Too Much Too Little: Clarifying the Relationship Between Maternal Iodine Intake and Neurodevelopmental Outcomes

BACKGROUND

In 2009, the Australian government mandated the fortification of bread salt with iodine. In 2010, pregnant and lactating women were also advised to take an iodine-containing supplement. Our assessment of this policy in an iodine-sufficient population showed that children whose mothers were in the highest and lowest quartiles of iodine intake performed more poorly on early childhood tests of cognition and language than those in the second quartile. However, we did not quantify the iodine intake associated with optimal neurodevelopment.

OBJECTIVES

The aim was to establish the iodine intake range in pregnancy associated with optimal child neurodevelopment.

METHODS

A prospective cohort study of pregnant women and their young children (n = 699). Iodine intake was assessed by a validated food frequency questionnaire at 16 and 28 wk of gestation. Child neurodevelopment at 18 mo of age was measured using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). The relationship between average iodine intake during pregnancy and child neurodevelopment was assessed using linear regression with fractional polynomials and adjustment for confounders.

RESULTS

Mean (SD) iodine intake was similar at study entry and 28 wk, 308 (120) μg/d, with 82% of women taking iodine supplements at study entry. The relationship between iodine intake during pregnancy and Bayley-III cognitive and language scores was curvilinear (P = 0.001 and P = 0.004, respectively), with the lowest Bayley-III scores observed at lower and higher iodine intakes. The inflection point that drove the association between lower iodine intake in pregnancy and poorer child neurodevelopment scores was around 185 μg/d; for the higher pregnancy iodine intakes, language and cognitive scores were negatively affected from ∼350 μg/d to 370 μg/d, respectively. Higher iodine intakes were being driven by supplement use.

CONCLUSIONS

Targeted, not blanket, iodine supplementation may be needed for pregnant women with low-iodine intake from food.

Dispensing of psychotropic medications to Australian children and adolescents before and during the COVID-19 pandemic, 2013-2021: a retrospective cohort study

OBJECTIVE

To determine longitudinal patterns of dispensing of antidepressant, anxiolytic, antipsychotic, psychostimulant, and hypnotic/sedative medications to children and adolescents in Australia during 2013-2021.

DESIGN

Retrospective cohort study; analysis of 10% random sample of Pharmaceutical Benefits Scheme (PBS) dispensing data.

PARTICIPANTS, SETTING

People aged 18 years or younger dispensed PBS-subsidised psychotropic medications in Australia, 2013-2021.

MAIN OUTCOME MEASURES

Population prevalence of dispensing of psychotropic medications to children and adolescents, by psychotropic class, gender, and age group (0-6, 7-12, 13-18 years).

RESULTS

The overall prevalence of psychotropic dispensing to children and adolescents was 33.8 per 1000 boys and 25.2 per 1000 girls in 2013, and 60.0 per 1000 boys and 48.3 per 1000 girls in 2021. The prevalence of psychotropic polypharmacy was 5.4 per 1000 boys and 3.7 per 1000 girls in 2013, and 10.4 per 1000 boys and 8.3 per 1000 girls in 2021. Prevalent dispensing during 2021 was highest for psychostimulants (boys, 44.0 per 1000; girls, 17.4 per 1000) and antidepressants (boys, 20.4 per 1000; girls, 33.8 per 1000). During 2021, the prevalence of dispensing was higher than predicted by extrapolation of 2013-2019 data for many classes, including antidepressants (boys: +6.1%; 95% CI, 1.1-11.1%; girls: +22.2%; 95% CI, 17.4-26.9%), and psychostimulants (boys: +14.5%; 95% CI, 8.0-21.1%; girls: +27.7%; 95% CI, 18.9-36.6%). The increases were greatest for girls aged 13-18 years (antidepressants: +20.3%; 95% CI, 16.9-23.7%; psychostimulants: +39.0%; 95% CI, 27.9-50.0%).

CONCLUSIONS

The prevalence of both psychotropic dispensing and psychotropic polypharmacy for children and adolescents were twice as high in 2021 as in 2013. The reasons and appropriateness of the marked increases in psychotropic dispensing during the COVID-19 pandemic, particularly to adolescent girls, should be investigated.

Acute hemodynamic response of epicardial and endocardial cardiac resynchronization therapy, His bundle pacing and left bundle branch pacing

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Medtronic

Background / Introduction

Endocardial pacing and conduction system pacing are emerging as alternative methods to deliver cardiac resynchronization therapy (CRT) and have been shown to achieve superior acute hemodynamic response (AHR) compared to conventional epicardial pacing. However, a direct comparison of all the methods of delivering CRT has not yet been performed.

Purpose

To directly compare the AHR of conventional CRT (BiV Epi), endocardial pacing (BiV Endo), His bundle pacing (HBP) and left bundle branch pacing (LBBP) during a temporary CRT study.

Methods

4 patients underwent a temporary CRT and hemodynamic study. Temporary pacing was achieved using quadripolar catheters in the right atrium and coronary sinus, and roving decapolar catheters in the right ventricle (RV) and left ventricle (LV) via retrograde aortic access. Hemodynamic assessment was performed with a PressureWire X (Abbott, CA, USA) in the LV cavity. AHR was calculated as the percentage improvement in LV dP/dtmax from baseline AAI or RV pacing (if underlying complete heart block).

