Satisfaction rates, function, and return to activity following young adult total hip arthroplasty

Aims

Young adults undergoing total hip arthroplasty (THA) largely have different indications for surgery, preoperative function, and postoperative goals compared to a standard patient group. The aim of our study was to describe young adult THA preoperative function and quality of life, and to assess postoperative satisfaction and compare this with functional outcome measures.

Methods

A retrospective cohort analysis of young adults (aged < 50 years) undergoing THA between May 2018 and May 2023 in a single tertiary centre was undertaken. Median follow-up was 31 months (12 to 61). Oxford Hip Score (OHS) and focus group-designed questionnaires were distributed. Searches identified 244 cases in 225 patients. Those aged aged under 30 years represented 22.7% of the cohort. Developmental dysplasia of the hip (50; 45.5%) and Perthes' disease (15; 13.6%) were the commonest indications for THA.

Results

Preoperatively, of 110 patients, 19 (17.2%) were unable to work before THA, 57 (52%) required opioid analgesia, 51 (46.4%) were reliant upon walking aids, and 70 (63.6%) had sexual activity limited by their pathology. One patient required revision due to instability. Mean OHS was 39 (9 to 48). There was a significant difference between the OHS of cases where THA met expectation, compared with the OHS when it did not (satisfied: 86 (78.2%), OHS: 41.2 (36.1%) vs non-satisfied: 24 (21%), OHS: 31.6; p ≤ 0.001). Only one of the 83 patients (75.5%) who returned to premorbid levels of activity did so after 12 months.

Conclusion

Satisfaction rates of THA in young adults is high, albeit lower than commonly quoted figures. Young adults awaiting THA have poor function with high requirements for mobility aids, analgesia, and difficulties in working and undertaking leisure activities. The OHS provided a useful insight into patient function and was predictive of satisfaction rates, although it did not address the specific demands of young adults undertaking THA. Function at one year postoperatively is a good indication of overall outcomes.

Mechano-electrical interactions and heterogeneities in wild-type and drug-induced long QT syndrome rabbits

BACKGROUND

Electromechanical reciprocity - comprising electro-mechanical (EMC) and mechano-electric coupling (MEC) - provides cardiac adaptation to changing physiological demands. Understanding electromechanical reciprocity and its impact on function and heterogeneity in pathological conditions - such as (drug-induced) acquired long QT syndrome (aLQTS) - might lead to novel insights in arrhythmogenesis. Our aim is to investigate how electrical changes impact on mechanical function (EMC) and vice versa (MEC) under physiological conditions and in aLQTS.

METHODS

To measure regional differences in EMC and MEC in vivo, we used tissue phase mapping cardiac MRI and 24-lead ECG vest in healthy (control) and I_Kr -blocker E-4031-induced aLQTS rabbit hearts. MEC was studied in vivo by acutely increasing cardiac preload, and ex vivo by using voltage optical mapping in beating hearts at different preloads.

RESULTS

In aLQTS, electrical repolarization (heart rate corrected RT-interval, RTn370) was prolonged compared to control (p<0.0001) with increased spatial and temporal RT heterogeneity (p<0.01). Changing electrical function (in aLQTS) resulted in significantly reduced diastolic mechanical function and prolonged contraction duration (EMC), causing increased apico-basal mechanical heterogeneity. Increased preload acutely prolonged RTn370 in both control and aLQTS hearts (MEC). This effect was more pronounced in aLQTS (p<0.0001). Additionally, regional RT-dispersion increased in aLQTS. Motion-correction allowed to determine APD-prolongation in beating aLQTS hearts, but limited motion correction accuracy upon preload-changes prevented a clear analysis of MEC ex vivo.

CONCLUSION

Mechano-induced RT-prolongation and increased heterogeneity were more pronounced in aLQTS than in healthy hearts. Acute MEC effects may play an additional role in LQT-related arrhythmogenesis, warranting further mechanistic investigations.

