Pre-procedural pacing bias among transcatheter aortic valves with higher post-procedure pacing rates: evidence from the UK TAVI Registry.

Rates of permanent pacemaker (PPM) implantation following transcatheter aortic valve implantation (TAVI) are higher than following surgery and are dependent on patient factors and valve type. There is an increasing trend towards pre-emptive PPM insertion in patients with significant conduction disease prior to TAVI. We report results from the British Cardiovascular Intervention Society (BCIS) on pre- and post-procedural PPM implantation in the TAVI population. All centres in the United Kingdom performing TAVI are required to submit data on all TAVI procedures to the National database which are then reported annually. During 2015, there were 2373 TAVI procedures in the UK. 22.4% of TAVI patients had a PPM implanted either pre-procedure (including the distant past), or during the in-hospital procedural episode. Of these, 7.9% were pre-procedure and 14.5% post-procedure. Overall PPM rates were Edwards Sapien (13.5%), Medtronic CoreValve (28.2%) and Boston Lotus (42.1%; p < 0.01). Pre-procedure pacing rates were Edwards Sapien (6.0%), Medtronic CoreValve (9.1%) and Boston Lotus (12.3%; p < 0.01). Pre-procedural pacing rates for the Boston Lotus valve have risen year-on-year from 5.8% (2013) to 8.6% (2014) to 12.3% (2015). The UK TAVI Registry demonstrates a pre-procedural permanent pacing bias amongst patients receiving transcatheter valves with higher post-procedure pacing rates. Pre-emptive permanent pacing is likely to be responsible for this difference.

A randomized controlled trial of a walking training with simultaneous cognitive demand (dual-task) in chronic stroke.

BACKGROUND AND PURPOSE: The aim was to evaluate the tolerability of, adherence to and efficacy of a community walking training programme with simultaneous cognitive demand (dual-task) compared to a control walking training programme without cognitive distraction. METHODS: Adult stroke survivors at least 6 months after stroke with a visibly obvious gait abnormality or reduced 2-min walk distance were included in a two-arm parallel randomized controlled trial of complex intervention with blinded assessments. Participants received a 10 week, bi-weekly, 30 min treadmill programme at an aerobic training intensity (55%-85% heart rate maximum), either with or without simultaneous cognitive demands. Outcome was measured at 0, 11 and 22 weeks. The primary assessment involved 2-min walk tests with and without cognitive distraction to investigate the dual-task effect on walking and cognition; secondary results were the Short Form Health Survey 36, EuroQol-5D-5L, the Physical Activity Scale for the Elderly (PASE) and step activity. RESULTS: Fifty stroke patients were included; 43 received allocated training and 45 completed all assessments. The experimental group (n = 26) increased their mean (SD) 2-min walking distance from 90.7 (8.2) to 103.5 (8.2) m, compared with 86.7 (8.5) to 92.8 (8.6) m in the control group, and their PASE score from 74.3 (9.1) to 89.9 (9.4), compared with 94.7 (9.4) to 77.3 (9.9) in the control group. Statistically, only the change in the PASE differed between the groups (P = 0.029), with the dual-task group improving more. There were no differences in other measures. CONCLUSIONS: Walking with specific additional cognitive distraction (dual-task training) might increase activity more over 12 weeks, but the data are not conclusive.

Thyroid hormone receptor beta-1 expression in early breast cancer: a validation study.

