Underage Adolescents' Reactions to Adverts for Beer and Spirit Brands and Associations with Higher Risk Drinking and Susceptibility to Drink: A Cross-Sectional Study in the UK.

AIMS: In the UK, adolescents under the minimum legal purchasing age (<18 years) are aware of a variety of alcohol marketing activities. It is therefore important to examine how such marketing appeals and how it might shape consumption. This study assessed the relationships between positive reactions to alcohol adverts and susceptibility to drink among never drinkers and higher-risk drinking among current drinkers. METHODS: Online cross-sectional survey of 11-17 year olds (n = 2582) in the UK. Adolescents were shown three video alcohol adverts (Fosters Radler/Haig Club Clubman/Smirnoff). Reactions to each were measured by eight scale-items (e.g. 1 = makes [Brand] seem unappealing to 5 = makes [Brand] seem appealing), which were combined into a composite score (coded: positive versus other). Logistic regressions assessed associations between overall positive advert reactions and drinking behaviours. RESULTS: Half of adolescents had overall positive reactions to the Smirnoff (52%) and Fosters (53%) adverts, and a third (34%) had a positive reaction to the Haig Club advert. Across all three adverts, positive reactions were associated with ~1.5 times increased odds of being susceptible to drink among never drinkers. Among current drinkers, positive reactions to the Foster's Radler and Haig Club adverts were associated with around 1.4 times increased odds of being a higher-risk drinker. CONCLUSIONS: These alcohol advertisements commonly appealed to underage adolescents, and these reactions were associated with susceptibility among never drinkers and higher-risk consumption among current drinkers. Regulatory consideration should be given to what messages are permitted in alcohol advertising, including international alternatives (e.g. only factual information).

Impact of a targeted direct marketing price promotion intervention (Buywell) on food-purchasing behaviour by low income consumers: a randomised controlled trial.

BACKGROUND: Price promotions are a promising intervention for encouraging healthier food purchasing. We aimed to assess the impact of a targeted direct marketing price promotion combined with healthy eating advice and recipe suggestions on the purchase of selected healthier foods by low income consumers. METHODS: We conducted a randomised controlled trial (n = 53 367) of a direct marketing price promotion (Buywell) combined with healthy eating advice and recipe suggestions for low income consumers identified as 'less healthy' shoppers. Impact was assessed using electronic point of sale data for UK low income shoppers before, during and after the promotion. RESULTS: The proportion of customers buying promoted products in the intervention month increased by between 1.4% and 2.8% for four of the five products. There was significantly higher uptake in the promotion month (P < 0.001) for the intervention group than would have been expected on the basis of average uptake in the other months. When product switching was examined for semi-skimmed/skimmed milk, a modest increase (1%) was found in the intervention month of customers switching from full-fat to low-fat milk. This represented 8% of customers who previously bought only full-fat milk. The effects were generally not sustained after the promotion period. CONCLUSIONS: Short-term direct marketing price promotions combined with healthy eating advice and recipe suggestions targeted at low income consumers are feasible and can have a modest impact on short-term food-purchasing behaviour, although further approaches are needed to help sustain these changes.

Young people's exposure to point-of-sale tobacco products and promotions.

OBJECTIVES: Point of sale (POS) displays are one of the most important forms of tobacco marketing still permitted in many countries. Reliable methods for measuring exposure to such displays are needed in order to assess their potential impact, particularly on smoking attitudes and uptake among young people. In this study we use a novel method for evaluating POS exposure based on young people's use of retail outlets and recall of tobacco displays and observational data on the characteristics of displays. STUDY DESIGN: Observational audit of retail outlets (n = 96) and school-based pupil survey (n = 1482) in four Scottish communities reflecting different levels of social deprivation and urbanisation, conducted in 2013 before legislation to remove POS displays was implemented in supermarkets. METHODS: Measures were taken of: visibility and placement of tobacco displays; internal and external advertising; display unit size, branding and design; visibility of pack warnings; proximity of tobacco products to products of potential interest to children and young people; pupils' self-reported frequency of visiting retail outlets; and pupils' recall of tobacco displays. Variation in POS exposure across social and demographic groups was assessed. RESULTS: Displays were highly visible within outlets and, in over half the stores, from the public footway outside. Tobacco products were displayed in close proximity to products of interest to children (e.g. confectionery, in 70% of stores). Eighty percent of pupils recalled seeing tobacco displays, with those from deprived areas more likely to recall displays in small shops. When confectioners, tobacconists and newsagents (CTNs) and grocery/convenience stores (two of the outlet types most often visited by young people) were examined separately, average tobacco display unit sizes were significantly larger in those outlets in more deprived areas. CONCLUSIONS: POS displays remain a key vector in most countries for advertising tobacco products, and it is important to develop robust measures of exposure. The data reported in this paper provide a baseline measure for evaluating the efficacy of legislation prohibiting such displays.

