The ALR-RSI score can be used to evaluate psychological readiness to return to sport after acute Achilles tendon tear

PURPOSE

The return to sport is one of the main goals following Achilles tendon tear repair. Several psychological factors influence the return to sport after a sports injury. The traditional tools to assess the return to sport do not take into account psychological factors. The ankle ligament reconstruction-return to sport injury (ALR-RSI), validated for ankle instability, is a score to evaluate psychological readiness to return to sport. The goal of this study was to validate the ALR-RSI score for the assessment of the readiness to return to sport after Achilles tendon repair.

METHODS

The ALR-RSI score, adapted from the anterior cruciate ligament-return to sport injury (ACL-RSI) score used following knee ligament reconstruction, was validated according to the international COSMIN methodology. Patients operated for Achilles tendon repair responded to the questionnaire during the rehabilitation period. The EFAS, FAAM and VISA-A scores were used as reference questionnaires.

RESULTS

A total of 50 patients were included. The ALR-RSI score was strongly (r > 0.5) correlated to the EFAS score: r = 0.68 [0.50-0.80] the FAMM sport score: r = 0.7 [0.52-0.84] the FAAM AVQ score (r = 0.6 [0.35-0.78]), and the VISA-A score (r = 0.54 [0.26-0.76]). The discriminant validity was good with the ALR-RSI, which was significantly lower in the patients that did not return to sport: 60.7 (40-81.4) compared to those that did: 83.2 (64.3-100) p = 0.001. Reproducibility was excellent with an intra-class correlation coefficient ρ of 0.99 [097-1.00]. The internal consistency was excellent (alpha coefficient = 0.95).

CONCLUSION

The ALR-RSI score provides a valid, reproducible assessment of the psychological readiness to return to sport in patients who undergo surgical Achilles tendon suture repair.

LEVEL OF EVIDENCE

III.

Applicability of 'Toolkit for Safety Assessment' tool to interventional radiology using probabilistic risk assessment techniques

Interventional radiology brings extensive benefits to patients. Nevertheless, certain procedures may result in high doses of radiation, leading to health risks to occupationally exposed individuals (OEIs). Therefore, a more comprehensive risk analysis is essential to ensuring safety and minimising radiation exposures for all OEIs. The Toolkit for Safety Assessment (TOKSA) tool performs risk assessments based on the concepts described in 'General Safety Requirements' Part 3 (Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards) and Part 4 (Safety Assessment for Facilities and Activities). This tool was developed based on the 'Ibero-American Forum of Radiological and Nuclear Regulatory Agencies' risk models and can promote the use of the risk assessment processes by OEIs. The aim of this study was to experimentally analyse the applicability of the TOKSA tool in interventional radiology with the use/support of probabilistic risk assessment techniques. The results were used to reduce the risks associated with a hemodynamics room in a hospital in Belo Horizonte, Brazil.

Gut microbiota promoting propionic acid production accompanies diet-induced intentional weight loss in cats

Rodent models and human clinical studies have shown gut microbiota-derived short-chain fatty acids (SCFAs) play roles in obesity and insulin resistance. These roles have been minimally explored in cats, where in the USA an estimated 60% of cats are overweight or obese. Overweight/obese research cats (n = 7) were transitioned from a maintenance diet to a reduced calorie diet fed ad libitum for seven days, then calories were restricted to achieve 1-2% weight loss per week for an additional 77 days. Cats then received their original maintenance diet again for 14 days. Significant intentional weight loss was noted after calorie restriction (adjusted p < 0.0001). 16S rRNA gene amplicon sequencing and targeted SCFA metabolomics were performed on fecal samples. Fecal microbial community structure significantly differed between the four study phases (PERMANOVA p = 0.011). Fecal propionic acid was significantly higher during diet-induced weight loss (adjusted p < 0.05). Spearman correlation revealed the relative abundances of Prevotella 9 copri (ρ = 0.6385, p = 0.0006) and Blautia caecimuris (ρ = 0.5269, p = 0.0068) were significantly correlated with propionic acid composition. Like humans, obese cats experienced an altered microbial community structure and function, favoring propionic acid production, during diet-induced weight loss.

Differing approaches to analyse on-treatment cardiovascular events comparing daprodustat with darbepoetin: results from the ASCEND-ND trial

Background

Hypoxia-inducible factor prolyl hydroxylase inhibitors (HIF-PHIs) represent a potential new therapeutic option to treat anaemia of chronic kidney disease (CKD).

Purpose

In the recent ASCEND-ND trial (NCT02876835)1, conducted in patients with anaemia of CKD not requiring dialysis, the HIF-PHI daprodustat was non-inferior to darbepoetin for cardiovascular (CV) events in the primary intention-to-treat analysis (HR 1.03; 95% CI 0.89, 1.19); however, a prespecified on-treatment analysis raised concerns about a higher risk of CV events associated with daprodustat compared to darbepoetin (HR 1.40; 95% CI 1.17, 1.68). Our analysis explored potential reasons to explain the differences between on-treatment and intention-to-treat analyses in ASCEND-ND.

Methods

Overall, 3872 patients were randomised to receive either oral daprodustat (daily) or darbepoetin alfa given weekly, every 2 weeks, or every 4 weeks in an open-label fashion (last dosing frequency for darbepoetin was 7% weekly, 15% every 2 weeks, and 78% every 4 weeks). Patients were followed for development of the composite CV outcome (all-cause death, first non-fatal myocardial infarction, or first non-fatal stroke). The prespecified on-treatment approach included CV events up to 28 days following the last non-zero dose date of randomised therapy (Figure 1). Post-hoc analyses used Cox regression models to assess the impact of different follow-up periods (indexed to last non-zero dose date, treatment stop (discontinuation) date, and dosing intervals) on the treatment effect estimate.

Results

Different definitions of “on-treatment” using alternative censoring approaches resulted in hazard ratios for the CV composite outcome for daprodustat vs. darbepoetin that ranged from 1.06 (95% CI 0.89, 1.27) censored at treatment stop date; 1.09 (95% CI 0.89, 1.33) censored at last non-zero dose date + dosing interval; 1.54 (95% CI 1.20, 1.97) censored at the last non-zero dose date (Figure 2). As a result of the differential dosing interval, the gap between the last non-zero dose date and CV event date was 15 [1 to 134] days in the daprodustat arm, and 35 [13 to 134] days prior in the darbepoetin arm. This resulted in identical patients (i.e., identical treatment stop dates and event dates) being more likely to count as “on-treatment” in the daprodustat arm (Figure 1). This artefactual difference was not observed in analyses that were indexed to the treatment stop date, nor in analyses that accounted for the different dosing intervals for darbepoetin.