KEY POINT SUMMARY

Electromechanical reciprocity - comprising excitation-contraction coupling (EMC) and mechano-electric feedback loops (MEC) - is essential for physiological cardiac function. Alterations in electrical and/or mechanical heterogeneity are known to have potentially pro-arrhythmic effects. In this study, we aimed to investigate how electrical changes impact on the mechanical function (EMC) and vice versa (MEC) - both under physiological conditions (control) and in acquired long QT syndrome (aLQTS). We show that changing the electrical function (in aLQTS) results in significantly altered mechanical heterogeneity via EMC and - vice versa - that increasing the preload acutely prolongs repolarization duration and increases electrical heterogeneity, particularly in aLQTS as compared to control. Our results substantiate the hypothesis that LQTS is an 'electro-mechanical' - rather than a 'purely electrical' - disease and suggest that acute MEC effects may play an additional role in LQT-related arrhythmogenesis. Abstract figure legend Electromechanical reciprocity in healthy (control) and acquired long QT syndrome (aLQTS) rabbit hearts. A.-B. Electrical alteration in aLQTS. A. Exemplary ECG traces demonstrating I_Kr -blocker E-4031-induced RT prolongation in aLQTS. B. Visualization of heart rate corrected RTn370 (each color-coded scale includes 20ms) on rabbits' torso in aLQTS compared to control (n = 6 each). C. Electro-mechanical coupling (EMC). Exemplary myocardial longitudinal velocity curve in base (cm/s) during cardiac cycle in control (blue) and aLQTS (red). Indicated are peak amplitudes (AMPsys, AMPdia) and time-to-diastolic peak (TTPdia). D. Mechano-electrical coupling (MEC). Box plots of preload induced changes in repolarization. Comparison between the timepoints baseline (15 sec before increase in preload) and time of the maximal RTn370 increase peak-preload (around 20 sec after NaCl bolus injection). Heart rate corrected RTn370 demonstrates more pronounced RT-changes in aLQTS compared to control (n = 13 each). This article is protected by copyright. All rights reserved.

Transcatheter mitral valve-in-valve implantation: a 10-year single center experience

Background

Transcatheter mitral valve-in-valve (TMVIV) appears a reasonable alternative to surgical redo mitral valve replacement in patients with degenerated mitral prosthesis and high surgical risk with favorable early and mid-terms outcomes. Long-term outcomes are limited by high mortality in a comorbid population.

Purpose

We aimed to evaluate early prosthesis hemodynamic performance and late clinical outcomes following TMVIV.

Methods

All patients who underwent TMVIV for degenerated surgical mitral bioprostheses from 2011 to 2020 in our center were included. Prospectively collected demographic, clinical, procedural, and imaging variables were analyzed. Clinical and echocardiographic outcomes were defined according to Mitral Valve Academic Research Consortium (MVARC) definitions and assessed at 30-day and at the latest follow-up available.

Results

A total of 67 patients were included; mean age 76.9±9.6 years, mean STS score 11.0±6.2%, 53.7% male (n=36). Mechanisms of bioprosthetic failure were mitral stenosis (n=32, 47.8%), mitral regurgitation (n=24, 35.8%), and mixed (n=11, 16.4%). Mean time from mitral valve surgery to TMVIV was 10.2±4.3 years. Access was mostly transapical (n=45; 67.2%), followed by transseptal (n=22; 32.8%). Following the first transseptal procedure in 2016; transseptal access accounted for the majority of procedures (22 of 37 cases, 59.4%).

Technical success was achieved in 65 patients (97.0%). Mean hospitalization was 9.2±10.0 days; shorter with the transseptal as opposed to the transapical approach (6.3±8.1 days versus 11.0±10.5 days, p=0.001). At 30-day echographic follow-up, mean mitral valve gradient was 7.3±2.7 and 1 patient (1.9%) had mitral regurgitation &gt;mild.

At 30-day follow-up, 3 patients had died (4.5%); due to left ventricular outflow tract obstruction (1), heart failure (1), and stroke (1). New pacemakers were required in 2 patients (3.0%) and pacemaker lead dislodgement occurred in 1 patient (1.5%), 4 patients (6.2%) were hospitalized for heart failure. At a median follow-up of 3.8 years [1.7–5.1], 29 patients had died (43.3%), valve thrombosis was found in 6 (8.9%) and endocarditis in 4 patients (6.2%). Mitral valve reintervention was performed in 4 patients (6.2%); redo TMVIV due to valve migration in 1 (1.9%), surgical valve replacement in 1 (1.9%), and delayed redilation with a non-compliant balloon due to underexpansion in 2 patients (3.8%).

Conclusion

TMVIV is associated with acceptable 30-day mitral valve hemodynamics. Long-term mortality remains high in this high-surgical risk comorbid group.

Funding Acknowledgement

Type of funding sources: None.