Does exposure to cigarette brands increase the likelihood of adolescent e-cigarette use? A cross-sectional study.

OBJECTIVE: To examine the relationship between tobacco cigarette brand recognition, and e-cigarette use in adolescents. DESIGN: Cross-sectional observational study. SETTING: High schools in Scotland. PARTICIPANTS: Questionnaires were administered to pupils in Secondary 2 (S2 mean age: 14.0 years) and Secondary 4 (S4 mean age: 15.9 years) across 4 communities in Scotland. An 86% response rate with a total sample of 1404 pupils was achieved. MAIN OUTCOME MEASURES: Self-reported previous use of e-cigarettes and self-reported intention to try e-cigarettes in the next 6 months. RESULTS: 75% (1029/1377) of respondents had heard of e-cigarettes (69.5% S2, 81.1% S4), and of these, 17.3% (10.6% S2, 24.3% S4 n=1020) had ever tried an e-cigarette. 6.8% (3.7% S2, 10.0% S4 n=1019) reported that they intended to try an e-cigarette in the next 6 months. Recognition of more cigarette brands was associated with greater probability of previous e-cigarette use (OR 1.20, 99% CI 1.05 to 1.38) as was having a best friend who smoked (OR 3.17, 99% CI 1.42 to 7.09). Intention to try e-cigarettes was related to higher cigarette brand recognition (OR 1.41, 99% CI 1.07 to 1.87), hanging around in the street or park more than once a week (OR 3.78, 99% CI 1.93 to 7.39) and living in areas of high tobacco retail density (OR 1.20, 99% CI 1.08 to 1.34). Never having smoked was a protective factor for both future intention to try, and past e-cigarette use (OR 0.07, 99% CI 0.02 to 0.25; and OR 0.10, 99% CI 0.07 to 0.16, respectively). CONCLUSIONS: Higher cigarette brand recognition was associated with increased probability of previous use and of intention to use e-cigarettes. The impact of tobacco control measures such as restricting point-of-sale displays on the uptake of e-cigarettes in young people should be evaluated.

Rapid Holocene thinning of an East Antarctic outlet glacier driven by marine ice sheet instability.

Outlet glaciers grounded on a bed that deepens inland and extends below sea level are potentially vulnerable to 'marine ice sheet instability'. This instability, which may lead to runaway ice loss, has been simulated in models, but its consequences have not been directly observed in geological records. Here we provide new surface-exposure ages from an outlet of the East Antarctic Ice Sheet that reveal rapid glacier thinning occurred approximately 7,000 years ago, in the absence of large environmental changes. Glacier thinning persisted for more than two and a half centuries, resulting in hundreds of metres of ice loss. Numerical simulations indicate that ice surface drawdown accelerated when the otherwise steadily retreating glacier encountered a bedrock trough. Together, the geological reconstruction and numerical simulations suggest that centennial-scale glacier thinning arose from unstable grounding line retreat. Capturing these instability processes in ice sheet models is important for predicting Antarctica's future contribution to sea level change.

E-cigarette marketing in UK stores: an observational audit and retailers' views.