Conclusion

In the ASCEND-ND trial, different dosing frequencies introduced longer intervals between the last non-zero dose date and date of CV outcomes in the darbepoetin arm, compared with daprodustat. This artefact led to inappropriate undercounting of CV events in the darbepoetin arm. Accounting for the differential intervals resulted in neutral effect estimates, which were consistent with those observed with intention-to-treat approaches.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): ASCEND-ND was funded by GlaxoSmithKline

Higher preoperative range of motion is predictive of good mid-term results in the surgical management of osteochondral lesions of the talus: a prospective multicentric study

INTRODUCTION

Osteochondral lesions of the talus (OLT) are a frequent cause of pain in young patients and a new CT arthrographic classification system of OLT was recently proposed to help guide the choices of and standardize the indications for surgical treatment. The primary hypothesis was that this algorithm would result in a postoperative AOFAS score of ≥ 80/100. The secondary hypothesis was to identify the preoperative factors of successful surgery.

METHODS

This was a prospective observational multicenter study. Eighty-six patients who underwent surgery for OLT after at least 6 months of unsuccessful conservative management were included for a mean follow-up of 15 months (12-36). Forty-nine patients with stage 1 OLT underwent microperforation, 2 patients with stage 2 OLT underwent a lift, drill, fill, and fix graft procedure with screw fixation, and 35 patients with stage 3 OLT were treated with mosaicplasty.

RESULTS

After a follow-up of at least 1 year, 56 patients (65%) had an AOFAS score > 80 and the mean AOFAS score was 82 (16-100). A lower BMI (p = 0.038), a higher preoperative range of motion in the ankle (p = 0.033), higher preoperative AOFAS and FAOS scores (p = 0.001 and p = 0.011), and the presence of a preoperative bone bruise on MRI (p = 0.020) were good prognostic factors on univariate analysis. The presence of grade 1 osteoarthritis on the Van Dijk classification was predictive of a poor prognosis (p = 0.044). Multivariate analysis showed that a good preoperative range of motion (OR = 1.080 [1.020-1.150] p = 0.01) was predictive of a positive outcome, while grade 1 osteoarthritis was predictive of a poor outcome (OR = 0.147 [0.036-0.603] p = 0.008). The postoperative AOFAS decreased in six patients and 17 patients had at least one complication: six dysthesias of the superficial fibular nerve, two of the sural nerve, and nine stage 1 complex regional pain syndromes.

CONCLUSION

The new algorithm for OLT resulted in a postoperative AOFAS score of ≥ 80/100 in 65% of cases. The positive predictive factors of a successful postoperative outcome were the presence of a good preoperative range of motion and the absence of preoperative osteoarthritis.

LEVEL OF EVIDENCE

Level II.

Functional connectivity and cognitive changes after donepezil treatment in healthy participants

RATIONALE

Donepezil is a potent, noncompetitive, reversible, clinically effective acetylcholinesterase inhibitor. The effects of this drug on healthy brains have seldom been investigated.

OBJECTIVES

The primary objective of the present study was to identify possible functional connectivity markers of the effect of donepezil in healthy young adult volunteers.

METHODS

The study had a double-blind, randomized, crossover design. 30 healthy adult volunteers underwent resting-state MRI scans during 15 days of donepezil or placebo treatment, in accordance with the design.

RESULTS

Results showed significant differences in intrinsic functional connectivity between donepezil and placebo, mainly in the right executive control network (RECN). More specifically, we found a decrease in the connectivity of the right inferior parietal node with other RECN nodes. Analysis using the cingulate cortex and parahippocampal regions as seeds also revealed complex modulation of functional connectivity in the donepezil condition.

CONCLUSIONS

In conclusion, donepezil treatment for 15 days may result in reorganization of resting-state networks, compared with placebo.

Brief International Cognitive Assessment for Multiple Sclerosis scores are associated with the cortical thickness of specific cortical areas in relapsing-remitting patients

BACKGROUND

Cognitive impairment is frequent and disabling in multiple sclerosis (MS). The Brief International Cognitive Assessment in MS (BICAMS) is a recent short battery usable in clinical practice for cognitive evaluation of MS patients.

OBJECTIVE

To find cortical areas or brain volumes on magnetic resonance imaging (MRI) structural sequences associated with BICAMS scores in MS.

METHODS

In this cross-sectional single-center study (NCT03656055, September 4, 2018), 96 relapsing remitting-MS patients under natalizumab and without recent clinical or radiological inflammation were included. Patients underwent brain MRI and the three BICAMS tests, evaluating information processing speed (SDMT), visuo-spatial memory (BVMT-R), and verbal memory (FVLT).

RESULTS

Cortical thickness in the left frontal superior and the right precentral gyri was associated with BVMT-R scores whereas cortical thickness in the left Broca's area and the right superior temporal gyrus was associated with FVLT scores. We observed associations between white matter inflammatory lesions connected to these cortical regions and BICAMS subscores.

CONCLUSIONS

BICAMS scores are associated with specific cortical areas, the cognitive domain matching the known functions of the cortical area. Specific cognitive impairments in MS may be associated with specific cortical regions, themselves influenced by white matter inflammatory lesions and demographical parameters (age, sex, education level).

Global representation of heart failure clinical trial leaders and collaborators: a systematic bibliometric review 2000–2020

Aims

Heart Failure (HF) has a disproportionate burden in low- and middle-income countries. The geographic representation of those who lead HF randomized clinical trials (RCTs) may not reflect the geographic burden of disease. We assessed temporal trends and trial characteristics associated with leadership outside Europe and North America, and explored whether there was a geographic association between trial leadership and participant enrolment.

Methods and results

We searched MEDLINE, EMBASE, and CINAHL for HF RCTs published in journals with an impact factor ≥10 between January 1, 2000, and June 17, 2020. We used the Jonckheere-Terpstra test to assess temporal trends and multivariable logistic regression models to determine associations between predictor and outcome variables.

There were 414 eligible RCTs. Only 80 of 828 trial leaders (9.7%; 95% CI: 7.8% to 11.8%), and 453 of 4656 collaborators (9.7%; 95% CI: 8.8% to 10.6%) were from regions outside Europe and North America, with no temporal change in geographic representation. The odds of trial leadership outside Europe and North America were significantly lower with industry versus public funding (OR: 0.33; 95% CI: 0.15 to 0.75; P=0.008). Trial leadership outside Europe and North America was associated with enrolment of patients outside Europe and North America (OR: 10.0; 95% CI 5.6–19.0; P&lt;0.001).