PURPOSE: Preliminary data suggest that high expression of the TRß1 tumor suppressor is associated with longer survival among women with early breast cancer. We undertook this study to validate these findings. METHODS: In this prospective cohort study, we analyzed the prognostic significance of TRß1 protein expression in the breast tumors of 796 women who had undergone breast surgery in the Henrietta Banting Breast Cancer database. All women were recruited after undergoing primary surgical therapy at Women's College Hospital (Toronto, ON, Canada) between January 1987 and December 2000. Details regarding patient age at diagnosis, systemic, and local therapies, as well as pathological features of their tumor have been systematically recorded. Clinical outcomes including breast cancer recurrence and death have been updated at least once each year with a median follow-up of 9.6 years (range 0.1-21 years). RESULTS: High TRß1 expression (> 4 on the Allred score) was associated with a longer breast cancer-specific survival with a HR 0.45 (95% CI 0.33-0.61), p < 0.0001 in a univariable Cox regression model. This was maintained in a multivariable model adjusted for age, tumor size, nodal status, chemotherapy, hormone therapy, radiotherapy, surgery, and ER status with a HR of 0.61 (95% CI 0.44-0.85), p = 0.004. CONCLUSIONS: High expression of TRß1 is associated with longer breast cancer-specific survival independent of other prognostic factors. Given that low TRß expression is associated with chemotherapy resistance in-vitro, TRß1 may also serve as a predictive biomarker or even a therapeutic target given the availability of TRß agonists.

Active mode locking of quantum cascade lasers in an external ring cavity.

Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode-locked operation remains a challenge, despite dedicated effort. Here we report the demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents.

Procedural and follow-up outcomes among patients undergoing successful recanalisation of coronary chronic total occlusions using biolimus drug-eluting stents.

This study aimed at evaluating the outcome of Biolimus eluting stent (BES) implantation in the treatment of chronic total coronary occlusions (CTO). We identified patients who underwent successful angioplasty for a CTO lesion with ≥1 BES between June 2008 and March 2012. All patients were followed up for major adverse cardiac events (MACE), which comprised death, non-fatal myocardial infarction (MI), cerebrovascular accident, target vessel revascularization (TVR), target lesion revascularization (TLR) and stent thrombosis. 125 patients underwent successful CTO angioplasty with ≥1 Biolimus-eluting stents. Mean age was 63.8 ± 12.0 years, and 82.4 % were males. Lesion location was right coronary artery (n = 80, 64 %), left anterior descending artery (n = 35, 28 %) and left circumflex artery (n = 10, 8 %). During follow-up of 579 ± 293 days, all cause mortality was n = 8 (6.4 %) patients, non-fatal MI was n = 3 (2.4 %), TVR was n = 3 (2.4 %) and TLR was n = 1 (0.8 %). Overall MACE was, therefore, n = 15 (12 %). BES is safe and effective in treatment of CTO lesions, with a low rate of major adverse cardiovascular events during follow-up.

Rapid passage signals induced by chirped quantum cascade laser radiation: K state dependent-delay effects in the nu2 band of NH3.

In this Letter, a 10 microm quantum cascade laser operating in the intrapulse mode is used observe rapid passage (RP) effects within a 40 cm single-pass gas cell containing low pressures of NH(3). The laser tuning range allows the rotational states J=2 with K=0, 1, and 2 to be probed. We show that the RP structures change as a function of optical density and that the magnitude of the delay in the switch from absorption to emission as a function of increased gas pressure is dependent upon the initial value of K. These measurements are qualitatively well modeled using the Maxwell-Bloch equations.

One-stage tubeless antegrade ureteric stenting: a safe and cost-effective option?

INTRODUCTION: Antegrade insertion of ureteric stent has become an established mode of management of upper tract obstruction secondary to ureteric pathology. It is conventionally performed as a two-stage procedure for various reasons but, more recently, a one-stage approach has been adopted. PATIENTS AND METHODS: We discuss our experience of primary one-stage insertion of antegrade ureteric stent as a safe and cost-effective option for the management of these difficult cases in this retrospective observational case cohort study of patients referred to a radiology department for decompression of obstructed upper tracts. Data were retrieved from case notes and a radiology database for patients undergoing one-stage and two-stage antegrade stenting. It was followed by telephone survey of regional centres about the prevalent local practice for antegrade stenting. Outcome measures like hospital stay, procedural costs, requirement of analgesia/antimicrobials and complication rates were compared for the two approaches. RESULTS: a one-stage approach was found to be suitable in most cases with many advantages over the two-stage approach with comparable or better outcomes at lower costs. Some of the limitations of the study were retrospective data collection, more than one radiologist performing stenting procedures and non-availability of interventional radiologist falsely raising the incidence of two-stage procedures. CONCLUSIONS: In the absence of any clinical contra-indications and subject to availability of an interventional radiologist's support, one-stage antegrade stenting could easily be adopted as a routine approach for the management of benign or malignant ureteric obstruction.