Results

The patients had a mean age of 67.5 ±5.8 years and all had non-ischemic cardiomyopathy with severe LV impairment (mean ejection fraction 22.5 ±7.4%). 3 patients had left bundle branch block and 1 patient had complete heart block with an RV paced rhythm (mean QRS duration 157 ±24 ms). All methods of delivering CRT achieved a mean AHR of >10%, which is considered clinically significant and is predictive of LV remodelling at 6 months. Mean AHR during BiV Epi pacing was 12.6 ±5.0%. There was a trend towards higher AHR for BiV Endo pacing (23.6 ±7.6%), HBP (17.4 ± 9.5%) and LBBP (16.1 ±7.8%) as shown in figure 1, however there was no significant difference between groups on one-way analysis of variance (p = 0.348).

Conclusions

All methods of delivering CRT achieved an AHR >10%. The AHR during BiV Endo pacing, HBP and LBBP was higher than for BiV Epi pacing, but this did not reach statistical significance. Further investigation with larger studies is required to determine which method of delivering CRT achieves the best hemodynamic response.

Figure 1. Box plot of acute hemodynamic response (AHR) for conventional cardiac resynchronization therapy (BiV Epi), endocardial pacing (BiV Endo), His bundle pacing (HBP) and left bundle branch pacing (LBBP). Data displayed as median (solid line), mean (+), 1st and 3rd quartiles (box) and minimum and maximum values (whiskers). Abstract Figure 1

Assessing survival and re-hospitalisation following transvenous lead extraction in cardiac resynchronisation therapy devices depending on reimplantation timing: a propensity score matched analysis

Funding Acknowledgements

Type of funding sources: None.

Background

 Among patients undergoing transvenous lead extraction (TLE), differences in complication rate and 1-year mortality has been explored in patients with cardiac resynchronisation therapy (CRT) devices.  Longer term outcomes and the influence of timing of reimplantation of device, with respect to rehospitalisation and longer-term mortality is poorly understood. 

Purpose

 The purpose of this study was to evaluate whether early reimplantation following TLE in patients with CRT devices influenced survival and rehospitalisation.

Methods

 Clinical data from consecutive patients undergoing TLE in the reference centre between the years 2000 to 2019 were prospectively collected.  Patients surviving to discharge who were re-implanted with the same device were included. The cohort was split depending on whether or not they had a CRT device at time of explant.  The association between TLE in CRT patients and all-cause mortality and re-hospitalisation was assessed by Kaplan Meier estimates in a 1:1 propensity-score matched cohort, with a calliper of 0.10.  Early reimplantation was defined as reimplantation within 7 days of TLE, and late reimplantation as reimplantation after greater than 7 days of TLE.

Results

 Of 1005 patients included in the analysis, 285 (25%) had a CRT device.  After matching, 192 CRT patients were compared with 192 non-CRT patients.  Propensity scores were calculated using 39 baseline characteristics, including age, gender, co-morbidities, TLE indication, left ventricular ejection fraction, baseline creatinine and technical extraction data.  Mean follow up was 53.5 ± 38.3 months, mean age at explant was 67.7 ± 12.1 years, 83.3% were male and 54.4% had an infective indication for TLE.  In the matched cohort, there was no significant difference between the CRT and non-CRT group with respect to long-term mortality (hazard ratio [HR] = 1.01, 95% confidence interval [CI] [0.74-1.39], p = 0.093) or rehospitalisation (HR = 1.2 [0.87-1.66], p = 0.265).  A similar proportion of patients were reimplanted within 7 days in the CRT and non-CRT groups (59.4% vs 61.5%, p = 0.754).  In the matched non-CRT group, late reimplantation was associated with similar mortality to early reimplantation (HR = 1.33 [0.86-2.05], p = 0.208) and rehospitalisation (HR = 0.88 [0.53-1.45], p = 0.603).  In the matched CRT group, late reimplantation was associated with higher mortality (HR = 1.64 [1.04-2.57], p = 0.032) and rehospitalisation (HR = 1.57 [1.00-2.46], p = 0.049] (see figure).

Conclusion

  In this closely matched population, TLE in CRT patients resulted in similar long-term outcomes compared with non-CRT patients.  Early reimplantation post CRT explant was associated with reduced long-term mortality and rehospitalisation.  This suggests a longer duration without biventricular pacing post TLE may induce negative reverse-remodelling and should be avoided in a CRT population. Abstract Figure. Kaplan-Meier survival curves

Long-term survival following transvenous lead extraction: importance of indication and comorbidities

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction: 

The significant rise in cardiac implantable electronic devices (CIED) has been paralleled by an increase in the number of procedures required for the removal of such devices and their associated leads.  High procedural success rates with low rates of major in hospital complications is well recognised.  Longer term mortality following transvenous lead extraction (TLE) is less well characterised. Long term outcomes are important as they should inform the decision making and consent process, especially in non-infected cases where there may not be a class I indication for lead removal. 

Purpose

 The purpose of this study was to evaluate the factors influencing survival in patients undergoing TLE depending on extraction indication.

Methods

 Clinical data from consecutive patients undergoing TLE in the reference centre between the years 2000 to 2019 were prospectively collected.  Only patients surviving to discharge were included. The total cohort was divided into groups depending on whether there was an infective or non-infective indication for TLE.  We evaluated the association of demographic, clinical, device related and procedure-related factors on mortality.