Conclusion

Trial leadership outside Europe and North America is rare, particularly in industry funded trials, and is associated with participant enrolment in regions with disproportionate disease burden. Building research capacity and networks in under-represented regions could increase generalizability of trial results.

Funding Acknowledgement

Type of funding sources: None.

Pharmacokinetics of apixaban in patients with end stage renal disease on hemodialysis and atrial fibrillation: results from the RENAL-AF trial

Background/Introduction

Apixaban use is increasing for stroke prevention in patients with atrial fibrillation (AF) and end stage renal disease (ESRD) on hemodialysis. There is uncertainty as to the optimal dose in this population in part related to the limited available pharmacokinetic (PK) data.

Purpose

We comprehensively evaluated the PK of apixaban collected over 1 month of apixaban dosing in 63 patients with AF and ESRD on hemodialysis.

Methods

Patients with AF and ESRD on hemodialysis were randomized to warfarin versus apixaban within the RENAL-AF trial with 5 mg BID dosing, except for 2.5 mg BID in those age ≥80 years or weight ≤60 kg. The 5 mg BID dose could be reduced to 2.5mg BID for minor bleeding. Day 1 PK data was collected on all patients pre- and post-hemodialysis. Day 3 and 1 month pre- and post-hemodialysis PK samples were collected in 49 patients. The timing of apixaban dosing and hemodialysis relative to PK samples was recorded. Dosing history, hemodialysis, and PK samples were chronologically integrated with patient specific data such as body size, age, race and gender. This dataset was combined with the ARISTOTLE dataset, and the published PK model from ARISTOTLE describing exposures in the AF population was updated to incorporate an additional clearance term for hemodialysis. The model estimated apixaban exposures (AUC) in RENAL-AF were compared to ARISTOLTE AUC values.

Results

There were 285 PK concentrations collected among 63 patients in the RENAL-AF trial. Patients had median age 69 years with 41% women (N=26) and a median weight of 84 kg (49, 157). The median AUCs for patients with ESRD on hemodialysis were 5,452 and 2,990 for patients treated with 5mg BID and 2.5mg BID doses, respectively. The median AUCs for patients treated with 5mg BID from ARISTOTLE increased from 2,802 for patients with class 1 CKD to 5,863 for class 4 CKD, while they increased from 2,392 for class 1 CKD to 2,881 for class 4 CKD in patients treated with 2.5mg BID. The median AUC for patients with ESRD on hemodialysis were within 50% of the exposure of patients from ARISTOTLE for all classes of CKD for the 2.5mg BID dose and for classes 2, 3A, 3B, and 4 CKD for the 5mg BID dose (Figure).

Conclusions

The steady state apixaban exposure data in patients with AF and ESRD on hemodialysis were modestly higher but consistent with the results of non-ESRD patients from ARISTOTLE, using 5 mg BID unless patients had age ≥80 years or weight ≤60 kg. Additional clinical outcomes data on the use of apixaban in patients with AF and ESRD on hemodialysis are needed.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Investigator sponsored grant from Bristol-Myers Squibb and Pfizer

Choice of P2Y12 inhibitor and clinical outcomes in the AUGUSTUS study: support for an individualised approach

Background

AUGUSTUS randomized patients with atrial fibrillation and ACS and/or PCI to apixaban or VKA and aspirin or placebo for 6 months on background P2Y12 inhibitor.

Purpose

To characterise the clinical outcomes in patients receiving clopidogrel or ticagrelor.

Methods

Patients enrolled in AUGUSTUS (n=4614) were grouped by P2Y12 inhibitor at randomization. Baseline characteristics were compared among groups. Rates of ISTH major or CRNM bleeding, definite/probable stent thrombosis (ST), stroke, MI, and death or ischaemic event were quantified and treatment groups were compared according to treatment with clopidogrel or ticagrelor.

Results

At randomization, patients were treated with clopidogrel (n=4165), ticagrelor (n=280), prasugrel (n=51) or no P2Y12 inhibitor (n=118). Median ages were 71, 69, 66 and 72 years (P&lt;0.001). Ticagrelor and prasugrel were more commonly used in PCI-managed ACS (53% and 55%) whilst clopidogrel or no P2Y12 inhibitor was more common in medically-managed ACS (25% and 36%); elective PCI was the index event in 37–41% for each group. Irrespective of P2Y12 inhibitor used, bleeding risk was lower with apixaban vs. VKA and higher with aspirin vs. placebo (Table). ST rate was lowest but major/CRNM bleeding rate highest with ticagrelor + aspirin vs ticagrelor without aspirin or clopidogrel with or without aspirin.

Conclusions

Apixaban is safer than VKA regardless of P2Y12 inhibitor used. Dropping aspirin reduces bleeding but is associated with numerically higher ST rates regardless of P2Y12 inhibitor used. These data support current recommendations for preferential use of NOAC vs. VKA and individualised choice of P2Y12 inhibitor and timing of aspirin cessation after PCI according to the patient's risks of bleeding and stent thrombosis.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Bristol-Myers Squibb/Pfizer

Safety and efficacy of antithrombotic therapy according to stroke and bleeding risk in patients with atrial fibrillation and acute coronary syndrome or PCI: insights from AUGUSTUS

Background

The AUGUSTUS trial showed that patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) and/or PCI treated with a P2Y12 inhibitor and apixaban resulted in less bleeding and comparable ischemic events compared with regimens that included a vitamin K antagonist (VKA), aspirin, or both. We assessed the effect of apixaban versus VKA and aspirin versus placebo according to patients' baseline risk of stroke and bleeding.

Methods

AUGUSTUS randomized 4614 patients in a two-by-two factorial design to open label apixaban or VKA and blinded aspirin or placebo. The primary endpoint was major or clinically relevant nonmajor (CRNM) bleeding over 6 months of follow-up. The effects were assessed stratified by baseline CHA2DS2-VASc and HAS-BLED score using Cox proportional hazards models.

Results

4386 patients were included for this analysis. The median age was 71 (64–77) years, 29.4% were female, 81.7% had a CHA2DS2-VASc score≥3, and 66.8% a HAS-BLED score≥3. As shown in the table, rates of bleeding were lower with apixaban (vs VKA) irrespective of baseline bleeding risk (p-value interaction: 0.23). Aspirin (vs placebo) was associated with increased bleeding irrespective of baseline risk (p-value interaction: 0.88). Apixaban use was associated with a lower risk of death or hospitalization without a significant interaction with stroke risk (p-value of interaction=0.53). No differences were found for ischemic outcomes.

