Guidelines for the peri-operative management of people with cardiac implantable electronic devices: Guidelines from the British Heart Rhythm Society.

This document provides practical guidance for the management of people with cardiac implantable electronic devices who are undergoing surgical intervention. Increasing numbers of people have cardiac device implants including pacemakers, implantable defibrillators and cardiac resynchronisation devices. During surgical procedures, exposure to electromagnetic interference may lead to inappropriate device function including withholding of pacing function or shock therapies. The guideline summarises key aspects of pre-operative assessment protocols to ensure that all people have their device clearly identified and have had appropriate device follow-up pre-operatively. It outlines general measures which can minimise the risk of potentially problematic electromagnetic interference in the surgical environment. It also includes detailed guidance according to the type of device, whether individuals are dependent on the pacing function of the device and the nature of the procedure they are undergoing. People identified as being at significant risk of harmful procedure-related inappropriate device function may require temporary alteration to the device programming. This may be carried out by a trained cardiac physiologist using a device programmer or, in some cases, can be achieved by clinical magnet application. Guidance on the safe use of magnets and emergency situations is included. Common diagnostic procedures and dental interventions are covered. The guidance aims to provide specific and pragmatic advice which can be applied to provide safe and streamlined care for people with cardiac implantable devices.

The SSTARS (STeroids and Stents Against Re-Stenosis) Trial: Different stent alloys and the use of peri-procedural oral corticosteroids to prevent in-segment restenosis after percutaneous coronary intervention.

BACKGROUND: Stent design and technological modifications to allow for anti-proliferative drug elution influence restenosis rates following percutaneous coronary intervention (PCI). We aimed to investigate whether peri-procedural administration of corticosteroids or the use of thinner strut cobalt alloy stents would reduce rates of binary angiographic restenosis (BAR) after PCI. METHODS: This was a two centre, mixed single and double blinded, randomised controlled trial using a factorial design. We compared (a) the use of prednisolone to placebo, starting at least six hours pre-PCI and continued for 28days post-PCI, and (b) cobalt chromium (CoCr) to stainless steel (SS) alloy stents, in patients admitted for PCI. The primary end-point was BAR at six months. RESULTS: 315 patients (359 lesions) were randomly assigned to either placebo (n=145) or prednisolone (n=170) and SS (n=160) or CoCr (n=160). The majority (58%) presented with an ACS, 11% had diabetes and 287 (91%) completed angiographic follow up. BAR occurred in 26 cases in the placebo group (19.7%) versus 31 cases in the prednisolone group (20.0%) respectively, p=1.00. For the comparison between SS and CoCr stents, BAR occurred in 32 patients (21.6%) versus 25 patients (18.0%) respectively, p=0.46. CONCLUSION: Our study showed that treating patients with a moderately high dose of prednisolone for 28days following PCI with BMS did not reduce the incidence of BAR. In addition, we showed no significant reduction in 6month restenosis rates with stents composed of CoCr alloy compared to SS (http://www.isrctn.com/ISRCTN05886349).

Spatial and Temporal Variation in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Numbers in the Yogyakarta Area of Java, Indonesia, With Implications for Wolbachia Releases.

of mosquito vector populations, particularly through Wolbachia endosymbionts. The success of these strategies depends on understanding the dynamics of vector populations. In preparation for Wolbachia releases around Yogyakarta, we have studied Aedes populations in five hamlets. Adult monitoring with BioGent- Sentinel (BG-S) traps indicated that hamlet populations had different dynamics across the year; while there was an increase in Aedes aegypti (L.) and Aedes albopictus (Skuse) numbers in the wet season, species abundance remained relatively stable in some hamlets but changed markedly (>2 fold) in others. Local rainfall a month prior to monitoring partly predicted numbers of Ae. aegypti but not Ae. albopictus. Site differences in population size indicated by BG-S traps were also evident in ovitrap data. Egg or larval collections with ovitraps repeated at the same location suggested spatial autocorrelation (<250 m) in the areas of the hamlets where Ae. aegypti numbers were high. Overall, there was a weak negative association (r<0.43) between Ae. aegypti and Ae. albopictus numbers in ovitraps when averaged across collections. Ae. albopictus numbers in ovitraps and BG-S traps were positively correlated with vegetation around areas where traps were placed, while Ae. aegypti were negatively correlated with this feature. These data inform intervention strategies by defining periods when mosquito densities are high, highlighting the importance of local site characteristics on populations, and suggesting relatively weak interactions between Ae. aegypti and Ae. albopictus. They also indicate local areas within hamlets where consistently high mosquito densities may influence Wolbachia invasions and other interventions.