Electro-mechanical and mechano-electrical interactions in healthy and drug-induced LQTS rabbit hearts

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): German Research Foundation

Background

Electrical and mechanical heterogeneities and their interactions (electro-mechanical and mechano-electrical coupling; EMC / MEC) are essential for normal cardiac function. Alterations in these can result in increased arrhythmia formation.

Purpose

With this study, we aim to investigate EMC and MEC under physiological and pathological conditions to better understand their roles in arrhythmia development.

Methods

Multi-channel ECG and TPM-MRI were used to measure regional differences in EMC in healthy ("control") and IKr-blocker E-4031 induced acute LQTS ("E-4031") rabbit hearts in vivo. MEC was studied in both groups by acutely changing mechanical function (increased preload by 6 ml/kg BW bolus of NaCl).

Results

In acute LQTS hearts (E-4031 10µg/kg bolus + 1µg/(kg*min) iv), cardiac repolarization was markedly prolonged compared to healthy controls, (p &lt; 0.0001; n = 13), with increased QT-dispersion (Max-Min), a marker for regional heterogeneity of repolarization (p &lt; 0.01; n = 13).

Changing electrical function by E-4031 resulted in changes of mechanical features (EMC): in acute LQTS hearts, diastolic longitudinal velocity (Vz) was reduced in all basal (p = 0.003; n = 19) and 4/6 mid segments (p = 0.006; n = 19). Longitudinal diastolic TTP was prolonged significantly in 5/6 basal and 4/6 mid segments by E-4031. These alterations led to an increased apicobasal heterogeneity of longitudinal contraction duration (basal-apical Vz_dia_TTP [ms] 2.9 ± 10.6 vs. 21.1 ± 21.3; p = 0.01; n = 9).

Increased preload acutely prolonged QTc in both "control" and "E-4031" hearts (‘control’ 156.6 ± 11.6 to 198.3 ± 20.3; p &lt; 0.0001 vs. ‘E-4031’ 193.9 ± 19.6 to 256.0 ± 37.5; p &lt; 0.0001; n = 13) (MEC). This effect was more pronounced in "E-4031" acute LQTS hearts than in healthy hearts (Figure 1; delta QTc [ms] ‘control’ 41.6 ± 14.9 vs. ‘E4031’ 62.1 ± 32.1; p &lt; 0.006, n = 13). QT-dispersion (Max-Min) was increased significantly upon mechanical change only in "E-4031" (‘E-4031’ 25.8 ± 5.5 to 32.7 ± 12.3; p &lt; 0.03, n = 13).

Conclusion

E-4031-induced changes in electrical function resulted in marked alterations in mechanical features via EMC. Similarly, acute changes in mechanical function (increased preload) resulted in electrical changes via MEC. Importantly, QT-prolonging effects of acutely increased preload, as well as its effects on regional heterogeneity of repolarization, were more pronounced in E-4031-induced acute LQTS hearts, indicating that cardiac repolarization in LQTS may be more susceptible to acute MEC effects than in healthy hearts. Acute MEC effects may thus play an additional role in LQT-related arrhythmogenesis. Abstract Figure.

Nano-scale morphology of cardiomyocyte t-tubule/sarcoplasmic reticulum junctions revealed by ultra-rapid high-pressure freezing and electron tomography

Detailed knowledge of the ultrastructure of intracellular compartments is a prerequisite for our understanding of how cells function. In cardiac muscle cells, close apposition of transverse (t)-tubule (TT) and sarcoplasmic reticulum (SR) membranes supports stable high-gain excitation-contraction coupling. Here, the fine structure of this key intracellular element is examined in rabbit and mouse ventricular cardiomyocytes, using ultra-rapid high-pressure freezing (HPF, omitting aldehyde fixation) and electron microscopy. 3D electron tomograms were used to quantify the dimensions of TT, terminal cisternae of the SR, and the space between SR and TT membranes (dyadic cleft). In comparison to conventional aldehyde-based chemical sample fixation, HPF-preserved samples of both species show considerably more voluminous SR terminal cisternae, both in absolute dimensions and in terms of junctional SR to TT volume ratio. In rabbit cardiomyocytes, the average dyadic cleft surface area of HPF and chemically fixed myocytes did not differ, but cleft volume was significantly smaller in HPF samples than in conventionally fixed tissue; in murine cardiomyocytes, the dyadic cleft surface area was higher in HPF samples with no difference in cleft volume. In both species, the apposition of the TT and SR membranes in the dyad was more likely to be closer than 10 nm in HPF samples compared to CFD, presumably resulting from avoidance of sample shrinkage associated with conventional fixation techniques. Overall, we provide a note of caution regarding quantitative interpretation of chemically-fixed ultrastructures, and offer novel insight into cardiac TT and SR ultrastructure with relevance for our understanding of cardiac physiology.