Conclusion

An antithrombotic regimen including a P2Y12 inhibitor and apixaban is associated with less bleeding and hospitalization compared to a regimen with VKA, aspirin, or both with results consistent across CHA2DS2-VASc, and HAS-BLED scores. Our findings support the use of apixaban and a P2Y12 inhibitor without aspirin during the first 6 months for most patients with AF and ACS and/or PCI, regardless of stroke and bleeding risk.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): The Augustus trial was sponsored by Bristol-Myers Squibb and Pfizer, Inc

Effect of alirocumab on incidence of atrial fibrillation after acute coronary syndromes: insights from ODYSSEY OUTCOMES

Background

Atrial fibrillation (AF) is a marker of risk in patients presenting with acute coronary syndromes (ACS). The potential effect of inhibiting proprotein convertase subtilisin/kexin type 9 (PCSK9) on the incidence of AF is unknown.

Methods

The ODYSSEY OUTCOMES trial compared randomized treatment with the PCSK9 inhibitor alirocumab or placebo in patients with recent ACS and residual dyslipidaemia despite optimal statin therapy. The current analysis determined: 1) whether alirocumab treatment influenced incident AF; 2) whether a history of AF influenced the risk of major adverse cardiovascular events (MACE); and 3) whether there was interaction between AF at baseline and randomized treatment on MACE. AF was determined from the medical history and investigator reports of adverse events.

Results

Of 18,924 participants, 662 (3.5%) had a history of AF at randomization and 18,262 (96.5%) had no history of AF. Of the latter category, 499 (2.7%) had incident AF. Older age, randomization in South America or Eastern Europe, history of heart failure or myocardial infarction, and higher body mass index were factors associated with incident AF. Treatment with alirocumab or placebo did not influence incident AF (2.2% vs 2.6%, respectively; hazard ratio 0.90, 95% confidence interval 0.75–1.08; Figure). Patients with a history of AF had a greater burden of comorbidities, including cerebrovascular disease, peripheral artery disease, hypertension and heart failure; they also had higher rates of MACE (Table). There was no significant interaction between AF and randomized treatment on risk of MACE (P interaction=0.78)

Conclusions

Although treatment with alirocumab did not significantly modify the risk of incident AF after ACS in this analysis, future studies with more sensitive and systematic methods of ascertainment may be warranted. History of AF is a strong predictor of risk of recurrent MACE after ACS.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Sanofi, Regeneron Pharmaceuticals, Inc

Comparison of demographic features and prognosis between cardiogenic shock in patients with Chagas heart disease and other etiologies – Registry Of Acute Medical Emergencies in Brazil (ROAD)

Background

Chagas disease is a chronic, systemic, parasitic infection caused by Trypanosoma cruzi, and a common cause of heart failure (HF) in Latin America. The incidence can be as high as 14% in endemic areas. The prognosis seems to be worse than other causes of HF, with mortality of up to 20%/year. Mortality and prognosis during the acute decompensation, however, are less studied.

Purpose

Compare differences between cardiogenic shock (CS) in patients with HF caused by chronic Chagas heart disease (ChHD) and those caused by other etiologies (non-ChHD).

Methods

We performed a multicentric, prospective, observational study of patients admitted with CS at 3 emergency departments in Brazil between January 2015 and December 2019. Baseline characteristics and intrahospital outcomes were obtained. Statistical analysis: The primary outcome was combined intra-hospital events (death, stroke, acute renal failure and bleeding). Comparison between groups was performed through Chi-squared and Student's T-test and the multivariate analysis by logistic regression, being p&lt;0.05 considered significant.

Results

856 patients with CS were included, 158 (18,5%) ChHD and 698 (81,5%) non-ChHD. Those with ChHD were younger (60.5±11.7 vs. 64.9±4.8 years old, p&lt;0.0001), less often male (50.0 vs. 64.3%, p=0.001) and had lower prevalence of diabetes (20.9 vs. 36.2%, p&lt;0.0001), hypertension (36.07 vs. 64.1%, p&lt;0.0001), chronic obstructive pulmonary disease (1.9 vs. 7.8%, p=0.007) and dyslipidemia (14.6 vs. 36%, p&lt;0.0001). The ejection fraction was lower in ChHD (26 + 7.3 vs. 30.4% + 11.4, p&lt;0.0001) and they had more definitive pacemaker (17.3 vs. 6.8%, p&lt;0.0001). At the admission, patients with ChHD had lower systolic blood pressure (91.3±20.6 vs. 98.8±25.9 mmHg, p=0.001) and were more symptomatic, with orthopnea (41.3 vs. 28.3%, p=0.004), dyspnea (75.3 vs. 57.3%, p&lt;0.0001). Treatment in the first 24 hours was different, with less withdrawal of beta-blockers (51.2 vs. 63.9%, p=0.006) and more use dobutamine (80.4 vs. 66.2%, p&lt;0.0001). Main cause of decompensation was progression of disease in 39.1% of ChHD versus 22.9% of non-ChHD (p&lt;0.001). Decompensation seemed more severe with greater necessity of orotracheal intubation (30 vs. 14.5%, p&lt;0.0001), intra-aortic balloon pump (27.9 vs. 7.5%, p&lt;0.0001), bleeding (9.2 vs. 3.8%, p=0.012) and acute renal failure (46.7 vs. 35.8%, p=0.024). The primary outcome was observed in 57% of the non-ChHD and 71.5% of the ChHD (OR 0.578, 95% CI: 0.314–1.064, p=0.079). Also, there were no differences between intra-hospital mortality in patients with ChHD versus non-ChHD (37.3 vs. 32.7%, p=0.261).

Conclusion

To the best of our knowledge, this is the biggest registry with Chagasic patients in cardiogenic shock. They were younger and had less comorbidities, but were admitted with lower blood pressure, more symptoms and needed more inotropes in the first 24 hours. No difference in mortality or combined outcome was observed.

Funding Acknowledgement

Type of funding source: None

Incidence and risk of short episodes of atrial fibrillation detected with 14 days of continuous electrocardiographic monitoring

Background

There is widespread interest in population-based screening for atrial fibrillation (AF). However, there is debate regarding the optimal screening method and duration.

Objectives

To estimate the incidence of short-duration AF detected by a single continuous 14-day electrocardiographic (ECG) monitor in older individuals without prior AF and to estimate the risk of ischemic stroke or systemic embolism associated with these episodes.

Methods

Pacemaker and defibrillator electrograms were reviewed from a cohort of individuals ≥65 years old, with a history of hypertension, but no prior AF. For each participant, we simulated a continuous 14-day ECG monitor by randomly selecting a 14-day window in the 6 months following enrolment and measured the total AF burden during that period. We repeated random sampling 1000 times to ensure a robust estimate of the likelihood of capturing AF in a single 14-day period. We used Cox proportional hazards models adjusted for CHA2DS2-VASc score to estimate the risk of ischemic stroke or systemic embolism associated with different burdens of AF.