Results

 A total of 1151 patients were included in the analysis.  632 (54.9%) and 519 patients (45.1%) were for infective and non-infective indications respectively. Analysis of long-term outcomes on the total cohort (mean 66-month follow-up) revealed a mortality of 34.1% (392 deaths).  A higher proportion of patients died in the infection vs the non-infection group (38.6% vs 28.5%, p < 0.001).  Local infection (hazard ratio [HR] = 1.4, 95% confidence interval [CI] [1.12-1.75]) was associated with similar long-term mortality risk as systemic infection (HR = 1.3, CI[0.99-1.72]). Multivariate analysis demonstrated increased risk of mortality with higher age (HR = 1.05, CI[1.04-1.07]), eGFR < 60ml/min/1.73m2 (HR = 1.55, CI[11.22-1.97]), higher cumulative co-morbidity burden (HR = 1.15, CI [1.06-1.23], and reduced risk per percentage increase in LVEF (HR = 0.98, CI[0.96-1.00]). Kaplan-Meier survival analysis demonstrated statistically worse prognosis in patients with a higher number of leads extracted and increasing co-morbidities.

Conclusion

  Long-term mortality for patients undergoing TLE remains high. Consensus guidelines recommend evaluating risk for major complications when determining whether to proceed with TLE. This study suggests assessing longer-term outcomes when considering TLE, particularly for non-infective indications. Abstract Figure.

Association of Poor Postnatal Growth with Neurodevelopmental Impairment in Infancy and Childhood: Comparing the Fetus and the Healthy Preterm Infant References

OBJECTIVES

To compare the classification of preterm postnatal poor growth using healthy preterm vs fetal growth references and to examine associations with neurodevelopmental impairment in infancy and childhood.

STUDY DESIGN

We included 613 infants born at <33 weeks of gestation. Using the INTERGROWTH-21^st (healthy-preterm growth) reference and the Fenton and Olsen (fetal growth) references, we classified poor growth as a decline in z-score from birth to term-equivalent >0.8 SD (weight), >1 SD (head), and >2 SD (length). We used generalized estimating equations to estimate aOR for neurodevelopmental impairment at 18 months and 7 years of corrected age, comparing infants with and without poor growth by each reference, accounting for multiple births and covariates.

RESULTS

The prevalence of poor growth was higher with INTERGROWTH-21^st than with fetal references for all measurements. Agreement was higher between the Fenton and Olsen (fetal) growth references (0.72-0.81) than between INTERGROWTH-21^st and fetal references (0.41-0.59). Poor growth by fetal references (but not by INTERGROWTH-21^st) was associated with low neurodevelopmental scores in infancy and childhood. Poor weight gain using the Fenton reference was associated with 18-month Mental Developmental Index <85 (aOR 1.6, 95%CI: 1.1, 2.4) whereas poor weight gain by the INTERGROWTH-21^st reference was not (aOR 1.0, 95%CI: 0.6, 1.7). Poor linear growth by the Olsen reference, but not INTERGROWTH-21^st, was associated with 7-year verbal intelligence quotient <70 (aOR 3.5, 95%CI: 1.1, 12.7).

CONCLUSIONS

Poor neonatal growth categorized using fetal references showed stronger associations with long term neurodevelopment than poor growth categorized using the INTERGROWTH-21^st standards.

P532Endocardial pacing is less arrhythmogenic than conventional epicardial pacing when pacing in proximity to scar in patients with ischemic heart failure

Funding Acknowledgements

WT 203148/Z/16/Z; MR/N011007/1; RE/08/003; PG/15/91/31812; PG/16/81/32441

Background

Endocardial pacing has been shown to improve response to cardiac

resynchronization therapy (CRT) in comparison to conventional epicardial pacing and the

physiological activation, endocardium to epicardium, is proposed to make it less arrhythmogenic.

However, the relative arrhythmic risk of endocardial and epicardial pacing has not been

systematically investigated. Pacing in proximity to scar increases susceptibility to arrhythmogenesis

during epicardial pacing. Whether this is also the case during endocardial pacing is currently

unknown.

Purpose

We investigate 1) whether endocardial pacing is less arrhythmogenic than epicardial

pacing, 2) whether pacing location relative to scar plays a role in arrhythmogenesis during

endocardial pacing, and 3) whether these findings could be explained by the direction of the

transmural action potential duration (APD) gradient.

Methods

We used computational models of ischemic heart failure and patient-specific (n = 24) left ventricular anatomy and scar morphology to simulate repolarization during endocardial and

epicardial pacing. Pacing locations were selected 0.2-3.5cm from a scar. We ran simulations with a

20ms transmural APD gradient, as found in heart failure, from the epicardium to endocardium

(physiological) and with this gradient inverted. We computed the volume of high

(&gt;3ms/mm) repolarization gradients (HRG) within 1cm around a scar, as a surrogate for arrhythmia

risk, and analysed these with ANOVA and Tukey-Kramer post-hoc tests.

Results

Simulations with a physiological APD gradient predict that endocardial pacing creates a

smaller (34%) volume of HRG around (1cm) a scar compared to epicardial pacing when

pacing 0.2cm from scar (Figure 1-A). The volume of HRG decreases (P &lt; 0.05) with distance

from scar for epicardial pacing but not endocardial pacing (Figure 1-A). Inverting the

transmural APD gradient, inverts the trend observed with a physiological gradient. In this case, the

volume of HRG is unaffected by pacing location during epicardial pacing, whereas it decreases (19%)

with the distance from scar for endocardial pacing. This is illustrated

in the regions highlighted in yellow in Figure 1 for endocardial pacing at 0.2 and 3.5cm from a scar

with a physiological (B) and an inverted (C) gradient.