Priority allocation of pandemic influenza vaccines in Australia - Recommendations of 3 community juries

BACKGROUND

Pandemic planning has historically been oriented to respond to an influenza virus, with vaccination strategy being a key focus. As the current COVID-19 pandemic plays out, the Australian government is closely monitoring progress towards development of SARS-CoV2 vaccines as a definitive intervention. However, as in any pandemic, initial supply will likely be exceeded by demand due to limited manufacturing output.

METHODS

We convened community juries in three Australian locations in 2019 to assess public acceptability and perceived legitimacy of influenza pandemic vaccination distribution strategies. Preparatory work included literature reviews on pandemic vaccine allocation strategies and on vaccine allocation ethics, and simulation modelling studies. We assumed vaccine would be provided to predefined priority groups. Jurors were then asked to recommend one of two strategies for distributing remaining early doses of vaccine: directly vaccinate people at higher risk of adverse outcomes from influenza; or indirectly protect the general population by vaccinating primary school students, who are most likely to spread infection.

RESULTS

Thirty-four participants of diverse backgrounds and ages were recruited through random digit dialling and topic-blinded social media advertising. Juries heard evidence and arguments supporting different vaccine distribution strategies, and questioned expert presenters. All three community juries supported prioritising school children for influenza vaccination (aiming for indirect protection), one by 10-2 majority and two by consensus. Justifications included that indirect protection benefits more people and is likely to be more publicly acceptable.

CONCLUSIONS

In the context of an influenza pandemic, informed citizens were not opposed to prioritising groups at higher risks of adverse outcomes, but if resources and epidemiological conditions allow, achieving population benefits should be a strategic priority. These insights may inform future SARS-CoV-2 vaccination strategies.

Toward indicators of the performance of US Infrastructures under climate change risks

Built infrastructures are increasingly disrupted by climate-related extreme events. Being able to monitor what climate change implies for US infrastructures is of considerable importance to all levels of decision-makers. A capacity to develop cross-cutting, widely applicable indicators for more than a dozen different kinds of infrastructure, however, is severely limited at present. The development of such indicators must be considered an ongoing activity that will require expansion and refinement. A number of recent consensus reports suggest four priorities for indicators that portray the impacts of climate change, climate-related extreme events, and other driving forces on infrastructure. These are changes in the reliability of infrastructure services and the implications for costs; changes in the resilience of infrastructures to climate and other stresses; impacts due to the interdependencies of infrastructures; and ongoing adaptation in infrastructures.

Hip precautions after primary total hip arthroplasty: a qualitative exploration of clinical reasoning

PURPOSE

Hip precautions are movement restrictions that are often advised following primary total hip arthroplasty (PTHA) for osteoarthritis (OA), but there is limited evidence supporting their effectiveness in preventing dislocation. This study aimed to explore the clinical reasoning behind the continuation and discontinuation of hip precautions following PTHA for OA.

MATERIALS AND METHODS

Semi-structured interviews were conducted with therapists and surgeons at six centres using precautions and six centres not using precautions across secondary or tertiary NHS sites in England. Interviews were transcribed verbatim and thematically analysed.

RESULTS

Interviews were conducted with fourteen surgeons and eighteen therapists. Of these clinicians, eight surgeons and ten therapists routinely advised precautions. Clinicians continued to use precautions to avoid dislocation by creating a boundary to movement, particularly important when dealing with patients who "push" these boundaries. Clinicians discontinued precautions because of a perceived negative impact on patients and the lack of supporting evidence. In the absence of a rise in dislocation rates for these centres, others have now changed practice.

