The trend of percutaneous and open surgical procedures for peripheral arteriovenous malformations in the National Health Service England

INTRODUCTION

This study aimed to assess the trend of percutaneous and open surgical procedures for peripheral arteriovenous malformations (AVMs) performed in NHS hospitals in England between 2012 and 2018.

METHODS

Hospital Episode Statistics (HES) is a freely available data warehouse that represents the whole population of England served by the NHS. Data from the HES database was obtained and analysed for all hospital episodes between 2012 and 2018 for the total number and trend of 'primary diagnosis', and 'primary procedures and interventions' identified for peripheral AVMs.

RESULTS

Over the period studied, there was an increase in the total number of admissions for peripheral AVMs; total primary diagnosis increased from 2242 to 2857 per year. Open surgery remained more commonly performed than percutaneous procedures throughout the studied period. However, the overall percentage of primary procedures and interventions being percutaneous in this period increased from 29.8% to 41.0% per year. The increase in the number of percutaneous procedures per year seemed to occur in both children (from 43 to 124) and adults (from 408 to 492) over the course of the study period.

CONCLUSIONS

This study concluded that open surgery remained the most commonly performed primary procedure for peripheral AVMs, although there was an increasing trend for percutaneous procedures in NHS hospitals in England. The increase in the number and percentage of percutaneous procedures for peripheral AVMs was likely to have significant resource implications for the provision of care for patients with peripheral AVMs in NHS hospitals.

522 Early Follow-Up Quality of Life and Mental Health of Patients with Congenital Vascular Malformations Cared for in a Multi-Disciplinary Specialist Center

Aim

To evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) receiving care by a single multi-disciplinary specialist center

Method

This was a prospective observational study. All patients with CVM who received care (supportive treatment only, open surgery, targeted pharmacological therapy, embolosclerotherapy), and had follow-up, between February 1st 2018 and January 31st 2020 were included. The health-related QoL, pain, and mental health were assessed with validated questionnaires: SF-36, VAS-P and HADS. The CVM were categorized into types – low-flow (LFVM) and high-flow (HFVM), and anatomical locations. Paired t-test was used for all analyses. P<0.05 were considered significant.

Results

110 patients (85 LFVM and 25 HFVM) with a mean age of 36.9 years were included. Significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both P = 0.01) in all patients. However, only patients with HFVM reported significant improvement in the bodily pain domain of SF-36 (P=0.002) and VAS-P (P = 0.02). Patients who received supportive treatment only reported significant improvement in mental health (P=0.004) and social functioning (P=0.03) domains of SF-36. Meanwhile, patients treated with embolo-sclerotherapy reported significant improvement only in VAS-P (P=0.02). Patients who received targeted pharmacological therapy reported no significant early changes.

Conclusions

The effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research is required to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

518 Efficacy and Safety of Embolo-Sclerotherapy of Low-Flow Vascular Malformations Based on the Experience from a Single Specialist Centre

Aim

To evaluate the efficacy and safety of embolo-sclerotherapy (EST) of low-flow vascular malformations (LFVM) in a specialist vascular anomalies centre.

Method

All patients with LFVM who underwent EST from 01 January 2015–31 December 2019 were retrospectively reviewed. All ESTs were performed with foam STS 3%, ethanol, coils and/or other substances e.g., triamcinolone. LFVMs were grouped according to Puig's classification. The outcome measures were treatment effects and complications. Continuous variables were compared using analysis of variance (ANOVA) F test. Other discrete variables were compared using Chi-squared tests. P<0.05 were considered significant.

Results

A total of 207 patients, with a mean age of 32 years (range 1–71 years) were included. The use of EST with foam STS was significantly lower for type I LFVM (61.8%) compared to others (p<0.001). However, significantly higher type I LFVM (26.5%) were treated with surgery than EST (p<0.001). Overall, outcome categories were significantly different across all types of LFVM (p<0.001), with more discharges for Type I (52.9%) LFVMs but more failure to follow-up in patients with Type II (24.5%) LFVM. EST complications was significantly higher with type I (14.7%) LFVMs (p=0.030). The doses of STS in the first procedure were significantly different across all types of LFVM (p<0.001) with most type I LFVM patients receiving ≤2ml.

Conclusions

EST particularly with foam sclerotherapy is clinically effective and safe for patients with LFVM especially in those with Puig's type I and II lesions. This classification may provide an important guide to volume of sclerosant required and the potential success rate.

O064 Early follow-up quality of life and mental health of patients with congenital vascular malformations cared for in a multi-disciplinary specialist center

Introduction

To evaluate the early follow-up quality of life (QoL), pain and mental health of patients with congenital vascular malformation (CVM) receiving care by a single multi-disciplinary specialist centre

Methods

All patients with CVM who received care (supportive treatment only, open surgery, targeted pharmacological therapy, embolosclerotherapy), and had follow-up, between 1 February 2018 and 31 January 2020 were included. The health-related QoL, pain, and mental health were assessed with validated questionnaires: SF-36, VAS-P and HADS. The CVM were categorized into types – low-flow (LFVM) and high-flow (HFVM), and anatomical locations. Paired t-test was used for all analyses. Differences were considered significant at P<0.05.

Results

110 patients (85 LFVM and 25 HFVM) with a mean age of 36.9 years were included. Significant improvement was found in the bodily pain domain of SF-36 and VAS-P (both P = 0.01) in all patients. However, only patients with HFVM reported significant improvement in the bodily pain domain of SF-36 (P=0.002) and VAS-P (P = 0.02). Patients who received supportive treatment only reported significant improvement in mental health (P=0.004) and social functioning (P=0.03) domains of SF-36. Meanwhile, patients treated with embolosclerotherapy reported significant improvement only in VAS-P (P=0.02). Patients who received targeted pharmacological therapy reported no significant early changes.