Results

Among 2470 participants with at least 6 months of follow-up, the mean CHA2DS2-VASc score was 4.0±1.3. The proportion of participants with an AF burden of &gt;6 min on a single 14-day monitor was estimated as 3.1%, while the proportion with burdens of &gt;15 min and &gt;30 min were 2.9% and 2.6%, respectively.

Over a mean follow-up of 2.5 years, 44 participants had an ischemic stroke or systemic embolism; the rate among patients with an AF burden ≤6 mins was 0.70%/year. An AF burden &gt;6 min was associated with an increased risk of stroke or systemic embolism (2.2%/year, HR 3.0; 95% CI 1.3–5.7), as were burdens &gt;15 min (2.4%/year; HR 3.3; 95% CI 1.4–6.4) and &gt;30 min (2.6%/year HR 3.5; 95% CI 1.5–6.7).

Conclusion

Approximately 3% of individuals aged 65 years and older and with hypertension may have previously undiagnosed asymptomatic AF detected by a single 14-day continuous ECG monitor. As little as 6 minutes of AF may be associated with an increased risk of stroke. Randomized clinical trials are required to definitively assess screening in this population.

Funding Acknowledgement

Type of funding source: None

Microfluidic approach for controlled ultraviolet treatment of colored and fluorescent dissolved organic matter

Using microfluidic systems to address the optical properties of Colored and Fluorescent Dissolved Organic Matter (CDOM/FDOM) offers new ways for researching its interactions with the environment, and its response to rapid, as well as extreme, changes of abiotic conditions. Here we present a microfluidic device with an Ultraviolet (UV) component. The manufactured microfluidic device consists of passing a dissolved organic matter sample through a microchannel applying a combination of treatments using different UV wavelengths and exposure times. Here we test the workability of the microdevice by analyzing the effect of UV light on CDOM and FDOM, using as irradiations UVA and UVB to incite photodegradation, over different times. We then compare the absorbance and fluorescence, measured from both treated and non-treated samples. The analysis of the measurements is done by the calculation of the slope ratio, as indicative of molecular weight and dissolved organic carbon, besides the fluorescence humification index (HIX) as an overview of the difference between treated and non-treated of the excitation-emission matrices (EEMs). Our results show the efficiency of the microdevice by demonstrating a direct relation of degradation degree with exposure time. FDOM exposure to UVB shows a possible relation to humic-like fluorophores intensity, shown in HIX and the overview difference. Furthermore, the changes showed in the slope ratio demonstrate photodegradation in all treatments, with UVB exhibiting an increased influence. The combination of microfluidic sample treatment within in situ applications of optical sensors will enhance our capacities in addressing biogeochemical processes in the marine environment, which were not accessible with conventional bulk methods.

Structural Connectivity and Cortical Thickness Alterations in Transient Global Amnesia

BACKGROUND AND PURPOSE

Transient global amnesia (TGA) is a sudden onset of anterograde and retrograde amnesia. We aimed to assess differences in terms of cortical thickness and structural brain connectome between patients with TGA (at acute and delayed postrecovery stages) and matched controls.

MATERIALS AND METHODS

We report on 18 consecutive patients with TGA who underwent 3T MR imaging, including DTI and MPRAGE sequences, at the acute (mean delay postonset: 44 hours) and delayed post-recovery (mean delay: 35 days) stages. Structural connectome was assessed in patients with TGA and in 18 age- and sex-matched controls by using probabilistic fiber- tracking and segmentation of 164 cortical/subcortical structures ("nodes"). Connectivity graphs were computed and global network metrics were calculated. Network-based statistical analysis (NBS) was applied to compare patients with TGA at each stage with controls. We also compared cortical thickness between patients with TGA and healthy controls.

RESULTS

Global network metrics were not altered in patients with TGA. NBS-analysis showed structural connectome alterations in patients with TGA compared with controls, in core regions involving the limbic network, with 113 nodes and 114 connections (33 left intrahemispheric, 31 right intrahemispheric, and 50 interhemispheric connections) showing significantly decreased structural connectivity (P < .05 NBS corrected, t-values ranging from 3.03 to 8.73). Lower cortical thickness compared with controls was associated with these structural alterations in patients with TGA, involving the orbitofrontal, cingulate, and inferior temporal cortices. All the abnormalities were visible at both acute and delayed postrecovery stages.

CONCLUSIONS

Our preliminary study suggests there are structural abnormalities of the limbic network in patients with TGA compared with controls, including decreased structural connectivity and cortical thickness.

1414Vasodilator challenge with levosimendan as alternative to nitric oxide in advanced heart failure heart transplant candidates

Introduction

Vasodilator challenge (VC) during right heart catheterization in heart transplant (HTx) candidates is warranted whenever pulmonary artery (PA) systolic pressure ≥50 mmHg and either transpulmonary gradient (TPG) ≥15 mmHg or pulmonary vascular resistance (PVR) >3 WU as long as systolic arterial blood pressure >85 mmHg. Nitric oxide (NO) remains the mainstay but in doubtful cases a 24–48h course of diuretics, inotropes and vasoactive agents may be required. Our aim is to report our centre's experience with levosimendan (LEVO) as alternative to NO in VC in HTx candidates due to advanced heart failure (HF).

Methods

VC records with either NO (20 ppm for 5–10 mins) or within 72h of LEVO infusion (12 mg/kg/min for 24–48h) carried out between 2009 and September 2018 were retrieved from the centre's database. Analysis was carried out with Fisher's exact test or Student's t-test for categorical and continuous variables, respectively, or the equivalent non-parametric test for non-normal distribution variables. Data are presented as counts and percentage, or mean ± standard deviation and median, percentile 25–75, for categorical and continuous variables, respectively.