CONCLUSION

This study offers insight into the clinical reasoning behind the continuation and discontinuation of hip precautions following PTHA for OA. The use of precautions remains controversial and further work is required to determine whether or not they should be advised.IMPLICATIONS FOR REHABILITATIONRedesign of future rehabilitation pathways for primary total hip arthroplasty should take into account viewpoints from across the multidisciplinary team to aid decision making.Concern for patient behaviours, dislocation and litigation may be barriers to changing practice for rehabilitation after primary total hip arthroplasty.Clinicians may be discontinuing hip precautions because of known surgical advances, a perceived negative impact on patients and a lack of supporting evidence for historical practice.Individualised rehabilitation considerations are necessary for patients with risk factors that predispose them to dislocation after primary total hip arthroplasty, regardless of whether hip precautions are advised as standard at their given centre.

Low-dose ipilimumab plus nivolumab combined with IL-2 and hyperthermia in cancer patients with advanced disease: exploratory findings of a case series of 131 stage IV cancers - a retrospective study of a single institution

The 3-year overall survival (OS) rate of patients with previously treated or untreated stage III or IV melanoma has by now reached 63% using ipilimumab and nivolumab therapy. However, immune-related adverse events (irAEs) of grade 3 or 4 occurred in 59% of patients leading to discontinuation of therapy in 24.5% of patients and one death. Therapy with checkpoint inhibitors could be safer and more effective in combination with hyperthermia and fever inducing therapies. We conducted a retrospective analysis to test the safety and efficacy of a new combination immune therapy in 131 unselected stage IV solid cancer patients with 23 different histological types of cancer who exhausted all conventional treatments. Treatment consisted of locoregional- and whole-body hyperthermia, individually dose adapted interleukin 2 (IL-2) combined with low-dose ipilimumab (0.3 mg/kg) plus nivolumab (0.5 mg/kg). The objective response rate (ORR) was 31.3%, progression-free survival (PFS) was 10 months, survival probabilities at 6 months was 86.7% (95% CI, 81.0–92.8%), at 9 months was 73.5% (95% CI, 66.2–81.7%), at 12 months was 66.5% (95% CI, 58.6–75.4%), while at 24 months survival was 36.6% (95% CI:28.2%; 47.3%). irAEs of World Health Organization (WHO) Toxicity Scale grade 1, 2, 3, and 4 were observed in 23.66%, 16.03%, 6.11%, and 2.29% of patients, respectively. Our results suggest that the irAEs profile of the combined treatment is safer than that of the established protocols without compromising efficacy.

Geometrical predictors of small virtual neoLVOT size in functional mitral regurgitation

Background

LVOT obstruction is a potentially lethal complication of transcatheter mitral valve replacement (TMVR). An anticipated neoLVOT area of &lt;2cm2 is presumed to imply prohibitive risk. Measurement of the anticipated neoLVOT can be time consuming and requires specialist software to facilitate virtual valve implantation.

Purpose

To determine simple geometrical predictors of prohibitive neoLVOT size.

Methods

165 consecutive, non-calcific FMR patients referred to a transcatheter heart valve program were analysed. Segmentation of the mitral annulus and left heart geometry was performed using CT. Suitability for a default D-shaped TMVR was determined by proprietary annular inclusion criteria. Systolic neoLVOT area was determined via virtual valve implantation of the default TMVR.

Results

Sufficient image data for annular and neoLVOT suitability assessment was available in 152 patients. 105 patients (69%) were suitable for TMVR based on annular measurements. Of these, neoLVOT area was &gt;2cm2 in 88 (84%). Overall, compared to patients not suitable for TMVR (n=64), those suitable had larger ventricles with lower LVEF, and larger annuli (table 1). Using binomial logistic regression involving the variables within table 1, LVESD was the sole statistically significant variable to predict neoLVOT area of &lt;2cm2 (p=0.02). LVESD &lt;48mm had 82% sensitivity and 94% specificity for the presence of prohibitive neoLVOT (figure 1).

Conclusion

Smaller LVESD is a strong predictor of small neoLVOT, and hence LVOT obstruction post default D-shaped TMVR implantation. This simple measure may therefore be used to streamline patient selection for advanced pre-procedural imaging analysis.