Digital subtraction angiography of the superior mesenteric artery: identifying arterial branches.

This "problem in diagnostic imaging" provides an overview of the technique of digital subtraction angiography. The possibility of artefacts arising from movement subsequent to the taking of the masking image is discussed. It is also important that contrast medium is allowed to backflow into the parent vessel (in this case the aorta) to ensure that there has been filling of the proximal branches of the vessel of interest (in this case the superior mesenteric artery). An accessory middle colic artery is demonstrated. Detection of such variant vessels is important not only to surgeons but also to specialist radiologists carrying out therapeutic embolization.

Successful intra-arterial alteplase infusion is a predictor of 12-month limb survival in patients with lower limb arterial occlusion.

AIM: To determine the factors predicting amputation of the affected lower limb 12 months after thrombolysis for acute arterial occlusion. MATERIALS AND METHODS: The clinical endpoints of 39 patients (24 men, 15 women; average age 69 years) 1 year after catheter-directed thrombolysis with alteplase (mean dose 30 mg, mean duration 24h) for lower limb arterial occlusion (30 native arteries, nine grafts) from January 2001 to June 2005 were assessed. The amputation rate at 12 months was analysed in relation to the thrombolytic outcome, type of vessel occluded, presence or absence of complications, and subsequent requirement for additional surgery on an elective basis using Fischer's exact test. RESULTS: Successful thrombolysis, defined as complete clot dissolution based on angiographic imaging, was achieved in 64.1% of cases (19 native artery, six bypass graft) with a total complication rate of 23% (n=9). The incidence of major haemorrhage was 7.5% (n=3, hypotension and haematemesis, groin haematoma and hypotension, haematemesis). No patient had an intracranial bleed. One year after thrombolysis, 28.2% (n=11) had further surgery (bypass graft, fasciotomy, embolectomy) and the amputation rate was 20.5% (n=8). Statistical analysis showed that the amputation rate was significantly higher for patients with failed compared with successful thrombolysis (p=0.02). The amputation rates did not reach statistical significance in relation to native artery or graft occlusion, presence or absence of complications, and whether or not additional surgery was required. CONCLUSION: Successful thrombolysis was a predictor for limb survival up to 12 months post-thrombolysis regardless of the type of vessel occlusion, presence of complications or additional surgical requirement.

Bimodal electric tissue ablation (BETA) - in-vivo evaluation of the effect of applying direct current before and during radiofrequency ablation of porcine liver.

AIM: To examine the effect of applying increasing amounts of direct current (DC) before and during alternating current radiofrequency ablation of porcine liver. MATERIALS AND METHODS: Using a Radiotherapeutics RF3000 generator, a 9 V AC/DC transformer and a 16 G plain aluminium tube as an electrode, a control group of 24 porcine hepatic radiofrequency ablation zones was compared with 24 zones created using a bimodal electric tissue ablation (BETA) technique in three pigs. All ablations were terminated when tissue impedance rose to greater than 999 Omega or radiofrequency energy input fell below 5 W on three successive measurements taken at 1 min intervals. BETA ablations were performed in two phases: an initial phase of variable duration DC followed by a second phase during which standard radiofrequency ablation was applied simultaneously with DC. During this second phase, radiofrequency power input was regulated by the feedback circuitry of the RF3000 generator according to changes in tissue impedance. The diameters (mm) of each ablation zone were measured by two observers in two planes perpendicular to the plane of needle insertion. The mean short axis diameter of each ablation zone was subjected to statistical analysis. RESULTS: With increased duration of prior application of DC, there was a progressive increase in the diameter of the ablation zone (p<0.001). This effect increased sharply up to 300 s of pre-treatment after which a further increase in diameter occurred, but at a much lesser rate. A maximum ablation zone diameter of 32 mm was produced (control diameters 10-13 mm). CONCLUSION: Applying a 9 V DC to porcine liver in vivo, and continuing this DC application during subsequent radiofrequency ablation, results in larger ablation zone diameters compared with radiofrequency ablation alone.