Results

Baseline demographic and clinical characteristics from 26 patients (NO=13; LEVO=13) were similar between groups (12% female; 54±10 years of age; left ventricular ejection fraction 20±7%; BNP 1550±1090 pg/mL; 88% on NYHA III-IV). Although no differences were observed in baseline cardiac index (CI, 1.6±0.3 vs 1.4±0.4 L/min.m-2, in NO and LEVO, respectively), LEVO patients showed higher right ventricular systolic (70±10 vs 60±13 mmHg; p=0.036) and diastolic pressures (16±4 vs 11±5 mmHg; p=0.009) and lower PA compliance (0.9±0.2 vs 1.3±0.4 ml/mmHg; p=0.007) as well as a trend for increased PA wedge pressure (26±4 vs 21±4 mmHg; p=0.09), translating worse hemodynamics. Upon VC only LEVO decreased PA pressure and the increase in CI was higher compared with NO (2.5±0.8 vs 1.9±0.5 L/min.m-2, p=0.004) thus PVR reduction was comparable between groups (7.8±2.7 to 4.7±1.8 vs 6.3±2.3 to 3.6±2.1 WU, respectively). Also, only LEVO increased right (497, 387–837 to 791, 570–946 mmHg.mL.m-2; p=0.006) and left ventricular stroke work index (895, 807–1364 to 1257, 1107–2957 mmHg.mL.m-2; p=0.005) and cardiac power output (0.4±0.1 to 0.6±0.1 W; p<0.001). Increase in PA compliance was also higher in LEVO (89±98 vs 22±30 Δ%, p=0.04). On the other hand, NO increased wedge pressure whereas LEVO had no effect thus TPG reduction was higher with NO (42±24% vs 17±27% drops, respectively; p=0.022). After HTx (NO=4; LEVO=10) mortality was similar in both groups (25% vs 30%; p=1.00).

Conclusion

LEVO is a safe and effective alternative in PVR reduction for VC. Its positive inotropic effect and long-lasting hemodynamic improvement may improve clinical status before HTx and allow better scrutiny of suitable candidates.

Cognitive behavioural therapy for anxiety disorders in Parkinson's disease: Design of a randomised controlled trial to assess clinical effectiveness and changes in cerebral connectivity

BACKGROUND

Anxiety disorders occur in up to 35% of patients with Parkinson's disease (PD) and have a negative effect on motor symptoms and quality of life. To date, no clinical trials specifically targeting anxiety in PD patients have been published.

OBJECTIVE

To describe the rationale and methodology of a randomised controlled trial (RCT) that aims to study the clinical effectiveness, alterations in brain circuitry, and cost-effectiveness of cognitive behavioural therapy (CBT) for anxiety in PD.

METHODS

This study is a prospective, two-centre RCT in which sixty PD patients with anxiety will be randomised to CBT treatment and clinical monitoring (intervention group) or to clinical monitoring only (control group). The CBT module used in this study was specifically developed to address symptoms of anxiety in PD patients. Participants will undergo standardised clinical, cognitive and behavioural assessment at baseline and at 2 follow-up measurements, as well as resting-state fMRI and DTI scanning before and after the intervention. The primary outcome measure is changes in severity of anxiety symptoms. Secondary outcome measures involve long-term changes in anxiety symptoms, changes in functional and structural connectivity between limbic and frontal cortices, and cost-effectiveness of the treatment. The study is registered at the ClinicalTrials.gov database under registration number NCT02648737.

CONCLUSION

This study is the first that evaluates both the clinical effectiveness, cost-effectiveness, as well as the biological impact of CBT for anxiety in PD patients that, if proven effective, will hopefully contribute to a better and evidence-based approach for these non-motor symptoms.

Blood Flow Mimicking Aneurysmal Wall Enhancement: A Diagnostic Pitfall of Vessel Wall MRI Using the Postcontrast 3D Turbo Spin-Echo MR Imaging Sequence

Our aim was to compare the detectability of aneurysmal wall enhancement in unruptured intracranial aneurysms between conventional and motion-sensitized driven equilibrium-prepared postcontrast 3D T1-weighted TSE sequences (sampling perfection with applicationoptimized contrasts by using different flip angle evolution, SPACE). Twenty-two patients with 30 unruptured intracranial aneurysms were scanned at 3T. Aneurysmal wall enhancement was more significantly detected using conventional compared with motion-sensitized driven equilibrium-prepared SPACE sequences (10/30 versus 2/30, P < .0001). Contrast-to-noise ratio measurements did not differ between conventional and motion-sensitized driven equilibrium-prepared sequences (P = .51). Flowing blood can mimic aneurysmal wall enhancement using conventional SPACE sequences with potential implications for patient care.

Anatomic validation of the lateral malleolus as a cutaneous marker for the distal insertion of the calcaneofibular ligament

PURPOSE

An anatomic study was performed to confirm whether the lateral malleolus could serve as a simple and reproducible anatomic reference for the distal insertion of the calcaneofibular ligament (CFL).

METHODS

Dissection was performed after placement of a Kirschner wire to simulate the calcaneal tunnel for the distal insertion of the CFL. The skin was penetrated 1 cm distal and posterior to the tip of the lateral malleolus. The main information recorded was the distance from the Kirschner wire to the centre of the distal insertion of the CFL. Other elements were noted (characteristics of the CFL, distance between the distal insertion of the CFL-peroneal tubercle, nerve or tendon injuries).

RESULTS

Thirty ankles were dissected. The mean distance from the Kirschner wire to the centre of the distal insertion of the CFL was 2.4 ± 1.8 mm. Only one case of peroneal injury was noted. The sural nerve was usually located a mean 1.8 ± 1.1 mm from the Kirschner wire. The posterior tibial vascular pedicle was a mean 27.8 ± 3.5 mm from the point of exit of the Kirschner wire.

CONCLUSION

Using the lateral malleolus as the cutaneous reference for the distal insertion of the CFL seems to be more reliable than the pure arthroscopic technique. This study describes a percutaneous technique to obtain a calcaneal tunnel for distal insertion of the CFL. The sural nerve is at the greatest risk of injury with this technique and requires careful subcutaneous incision to prevent injury. This new percutaneous technique is less invasive than a purely arthroscopic technique and more accurately identifies the location of the tunnel. It can be used to do calcaneal tunnel in clinical practice during anatomic ligament reconstruction for chronic ankle instability.

MRI of the cervical spinal cord predicts respiratory dysfunction in ALS

For patients with amyotrophic lateral sclerosis (ALS), the primary therapeutic goal is to minimize morbidity. Non-invasive ventilation improves survival. We aim to assess whether Magnetic Resonance Imaging (MRI) of the cervical spinal cord predicts the progression of respiratory disorders in ALS. Brain and spinal MRI was repeatedly performed in the SOD1^G86R mouse model, in 40 patients and in healthy controls. Atrophy, iron overload, white matter diffusivity and neuronal loss were assessed. In Superoxide Dismutase-1 (SOD1) mice, iron accumulation appeared in the cervical spinal cord at symptom onset but disappeared with disease progression (after the onset of atrophy). In ALS patients, the volumes of the motor cortex and the medulla oblongata were already abnormally low at the time of diagnosis. Baseline diffusivity in the internal capsule was predictive of functional handicap. The decrease in cervical spinal cord volume from diagnosis to 3 months was predictive of the change in slow vital capacity at 12 months. MRI revealed marked abnormalities at the time of ALS diagnosis. Early atrophy of the cervical spinal cord may predict the progression of respiratory disorders, and so may be of value in patient care and as a primary endpoint in pilot neuroprotection studies.