Conclusion

The effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research is required to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Take-home message

The effects of care on early follow-up QoL, pain and mental health of patients with CVM were heterogenous. Future research is required to understand the various factors that affect the QoL and mental health of these patients, as well as the holistic approaches to manage them.

Vascular inflammation in patients with obstructive sleep apnoea and coronary artery disease shown on coronary computed tomography angiography attenuation

Funding Acknowledgements

Type of funding sources: None.

Introduction

Obstructive sleep apnoea (OSA) is associated with increased plaque burden in coronary artery disease (CAD), but the role of vascular inflammation in this relationship is unclear. Coronary computed tomography angiography (CTA) enables surrogate assessment of systemic inflammation via subcutaneous adipose tissue attenuation (ScAT-a), and of coronary inflammation via epicardial adipose tissue volume and attenuation (EAT-v and EAT-a) and pericoronary adipose tissue attenuation (PCAT-a).

Purpose

To investigate whether vascular inflammation is increased in patients with severe OSA and high plaque burden.

Methods

Patients with clinically indicated polysomnography and coronary CTA were included. Severe OSA was classified as apnoea/hypopnoea index (AHI) >30. High plaque burden was defined as a CT-Leaman score (CT-LeSc) >8.3. Patients with both severe OSA and high plaque burden were defined as ‘Group 1’, all other patients were classified as ‘Group 2’. ScAT-a, EAT-a, EAT-v and PCAT-a were assessed on semi-automated software.

Results

A total of 91 patients were studied (59.3 ± 11.1 years). Severe OSA was associated with high plaque burden (p = 0.02). AHI correlated with CT-LeSc (r = 0.24, p = 0.023). Group 1 had lower EAT-a and PCAT-a compared to Group 2 (EAT-a: -87.6 vs. -84.0 HU, p = 0.01; PCAT-a: -90.4 vs. -83.4 HU, p < 0.01). However, among patients without high plaque burden, EAT-a was increased in patients with severe OSA versus mild-moderate OSA (-80.3 vs. -84.0 HU, p = 0.020). On multivariable analysis, EAT-a independently associated with severe OSA and high plaque burden (p < 0.02), and PCAT-a associated with severe OSA and high plaque burden, and hypertension (all p < 0.01).

Conclusions

EAT attenuation is decreased in patients with severe OSA and high plaque burden but increased in patients with severe OSA and low plaque burden. These divergent results suggest coronary inflammation may be increased in OSA independent of CAD, but larger studies are required to validate these findings.

Outcomes after percutaneous coronary intervention (PCI) in patients with prior coronary artery bypass grafting (cabg)

Background

In patients with prior CABG requiring subsequent PCI there is uncertainty whether bypass grafts or native coronary arteries should be targeted.

Methods

We analysed data from 2,764 patients with prior CABG in the Melbourne Interventional Group registry (2005–2018), divided into two groups: those undergoing PCI to a native vessel (n=1,928) and those with PCI to a graft vessel (n=836).

Results

Patients with a graft vessel PCI were older, had more high-risk clinical characteristics (prior MI, heart failure, ejection fraction <50%, renal impairment, peripheral and cerebrovascular disease), and high-risk procedural features (ACC/AHA types B2/C lesions). However, patients in the native vessel group were more likely to have PCI to a chronic total occlusion. The majority of graft PCI were to saphenous vein grafts (84%), with 10% to radial and 6% to LIMA/RIMA grafts. Distal embolic protection devices were used in 30% of graft PCI. Patients with graft PCI had higher rates of no reflow (6.3% vs. 1.5%; p<0.001), coronary perforation (p=0.016) and inpatient stent thrombosis (p=0.028). However, 30-day mortality and major adverse cardiovascular and cerebrovascular events (MACCE) were similar. Unadjusted long-term mortality (median follow up 4.8 years) was higher in patients who had undergone a graft PCI (44% vs. 32%, p<0.001), but following Cox proportional hazards modelling, PCI vessel type was not a predictor of long-term mortality (HR 1.13; 95% CI 0.96–1.33, p=0.14).

Conclusions

Early clinical outcomes and risk-adjusted long-term mortality are similar for patients with prior CABG undergoing PCI to a native vessel or a bypass graft.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): The Alfred Hospital

No dynamic changes in plasma ACE2 activity in patients with acute coronary syndrome

Background

Angiotensin converting enzyme 2 (ACE2) is expressed in the human myocardium and blood vessels and degrades the vasoconstrictor peptide angiotensin (Ang) II. Plasma ACE2 activity is elevated in patients with cardiovascular disease (CVD) and is a predictor of major adverse cardiovascular events (MACE) in obstructive coronary artery disease. However, it is unknown whether acute coronary syndrome (ACS) causes dynamic changes in plasma ACE2 activity.

Purpose

We investigated dynamic changes in serial troponin-T and plasma ACE2 activity in patients presenting with ACS who underwent invasive coronary angiography (ICA).

Methods

Consecutive patients admitted with ACS from October-November 2019 were screened. Those meeting the Fourth Universal Definition of Myocardial Infarction who had both ICA and serial troponin-T testing were included. The study was approved by the hospitals Human Research Ethics Committee. All patients had routine plasma samples taken over 3 time-points for measurement of troponin-T; the same sample was used to measure plasma ACE2 activity. Catalytic ACE2 activity was measured using a validated, sensitive quenched fluorescent substrate-based assay. Serial median troponin and ACE2 activity levels were analysed using the Friedman test for repeated measures.