OBJECTIVES: To explore how e-cigarettes are being promoted at point of sale in the UK and how retailers perceive market trends. SETTING: Fixed retail outlets subject to a ban on the display of tobacco products. PARTICIPANTS: Observational audit of all stores selling tobacco products (n=96) in 4 Scottish communities, conducted over 2 waves 12 months apart (2013-2014), and qualitative interviews with small retailers (n=25) in 4 matched communities. PRIMARY AND SECONDARY OUTCOME MEASURES: The audit measured e-cigarette display characteristics, advertising materials and proximity to other products, and differences by area-level disadvantage. Interviews explored retailers' perceptions of e-cigarette market opportunities and risks, and customer responses. RESULTS: The number of e-cigarette point-of-sale display units and number of brands displayed increased between waves. E-cigarettes were displayed close to products of interest to children in 36% of stores. Stores in more affluent areas were less likely to have external e-cigarette advertising than those in deprived areas. Although e-cigarettes delivered high profit margins, retailers were confused by the diversity of brands and products, and uncertain of the sector's viability. Some customers were perceived to purchase e-cigarettes as cessation aids, and others, particularly low-income smokers, as a cheaper adjunct to conventional tobacco. CONCLUSIONS: E-cigarette point-of-sale displays and number of brands displayed increased over 12 months, a potential cause for concern given their lack of regulation. Further scrutiny is needed of the content and effects of such advertising, and the potentially normalising effects of placing e-cigarettes next to products of interest to children.

GM2 gangliosidosis in British Jacob sheep.

GM2 gangliosidosis (Tay-Sachs disease) was diagnosed in 6- to 8-month-old pedigree Jacob lambs from two unrelated flocks presenting clinically with progressive neurological dysfunction of 10 day's to 8 week's duration. Clinical signs included hindlimb ataxia and weakness, recumbency and proprioceptive defects. Histopathological examination of the nervous system identified extensive neuronal cytoplasmic accumulation of material that stained with periodic acid--Schiff and Luxol fast blue. Electron microscopy identified membranous cytoplasmic bodies within the nervous system. Serum biochemistry detected a marked decrease in hexosaminidase A activity in the one lamb tested, when compared with the concentration in age matched controls and genetic analysis identified a mutation in the sheep hexa allele G444R consistent with Tay-Sachs disease in Jacob sheep in North America. The identification of Tay-Sachs disease in British Jacob sheep supports previous evidence that the mutation in North American Jacob sheep originated from imported UK stock.

Development and evaluation of an early detection intervention for mouth cancer using a mass media approach.

BACKGROUND: Scotland has a high incidence of mouth cancer, but public awareness and knowledge are low compared with other cancers. The West of Scotland Cancer Awareness Project sought to increase public awareness and knowledge of mouth cancer and to encourage early detection of symptoms among an at-risk population of people aged over 40 years from lower socio-economic groups using a mass media approach. The media campaign aimed to increase people's feelings of personal risk, while also enhancing feelings of efficacy and control. To achieve this, a testimonial approach (using real people to tell their own stories) was adopted. METHODS: Campaign impact and reach was assessed using in-home interviews with a representative sample of the target population in both the campaign area and controls outside of the target area. Surveys were conducted at three stages: at baseline before the campaign was launched, and at 7 and 12 months thereafter. RESULTS: Awareness of media coverage was higher at both follow-up points in the intervention area than in the control area, the differences largely being accounted for by television advertising. The campaign had a short-term, but not a long-term impact on awareness of the disease and intention to respond to the symptoms targeted by the campaign. Awareness of two of the symptoms featured in the campaign (ulcers and lumps) increased, post-campaign, among the intervention group. CONCLUSIONS: While the study provides evidence for the effectiveness of the self-referral model, further work is needed to assess its ability to build public capacity to respond appropriately to symptoms and to compare the cost-effectiveness of a mass media approach against alternative communication approaches and more conventional mass screening.

Hybrid GaN/organic microstructured light-emitting devices via ink-jet printing.