Predicting NeoLVOT size &lt;2 cm2

Funding Acknowledgement

Type of funding source: None

Global Research Alliance N2 O chamber methodology guidelines: Recommendations for air sample collection, storage, and analysis

Certain aspects in the collection, handling, storage, and subsequent analysis of discrete air samples from non-steady-state flux chambers are critical to generating accurate and unbiased estimates of nitrous oxide (N₂ O) fluxes. The focus of this paper is on air sample collection and storage in small vials (<12 ml) primarily for gas chromatography (GC) analysis. Sample integrity is assured through following simple procedures including storage under pressure and analysis within a few months of collection. Concurrent storage of standards in an identical manner to samples is recommended and allows the storage period to be reliably extended. In the laboratory, an autosampler is typically used in batch analysis of ∼200 sequentially analyzed samples by GC with an electron capture detector (ECD). Some comparisons are given between GC and alternatives including optical N₂ O detectors that are increasingly being used for high-precision N₂ O measurement. The importance of calibration and traceability of gas standards is discussed, where high-quality standards ensure the most accurate assessment of N₂ O concentration and comparability between laboratories. The calibration allows a consistent and best estimate of flux to be derived.

Minimal patient handling: a faculty of prehospital care consensus statement

This paper outlines the emerging best practice when packaging a prehospital trauma patient while providing spinal immobilisation. The best practice described is based on the recommendations of a consensus meeting held by the Faculty of Pre-Hospital Care, Royal College of Surgeons of Edinburgh, in the West Midlands in April 2012, where the opinion of experienced practitioners from across the prehospital and emergency care community considered the currently available evidence and reviewed current clinical practice. Initial consensus points were then subject to further review and dialogue with stakeholders from the initial meeting. The recommendations drawn from the meeting and subsequent dialogue represent a 'general agreement' to the principles and practices described in the paper. The recommendations will provide guidance for clinical practice and governance alongside other consensus statements from the Faculty of Pre-Hospital Care that seek to address prehospital spinal immobilisation and pelvic immobilisation.

Chromosomal aberrations in peripheral blood lymphocytes exposed to a mixed beam of low energy neutrons and gamma radiation

Cells exposed to thermal neutrons are simultaneously damaged by radiations with high and low linear energy transfer (LET). A question relevant for the assessment of risk of exposure to a mixed beam is whether the biological effect of both radiation types is additive or synergistic. The aim of the present investigation was to calculate whether the high and low LET components of a thermal neutron field interact when damaging cells. Human peripheral blood lymphocytes were exposed to neutrons from the HB11 beam at the Institute for Energy and Transport, Petten, Netherlands, in a 37 °C water phantom at varying depths, where the mix of high and low LET beam components differs. Chromosomal aberrations were analysed and the relative biological effectiveness (RBE) values as well as the expected contributions of protons and photons to the aberration yield were calculated based on a dose response of aberrations in lymphocytes exposed to (60)Co gamma radiation. The RBE for 10 dicentrics per 100 cells was 3 for mixed beam and 7.2 for protons. For 20 dicentrics per 100 cells the respective values were 2.4 and 5.8. Within the limitations of the experimental setup the results indicate that for this endpoint there is no synergism between the high and low LET radiations.

Likely effectiveness of pharmaceutical and non-pharmaceutical interventions for mitigating influenza virus transmission in Mongolia

OBJECTIVE

To assess the likely benefit of the interventions under consideration for use in Mongolia during future influenza pandemics.

METHODS

A stochastic, compartmental patch model of susceptibility, exposure, infection and recovery was constructed to capture the key effects of several interventions--travel restrictions, school closure, generalized social distancing, quarantining of close contacts, treatment of cases with antivirals and prophylaxis of contacts--on the dynamics of influenza epidemics. The likely benefit and optimal timing and duration of each of these interventions were assessed using Latin-hypercube sampling techniques, averaging across many possible transmission and social mixing parameters.

FINDINGS

Timely interventions could substantially alter the time-course and reduce the severity of pandemic influenza in Mongolia. In a moderate pandemic scenario, early social distancing measures decreased the mean attack rate from around 10% to 7-8%. Similarly, in a severe pandemic scenario such measures cut the mean attack rate from approximately 23% to 21%. In both moderate and severe pandemic scenarios, a suite of non-pharmaceutical interventions proved as effective as the targeted use of antivirals. Targeted antiviral campaigns generally appeared more effective in severe pandemic scenarios than in moderate pandemic scenarios.

CONCLUSION

A mathematical model of pandemic influenza transmission in Mongolia indicated that, to be successful, interventions to prevent transmission must be triggered when the first cases are detected in border regions. If social distancing measures are introduced at this stage and implemented over several weeks, they may have a notable mitigating impact. In low-income regions such as Mongolia, social distancing may be more effective than the large-scale use of antivirals.