Conclusions

Endocardial pacing is less arrhythmogenic (purpose 1) than conventional epicardial

pacing when pacing in proximity to scar and is also less susceptible to pacing location relative to scar

(purpose 2). The direction of the transmural APD gradient offers a mechanistic explanation for

reduced susceptibility to arrhythmogenesis during endocardial pacing compared to epicardial pacing

(purpose 3). Endocardial pacing is an attractive alternative to conventional epicardial pacing in

patients with scar, as it allows pacing in proximity to scar while avoiding increasing arrhythmogenic

risk in patients with ischemic heart failure.

Abstract Figure.

0038 The Effects of Morning Blue Light Therapy on Insomnia Severity and PTSD Symptoms in a Clinical Sample

Introduction

Individuals with Post Traumatic Stress Disorder (PTSD) often present with insomnia, which may exacerbate other symptoms of the disorder. Morning Blue Light Therapy (BLT) can regulate circadian rhythms and may even improve sleep and mood in individuals with major depressive disorder. However, it is unclear whether morning BLT could also be an effective treatment for the insomnia associated with PTSD. We investigated whether 6 weeks of daily morning BLT would improve insomnia severity and symptom presentation in individuals with PTSD in comparison to a placebo condition of amber light (ALT). We hypothesized that changes in insomnia severity would correlate with improvement in PSTD symptom severity.

Methods

Forty-one participants with a clinical diagnosis of PTSD were randomized to receive 6 weeks of either daily morning BLT (n=22) or ALT (n=19). Insomnia and PTSD symptom severity were evaluated at pre- and post-treatment using the Insomnia Severity Index (ISI) and the Clinician-Administered PTSD Scale (CAPS) for DSM-5, respectively.

Results

Both groups showed a significant decrease in their PTSD symptom severity (p&lt;0.001) and insomnia severity (p&lt;0.001) over the 6-week treatment period. However, improvement in insomnia severity significantly predicted improvements in PTSD symptom severity for the BLT group only (BLT: r =0.542, p=0.009; ALT: r=-0.095, p=0.699). The difference between the two correlation coefficients was significant (Z=-2.07, p=0.039).

Conclusion

The results suggest that morning BLT may be effective in improving PTSD symptoms by regulating the circadian rhythm and improving sleep. While ALT also led to improved PTSD symptom severity, it appears that those changes cannot be explained by improved sleep and may have other underlying mechanisms (e.g., placebo effect). Morning BLT may be a promising adjunctive method to bolster current treatment approaches for PTSD. Because of its ease of administration, it could be easily added to ongoing treatment as usual. This approach warrants further research.

Support

US Army Medical Research and Materiel Command: W81XWH-14-1-0570

0081 Habitual Sleep Duration is Negatively Correlated with Emotional Reactivity within the Rostral Anterior Cingulate Cortex in Individuals with PTSD

Introduction

Sleep difficulties, such as insomnia, are highly prevalent in individuals with Post-Traumatic Stress Disorder (PTSD). However, sleep deprivation can also increase emotional reactivity to positive (as well as negative) stimuli. While the effects of sleep loss on emotional perception healthy individuals has been documented, it remains unclear how lack of sleep in individuals with PTSD may affect their emotional reactivity to positive stimuli. We hypothesized that lower habitual sleep duration would be associated with greater functional brain activation changes in response to subliminally presented happy faces in brain areas of the reward network, such as the rostral anterior cingulate cortex (rACC).

Methods

Thirty-nine individuals with DSM-5 confirmed PTSD were administered the Pittsburgh Sleep Quality Index (PSQI) as a measure of their average nightly sleep duration over the past month. Participants then underwent fMRI imagining while viewing subliminal presentations of faces displaying happiness, using a backward masked facial affect paradigm to minimize conscious awareness of the expressed emotion. Brain activation to masked happy expressions was regressed against sleep duration in SPM12.

Results

There was a negative correlation between habitual sleep duration and activation within the rACC in response to the masked happy faces (x=14,y=40,z=0; k=102, pFWE-corr= 0.008).

Conclusion

Individuals with PTSD who average less sleep at night showed greater emotional reactivity, as indexed by greater functional brain activation changes within an area of the reward network, than individuals who obtained more sleep per night. Future research involving actual sleep duration manipulation will be necessary to determine whether this finding reflects the well-known antidepressant effect of sleep deprivation or a form of greater emotional expression error monitoring among traumatized patients when lacking sleep. Regardless, these findings suggest that insufficient sleep could affect unconsciously perceived emotion in faces and potentially affect social and emotional responses among individuals with PTSD.

Support

US Army Medical Research and Materiel Command: W81XWH-14-1-0570

Omega-3 fatty acids to prevent preterm birth: Australian pregnant women's preterm birth awareness and intentions to increase omega-3 fatty acid intake

BACKGROUND

Preterm birth is the leading cause of death in children under five. A recent Cochrane review found a 42% reduction in early preterm birth (< 34 weeks' gestation) and 11% reduction in preterm birth (< 37 weeks' gestation) with omega-3 fatty acid supplementation. To assist in the development of implementation strategies to increase pregnant women's omega-3 fatty acid intake, we assessed the awareness of Australian pregnant women about preterm birth, their nutrition and supplementation behaviours during pregnancy, and intentions to increase omega-3 fatty acid intake.