Hippocampal Deformations and Entorhinal Cortex Atrophy as an Anatomical Signature of Long-Term Cognitive Impairment: from the MCAO Rat Model to the Stroke Patient

Stroke patients have an elevated risk of developing long-term cognitive disorders or dementia. The latter is often associated with atrophy of the medial temporal lobe. However, it is not clear whether hippocampal and entorhinal cortex atrophy is the sole predictor of long-term post-stroke dementia. We hypothesized that hippocampal deformation (rather than atrophy) is a predictive marker of long-term post-stroke dementia on a rat model and tested this hypothesis in a prospective cohort of stroke patients.Male Wistar rats were subjected to transient middle cerebral artery occlusion and assessed 6 months later. Ninety initially dementia-free patients having suffered a first-ever ischemic stroke were prospectively included in a clinical study. In the rat model, significant impairments in hippocampus-dependent memories were observed. MRI studies did not reveal significant atrophy of the hippocampus volume, but significant deformations were indeed observed-particularly on the ipsilateral side. There, the neuronal surface area was significantly lower in ischemic rats and was associated with a lower tissue density and a markedly thinner entorhinal cortex. At 6 months post-stroke, 49 of the 90 patients displayed cognitive impairment (males 55.10%). Shape analysis revealed marked deformations of their left hippocampus, a significantly lower entorhinal cortex surface area, and a wider rhinal sulcus but no hippocampal atrophy. Hence, hippocampal deformations and entorhinal cortex atrophy were associated with long-term impaired cognitive abilities in a stroke rat model and in stroke patients. When combined with existing biomarkers, these markers might constitute sensitive new tools for the early prediction of post-stroke dementia.

Evaluation of Serum 3-Bromotyrosine Concentrations in Dogs with Steroid-Responsive Diarrhea and Food-Responsive Diarrhea

Background

The clinical usefulness of serum 3‐BrY concentrations for subclassifying dogs with food‐responsive diarrhea (FRD) and steroid‐responsive diarrhea (SRD) has not been studied.

Hypothesis/Objectives

To compare serum 3‐BrY concentrations in dogs with FRD, dogs with SRD, and healthy control dogs.

Animals

38 dogs with FRD, 14 dogs with SRD, and 46 healthy dogs.

Methods

Prospective study. Measurement of 3‐BrY concentration in serum samples was performed by gas chromatography/mass spectrometry.

Results

There was no association of peripheral eosinophilia in dogs with FRD, SRD, and healthy control dogs (P = 0.069). There was no significant correlation between peripheral eosinophil counts and serum 3‐BrY concentrations (ρ = −0.15, P = 0.13). Serum 3‐BrY concentrations in dogs with SRD (median [range] = 3.27, 0.9–26.23 μmol/L) were significantly higher than in dogs with FRD (median [range] = 0.99, 0.62–8.82 μmol/L; P = 0.007) or in healthy dogs (median [range] = 0.62, 0.62–1.79 μmol/L; P < 0.001). Also, serum 3‐BrY concentrations in dogs with FRD were significantly higher than in healthy dogs (P = 0.025). There was no significant correlation between the canine chronic enteropathy clinical activity index and serum 3‐BrY concentrations (ρ = 0.17, P = 0.23).

Conclusions and Clinical Importance

Measurement of serum 3‐BrY concentrations, but not the peripheral eosinophil count, is helpful for detecting dogs with SRD and FRD.

A systematic review of transcranial magnetic stimulation use for treating autistic spectrum disorders: Preliminary results

Autistic spectrum disorders (ASD) are a group of neurodevelopmental disorders that manifest as deficits in social communication and interaction, and restricted, repetitive behaviors and interests. ASD affect at least 1% of the population and are associated with lifelong disability and early death. There are no effective biological treatments for ASD, although non-invasive neuromodulation has sparked great interest as a possibly useful therapeutic approach. Here, we present preliminary results of a systematic review on the effectiveness of transcranial magnetic stimulation (TMS) in ASD treatment. Using appropriate syntax we searched Pubmed, Web of Science, Science Direct, and Educational Resources Information Clearinghouse. Following standard PRISMA statement (Preferred Reporting Items for Systematic Reviews and Meta-analyses) procedures, we selected 12 eligible studies, comprising four controlled and four uncontrolled trials on the effects of TMS on ASD core symptoms, and 9 controlled and three uncontrolled trials on TMS effects on cognitive performance in ASD. The 12 studies totaled 233 subjects. Although combined effect sizes favor TMS in all fours groups of studies, conclusions are limited by the high study heterogeneity. Furthermore, only three of the controlled studies used sham TMS as the control intervention, and only two studies followed up the therapeutic effects after the last TMS session. Side effects, none of them serious, occurred in 6.4% of treated subjects. Our main conclusion is that there is currently little evidence that sustains the commercial offer of TMS for treating ASD. Better-designed studies are badly needed to fully elucidate the role of TMS in the treatment of ASD.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Hyperhomocysteinemia in Greyhounds and its Association with Hypofolatemia and Other Clinicopathologic Variables

Background

Folate and cobalamin are essential cofactors for homocysteine (HCY) metabolism. Hyperhomocysteinemia, a multifactorial condition, may reflect B vitamin deficiency and is associated with increased risk of cardiovascular disease, thrombosis, and neurodegenerative and chronic gastrointestinal diseases in humans. Hyperhomocysteinemia has been reported in Greyhounds with suspected chronic enteropathy.

Objectives

To evaluate the frequencies of and the association between hypofolatemia and hyperhomocysteinemia in Greyhounds.

Animals

Data and serum samples from 559 Greyhounds.

Methods

Nested case‐control study. The frequency of hypofolatemia in Greyhounds was determined by a laboratory database search. The relationship between hyperhomocysteinemia (measured by gas chromatography‐mass spectrometry) and hypocobalaminemia and hypofolatemia was evaluated, and its frequency compared between healthy Greyhounds and Greyhounds with thrombosis or chronic diarrhea.

Results

Hypofolatemia was identified in 172 of 423 (41%) Greyhounds and was more common in hypo‐ than in normocobalaminemic dogs (49% vs. 35%; P = .0064). Hyperhomocysteinemia was detected in 53 of 78 (68%) of Greyhounds, being more common in hypo‐ than in normofolatemic dogs (88% vs. 59%; P = .0175). All healthy Greyhounds, 21 of 30 (70%) of dogs with chronic diarrhea and 6 of 8 (75%) of those with thrombosis, were hyperhomocysteinemic. Serum HCY concentrations were inversely correlated with serum folate concentration (ρ = −0.28; P = .0386) and were positively associated with serum albumin concentration (ρ = 0.66; P = .0022).