The dancing heart.

A woman with palliative breast cancer presents with dyspnoea and is noted to have an unusual electrocardiogram, with an alternating electrical axis observed. Subsequent echocardiogram demonstrates the classical findings of a large pericardial effusion causing 'electrical alternans' aptly illustrating why this rare phenomenon occurs.

Spectrum and management of complement immunodeficiencies (excluding hereditary angioedema) across Europe.

INTRODUCTION: Complement immunodeficiencies (excluding hereditary angioedema and mannose binding lectin deficiency) are rare. Published literature consists largely of case reports and small series. We collated data from 18 cities across Europe to provide an overview of primarily homozygous, rather than partial genotypes and their impact and management. METHODS: Patients were recruited through the ESID registry. Clinical and laboratory information was collected onto standardized forms and analyzed using SPSS software. RESULTS: Seventy-seven patients aged 1 to 68 years were identified. 44 % presented in their first decade of life. 29 % had C2 deficiency, defects in 11 other complement factors were found. 50 (65 %) had serious invasive infections. 61 % of Neisseria meningitidis infections occurred in patients with terminal pathway defects, while 74 % of Streptococcus pneumoniae infections occurred in patients with classical pathway defects (p < 0.001). Physicians in the UK were more likely to prescribe antibiotic prophylaxis than colleagues on the Continent for patients with classical pathway defects. After diagnosis, 16 % of patients suffered serious bacterial infections. Age of the patient and use of prophylactic antibiotics were not associated with subsequent infection risk. Inflammatory/autoimmune diseases were not seen in patients with terminal pathway, but in one third of patients classical and alternative pathway defects. CONCLUSION: The clinical phenotypes of specific complement immunodeficiencies vary considerably both in terms of the predominant bacterial pathogen, and the risk and type of auto-inflammatory disease. Appreciation of these phenotypic differences should help both immunologists and other specialists in their diagnosis and management of these rare and complex patients.

Wolbachia infection does not alter attraction of the mosquito Aedes (Stegomyia) aegypti to human odours.

The insect endosymbiont Wolbachia pipientis (Rickettsiales: Rickettsiaceae) is undergoing field trials around the world to determine if it can reduce transmission of dengue virus from the mosquito Stegomyia aegypti to humans. Two different Wolbachia strains have been released to date. The primary effect of the wMel strain is pathogen protection whereby infection with the symbiont limits replication of dengue virus inside the mosquito. A second strain, wMelPop, induces pathogen protection, reduces the adult mosquito lifespan and decreases blood feeding success in mosquitoes after 15 days of age. Here we test whether Wolbachia infection affects mosquito attraction to host odours in adults aged 5 and 15 days. We found no evidence of reduced odour attraction of mosquitoes, even for those infected with the more virulent wMelPop. This bodes well for fitness and competitiveness in the field given that the mosquitoes must find hosts to reproduce for the biocontrol method to succeed.

Reduction of Salmonella enterica on grape tomatoes using microwave heating.

Grape tomatoes were surface inoculated with Salmonella enterica serovars Typhimurium, Senftenburg, Kentucky and Enteritidis and heated for 10, 20, 30, 40 and 50 s using a household microwave oven at two different power levels (medium and high). Following heating, viable counts, temperature measurements and quality measurements were performed on the tomatoes. At high power level, more than 2 log reduction of Salmonella enterica was detected on grape tomatoes after 50 s but the texture were damaged. Three heating treatments, 40 s heating at high power level, 40 and 50 s heating at medium power level, could achieve more than 1.45 log reduction of Salmonella enterica on grape tomatoes, and all the treatments except for 50 s at high power level did not affect the color, pH value and nutritional quality of grape tomato after heating (p>0.05). However, 40 s heating at medium power was the only treatment among the three that did not affect the texture quality of grape tomato. Therefore, it might be a potential way for consumers to use microwave heating at medium power level (700 W) for 40 s to reduce Salmonella population on water immersed grape tomatoes.

Effect of short-term exercise training on aerobic fitness in patients with abdominal aortic aneurysms: a pilot study.