METHODS

A ten-minute survey was conducted online to assess the knowledge, attitudes, behaviours, and intentions of Australian pregnant women across three domains: (1) preterm birth; (2) nutrition and supplementation during pregnancy; and (3) omega-3 fatty acid consumption to prevent preterm birth. Participants were recruited from Survey Sampling International's research panels.

RESULTS

Of the 763 women who completed the survey, less than two-thirds had heard of preterm birth. Over 55% of respondents had changed their diet during pregnancy and a prenatal dietary supplement was consumed by 82% of the women surveyed. Respondents' main source of information about preterm birth and nutrition during pregnancy was from a health professional. When asked about their intentions to increase their omega-3 fatty acid intake following a health professional's recommendation, the vast majority of participants indicated they would increase their omega-3 fatty acid intake (90%). When a hypothetical scenario was presented of an omega-3 fatty acid supplement being offered from a health service at no cost, the number of respondents who selected they would increase their intake through supplementation increased from 54 to 79%.

CONCLUSIONS

The main information source for women about preterm birth and dietary supplementation recommendations during pregnancy is their health professional. Therefore, informing women about ways to prevent preterm birth, including the role of omega-3 fatty acids, should occur during antenatal visits. The results from our study are useful for clinicians caring for pregnant women and for the next stage of translation of the Cochrane review findings - the design of implementation strategies to increase the intake of omega-3 fatty acids during pregnancy where needed.

A rule-based method for predicting the electrical activation of the heart with cardiac resynchronization therapy from non-invasive clinical data

Background

Cardiac Resynchronization Therapy (CRT) is one of the few effective treatments for heart failure patients with ventricular dyssynchrony. The pacing location of the left ventricle is indicated as a determinant of CRT outcome.

Objective

Patient specific computational models allow the activation pattern following CRT implant to be predicted and this may be used to optimize CRT lead placement.

Methods

In this study, the effects of heterogeneous cardiac substrate (scar, fast endocardial conduction, slow septal conduction, functional block) on accurately predicting the electrical activation of the LV epicardium were tested to determine the minimal detail required to create a rule based model of cardiac electrophysiology. Non-invasive clinical data (CT or CMR images and 12 lead ECG) from eighteen patients from two centers were used to investigate the models.

Results

Validation with invasive electro-anatomical mapping data identified that computer models with fast endocardial conduction were able to predict the electrical activation with a mean distance errors of 9.2 ± 0.5 mm (CMR data) or (CT data) 7.5 ± 0.7 mm.

Conclusion

This study identified a simple rule-based fast endocardial conduction model, built using non-invasive clinical data that can be used to rapidly and robustly predict the electrical activation of the heart. Pre-procedural prediction of the latest electrically activating region to identify the optimal LV pacing site could potentially be a useful clinical planning tool for CRT procedures.

Differential effect with septal and apical RV pacing on ventricular activation in patients with left bundle branch block assessed by non-invasive electrical imaging and in silico modelling

Purpose

It is uncertain whether right ventricular (RV) lead position in cardiac resynchronization therapy impacts response. There has been little detailed analysis of the activation patterns in RV septal pacing (RVSP), especially in the CRT population. We compare left bundle branch block (LBBB) activation patterns with RV pacing (RVP) within the same patients with further comparison between RV apical pacing (RVAP) and RVSP.

Methods

Body surface mapping was undertaken in 14 LBBB patients after CRT implantation. Nine patients had RVAP, 5 patients had RVSP. Activation parameters included left ventricular total activation time (LVtat), biventricular total activation time (VVtat), interventricular electrical synchronicity (VVsync), and dispersion of left ventricular activation times (LVdisp). The direction of activation wave front was also compared in each patient (wave front angle (WFA)). In silico computer modelling was applied to assess the effect of RVAP and RVSP in order to validate the clinical results.

Results

Patients were aged 64.6 ± 12.2 years, 12 were male, 8 were ischemic. Baseline QRS durations were 157 ± 18 ms. There was no difference in VVtat between RVP and LBBB but a longer LVtat in RVP (102.8 ± 19.6 vs. 87.4 ± 21.1 ms, p = 0.046). VVsync was significantly greater in LBBB (45.1 ± 20.2 vs. 35.9 ± 17.1 ms, p = 0.01) but LVdisp was greater in RVP (33.4 ± 5.9 vs. 27.6 ± 6.9 ms, p = 0.025). WFA did rotate clockwise with RVP vs. LBBB (82.5 ± 25.2 vs. 62.1 ± 31.7 ^op = 0.026). None of the measurements were different to LBBB with RVSP; however, the differences were preserved with RVAP for VVsync, LVdisp, and WFA. In silico modelling corroborated these results.

Conclusions

RVAP activation differs from LBBB where RVSP appears similar.

Trial registration

(ClinicalTrials.gov identifier: NCT01831518)

Electronic supplementary material

The online version of this article (10.1007/s10840-019-00567-2) contains supplementary material, which is available to authorized users.