Measuring psychological consequences of screening: adaptation of the psychological consequences questionnaire into Dutch.

OBJECTIVE: To assess the psychometric properties of a Dutch adaptation of an originally Australian instrument measuring the psychological impact of breast cancer screening. METHODS: The three subscales (emotional, physical, social) of the Psychological Consequences Questionnaire (PCQ) underwent formal linguistic and cultural translation. A total of 524 women under intensive surveillance because of increased breast cancer risk were asked to complete the questionnaire at 2 months prior to screening, at the day of the screening visit preceding the screening, and 1-4 weeks after screening. Acceptability, score distribution, internal consistency, scale structure, responsiveness to change and construct validity were analysed. RESULTS: Response rates were high (98-94%) and there were very few missing answers and non-unique answers. All scales had Cronbach's alphas > 0.70. The physical and social subscale showed ceiling effects. The item-own scale correlations were only slightly higher than the corresponding item-other scale correlations. Factor analysis showed that the assumed three separate subscales were replicated in our study. Pre- and post-screening effect sizes for the emotional scale were larger than for the other two scales. All PCQ scales correlated with the scales of two other psychological measures (p

Disruption of sitting balance after stroke: influence of spoken output.

OBJECTIVES: To identify the extent of dual task interference between cognitive and motor tasks, (cognitive motor interference (CMI)) in sitting balance during recovery from stroke; to compare CMI in sitting balance between stroke and non-stroke groups; and to record any changes to CMI during sitting that correlate with functional recovery. METHOD: 36 patients from stroke rehabilitation settings in three NHS trusts. Healthy control group: 21 older volunteers. Measures of seated postural sway were taken in unsupported sitting positions, alone, or concurrently with either a repetitive utterance task or an oral word category generation task. Outcome measures were variability of sway area, path length of sway, and the number of valid words generated. RESULTS: Stroke patients were generally less stable than controls during unsupported sitting tasks. They showed greater sway during repetitive speech compared with quiet sitting, but did not show increased instability to posture between repetitive speech and word category generation. When compared with controls, stroke patients experienced greater dual task interferences during repetitive utterance but not during word generation. Sway during repetitive speech was negatively correlated with concurrent function on the Barthel ADL index. CONCLUSIONS: The stroke patients showed postural instability and poor word generation skills. The results of this study show that the effort of verbal utterances alone was sufficient to disturb postural control early after stroke, and the extent of this instability correlated with concomitant Barthel ADL function.

Prospective randomized trial of laparoscopic gastrojejunostomy versus duodenal stenting for malignant gastric outflow obstruction.

BACKGROUND: We prospectively compared laparoscopic gastrojejunostomy with duodenal stenting as a means of palliating malignant gastric outflow obstruction. METHODS: A total of 27 patients with malignant gastric outflow obstruction were randomized to either laparoscopic gastrojejunostomy (LGJ) or duodenal stenting (DS) over a 3-year period. RESULTS: Thirteen patients underwent successful LGJ and 10 had successful DS. Eight patients had complications after LGJ, but none had complications after DS. Patients who underwent LGJ had a significant increase in visual analog pain score at day 1 (p = 0.05), and also had a longer hospital stay compared to those who underwent DS (11.4 vs. 5.2 days, p = 0.02). After DS, patients experienced an improvement in physical health at 1 month as measured using the Short Form-36 (SF-36) questionnaire (p < 0.01). There was no change following LGJ. CONCLUSION: Duodenal stenting is a safe means of palliating malignant gastric outflow obstruction. It offers significant advantages for patients compared with minimal-access surgery.

Voice recognition for radiology reporting: is it good enough?