We report what we believe to be the first use of organic nanostructures for efficient colour conversion of gallium nitride light emitting diodes (LEDs). The particular nanomaterials, based on star-shaped truxene oligofluorenes, offer an attractive alternative to inorganic colloidal quantum dots in the search for novel and functional 'nanophosphors'. The truxenes have been formed into a composite with photoresist and ink-jet printed onto microstructured gallium nitride LEDs, resulting in a demonstrator hybrid microdisplay technology with pixel size approximately 32 microm. The output power density of the hybrid device was measured to be approximately 8.4 mW/cm(2) per pixel at driving current density of 870.8A/cm(2) and the efficiency of colour conversion at drive current of 7 mA was estimated to be approximately 50%.

Precautions to be taken by radiologists and radiographers when prescribing hyoscine-N-butylbromide.

Hyoscine-N-butylbromide (Buscopan, Boehringer Ingelheim) is a widely used antispasmodic in radiological practice. There seems to be no consensus as to best practice within radiology regarding the precautions that need to be taken when prescribing Buscopan. We have performed a thorough review of the available literature and make the following recommendations to those administering Buscopan: (1) enquire whether there is an allergic history; (2) ensure patient literature warns that "in the rare event that following the examination you develop painful, blurred vision in one or both eyes, you must attend hospital immediately for assessment"; (3) warn patients to expect blurred vision and not to drive until this has worn off; (4) remind clinicians that special consideration needs to be given as to the method of investigating patients with cardiac instability, such as those recently admitted with acute coronary syndrome, recurrent cardiac pain at rest, uncontrolled left ventricular failure and recent ventricular arrhythmias.

Sympathetic nerve hyperactivity of essential hypertension is lower in postmenopausal women than men.

Sympathetic activation has been associated with the development and complications of hypertension. While the prevalence of hypertension and its cardiovascular risks in women are found to be less than in men and tend to become similar to men after the menopause, there have been no data on the level of sympathetic activation in postmenopausal women relative to men. Therefore, we planned to find out whether muscle sympathetic nerve hyperactivity of essential hypertension (EHT) in postmenopausal women is different from that in matched men. We quantified muscle sympathetic nerve activity (MSNA) as mean frequency of single units (s-MSNA) and multiunit bursts (b-MSNA) in 21 postmenopausal women with EHT (W-EHT) relative to 21 matched men with EHT (M-EHT), in comparison to two control groups of 21 normal women (W-NC) and 21 men (M-NC), respectively. The EHT groups had greater MSNA indices than NC groups. W-EHT had lower (P<0.05) s-MSNA (63+/-22.7 impulses per 100 cardiac beats) than M-EHT (78+/-11.2 impulses per 100 cardiac beats). W-NC had lower (P<0.05) s-MSNA (53+/-12.4 impulses per 100 cardiac beats) than M-NC (65+/-16.3 impulses per 100 cardiac beats). Similar results were obtained for b-MSNA. Postmenopausal women with EHT had lower level of central sympathetic hyperactivity than men. Similarly, normal postmenopausal women had lower MSNA than men. These findings suggest that postmenopausal women continue to have a lower sympathetic nerve activity than men even after the development of EHT, and that this could have implications for gender-specific management of hypertension.

Integration by self-aligned writing of nanocrystal/epoxy composites on InGaN micro-pixelated light-emitting diodes.

We report on the integration of monodisperse semiconductor nanocrystal (NC) color converters onto gallium nitride ultraviolet micro-pixelated light-emitting diodes ('micro-LEDs'). Integration is achieved in a 'self-aligned' process by forming a nanocomposite of the respective NCs in a photocurable epoxy polymer. Blue, green, yellow and red NC/epoxy blend microstructures have been successfully integrated onto micro-pixelated LEDs by this technique and utilised for color conversion, resulting in a five color emission single chip. Optical output power density of up to about 166 mW/cm2 is measured; spectral emission at 609 nm gives an estimated optical-to-optical conversion as high as 18.2% at 30 mA driving current.

The effect of gender on the sympathetic nerve hyperactivity of essential hypertension.