On-Line Monitoring of Sequential Blood Flow Reduction during Splenic Embolization

Partial embolization of the spleen has been well established for the treatment of hypersplenism. A weakness of the technique is the lack of an objective method to quantitate the flow reduction during the procedure. The video dilution technique (VDT) has earlier been used to measure blood flow in regional arteries using video cassette replay. By adapting the VDT concept of relative flow to digital subtraction angiography, it is possible to calculate the flow reduction instantly following each injection of embolic material. We present a case of partial splenic embolization where the flow in the splenic artery was reduced to a predetermined level of 50 per cent of baseline flow. The clinical results were excellent. By observing the clinical results of partial embolization, terminated at different levels of flow reduction, it will be possible to optimize the results and prevent overembolization.

Cost-Benefit Analysis for Biological Control Programs That Targeted Insect Pests of Eucalypts in Urban Landscapes of California

As well as being planted for wind breaks, landscape trees, and fuel wood, eucalypts are also widely used as urban street trees in California. They now are besieged by exotic insect herbivores of four different feeding guilds. The objective of the current analysis was to determine the return on investment from biological control programs that have targeted these pests. Independent estimates of the total number of eucalypt street trees in California ranged from a high of 476,527 trees (based on tree inventories from 135 California cities) to a low of 190,666 trees (based on 49 tree inventories). Based on a survey of 3,512 trees, the estimated mean value of an individual eucalypt was US$5,978. Thus, the total value of eucalypt street trees in California ranged from more than US$1.0 billion to more than US$2.8 billion. Biological control programs that targeted pests of eucalypts in California have cost US$2,663,097 in extramural grants and University of California salaries. Consequently, the return derived from protecting the value of this resource through the biological control efforts, per dollar expended, ranged from US$1,070 for the high estimated number of trees to US$428 for the lower estimate. The analyses demonstrate both the tremendous value of urban street trees, and the benefits that stem from successful biological control programs aimed at preserving these trees. Economic analyses such as this, which demonstrate the substantial rates of return from successful biological control of invasive pests, may play a key role in developing both grass-roots and governmental support for future urban biological control efforts.

Approaching the community about screening children for a multicentre malaria vaccine trial

Community sensitisation, as a component of community engagement, plays an important role in strengthening the ethics of community-based trials in developing countries and is fundamental to trial success. However, few researchers have shared their community sensitisation strategies and experiences. We report on our perspective as researchers on the sensitisation activities undertaken for a phase II malaria vaccine trial in Kilifi District (Kenya) and Korogwe District (Tanzania), with the aim of informing and guiding the operational planning of future trials. We report wide variability in recruitment rates within both sites; a variability that occurred against a backdrop of similarity in overall approaches to sensitisation across the two sites but significant differences in community exposure to biomedical research. We present a range of potential factors contributing to these differences in recruitment rates, which we believe are worth considering in future community sensitisation plans. We conclude by arguing for carefully designed social science research around the implementation and impact of community sensitisation activities.

P4-12-13: A Multi-Center Randomized Controlled Double Blind Trial Assessing the Effect of Acupuncture in Reducing Musculoskeletal Symptoms in Breast Cancer Patients Taking Aromatase Inhibitors: First Interim Analysis

Background: Aromatase inhibitors (AIs) are recommended as first-line adjuvant hormonal therapy in postmenopausal women with hormone-receptor-positive breast cancer, as monotherapy or sequential therapy after tamoxifen. AI-associated musculoskeletal symptoms (AIMSS) occur in approximately 50% of women receiving AIs and in some may result in discontinuation of treatment. Symptom management is essential to ensure that breast cancer patients receive the full recommended duration of AI therapy. We conducted a randomized, placebo-controlled trial to evaluate the effect of acupuncture on AIMSS and report the first interim analysis.

Method: Postmenopausal women with early stage breast cancer, experiencing AIMSS, who had not had acupuncture in the year prior to the study, were eligible. Patients were randomized to 8 weekly acupuncture or sham acupuncture. Health assessment questionnaire disability index (HAQ-DI ranging 0–3.0) and pain visual analog scale (VAS ranging 0–100) were used to assess clinical musculoskeletal disorder severity at weeks 0, 4, 8, and 12 or 24. Change in HAQ-DI (ΔHAQ-DI) and VAS scores (ΔVAS) from baseline were compared between patients receiving acupuncture versus sham acupuncture using exact Wilcoxon rank sum test. Serum samples were collected for measurements of estrogens and beta endorphin concentrations and cytokine profile before and after the intervention to evaluate the etiology of AIMSS and the mechanism of acupuncture in treating AIMSS.

Results: Between May 2008 and June 2011, 48 patients were enrolled, 2 patients were not evaluable due to noncompliance to treatment and lost to follow up, 10 were still receiving treatment and therefore not evaluable. Thirty-six were evaluable, and were equally distributed between the real and sham acupuncture groups. Baseline characteristics were balanced between the two groups with regard to age, race, and body mass index (BMI) with the exception that baseline mean HAQ-DI was higher in the acupuncture group (0.9 vs 0.55, p=0.04). White/Black/Asian: 26/7/3, Median (range): age: 61 (45-82); BMI (kg/m2): 31.1 (22.9−59.6). At week 8, both groups showed a wide range of ΔHAQ-DI (ΔHAQ-DI =HAQ-DIweek8-HAQ-DIbaseline): from −1.38 to 0.5 in the acupuncture group versus from −1 to 0.12 in sham acupuncture group. There was no statistically significant difference in mean ΔHAQ-DI between the real and sham acupuncture groups (−0.33 vs −0.33, p=0.87). Eleven patients in each group (61%) reported decreased HAQ-DI scores, which correlated with improved function. There was no difference in mean ΔVAS between the real and sham acupuncture groups (−9.27 vs −13.82, p=0.67). No significant side effects were reported. Changes in other time points and in serum biomarkers will be presented at the meeting.