Results

Forty-nine patients were included. The mean age of participants was 63.9±11.0 years, and 36 (74%) patients were male. Overall, 16 (36%) patients presented with ST-elevation myocardial infarction (STEMI) and 29 (74%) with non-ST-elevation myocardial infarction (NSTEMI). Twenty-nine (59%) patients had a history of hypertension and 14 (29%) a history of ischaemic heart disease; 13 (27%) with priorMI, 11 (22%) had previous PCI and 2 (4%) had prior coronary artery bypass grafting. Over the 3 time points, there was a clear rise in median troponin-T levels representing myocardial injury (p<0.001), with no change in median plasma ACE2 activity (p=0.23, table 1). There was no difference in median ACE2 activity in those presenting with STEMI vs. NSTEMI (6.9 [2.1–9.5] vs. 6.0 [1.8–12.1], p=0.87), nor in those who underwent PCI to a culprit lesion compared to those who did not have a culprit lesion stented (5.8 [0.9–10.5] vs. 7.3 [2.8–14.9], p=0.37).

Conclusions

Patients with ACS had higher plasma ACE2 levels compared to levels previously reported in healthy controls. There were no dynamic changes in ACE2 activity in the setting of ACS, despite a significant rise in troponin-T. These results suggest that plasma ACE2 levels reflect underlying endothelial dysfunction rather than acute myocardial injury or infarction. Studies are now underway to assess if plasma ACE2 activity in ACS predicts MACE.

Funding Acknowledgement

Type of funding sources: None. Table 1

1286 3D Printing of Aortic Valve Scaffolds for Heart Valve Regeneration

Introduction

Valvular heart disease (VHD) has been commonly described as the forgotten epidemic, with an estimated global prevalence of 2.5%. Current heart valve replacement therapies only partially offer a solution to the problem. In recent years, synthetic polymers have been explored due to their diversity allowing tailor-picking of essential traits, such as chemical properties, physical properties, and degradation states. This project investigated the feasibility and mechanical properties of reverse three-dimensional printing of biodegradable scaffolds for heart valve regeneration.

Method

Aortic valve dimensions at an average of 100mmHg were used for the computer aided design of the valves. Aortic valve scaffolds were fabricated using the 3D-TIPs reverse printing technique. Infill densities of 30%, 40% or 50% were used. Printed polymer scaffolds were coated in gelatine solution and compared using static tensile tests. Static strength and elasticity of coated and uncoated valves were compared.

Results

At 25%, 50% and 100% strain, significantly different elastic properties in favour of coated scaffolds between coated and uncoated valves was observed. Coated valves displayed greater strength than uncoated valves (p > 0.05). Computer aided design (CAD) software designed anatomically accurate scaffolds, but poor polymer coagulation was observed on the valve cusps.

Conclusions

The reverse-printing 3D-TIPS procedure successfully produces heart valve scaffolds which present architectural similarities to the naïve mitral valve, however, dimensions of the valves ought to be reassessed. Gelatine-coated valves exhibit greater elastic and tensile properties. A further understanding of cellular interactions on the polymer scaffold, in particular in vivo studies, are required for the continuity of future study.

1258 Computational Modelling Of 3D Printed Scaffolds for Heart Valve Regeneration

Aim

Prosthetic heart valve replacement remains the gold standard treatment for valvular heart disease. However, its durability is limited and there is thus a need to develop an understanding of the feasibility of alternative replacement therapies. 3-dimensional printing of heart valves has been explored due to its patient-specific design and control of desired biomechanical properties. Computational studies of the synthetic valves will contribute to optimisation of designs, as well as improved understanding of the biomechanical behaviour of the complex structures.

Method

Aortic valve dimensions at an average of 100mmHg were used for the computerised design of the valves. Fine Element Analysis modelling generated computational experiments alongside predicted results. Simulated radial pressures tests were conducted at pressures from 0mmHg to 140mmHg and compression tests were conducted at displacement levels between 0-10mm. A Young’s modulus of 0.5 MPa was used. All simulations were conducted in a quasi-static manner.

Results

As the radial pressure on the valves increased, the Mises stresses increased. The maxium Mises stress of the heart valve was 0.09MPa and 0.13MPa under the pressures of 90mmHg and 140mmHg respectively. As valve displacement increased, the Mises stress of the heart valves proportionally rose. In simulated radial pressures tests, the compressive force was 0.19N at 1mm compressive displacment and 1.8N at 10mm compressive displacment.

Conclusions

The simulations demonstrated that 3D-printed heart valve scaffolds can withstand simulated radial pressure and compression tests. A further mechanical tests of the printed scaffold and understanding of its response to hemodynamic dynamic flow is required for the continuity of further study.

P103 Impact of the COVID-19 pandemic on the sleep of patients of a multidisciplinary sleep clinic

Introduction

This study aimed to assess the impact of the COVID-19 pandemic on the sleep of adult patients of a multidisciplinary sleep clinic.

Methods

Patients were invited to complete online surveys: Survey 1 in October 2020 (increased COVID-19 restrictions) followed by Survey 2 in February 2021 (after easing of restrictions for a COVIDSafe summer).