We planned to determine whether or not there is a difference in the level of muscle sympathetic nerve activity (MSNA) between hypertensive women and hypertensive men. Sympathetic activation of essential hypertension (EHT) has been associated with increased cardiovascular events, which are known to be less likely to occur in women than in men. Normal women have been reported to have less sympathetic nerve activity than men, but no reported data are available regarding gender differences in sympathetic activity in hypertensive subjects. We examined 36 patients with untreated and uncomplicated EHT comprising 18 women and 18 men, and 36 normal controls comprising 18 women and 18 men. MSNA was quantified as the mean frequency of single units and as multiunit bursts using the technique of microneurography. The hypertensive groups had greater sympathetic nerve activity than the control groups. Female hypertensives had lower (P<0.001) single unit hyperactivity (56+/-1.7 impulses/100 cardiac beats) than male hypertensives (72+/-1.7 impulses/100 cardiac beats). Normotensive females had lower (P<0.01) single unit activity (42+/-3.6 impulses/100 cardiac beats) than normotensive males (56+/-4.6 impulses/100 cardiac beats). Similar results were obtained for the frequency of multiunit burst activity. Hypertension in women is associated with a lower level of central sympathetic hyperactivity than in men. It is suggested that this may at least partly explain the observed lower hypertension-related cardiovascular events in women than in men. In addition, the findings may have implications for gender-specific management of hypertension.

Sympathetic nerve hyperactivity in non-diabetic offspring of patients with type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Type 2 diabetes mellitus with hyperinsulinaemia is a state of sympathetic nerve hyperactivity, which can develop subsequently in non-diabetic first-degree offspring of patients with type 2 diabetes. Although both type 2 diabetes and sympathetic activation are major cardiovascular risk factors, the level of sympathetic nerve activity is as yet unknown in offspring of type 2 diabetic patients who are ostensibly normal. We therefore sought to quantify sympathetic nerve activity and its relationship to plasma insulin levels in ostensibly normal offspring of patients with type 2 diabetes, relative to a matched normal control group with no family history of type 2 diabetes. SUBJECTS AND METHODS: In two closely matched groups comprising 23 non-diabetic offspring of type 2 diabetic patients and 23 normal control individuals we measured resting muscle sympathetic nerve activity (MSNA) as the mean frequency of multi-unit bursts of MSNA and single units of MSNA (s-MSNA) with defined vasoconstrictor properties. RESULTS: In offspring of type 2 diabetic patients, the fasting plasma levels of insulin (7.4+/-0.80 microU/ml) and s-MSNA (45+/-3.2 impulses/100 beats) were greater (p<0.009 and p<0.003) than those in control persons (4.6+/-0.76 microU/ml and 32+/-3.1 impulses/100 beats, respectively). MSNA bursts and derived insulin resistance followed similar trends. Sympathetic nerve activity was significantly correlated to insulin levels (p<0.0002) and resistance (p<0.0001) in offspring of type 2 diabetic patients, but not in control subjects. CONCLUSIONS/INTERPRETATION: Sympathetic activation occurred in normal non-diabetic offspring of patients with type 2 diabetes in proportion to their plasma insulin levels. Our data indicate the presence of a mechanistic link between hyperinsulinaemia and sympathetic activation, both of which could play a role in the subsequent development of cardiovascular risk factors.

Methods of the International Tobacco Control (ITC) Four Country Survey.

This paper outlines the design features, data collection methods and analytic strategies of the International Tobacco Control (ITC) Four Country Survey, a prospective study of more than 2000 longitudinal respondents per country with yearly replenishments. This survey possesses unique features that sets it apart among surveys on tobacco use and cessation. One of these features is the use of theory-driven conceptual models. In this paper, however, the focus is on the two key statistical features of the survey: longitudinal and "quasi-experimental" designs. Although it is often possible to address the same scientific questions with a cross-sectional or a longitudinal study, the latter has the major advantage of being able to distinguish changes over time within individuals from differences among people at baseline (that is, differences between age and cohort effects). Furthermore, quasi-experiments, where countries not implementing a given new tobacco control policy act as the control group to which the country implementing such a policy will be compared, provide much stronger evidence than observational studies on the effects of national-level tobacco control policies. In summary, application of rigorous research methods enables this survey to be a rich data resource, not only to evaluate policies, but also to gain new insights into the natural history of smoking cessation, through longitudinal analyses of smoker behaviour.

