil saturation. The through casing resistivity (TCR) tool would allow the industry to control pay zone depletion, waterflooding, etc. It would also make it possible to log producing and abandoned wells targeting the hydrocarbons bypassed in the open hole logging operations. Two factors are impeding application of the traditional logging approaches to measurement of formation resistivity behind a steel casing. The first and the major factor is the low resistivity of the casing steel that is typically about 0.2 m. A high magnetic permeability of the steel (40–110) is another obstacle for electrical logging of cased wells. At the frequency of 1 kHz, the skin depth in the steel is less than 0.1 cm; much smaller than the thickness of the casing wall. This means that an electromagnetic field created inside the casing will not penetrate into the formation. To energize the formation and to measure its inductive response. Ref. 4 proposed to saturate the casing with a strong magnetic DC-field. The relative magnetic permeability of a saturated casing equals one. This results in the increase of the frequency threshold. Ref. 5 proposed very low-frequency induction logging measurements so that magnetic saturation could be avoided. A number of authors concentrated their efforts on the development of a TCR tool based on low frequency galvanic energizing of the casing and the formation behind the casing. The concept of evaluating the current leaking from an energized casing into the formation was originated by Alpin (Ref. 1), who proposed a three-electrode apparatus measuring the second difference of the voltage inside the casing. As a practical solution, the concept was not implemented for almost 50 years, mainly due to two circumstances. P. 999

The various effects of melting snow have attracted the attention of engineers and scientists for quite some time. A number of men have made investigations of the phenomena and each has Drought to the subject a viewpoint and approach colored by his past experience and the requirements of the branch of endeavor in which he was engaged. Thus the meteorologist was primarily interested in the effects that bodies of snow might have on the temperature, humidity, and movements of the atmosphere. The geologist was interested in the formation and physiographical effects of glaciers. The hydroelectric, water-supply, and irrigation engineers were interested in the amount of water that would be available for beneficial use in any particular season, or the minimum amount that could be relied upon, in order to properly plan the season's operations and thus get the most beneficial use from such water as would be available.