Results

Of the 746 patients invited to participate, 73 completed and 8 partially returned Survey 1 (mean age 50.1 years, range 21–83 years, 58% female). Subsequently, 46 completed and 5 partially answered Survey 2. In Survey 1, 22/74 (29.7%) reported reduced sleep quantity and 31/75 (41.3%) indicated worse sleep quality compared with prior to the pandemic. In Survey 2, 33/46 (71.7%) described unchanged sleep quantity whilst 5/46 (10.9%) reported increased sleep quantity since easing COVID-19 restrictions. 36/46 (78.3%) indicated unchanged sleep quality whereas 5/46 (10.9%) described improved sleep quality since easing restrictions. However, 9/46 (19.6%) reported that their sleep remained worse compared with pre-pandemic. For patients who completed both surveys, there was no significant change in Insomnia Severity Index scores (Survey 1 mean 13.6, Survey 2 mean 12.9, mean difference -0.67 [95%CI -2.02, 0.68], p=0.32) or PROMIS Sleep-Related Impairment 8a T-scores (Survey 1 mean 59.0, Survey 2 mean 59.5, mean difference 0.44 [95%CI -1.55, 2.42], p=0.66).

Discussion

The COVID-19 pandemic has negatively affected the sleep of 44% of patients. Following easing of restrictions, symptoms of insomnia and sleep-related impairment did not change significantly, and 19.6% reported that their sleep was not back to their pre-pandemic baseline.

P057 Virus aerosol propagation by CPAP is proportional to mask leak and can be prevented by use of a hood and air filtration system

Introduction

Nosocomial transmission of SARS-CoV-2 has caused significant morbidity/mortality in the COVID-19 pandemic. Because patients auto-emit aerosols containing viable virus, these aerosols can be further propagated when patients undergo certain treatments including continuous positive airway pressure (PAP) therapy. This study aimed to assess the degree of viable virus propagated from mask leak in a PAP circuit.

Methods

Bacteriophage PhiX174 (108copies/mL) was nebulised into a custom PAP circuit. Mask leak was systematically varied to 0, 7, 21, 28 and 42 L/min at the mask interface. Plates containing Escherichia coli assessed the degree of viable virus settling on surfaces around the room. In order to contain virus spread a ventilated headboard and high efficiency particulate air (HEPA) filter was tested.

Results

Increasing mask leak was associated with virus contamination in a dose response manner (χ2= 58.24, df=4, p<0.001). Clinically relevant levels of leak (≥21 L/min) were associated with virus counts equivalent to using PAP with a standard vented mask. Viable viruses were recorded on all plates (up to 3.86m from source). A plastic hood with HEPA filtration significantly reduced viable viruses on all plates. HEPA exchange rates of 170 and 470m3/hr eradicated all evidence of virus contamination.

Discussion

Mask leak from PAP circuits may be a major source of environmental contamination and nosocomial spread of infectious respiratory diseases. Subclinical levels of leak should be treated as an infectious risk. Cheap and low-cost patient hoods with HEPA filtration are an effective countermeasure.

O75: SINGLE CENTRE EXPERIENCE OF SIROLIMUS THERAPY IN HEAD AND NECK VASCULAR MALFORMATIONS

Introduction

To assess the efficacy and safety of Sirolimus in the treatment of low-flow head and neck (H&N) vascular malformations

Method

Patients who presented to our tertiary referral clinic were assessed for eligibility. Suitable patients were commenced on Sirolimus at 0.8 mg/m2, administered orally twice daily, which was approved by our trust Drug and Therapeutic Committee. Patients were reviewed on a monthly basis for a total of six months with an additional one-month review to check for effects upon ceasing treatment. Efficacy and safety were measured through functional and radiological response, laboratory investigations and quality of life questionnaire (36-Item Short Form Health Survey (SF-36), Hospital Anxiety and Depression Scale (HADS) and Visual Analogue Score for Pain (VAS-P)).

Result

Seven patients (mean age 39 years, range 23-65 years) were recruited. One patient did not complete treatment due to intolerable side effects. All patients had a partial response with no patients showing disease progression or complete response. All post-treatment MRI scans showed stable disease with five patients demonstrating a decrease in lesion volume. Five patients reported return of symptoms at one-month post review upon discontinuation of treatment. No statistical significance (P&gt;0.05) in all eight domains of SF-36, HADS, VAS-P and radiological vascular lesion volume between pre- and post-treatment. Most common reported side effects were mouth ulcers (n=2) and metabolic/laboratory abnormality (n=2)

Conclusion

Sirolimus is an effective and safe treatment for patients with complicated low-flow H&N vascular malformations. This provides an alternative treatment where interventional therapy is considered to be limited or challenging.

Take-home message

Sirolimus is an effective and safe treatment option for patients with complicated low-flow head and neck vascular malformations where interventional therapy is limited or challenging.

An absolute risk-guided approach to cardiovascular risk management within a chest pain clinic: the ARCPAC randomized trial

Background

The majority of patients attending chest pain clinics are found not to have a cardiac cause of their symptoms, but have a high burden of cardiovascular risk factors that may be opportunistically addressed. Absolute risk calculators are recommended to guide risk factor management, although it is uncertain to what extent these calculations may assist with patient engagement in risk factor modification.

Purpose

We sought to determine the usefulness of a proactive, absolute risk-based approach, to guide opportunistic cardiovascular risk factor management within a chest pain clinic.

Methods

This was a prospective, open-label, blinded-endpoint study in 192 enhanced risk (estimated 5-year risk ≥8%, based on Australian Absolute Risk Calculator) patients presenting to a tertiary hospital chest pain clinic. Patients were randomized to best practice usual care, or intervention with development of a proactive cardiovascular risk management strategy framed around a discussion of the individual's absolute risk. Patients found to have a cardiac cause of symptoms were excluded as they constitute a secondary prevention population. Primary outcome was 5-year absolute cardiovascular risk score at minimum 12 months follow up. Secondary outcomes were individual modifiable risk factors (lipid profile, blood pressure, smoking status).