AIM: To compare the efficiency and accuracy of radiology reports generated by voice recognition (VR) against the traditional tape dictation-transcription (DT) method. MATERIALS AND METHODS: Two hundred and twenty previously reported computed radiography (CR) and cross-sectional imaging (CSI) examinations were separately entered into the Radiology Information System (RIS) using both VR and DT. The times taken and errors found in the reports were compared using univariate analyses based upon the sign-test, and a general linear model constructed to examine the mean differences between the two methods. RESULTS: There were significant reductions (p<0.001) in the mean difference in the reporting times using VR compared with DT for the two reporting methods assessed (CR, +67.4; CSI, +122.1s). There was a significant increase in the mean difference in the actual radiologist times using VR compared with DT in the CSI reports; -14.3s, p=0.037 (more experienced user); -13.7s, p=0.014 (less experienced user). There were significantly more total and major errors when using VR compared with DT for CR reports (-0.25 and -0.26, respectively), and in total errors for CSI (-0.75, p<0.001), but no difference in major errors (-0.16, p=0.168). Although there were significantly more errors with VR in the less experienced group of users (mean difference in total errors -0.90, and major errors -0.40, p<0.001), there was no significant difference in the more experienced (p=0.419 and p=0.814, respectively). CONCLUSIONS: VR is a viable reporting method for experienced users, with a quicker overall report production time (despite an increase in the radiologists' time) and a tendency to more errors for inexperienced users.

How to recognize and manage psychological distress in cancer patients.

Psychological distress is common in cancer patients, however, it is often unrecognized and untreated. We aimed to identify barriers to cancer patients expressing their psychological concerns, and to recommend strategies to assist oncologists to elicit, recognize, and manage psychological distress in their patients. Medline, Psychlit, and the Cochrane databases were searched for articles relating to the detection of emotional distress in patients. Patients can provide verbal and non-verbal information about their emotional state. However, many patients may not reveal emotional issues as they believe it is not a doctor's role to help with their emotional concerns. Moreover, patients may normalize or somatize their feelings. Anxiety and depression can mimic physical symptoms of cancer or treatments, and consequently emotional distress may not be detected. Techniques such as active listening, using open questions and emotional words, responding appropriately to patients' emotional cues, and a patient-centred consulting style can assist in detection. Screening tools for psychological distress and patient question prompt sheets administered prior to the consultation can also be useful. In conclusion, the application of basic communication techniques enhances detection of patients' emotional concerns. Training oncologists in these techniques should improve the psychosocial care of cancer patients.

Non-valvular atrial fibrillation and stroke: implications for nursing practice and therapeutics.

Atrial fibrillation (AF) is the most common sustained cardiac rhythm disturbance and is increasing in prevalence due to the ageing of the population, and rates of chronic heart failure. Haemodynamic compromise and thromboembolic events are responsible for significant morbidity and mortality in Australian communities. Non-valvular AF is a significant predictor for both a higher incidence of stroke and increased mortality. Stroke affects approximately 40,000 Australians every year and is Australia's third largest killer after cancer and heart disease. The burden of illness associated with AF, the potential to decrease the risk of stroke and other embolic events by thromboprophylaxis and the implications of this strategy for nursing care and patient education, determine AF as a critical element of nursing practice and research. A review of the literature was undertaken of the CINAHL, Medline, EMBASE and Cochrane Databases from 1966 until September 2002 focussing on management of atrial fibrillation to prevent thrombotic events. This review article presents key elements of this literature review and the implications for nursing practice.

Crystallization of the membrane-containing bacteriophage PRD1 in quartz capillaries by vapour diffusion.

Crystals of bacteriophage PRD1, a virus containing an internal lipid bilayer, have been grown in thin-walled quartz capillary tubes by vapour diffusion as a means of eliminating mechanical handling of the crystals during data collection. It has been found that the addition of polyethylene glycol 20 000 (PEG 20K) to the mother liquor that bathes the crystals allows far higher resolution diffraction intensities to be observed. Growing and treating the crystals in this way has produced a small number of crystals which are particularly amenable to X-ray diffraction analysis.