Effects of the 2003 advertising/promotion ban in the United Kingdom on awareness of tobacco marketing: findings from the International Tobacco Control (ITC) Four Country Survey.

BACKGROUND: In February 2003, a comprehensive ban on tobacco promotion came into effect in the United Kingdom, which prohibited tobacco marketing through print and broadcast media, billboards, the internet, direct mail, product placement, promotions, free gifts, coupons and sponsorships. OBJECTIVE: To investigate the impact of the UK's comprehensive ban on tobacco promotion on adult smokers' awareness of tobacco marketing in the UK relative to Canada, the United States and Australia. DESIGN: A total of 6762 adult smokers participated in two waves of a random digit dialled telephone survey across the four countries. Wave 1 was conducted before the UK ban (October-December 2002) and Wave 2 was conducted after the UK ban (May-September 2003). KEY MEASURES: Awareness of a range of forms of tobacco marketing. RESULTS: Levels of tobacco promotion awareness declined significantly among smokers in the UK after implementation of the advertising ban. Declines in awareness were greater in those channels regulated by the new law and change in awareness of tobacco promotions was much greater in the UK than the other three countries not affected by the ban. At least in the short term, there was no evidence that the law resulted in greater exposure to tobacco promotions in the few media channels not covered by the law. Notwithstanding the apparent success of the UK advertising ban and the controls in other countries, 9-22% of smokers in the four countries still reported noticing things that promoted smoking "often or very often" at Wave 2. CONCLUSIONS: The UK policy to ban tobacco advertising and promotion has significantly reduced exposure to pro-tobacco marketing influences. These findings support the effectiveness of comprehensive bans on advertising and promotion, as included in the Framework Convention on Tobacco Control.

Disparity of autonomic control in type 2 diabetes mellitus.

AIMS/HYPOTHESIS: Acute insulinaemia activates the sympathetic drive in a nonuniform manner. The extent and nature of such activation in type 2 diabetic patients who do not have neuropathy have not yet been addressed despite evidence relating sympathetic activation to cardiovascular risk. We planned to determine the magnitude and extent of the sympathetic drive and its reflex responses in patients with type 2 diabetes and fasting hyperinsulinaemia. METHODS: We measured resting muscle sympathetic nerve activity (MSNA) as the mean frequency of multi-unit bursts and single unit muscle sympathetic nerve activity (s-MSNA) in 17 overweight patients with type 2 diabetes and two matched normal control groups comprising 17 overweight and 16 normal-weight subjects. We also tested the MSNA and s-MSNA responses to cold pressor and isometric hand-grip tests, along with the effect of sympatho-vagal balance on heart period variability. RESULTS: Both MSNA and s-MSNA in the group with type 2 diabetes (66+/-3.5 bursts/100 beats and 78+/-4.5 impulses/100 beats) were greater (at least p<0.0001) than in the overweight control group (42+/-2.6 bursts/100 beats and 48+/-3.4 impulses/100 beats) and normal-weight control group (43+/-6.2 bursts/100 beats and 51+/-7.1 impulses/100 beats), though the three groups had similar reflex responses, baroreflex sensitivity and sympatho-vagal balance controlling the heart period. CONCLUSIONS/INTERPRETATION: The patients with type 2 diabetes had no evidence of impaired reflex or autonomic control of heart period variability at a time when there was central sympathetic activation to the periphery. Furthermore, being overweight itself was not associated with sympathetic activation.

Association of binocular lower visual field impairment, impaired simultaneous perception, disordered visually guided motion and inaccurate saccades in children with cerebral visual dysfunction-a retrospective observational study.