Results

192 people entered the study; 100 in the intervention arm and 92 in usual care. There was no statistical difference between the two groups' baseline sociodemographic and clinical variables. The intervention group showed greater reduction in 5-year absolute risk scores (difference −2.77; p&lt;0.001), and more favourable individual risk factors, although only smoking status and LDL cholesterol reached statistical significance (table).

Conclusion

An absolute risk-guided proactive risk factor management strategy employed opportunistically in a chest pain clinic significantly improves 5-year cardiovascular risk scores.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Tasmanian Community Fund

Relationship between 'on-treatment platelet reactivity', shear stress, and micro-embolic signals in asymptomatic and symptomatic carotid stenosis

BACKGROUND

Assessment of 'high on-treatment platelet reactivity (HTPR)' could enhance understanding of the pathophysiology of first or recurrent vascular events in carotid stenosis patients on antiplatelet therapy.

METHODS

This prospective, multi-centre study assessed antiplatelet-HTPR status and its relationship with micro-emboli signals (MES) in asymptomatic vs. symptomatic ≥ 50-99% carotid stenosis. Platelet function/reactivity was assessed under 'moderately high shear stress' with the PFA-100^® and 'low shear stress' with VerifyNow^® and Multiplate^® analysers. Bilateral 1-h transcranial Doppler ultrasound of the middle cerebral arteries classified patients as MES + ve or MES - ve.

RESULTS

Data from 34 asymptomatic patients were compared with 43 symptomatic patients in the 'early phase' (≤ 4 weeks) and 37 patients in the 'late phase' (≥ 3 months) after TIA/ischaemic stroke. Median daily aspirin doses were higher in early symptomatic (225 mg; P < 0.001), but not late symptomatic (75 mg; P = 0.62) vs. asymptomatic patients (75 mg). There was a lower prevalence of aspirin-HTPR in early (28.6%; P = 0.028), but not late symptomatic (38.9%; P = 0.22) compared with asymptomatic patients (56.7%) on the PFA-100^®, but not on the VerifyNow^® or Multiplate^® (P ≤ 0.53). Early symptomatic patients had a higher prevalence of aspirin-HTPR on the PFA-100^® (28.6%) vs. VerifyNow^® (9.5%; P = 0.049), but not Multiplate^® assays (11.9%, P = 0.10). There was no difference in aspirin-HTPR prevalence between any symptomatic vs. asymptomatic MES + ve or MES - ve subgroup.

DISCUSSION

Recently symptomatic moderate-severe carotid stenosis patients had a lower prevalence of aspirin-HTPR than their asymptomatic counterparts on the PFA-100^®, likely related to higher aspirin doses. The prevalence of antiplatelet-HTPR was positively influenced by higher shear stress levels, but not MES status.

An evaluation of brigatinib as a promising treatment option for non-small cell lung cancer

Introduction: Brigatinib is a second-line inhibitor for the treatment of rearranged anaplastic lymphoma kinase (ALK) in lung cancer patients which has significant activity against brain metastases. This tyrosine kinase inhibitor (TKI) overcomes a wide range of ALK mutations which confer therapeutic resistance and is increasingly applied in first-line therapy due to improved benefit for patients compared to crizotinib, the current standard of care. Areas covered: The authors review the development and characteristics of brigatinib and discuss the optimal clinical use and sequence of the application of ALK inhibitors in patients progressing under therapy. Expert opinion: ALK-rearranged NSCLC can be treated with a broad range of approved and novel inhibitors at various stages of therapy, including the second-line therapeutic brigatinib. Besides this TKI, the second-line ALK inhibitors alectinib and ceritinib, as well as the third-line lorlatinib are approved for the treatment of ALK-positive NSCLC patients. The main challenge is to find sequences and combinations of ALK inhibitors which provide the best benefit for the patients.

Metrizamide Epidurography

The results are reported of lumbar epidurography in 110 patients suffering from low back pain. By using the water-soluble non-ionic contrast metrizamide, it has been possible to perform the examination on an outpatient basis. None of the patients has suffered from headache, nor any other complaint often associated with other diagnostic techniques which involve lumbar puncture. Epidurography is sufficiently accurate to be regarded as the examination of choice in the diagnosis of lumbar disc prolapse.

Identification of Sertoli cell-specific transcripts in the mouse testis and the role of FSH and androgen in the control of Sertoli cell activity

Background

The Sertoli cells act to induce testis differentiation and subsequent development in fetal and post-natal life which makes them key to an understanding of testis biology. As a major step towards characterisation of factors involved in Sertoli cell function we have identified Sertoli cell-specific transcripts in the mouse testis and have used the data to identify Sertoli cell-specific transcripts altered in mice lacking follicle-stimulating hormone receptors (FSHRKO) and/or androgen receptors (AR) in the Sertoli cells (SCARKO).

Results

Adult iDTR mice were injected with busulfan to ablate the germ cells and 50 days later they were treated with diphtheria toxin (DTX) to ablate the Sertoli cells. RNAseq carried out on testes from control, busulfan-treated and busulfan + DTX-treated mice identified 701 Sertoli-specific transcripts and 4302 germ cell-specific transcripts. This data was mapped against results from microarrays using testicular mRNA from 20 day-old FSHRKO, SCARKO and FSHRKO.SCARKO mice. Results show that of the 534 Sertoli cell-specific transcripts present on the gene chips, 85% were altered in the FSHRKO mice and 94% in the SCARKO mice (mostly reduced in both cases). In the FSHRKO.SCARKO mice additive or synergistic effects were seen for most transcripts. Age-dependent studies on a selected number of Sertoli cell-specific transcripts, showed that the marked effects in the FSHRKO at 20 days had largely disappeared by adulthood although synergistic effects of FSHR and AR knockout were seen.

