Supraventricular tachycardia and catheter ablation: Anxiety levels and patient perceptions

Aim: To investigate anxiety levels and patient perception associated with supraventricular tachycardia (SVT); investigate anxiety levels and patient perception pre- and post- radiofrequency catheter ablation (RFCA); and explore any association between anxiety and patient perception with patient age and gender.Design: Follow-up quantitative and qualitative cohort study. 141 patients in a tertiary centre in Scotland who underwent an electrophysiological study and RFCA for atrioventricular nodal re-entrant tachycardia, atrioventricular re-entrant tachycardia or atrial tachycardia between 2009 and 2012 were enrolled. 59 (41.8%) were male; mean age at follow-up was 50 years.Interventions: Follow-up by structured phone questionnaire; mean follow-up period was 14 months. Main outcome measures: Anxiety level and patient perception during index episode, and anxiety level before and after RFCA.Results: During index episode, median patient anxiety, on a scale of 0–10, was 8. Anxiety was not associated with gender (p = 0.07). Patients in the lowest and highest anxiety groups tended to be older (mean 54.5 and 44.4 years respectively) compared with those in the middle 2 groups (mean 34.1 and 35.6 years). There was an association between anxiety and age (p = 0.039). 45 (32.0%) participants thought they were having a heart attack or dying. Before RFCA, median anxiety level was 7. 55 (39.0%) patients were afraid of complications, 21 (14.9%) patients feared being awake during RFCA. After RFCA, median anxiety was 2.5.Conclusions: Anxiety is a common accompaniment to SVT that may lead to greater pre-procedural anxiety. Exploring this link may allow reduction of anxiety via better psychopharmacological intervention, education, and preprocedural counselling

Experimental and numerical investigation of an air-to-water heat pipe-based heat exchanger

An experimental and analytical investigation was conducted on an air-to-water heat exchanger equipped with six wickless heat pipes (thermosyphons) charged with water as the working fluid. The flow pattern consisted of a double pass on the evaporator and condenser sections. The six thermosyphons were all made from carbon steel, measured 2m in length and were installed in a staggered arrangement. The objectives of the reported experimental investigation were to analyse the effect of multiple air passes at different air inlet temperatures (100 to 250°C) and air mass flow rates (0.05 to 0.14kg/s) on the thermal performance of the heat exchanger unit including the heat pipes. The results were compared with a CFD model that assumed the heat pipes were solid rods with a constant conductivity. The conductivity of the pipes was extracted from modifications of correlations available in the literature based around the theory of Thermal Resistance. The results proved to be very accurate within 10% of the experimental values

Cystatin C, a marker for successful aging and glomerular filtration rate, is not influenced by inflammation

Abstract Background. The plasma level of cystatin C is a better marker than plasma creatinine for successful aging. It has been assumed that the advantage of cystatin C is not only due to it being a better marker for glomerular filtration rate (GFR) than creatinine, but also because an inflammatory state of a patient induces a raised cystatin C level. However, the observations of an association between cystatin C level and inflammation stem from large cohort studies. The present work concerns the cystatin C levels and degree of inflammation in longitudinal studies of individual subjects without inflammation, who undergo elective surgery. Methods. Cystatin C, creatinine, and the inflammatory markers CRP, serum amyloid A (SAA), haptoglobin and orosomucoid were measured in plasma samples from 35 patients the day before elective surgery and subsequently during seven consecutive days. Results. Twenty patients had CRP-levels below 1 mg/L before surgery and low levels of the additional inflammatory markers. Surgery caused marked inflammation with high peak values of CRP and SAA on the second day after the operation. The cystatin C level did not change significantly during the observation period and did not correlate significantly with the level of any of the four inflammatory markers. The creatinine level was significantly reduced on the first postoperative day but reached the preoperative level towards the end of the observation period. Conclusion. The inflammatory status of a patient does not influence the role of cystatin C as a marker of successful aging, nor of GFR

270-km ultralong raman fiber laser

We analyze the physical mechanisms limiting optical fiber resonator length and report on the longest ever laser cavity, reaching 270 km, which shows a clearly resolvable mode structure with a width of ~120??Hz and peak separation of ~380Hz in the radio-frequency spectrum

Assessment of resolution and intercenter reproducibility of results of genotyping Staphylococcus aureus by pulsed-field gel electrophoresis of SmaI macrorestriction fragments: a multicenter study

Twenty well-characterized isolates of methicillin-resistant Staphylococcus aureus were used to study the optimal resolution and interlaboratory reproducibility of pulsed-field gel electrophoresis (PFGE) of DNA macrorestriction fragments. Five identical isolates (one PFGE type), 5 isolates that produced related PFGE subtypes, and 10 isolates with unique PFGE patterns were analyzed blindly in 12 different laboratories by in-house protocols. In several laboratories a standardized PFGE protocol with a commercial kit was applied successfully as well. Eight of the centers correctly identified the genetic homogeneity of the identical isolates by both the in-house and standard protocols. Four of 12 laboratories failed to produce interpretable data by the standardized protocol, due to technical problems (primarily plug preparation). With the five rel

Colonial America

The first permanent British settlement in what became the United States was established in 1607, nearly 170 years prior to the American declaration of independence. This chapter examines the economic development of the British North American colonies that became the United States. As it describes, abundant natural resources and scarce labor and capital contributed to the remarkable growth in the size of the colonial economy, and allowed the free white colonial population to enjoy a relatively high standard of living. There was not, however, much improvement over time in living standards. Patterns of factor abundance also played an important role in shaping colonial institutions, encouraging reliance on indentured and enslaved labor as well as the development of representative government. For most of the colonial era, the colonists happily accepted their relationship to Britain. After 1763, however, changes in British policies following the end of the Seven Years War created growing tensions with the colonists and ultimately led to the colonies to declare their independence