BACKGROUND: Patients with abdominal aortic aneurysms (AAA) represent a high-risk surgical group. Despite medical optimization and radiological stenting interventions, mortality remains high and it is difficult to improve fitness. The aim of this pilot study was to evaluate the effect of a 6 week, supervised exercise programme (30 min continuous moderate intensity cycle ergometry, twice weekly) on anaerobic threshold (AT) in subjects with AAA. METHODS: Thirty participants with an AAA under surveillance were randomized to either the supervised exercise intervention (n=20) or a usual care control group (n=10). AT was measured using cardiopulmonary exercise testing, at baseline (AT1), week 5 (AT2), and week 7 (AT3). The change in AT (AT3-AT1) between the groups was compared using a mixed model ancova, providing the mean effect together with the standard deviation (sd) for individual patient responses to the intervention. The minimum clinically important difference (MCID) was defined as an improvement in AT of 2 ml O(2) kg(-1) min(-1). RESULTS: Of the 30 participants recruited, 17 of 20 (exercise) and eight of 10 (control) completed the study. The AT in the intervention group increased by 10% (equivalent to 1.1 ml O(2) kg(-1) min(-1)) compared with the control (90% confidence interval 4-16%; P=0.007). The sd for the individual patient responses to the intervention was 8%. The estimated number needed to treat (NNT) for benefit was 5 patients. CONCLUSIONS: The small mean benefit was lower than the MCID. However, the marked variability in the individual patient responses revealed that a proportion of patients did benefit clinically, with an estimated NNT of 5.

Reliability of the anaerobic threshold in cardiopulmonary exercise testing of patients with abdominal aortic aneurysms.

Anaerobic threshold (AT), determined by cardiopulmonary exercise testing (CPET), is a well-documented measure of pre-operative fitness, although its reliability in patient populations is uncertain. Our aim was to assess the reliability of AT measurement in patients with abdominal aortic aneurysms. Eighteen patients were recruited. CPET was performed four times over a 6-week period. We examined shifts in the mean AT to evaluate systematic bias with random measurement error assessed using typical within-patient error and intraclass correlation coefficient (ICC, 3,1) statistics. There was no significant or clinically substantial change in mean AT across the tests (p = 0.68). The typical within-patient error expressed as a percentage coefficient of variation was 10% (95% CI, 8-13%), with an ICC of 0.74 (95% CI, 0.55-0.89). We consider the reliability of the AT to be acceptable, supporting its clinical validity and utility as an objective marker of pre-operative fitness in this population.

Acute myocarditis secondary to Campylobacter jejuni enterocolitis.

Myocarditis is a rare condition that can mimic an acute coronary syndrome (ACS). We present the case of a 24-year-old male with Noonan syndrome who presented with a diarrhoeal pro-dromal illness, acute onset chest pain, elevated cardiac biomarkers and an abnormal ECG with ST elevation in the absence of obstructive coronary artery disease. The patient had acute myocarditis secondary to Campylobacter jejuni enterocolitis. Infective myocarditis is most commonly due to a viral infection. Myocarditis is very rarely due to a bacterial infection with only isolated reports of myocarditis induced by Campylobacter jejuni infection. At follow-up he remains well. Myocarditis should be considered in all patients presenting with acute onset chest pain and elevated cardiac biomarkers.

Simultaneous presentation of coronary heart disease in identical twins.

The development of coronary artery disease involves a complex interplay between environmental and genetic factors, with premature coronary artery disease having a strong genetic component. We present the case a pair of monozygotic identical twins presenting near simultaneously with coronary artery disease and identical atherosclerotic lesions despite significant differences in environmental risk factors and being divided geographically by 12,000 miles. This is of enormous importance and not merely curiosity value as it will have implications for the prevention of coronary artery disease, provide an opportunity for the development of new therapeutic strategies, and aid targeted primary prevention through family screening.

Strain rate imaging pre- and post-percutaneous coronary intervention: a potential role in the objective detection of ischaemia in exercise stress echocardiography.