Conclusions

These studies have identified the Sertoli cell-specific transcriptome in the mouse testis and have shown that most genes in the transcriptome are FSH- and androgen-dependent at puberty although the importance of FSH diminishes towards adulthood.

Electronic supplementary material

The online version of this article (10.1186/s12864-017-4357-3) contains supplementary material, which is available to authorized users.

Seasonal Abundance and Phenology of Halyomorpha halys (Hemiptera: Pentatomidae) on Different Pepper Cultivars in the Mid-Atlantic (United States)

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive stink bug (Hemiptera: Pentatomidae) introduced into the United States in the mid-1990s. Since its initial establishment, it has spread throughout the east coast as far south as Georgia, and as far north as New Hampshire. While information is available regarding H. halys behavior and life history in some crops, relatively little information is available for vegetables such as peppers. Key questions include understanding when H. halys enters pepper fields to feed and how best to predict infestations, what population levels create economic damage, and if peppers that vary in capsaicin levels also vary in susceptibility to attack. To answer these questions, replicated plots were set up across four mid-Atlantic states using three types of peppers: sweet bell, sweet banana, and hot chili. We found that there was no difference in the overall abundance of all life stages of H. halys on all pepper varieties tested. However, there were differences in bug density by site, but these differences did not translate to differences in the proportion of damaged fruit. The presence of adult H. halys is a better predictor of damage in banana peppers, whereas nymphs are a better predictor in bell pepper. In addition, across all sites, the presence of egg masses was low in pepper crops and densities of both adults and immatures tend to peak on pepper plants in early August. Altogether, this information can be used to help develop a pest management program in peppers that will reduce crop losses to this new devastating pest, while reducing the reliance on insecticides to manage this pest at the same time.

Vertebral Tortuosity Index in Patients with Non-Connective Tissue Disorder-Related Aneurysm Disease

OBJECTIVE

The vertebral tortuosity index (VTI) predicts increased risk of acute aortic events in patients with known genetic aortopathies. This study describes the VTI in a cohort of patients with non-connective tissue disorder-related large aneurysms.

METHODS

Hospital imaging records from July 2012 to March 2016 were interrogated to identify patients with aneurysmal disease who had undergone computed tomographic angiography that included imaging of vertebral arteries. A control group of consecutive patients undergoing carotid and vertebral imaging was also assessed. VTI was calculated using the formula: [(centre-line distance) / (straight-line distance)-1] ×100 for all patients, and statistical analysis undertaken to determine whether measured VTI was statistically different in patients of younger age, with larger aneurysms, or an acute presentation. Comparison was made with patients who had no aneurysm disease.

RESULTS

Sixty-five patients were identified with adequate imaging to assess the entire aorta, including vertebral arteries. The majority of patients were male (71%, 46/65) and mean age at the time of the CT scan was 71 years (SD 11.1 years). There were 11 patients under the age of 60 years in this cohort. The mean VTI was 33.17 (SD 20.43). There was no statistically significant difference between different territories of presentation (proximal vs. distal aneurysm, p=.94), age of patient (>60 years vs. <60 years, p=.2), or size of aneurysm (>6 cm vs. <6 cm, p=.09). Acuity of presentation was not predicted by a higher VTI (p=.69). The VTI in patients with aneurysms was higher than in patients without aneurysm disease (VTI = 16.1, p<.005) CONCLUSIONS: An elevated VTI is consistently present in patients with degenerative aneurysms and has potential as a universally available predictive measurement. However, the increased VTI in the older cohort without connective tissue disease may not carry the same predictive value for acute presentations as has been demonstrated in younger patients with a known genetic basis for their aortopathy.

Bone marrow fat content is correlated with hepatic fat content in paediatric non-alcoholic fatty liver disease

AIM

To investigate the relationship between bone marrow fat content and hepatic fat content in children with known or suspected non-alcoholic fatty liver disease (NAFLD).

MATERIALS AND METHODS

This was an institutional review board-approved, Health Insurance Portability and Accountability Act (HIPAA)-compliant, cross-sectional, prospective analysis of data collected between October 2010 to March 2013 in 125 children with known or suspected NAFLD. Written informed consent was obtained for same-day research magnetic resonance imaging (MRI) of the lumbar spine, liver, and abdominal adiposity. Lumbar spine bone marrow proton density fat fraction (PDFF) and hepatic PDFF were estimated using complex-based MRI (C-MRI) techniques and magnitude-based MRI (M-MRI), respectively. Visceral adipose tissue (VAT) and subcutaneous adipose tissue (SCAT) were quantified using high-resolution MRI. All images were acquired by two MRI technologists. Hepatic M-MRI images were analysed by an image analyst; all other images were analysed by a single investigator. The relationship between lumbar spine bone marrow PDFF and hepatic PDFF was assessed with and without adjusting for the presence of covariates using correlation and regression analysis.

RESULTS

Lumbar spine bone marrow PDFF was positively associated with hepatic PDFF in children with known or suspected NAFLD prior to adjusting for covariates (r=0.33, p=0.0002). Lumbar spine bone marrow PDFF was positively associated with hepatic PDFF in children with known or suspected NAFLD (r=0.24, p=0.0079) after adjusting for age, sex, body mass index z-score, VAT, and SCAT in a multivariable regression analysis.