Conclusions and Clinical Relevance

Hyperhomocysteinemia occurs frequently in the Greyhound population. Its association with hypofolatemia suggests decreased intracellular availability of B vitamins, but the functional implications warrant further investigation. Hyperhomocysteinemia in Greyhounds potentially may serve as a spontaneous canine model to further investigate hyperhomocysteinemia in humans.

The value of magnetic resonance imaging as a biomarker for amyotrophic lateral sclerosis: a systematic review

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a fatal, rapidly progressive neurodegenerative disease that mainly affects the motor system. A number of potentially neuroprotective and neurorestorative disease-modifying drugs are currently in clinical development. At present, the evaluation of a drug's clinical efficacy in ALS is based on the ALS Functional Rating Scale Revised, motor tests and survival. However, these endpoints are general, variable and late-stage measures of the ALS disease process and thus require the long-term assessment of large cohorts. Hence, there is a need for more sensitive radiological biomarkers. Various sequences for magnetic resonance imaging (MRI) of the brain and spinal cord have may have value as surrogate biomarkers for use in future clinical trials. Here, we review the MRI findings in ALS, their clinical correlations, and their limitations and potential role as biomarkers.

METHODS

The PubMed database was screened to identify studies using MRI in ALS. We included general MRI studies with a control group and an ALS group and longitudinal studies even if a control group was lacking.

RESULTS

A total of 116 studies were analysed with MRI data and clinical correlations. The most disease-sensitive MRI patterns are in motor regions but the brain is more broadly affected.

CONCLUSION

Despite the existing MRI biomarkers, there is a need for large cohorts with long term MRI and clinical follow-up. MRI assessment could be improved by standardized MRI protocols with multicentre studies.

Does Biolox Delta ceramic reduce the rate of component fractures in total hip replacement?

Biolox Delta ceramic has been optimized with nano-sized, yttria-stabilized tetragonal zirconium and strontium oxide to help limit cracking propagation. Although its mechanical properties are better than those of earlier generation ceramics, existing data on this material are limited, thus the goals of this study were to determine: 1) the remaining rate of implant fracture; 2) the ideal combination of head diameter and component position. Hypothesis. We hypothesized that the use of the ceramic composite Biolox Delta had reduced the risk of implant fracture. Materials and methods. The bibliographic search (in Pubmed database with the key words «ceramic fracture» and «total hip prosthesis ») identified 46 articles on fractures in third or fourth generation ceramic components, including 5 involving Biolox Delta. Manufacturer's data and ANSM (Agence nationale de sécurité du médicament et des produits de santé) (National Agency for Safety of Drugs and Medical Products) reports were compared with the few clinical cases published in the literature. Results. According to the manufacturer (CeramTec GmbH, Plochingen, Germany), the use of Biolox Delta ceramic has reduced the rate of femoral head fractures to 0.003% compared to 0.021% with alumina ceramic. The fracture rate of liners has remained stable, at approximately 0.03%. The number of ANSM reports confirmed these tendencies. The rate of head component fractures decreases as the head diameter increases. The quality of impaction on the morse taper (cleanliness of the taper, insertion along the axis) plays an important role. Although it is generally only available for cup sizes above 50mm, a 36-mm head diameter seems to be optimal because it prevents impingement between the cup rim and the neck of the stem, without increasing micro-separation with larger diameters. Conclusion. Although Biolox Delta ceramic is more resistant to fractures than alumina ceramic, it can be fractured under suboptimal implantation conditions including edge loading. Its use requires the same precautions as other hard-on-hard bearings and requires special attention to cup position, insertion on or in morse tapers and adjustment of leg length.

LEVEL OF EVIDENCE

V expert's opinion.

Risk of osteoarthritis secondary to partial or total arthrodesis of the subtalar and midtarsal joints after a minimum follow-up of 10 years

INTRODUCTION

The goal of this retrospective, multicentre study was to evaluate the long-term outcomes in patients who have undergone partial or total arthrodesis of the subtalar and midtarsal joints.

HYPOTHESIS

Secondary osteoarthritis of the adjacent joints can negatively affect the outcomes more than 10 years after these fusion procedures.

MATERIAL AND METHODS

The outcomes of 72 fusions (total: 22; partial: 50) performed between 1981 and 2002 were evaluated using the Maryland Foot Score (MFS), self-evaluation questionnaire and three weight-bearing X-ray views (Meary's with cerclage wire around heel, lateral and dorsoplantar). The average follow-up was 15 ± 5 years (range 10-31).

RESULTS

There were two deep infections that resolved after lavage and antibiotics therapy. There were 21 early complications (10 complex regional pain syndrome, 7 delayed wound healing, 2 superficial infections, 2 venous thrombosis) that all resolved. There were five cases of non-union (6.9%) that healed after being re-operated. After five years, secondary osteoarthritis led to the fusion being extended to the tibotalar joint (1 case) and midtarsal joint (1 case). At the last follow-up, the average MFS was 71.5 (range 25-100). Patient deemed the result as either excellent (10%), very good (9%), good (55%), poor (19%) or bad (7%). Pain at the last follow-up was present in 84% of cases. The rear-foot was normally aligned in 45% of cases, varus aligned in 22% and valgus aligned in 33%. The MFS was significantly better in patients with normal alignment. Patients with neurological foot disorders had significantly more preoperative (80% cavovarus) and postoperative foot deformity (P<0.05). At the last follow-up, the rate of secondary osteoarthritis in the surrounding joints was elevated: 73% tibiotalar, 58.3% subtalar, 65.8% talonavicular, 53.5% calaneocuboid. The presence of osteoarthritis was not correlated with pain or lower MFS. However there was significantly more pain at last follow-up than at 12 months postoperative and two fusions were required in patients with secondary osteoarthritis.

CONCLUSION

Although partial or total arthrodesis of the subtalar and midtarsal joints is a reliable procedure, it induces secondary osteoarthritis. Even though it seems to be well tolerated more than 10 years after the initial procedure, this possibility must be discussed with young, active patients.

LEVEL OF EVIDENCE

IV, retrospective study.

Acoustic analog to the dynamical Casimir effect in a Bose-Einstein condensate

We have modulated the density of a trapped Bose-Einstein condensate by changing the trap stiffness, thereby modulating the speed of sound. We observe the creation of correlated excitations with equal and opposite momenta, and show that for a well-defined modulation frequency, the frequency of the excitations is half that of the trap modulation frequency.