AIMS: To determine the feasibility of strain rate imaging (SRI) in the objective detection of exercise-induced ischaemia. METHODS AND RESULTS: Sixteen patients undergoing elective percutaneous coronary intervention (PCI) underwent treadmill exercise stress echocardiography (ESE) pre- and post-PCI. Measurement of systolic SRI parameters was attempted in all myocardial segments at baseline, peak stress, and in recovery. Segments were divided into those supplied by target (Group 1) and non-target vessels (Group 2). Percutaneous coronary intervention was successful in all patients. In Group 1, there was no significant difference in post-systolic strain rate (SRps) at baseline or at peak stress but there was significantly greater SRps pre-PCI compared with post-PCI at 30 min into recovery (-0.37 +/- 0.53 vs. -0.07 +/- 0.44 s(-1), P = 0.004). There were similar findings with the SRps index [ratio of SRps:peak systolic strain rate (SRsys)]. Group 2 segments did not demonstrate any significant differences in SRI parameters pre- and post-PCI. At peak exercise pre-PCI, Group 1 segments had significantly delayed time to SRsys compared with Group 2 (0.12 +/- 0.05 vs. 0.09 +/- 0.05 s, P = 0.013), a difference that was abolished post-PCI. CONCLUSION: This suggests a potential role for SRI in the objective detection of exercise-induced ischaemia by echocardiography at peak stress and during recovery at the time of improved image quality.

Pre-excited atrial fibrillation triggered by intravenous adenosine: a commonly used drug with potentially life-threatening adverse effects.

Although serious adverse events following adenosine administration are rare, it should only be administered in an environment where continuous ECG monitoring and emergency resuscitation equipment are available. The case report describes the development of pre-excited atrial fibrillation in a 31-year-old woman with Wolff-Parkinson-White syndrome following the administration of adenosine. She had previously been fit and well and was admitted to the coronary care unit with a 2 h history of regular palpitations. A 12-lead ECG showed a narrow QRS complex tachycardia. Carotid sinus massage was unsuccessful in terminating the tachycardia and the patient subsequently received rapid boluses of intravenous adenosine. The cardiac rhythm degenerated into atrial fibrillation with ventricular pre-excitation following 12 mg adenosine.

External validation of established risk adjustment models for procedural complications after percutaneous coronary intervention.

BACKGROUND: Workable risk models for patients undergoing percutaneous coronary intervention (PCI) are needed urgently. OBJECTIVE: To validate two proposed risk adjustment models (Mayo Clinic Risk Score (MC), USA and North West Quality Improvement Programme (NWQIP), UK models) for in-hospital PCI complications on an independent dataset of relatively high risk patients undergoing PCI. SETTING: Tertiary centre in northern England. METHODS: Between September 2002 and August 2006, 5034 consecutive PCI procedures (validation set) were performed on a patient group characterised by a high incidence of acute myocardial infarction (MI; 16.1%) and cardiogenic shock (1.7%). Two external models-the NWQIP model and the MC model-were externally validated. MAIN OUTCOME MEASURE: Major adverse cardiovascular and cerebrovascular events: in-hospital mortality, Q-wave MI, emergency coronary artery bypass grafting and cerebrovascular accidents. RESULTS: An overall in-hospital complication rate of 2% was observed. Multivariate regression analysis identified risk factors for in-hospital complications that were similar to the risk factors identified by the two external models. When fitted to the dataset, both external models had an area under the receiver operating characteristic curve >or=0.85 (c index (95% CI), NWQIP 0.86 (0.82 to 0.9); MC 0.87(0.84 to 0.9)), indicating overall excellent model discrimination and calibration (Hosmer-Lemeshow test, p>0.05). The NWQIP model was accurate in predicting in-hospital complications in different patient subgroups. CONCLUSIONS: Both models were externally validated. Both predictive models yield comparable results that provide excellent model discrimination and calibration when applied to patient groups in a different geographic population other than that in which the original model was developed.

NT-proBNP and the diagnosis of left ventricular systolic dysfunction within two acute NHS trust catchment areas: the initial Teesside experience.

PURPOSE: To evaluate the predictive value of N-terminal pro B-type natiuretic peptide (NT-proBNP) reference cut-off values as diagnostic markers for left ventricular systolic dysfunction (LVSD). STUDY DESIGN: A retrospective study assessing the use of NT-proBNP in the diagnostic algorithm for the investigation of patients with suspected signs and symptoms of LVSD presenting to primary care. RESULTS: A generic NT-proBNP cut-off (150 ng/l) value has similar negative and positive predictive valves, specificity and sensitivity compared to age and sex specific cut-off values. CONCLUSION: When using NT-proBNP as a triage tool for screening patients with signs and symptoms suggestive of LVSD, a simple generic cut-off level is as effective as more complex age sex specific cut-off values.