CONCLUSION

Bone marrow fat content is positively associated with hepatic fat content in children with known or suspected NAFLD. Further research is needed to confirm these results and understand their clinical and biological implications.

Abnormal vocal cord movement in patients with and without airway obstruction and asthma symptoms

BACKGROUND

Abnormal vocal cord movements can cause laryngeal extrathoracic airway obstruction (often called vocal cord dysfunction - VCD) leading to asthma-like symptoms. These aberrant movements are characteristically present during inspiration and termed paradoxical vocal cord movement (PVCM). We have reported PVCM in up to 40% of severe asthmatics, but it is not known if PVCM is detectable in all patients with asthma-like symptoms and if the condition is more often associated with abnormal lung function.

OBJECTIVE

We hypothesized that PVCM is frequently associated with asthma symptoms accompanied by airflow limitation. Studies examined whether PVCM is solely linked to experiencing asthma symptoms, or if PVCM is related to airflow limitation and/or other disease characteristics.

METHODS

Patients with asthma symptoms were recruited from general practice and severe asthma clinics (n = 155). Pulmonary function measurements were conducted, asthma control and Nijmegen (dysfunctional breathing) questionnaires were administered and skin prick testing was carried out. PVCM was quantified using dynamic 320-slice computerized tomography of the larynx. Groups were divided into patients with FEV₁ ≥ 80% predicted or FEV₁ < 80% predicted and FEV₁ /FVC < 0.7. ATS/ERS definitions of severity were also applied and evaluated. Detection of PVCM in the groups was compared and analyses performed to identify features associated with PVCM.

RESULTS

Overall (n = 155), PVCM was detected in 42 cases (27.1%). Patients with FEV₁ < 80% predicted had PVCM more often (25/68, 36.8%) than individuals with normal spirometry (17/87, 19.5%; P = 0.016). PVCM was associated with older age (P = 0.003) and with Nijmegen scores > 20 (P = 0.04). Patients with FEV₁ < 80% predicted plus Nijmegen scores > 20 were more likely to have PVCM (OR = 9.3, P = 0.02).

CONCLUSIONS AND CLINICAL RELEVANCE

Paradoxical vocal cord movement is more often associated with asthma symptoms accompanied by airflow limitation and dysfunctional breathing. Further studies are needed to determine whether PVCM is induced by dysfunctional breathing practices and/or airway obstruction. How PVCM links with symptomatic asthma and VCD also requires evaluation.

Short-term Lipid-Lowering Treatment with Atorvastatin Improves Renal Function But Not Renal Blood Flow Indices in Patients with Peripheral Arterial Disease

Some studies have suggested that lipid lowering with statins exerts favorable effects on the progression of chronic kidney disease. Therefore, the authors assessed the effects of short-term atorvastatin treatment on biochemical markers of renal function and evaluated duplex indices of renal blood flow (RBF) in patients with peripheral arterial disease. Hyperlipidemic claudicants (n=18), aged 44-85 years, were treated for 8 weeks with 20 mg/day atorvastatin. Blood tests at baseline and after 8 weeks included serum fasting lipids, creatinine, urate, and cystatin C (a sensitive indicator of renal function) levels. RBF was also assessed (n=9) by measuring pulsatile and resistance duplex indices. As expected, there was a significant improvement in total cholesterol, low-density lipoprotein cholesterol, and triglycerides. There was also a significant (p<0.0001) fall in serum creatinine from 89 (58-125) to 79 µmol/L (54-119) and an increase in calculated creatinine clearance (CrCl) from 72 (40-129) to 80 mL/minute (47-138; p<0.0001). Serum cystatin C values decreased significantly (p=0.0002) from 1.04 (0.57-1.56) to 0.90 mg/L (0.47-1.47). There were no detectable changes in the RBF duplex indices. Treatment of stable claudicants with atorvastatin for 8 weeks was associated with improved renal function (as assessed by serum creatinine, cystatin C, and calculated CrCl) without changes in RBF. Further studies are required to identify the mechanisms involved in this phenomenon.

Calcification of a Synthetic Renovascular Graft in a Child

INTRODUCTION

Vascular grafts, especially in paediatric cases, need to be durable. Common failures such as thrombosis are well documented with research efforts directed towards them. However, there are lesser known causes of graft failure, such as graft calcification, and these also require further research focus.

REPORT

A paediatric case is described in which a synthetic renovascular graft, implanted for mid-aortic syndrome, became calcified, necessitating surgical intervention to resolve graft malfunction. Significant calcification in the limb of a bifurcated polyethylene terephthalate graft was found to be the cause of resistant stenosis and refractory hypertension. Histology conducted on the explanted limb showed the presence of multinuclear giant cells, indicating a chronic foreign body response.

DISCUSSION

Calcification of vascular grafts is probably more common than previously recognised. Stenosis typically resistant to angioplasty may result in the long term and thus leading to surgical intervention. In young children, this is suboptimal as these grafts need to last throughout adulthood. Explanted prosthetic grafts should be sent to specialist registries such as that in Strasbourg to be optimally assessed so that contributory factors can be identified.