Conclusions: The majority of breast cancer patients experiencing AIMSS who participated in our study reported a reduced HAQ-DI score both from acupuncture and sham acupuncture. We did not observe significant differences between responses to real versus sham acupuncture after 8 weekly treatments. The study remains open to accrual to reach 50 evaluable patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-12-13.

Bone fluoride concentrations of eastern grey kangaroos (Macropus giganteus) resident near an aluminium smelter in south-eastern Australia

Lesions of skeletal and dental fluorosis have been described recently in eastern grey kangaroos (Macropus giganteus). The present study further examined the epidemiology of skeletal fluorosis in this species. Bone fluoride concentrations were obtained from a range of skeletal sites of animals from a high (Portland Aluminium) and a low (Cape Bridgewater) fluoride environment in Victoria, Australia. Age, but not sex, affected the mean bone fluoride concentration of kangaroos. For a given age, bone fluoride concentrations were significantly higher in kangaroos from Portland than Cape Bridgewater. Concentrations varied between skeletal sites examined, with samples containing cancellous bone having higher fluoride concentrations than those containing only cortical bone.

Decisions about weight management: a synthesis of qualitative studies of obesity

There is a high non-attendance and dropout attrition from weight management interventions for adults with obesity. Patient dissatisfaction with consultations involving decisions about interventions may be a factor. A systematic review was undertaken of qualitative studies reporting perceptions, experiences, contexts and influences for adults facing, or reflecting on, weight management. The aim was to synthesize a generic model of influences on decision-making about weight management for adult patients. Electronic database and hand searches identified 29 qualitative studies involving 1387 participants (mean age 45.3 years; mean BMI 37.1 kg m(-2) ; 79.9% women). Seven overarching themes were inductively derived from extracted data spanning: cultural identity; social structures such as gender; responses to obesity stigma; previous weight loss experiences; personal motivators and barriers; social support; and practical resources. A model is presented in the paper. Improving decisions about weight management requires attention to how diffuse cultural and psycho-social factors, such as obesity stigma, influence patient choices. Reflection on experiences of previous attempts at weight loss is also essential, as are practical resource factors - particularly for less affluent groups. Considering these factors along with more established theories of individual psychological motivations and barriers may help to improve initial participation and retention within interventions.

Panel report: best practices for the surgical treatment of obesity

BACKGROUND

Bariatric surgery is a rapidly growing field. Advances in surgical technologies and techniques have raised concerns about patient safety. Bariatric surgeons and programs are under increased scrutiny from regulatory agencies, insurers, and public health officials to provide high quality and safe care for bariatric patients at all phases of care.

METHODS

During the 2009 annual meeting of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), a panel of experts convened to provide updated information on patient safety and best practices in bariatric surgery. The following article is a summary of this panel presentation.

RESULTS AND CONCLUSIONS

Weight loss surgery is a field that is evolving and adapting to multiple external pressures. Safety concerns along with increasing public scrutiny have led to a systematic approach to defining best practices, creating standards of care, and identifying mechanisms to ensure that patients consistently receive the best and most effective care possible. In many ways, bariatric surgery and multidisciplinary bariatric surgery programs may serve as a model for other programs and surgical specialties in the near future.

179. PURIFICATION AND CHARACTERISATION OF MOUSE TESTICULAR MACROPHAGES: GENE EXPRESSION RESPONSE TO LIPOPOLYSACCHARIDE ACTIVATION INDICATES AN IMMUNOSUPPRESSIVE PHENOTYPE

Studies on rat testicular macrophages (TMs) have indicated that these cells play an important role in testis function by supporting the immunosuppressive environment that protects developing germ cells and by responding to pathogens. By comparison, mouse TMs are essentially uncharacterised due to difficulties in isolating sufficient cells for study. We have established a technique for isolating 95% pure TMs from adult mice by differential adherence. Mouse TMs were cultured for 3h with saline, 10 or 100 ng/mL lipopolysaccharide (LPS) and compared with resident peritoneal macrophages (PMs) and bone marrow-derived macrophages (BMMs). Expression of inflammatory regulators was determined using real-time Q-PCR and AgilentTM microarray analysis. Microarray analysis indicated that each macrophage type displayed very distinct gene expression profiles. There were 526 genes uniquely expressed in TMs at basal levels compared with the other macrophages and 268 genes uniquely expressed by TMs after LPS treatment. Q-PCR determined that LPS induced expression of the anti-inflammatory cytokine interleukin (IL)-10 in each of the macrophage types, with BMMs the strongest responders. LPS stimulated IL-10 mRNA approximately 100-fold in TMs, but only 20-fold in PMs. The anti-inflammatory transforming growth factor-β1 was not significantly induced at this time-point in any macrophage type. In terms of pro-inflammatory mediators, the TM response to LPS was always lower compared to the BMMs. Compared to PMs, the responses of TMs were similar for the hallmark pro-inflammatory cytokine tumour necrosis factor- a, but 40% less for IL-1β. TMs were also deficient in production of IL-6 and cyclooxygenase-2 and IL-12. TMs were therefore relatively strong responders to LPS in terms of IL-10, but weak responders in terms of pro-inflammatory mediators, indicating an immunosuppressive phenotype. The isolation and gene measurement methods established in this study will allow us to use knockout and transgenic mouse models to determine the role for TMs in testicular inflammation/fibrosis models.