The principal pathways serving higher visual function comprise the dorsal stream and the ventral stream. The dorsal stream runs between the occipital lobes and the parietal lobes and subserves the ability to process the whole visual scene and carry out visually guided movement. The ventral stream runs between the occipital lobes and temporal lobe tissue and primarily subserves visual recognition and memory. These tissues are susceptible to dysfunction in children with brain damage. We report a series of 40 children in whom damage to the brain has led to a common symptom complex affecting vision. Lower visual field loss was frequently elicited. This was associated with impaired ability to make accurate visually guided movement (particularly of the lower limbs) accompanied by impaired simultaneous perception, and in some cases, with inaccurate saccades and in others, impaired perception of movement. These features are consistent with parietal/dorsal stream dysfunction. Difficulty recognising faces and problems with route finding (which are ventral stream functions) were also present in a number of the children. These visual difficulties can be manifest in the presence of normal visual acuity. Recognition of these problems leads to understanding of the child's visual difficulties and facilitates adaptation of curriculum delivery at school.

Does balloon mitral valvuloplasty improve cardiac function? A mechanistic investigation into impact on exercise capacity.

Procedural technical success of balloon mitral valvuloplasty (BMV) is indicated by an increase in valve area and a reduction in transvalvar gradient, but there are conflicting results regarding whether these indicators correlate with subsequent improvements in exercise capacity. We conducted a study to explore the effects of valvuloplasty on cardiac function to gain insight into the mechanisms responsible for the impact on exercise ability. Sixteen patients with mitral stenosis participated in the study and the five who did not proceed to valvuloplasty served as the control group. All patients performed maximal cardiopulmonary exercise tests before and 6 weeks after valvuloplasty (without valvuloplasty in controls). Central haemodynamics including cardiac output were measured non-invasively at rest and peak exercise. At baseline, the cardiopulmonary exercise test results were similar in the two groups. Following valvuloplasty, cardiac output did not alter at rest, but increased significantly at peak exercise (8.7+/-1.7 to 10.5+/-2.1 l min(-1), P<0.01), as did peak cardiac power output (1.88+/-0.55 to 2.28+/-0.74, P<0.05) and cardiac reserve (1.07+/-0.33 to 1.45+/-0.55 watts, P<0.05). Aerobic exercise capacity improved (13.9+/-4.2 to 16.4+/-4.3 ml kg(-1) min(-1), P<0.01) as did exercise duration (354+/-270 to 500+/-266 s, P<0.01). There were no significant changes in the controls. There was a significant correlation between the changes in peak VO(2) and changes in cardiac reserve (r=0.62, P<0.01) but not with changes in resting haemodynamics. These changes did not correlate with changes in peri-procedural mitral valve haemodynamics, despite increases in mitral valve area from 1.05+/-0.16 to 1.74+/-0.4 cm(2) (P<0.0001), accompanied by falls in the transvalvar gradient and pulmonary artery pressure (12.4+/-4.7 to 4.5+/-3 mmHg, and 26.8+/-8.4 to 17.4+/-5.2 mmHg, respectively, all P<0.0001). In conclusion, we found that successful mitral valvuloplasty in our patient cohort led to improved cardiac and physical functional capacity but not resting haemodynamics. Neither indicators of technical success nor resting haemodynamics were very reliable in predicting functional improvement.

Troponin for acute coronary syndromes: has NICE got it right?

The guidelines on the use of glycoprotein IIb/IIIa inhibitors for acute coronary syndromes issued by the National Institute for Clinical Excellence (NICE) recommend that blood troponin is used to identify patients who might benefit from therapy. There are, however, a number of circumstances in which troponin results may be misleading. Firstly, the trials which comprise the evidence base for the therapeutic effect were only based on patients with documented coronary artery disease. Secondly, troponin is elevated in patients with heart failure and concentrations fall with appropriate treatment. Thirdly, there is no internationally accepted standard for troponin, and there are therefore important differences at the 'cut-off' values between the methods of different manufacturers. Fourthly, immunoassays suffer from interfering antibodies and at least 17 case reports have been published outlining false positive tests. It is important that the shortfalls of troponin tests in the diagnosis of acute coronary syndromes are widely recognized.