Patient involvement in blood transfusion safety: patients' and healthcare professionals' perspective

BACKGROUND

Blood transfusion is one of the major areas where serious clinical consequences, even death, related to patient misidentification can occur. In the UK, healthcare professional compliance with pre-transfusion checking procedures which help to prevent misidentification errors is poor. Involving patients at a number of stages in the transfusion pathway could help prevent the occurrence of these incidents.

OBJECTIVES

To investigate patients' willingness to be involved and healthcare professionals' willingness to support patient involvement in pre-transfusion checking behaviours.

MEASURES

A cross-sectional design was employed assessing willingness to participate in pre-transfusion checking behaviours (patient survey) and willingness to support patient involvement (healthcare professional survey) on a scale of 1-7.

PARTICIPANTS

One hundred and ten patients who had received a transfusion aged between 18 and 93 (60 male) and 123 healthcare professionals (doctors, nurses and midwives) involved in giving blood transfusions to patients.

RESULTS

Mean scores for patients' willingness to participate in safety-relevant transfusion behaviours and healthcare professionals' willingness to support patient involvement ranged from 4.96-6.27 to 4.53-6.66, respectively. Both groups perceived it most acceptable for patients to help prevent errors or omissions relating to their hospital identification wristband. Neither prior experience of receiving a blood transfusion nor professional role of healthcare staff had an effect on attitudes towards patient participation.

CONCLUSION

Overall, both patients and healthcare professionals view patient involvement in transfusion-related behaviours quite favourably and appear in agreement regarding the behaviours patients should adopt an active role in. Further work is needed to determine the effectiveness of this approach to improve transfusion safety.

Clinical potential of DAS181 for treatment of parainfluenza-3 infections in transplant recipients

Parainfluenza virus (PIV) infections can cause serious respiratory infections and death in immunocompromised patients. No antiviral agents have proven efficacy against PIV, and therapy generally consists of supportive care. DAS181, a novel sialidase fusion protein that temporarily disables airway epithelial PIV receptors by enzymatic removal of sialic acid moieties, has been shown to inhibit infection with PIV strains in vitro and in an animal model. We describe here the clinical course of 2 immunocompromised patients with PIV-3 infection, one with a history of lung transplantation and the other neutropenic after autologous hematopoietic stem cell transplantation for multiple myeloma. Both patients had substantial clinical improvement in respiratory and systemic symptoms after a 5-day DAS181 treatment course, although the clinical improvement in the autologous stem cell transplantation patient also paralleled neutrophil engraftment.

Comparison between transcatheter and surgical prosthetic valve implantation in patients with severe aortic stenosis and reduced left ventricular ejection fraction

BACKGROUND

Patients with severe aortic stenosis and reduced left ventricular ejection fraction (LVEF) have a poor prognosis with conservative therapy but a high operative mortality when treated surgically. Recently, transcatheter aortic valve implantation (TAVI) has emerged as an alternative to surgical aortic valve replacement (SAVR) for patients considered at high or prohibitive operative risk. The objective of this study was to compare TAVI and SAVR with respect to postoperative recovery of LVEF in patients with severe aortic stenosis and reduced LV systolic function.

METHODS AND RESULTS

Echocardiographic data were prospectively collected before and after the procedure in 200 patients undergoing SAVR and 83 patients undergoing TAVI for severe aortic stenosis (aortic valve area ≤1 cm(2)) with reduced LV systolic function (LVEF ≤50%). TAVI patients were significantly older (81±8 versus 70±10 years; P<0.0001) and had more comorbidities compared with SAVR patients. Despite similar baseline LVEF (34±11% versus 34±10%), TAVI patients had better recovery of LVEF compared with SAVR patients (ΔLVEF, 14±15% versus 7±11%; P=0.005). At the 1-year follow-up, 58% of TAVI patients had a normalization of LVEF (>50%) as opposed to 20% in the SAVR group. On multivariable analysis, female gender (P=0.004), lower LVEF at baseline (P=0.005), absence of atrial fibrillation (P=0.01), TAVI (P=0.007), and larger increase in aortic valve area after the procedure (P=0.01) were independently associated with better recovery of LVEF.

CONCLUSION

In patients with severe aortic stenosis and depressed LV systolic function, TAVI is associated with better LVEF recovery compared with SAVR. TAVI may provide an interesting alternative to SAVR in patients with depressed LV systolic function considered at high surgical risk.