Health needs of children in prison

At the end of September 2002 there were 2633 children in prison in England and Wales. Since November 2002, the Children Act 1989 applies to children held in prison. The challenge to paediatricians is to recognise and meet the needs of these vulnerable and needy children. This can be achieved by putting in place similar provisions to those recommended for Looked After Children.

Directly measured mid-depth circulation in the northeastern North Atlantic Ocean

The circulation of water masses in the northeastern North Atlantic Ocean has a strong influence on global climate owing to the northward transport of warm subtropical water to high latitudes. But the ocean circulation at depths below the reach of satellite observations is difficult to measure, and only recently have comprehensive, direct observations of whole ocean basins been possible. Here we present quantitative maps of the absolute velocities at two levels in the northeastern North Atlantic as obtained from acoustically tracked floats. We find that most of the mean flow transported northward by the Gulf Stream system at the thermocline level (about 600 m depth) remains within the subpolar region, and only relatively little enters the Rockall trough or the Nordic seas. Contrary to previous work, our data indicate that warm, saline water from the Mediterranean Sea reaches the high latitudes through a combination of narrow slope currents and mixing processes. At both depths under investigation, currents cross the Mid-Atlantic Ridge preferentially over deep gaps in the ridge, demonstrating that sea-floor topography can constrain even upper-ocean circulation patterns.

Changes in speech intelligibility of postlingually deaf adults after cochlear implantation

OBJECTIVE

This study examines changes in the intelligibility of CVC words spoken by postlingually deafened adults after they have had 6 to 12 mo of experience with a cochlear implant. The hypothesis guiding the research is that the intelligibility of these speakers will improve after extended use of a cochlear implant. The paper also describes changes in CVC word intelligibility analyzed by phoneme class and by features.

DESIGN

The speech of eight postlingually deaf adults was recorded before activation of the speech processors of their cochlear implants and at 6 mo and 1 yr after activation. Seventeen listeners with no known impairment of hearing completed a word identification task while listening to each implant user's speech in noise. The percent information transmitted by the speakers in their pre- and postactivation recordings was measured for 11 English consonants and eight vowels separately.

RESULTS

An overall improvement in word intelligibility was observed: seven of the eight speakers showed improvement in vowel intelligibility and six speakers showed improvement in consonant intelligibility. However, the intelligibility of specific consonant and vowel features varied greatly across speakers.

CONCLUSIONS

Extended use of a cochlear implant by postlingually deafened adults tends to enhance their intelligibility.

Language-specific, hearing-related changes in vowel spaces: a preliminary study of English- and Spanish-speaking cochlear implant users

OBJECTIVE

This study investigates the role of hearing in vowel productions of postlingually deafened cochlear implant users. Two hypotheses are tested that derive from the view that vowel production is influenced by competing demands of intelligibility for the listener and least effort in the speaker: 1) Hearing enables a cochlear implant user to produce vowels distinctly from one another; without hearing, the speaker may give more weight to economy of effort, leading to reduced vowel separation. 2) Speakers may need to produce vowels more distinctly from one another in a language with a relatively "crowded" vowel space, such as American English, than in a language with relatively few vowels, such as Spanish. Thus, when switching between hearing and non-hearing states, English speakers may show a tradeoff between vowel distinctiveness and least effort, whereas Spanish speakers may not.

DESIGN

To test the prediction that there will be a reduction of average vowel spacing (AVS) (average intervowel distance in the F1-F2 plane) with interrupted hearing for English-speaking cochlear implant users, but no systematic change in AVS for Spanish cochlear implant users, vowel productions of seven English-speaking and seven Spanish-speaking cochlear implant users, who had been using their implants for at least 1 yr, were recorded when their implant speech processors were turned off and on several times in two sessions.

RESULTS

AVS was consistently larger for the English speakers with hearing than without hearing. The magnitude and direction of AVS change was more variable for the Spanish speakers, both within and between subjects.

CONCLUSION

Vowel distinctiveness was enhanced with the provision of some hearing in the language group with a more crowded vowel space but not in the language group with fewer vowels. The view that speakers seek to minimize effort while maintaining the distinctiveness of acoustic goals receives some support.

Covariation of cochlear implant users' perception and production of vowel contrasts and their identification by listeners with normal hearing

This study investigates covariation of perception and production of vowel contrasts in speakers who use cochlear implants and identification of those contrasts by listeners with normal hearing. Formant measures were made of seven vowel pairs whose members are neighboring in acoustic space. The vowels were produced in carrier phrases by 8 postlingually deafened adults, before and after they received their cochlear implants (CI). Improvements in a speaker's production and perception of a given vowel contrast and normally hearing listeners' identification of that contrast in masking noise tended to occur together. Specifically, speakers who produced vowel pairs with reduced contrast in the pre-CI condition (measured by separation in the acoustic vowel space) and who showed improvement in their perception of these contrasts post-CI (measured with a phoneme identification test) were found to have enhanced production contrasts post-CI in many cases. These enhanced production contrasts were associated, in turn, with enhanced masked word recognition, as measured from responses of a group of 10 normally hearing listeners. The results support the view that restoring self-hearing allows a speaker to adjust articulatory routines to ensure sufficient perceptual contrast for listeners.