A Comparison of Accuracy of Image- versus Hardware-based Tracking Technologies in 3D Fusion in Aortic Endografting

OBJECTIVES

Fusion of three-dimensional (3D) computed tomography and intraoperative two-dimensional imaging in endovascular surgery relies on manual rigid co-registration of bony landmarks and tracking of hardware to provide a 3D overlay (hardware-based tracking, HWT). An alternative technique (image-based tracking, IMT) uses image recognition to register and place the fusion mask. We present preliminary experience with an agnostic fusion technology that uses IMT, with the aim of comparing the accuracy of overlay for this technology with HWT.

METHOD

Data were collected prospectively for 12 patients. All devices were deployed using both IMT and HWT fusion assistance concurrently. Postoperative analysis of both systems was performed by three blinded expert observers, from selected time-points during the procedures, using the displacement of fusion rings, the overlay of vascular markings and the true ostia of renal arteries. The Mean overlay error and the deviation from mean error was derived using image analysis software. Comparison of the mean overlay error was made between IMT and HWT. The validity of the point-picking technique was assessed.

RESULTS

IMT was successful in all of the first 12 cases, whereas technical learning curve challenges thwarted HWT in four cases. When independent operators assessed the degree of accuracy of the overlay, the median error for IMT was 3.9 mm (IQR 2.89-6.24, max 9.5) versus 8.64 mm (IQR 6.1-16.8, max 24.5) for HWT (p = .001). Variance per observer was 0.69 mm(2) and 95% limit of agreement ±1.63.

CONCLUSION

In this preliminary study, the error of magnitude of displacement from the "true anatomy" during image overlay in IMT was less than for HWT. This confirms that ongoing manual re-registration, as recommended by the manufacturer, should be performed for HWT systems to maintain accuracy. The error in position of the fusion markers for IMT was consistent, thus may be considered predictable.

A review of the role of surgery for small cell lung cancer and the potential prognostic value of enumeration of circulating tumor cells

Small cell lung cancer (SCLC) is disseminated in the majority of patients at first presentation and, thus, treated with chemoradiotherapy. Despite initial high response rates, chemoresistance appears rapidly and results in a dismal prognosis. However, patients with limited cancer may exhibit better disease control upon surgical treatment. Correct staging is highly critical in the selection of those patients which are likely to benefit from surgery. Studies of the inclusion of surgery in the multimodal treatment of SCLC vary widely in number of patients, selection, treatment and follow-up. Nevertheless surgical therapy for confined SCLCs achieves favorable long-term survival compared to chemoradiotherapy, depending on a precise assessment of the degree of tumor dissemination. Recently, extremely high counts of circulating tumor cells (CTCs) were reported in patients with SCLC compared to other malignancies. In several studies the number of CTCs was found to constitute a prognostic parameter and a marker of response to therapy. Therefore, the assessment of CTCs as so-called "Liquid Biopsy" seems to constitute a more precise method to detect tumor dissemination earlier when compared to clinical staging. In conclusion, in the era of precision oncology enumeration and identification of CTCs of SCLC patients have the potential to help in the selection of patients most suitable for tumor surgery.

Increased thrombin generation potential in symptomatic versus asymptomatic moderate or severe carotid stenosis and relationship with cerebral microemboli

INTRODUCTION

The importance of thrombin generation in the pathogenesis of TIA or stroke and its relationship with cerebral microembolic signals (MES) in asymptomatic and symptomatic carotid stenosis has not been comprehensively assessed.

METHODS

Plasma thrombin generation parameters from patients with moderate or severe (≥ 50%) asymptomatic carotid stenosis were compared with those from patients with symptomatic carotid stenosis in the early (≤ 4 weeks) and late phases (≥ 3 months) after TIA or stroke in this prospective, pilot observational study. Thrombin generation profile was longitudinally assessed in symptomatic patients with data at each time point. Bilateral transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed whenever possible to classify patients as MES-positive or MES-negative.

RESULTS

Data from 31 asymptomatic, 46 'early symptomatic' and 35 'late symptomatic' patients were analysed. Peak thrombin (344.2 nM vs 305.3 nM; p = 0.01) and endogenous thrombin potential (1772.4 vs 1589.7; p = 0.047) were higher in early symptomatic than asymptomatic patients. Peak thrombin production decreased in symptomatic patients followed up from the early to late phase after TIA or stroke (339.7 nM vs 308.6 nM; p = 0.02). Transcranial Doppler ultrasound data were available in 25 asymptomatic, 31 early symptomatic and 27 late symptomatic patients. Early symptomatic MES-positive patients had a shorter 'time-to-peak thrombin' than asymptomatic MES-positive patients (p=0.04), suggesting a more procoagulant state in this early symptomatic subgroup.

DISCUSSION

Thrombin generation potential is greater in patients with recently symptomatic than asymptomatic carotid stenosis, and decreases over time following TIA or stroke associated with carotid stenosis. These data improve our understanding of the haemostatic/thrombotic biomarker profile in moderate-severe carotid stenosis.

Nanotopography and plasma treatment: redesigning the surface for vascular graft endothelialisation

INTRODUCTION

Vascular graft materials in clinical use, such as polytetrafluoroethylene (PTFE) and Dacron, do not endothelialise and have low patency rates. The importance of an endothelial cell layer on the luminal surface of a vascular graft is well-known with surface topography and chemistry playing an important role. The aim of this study was to investigate the potential of plasma treatment and topographical structures on the luminal graft surface to enhance the self-endothelialisation potential of a nanocomposite vascular graft.

METHODS

POSS-PCU is a polycarbonate urea urethane (PCU) with a nanoparticle, polyhedral oligomeric silsesquioxane (POSS) incorporated within it. Planar, microgrooved, and nanopit patterned polymer films were fabricated using photolithography, electron beam lithography, reactive ion etching, and replication by solvent casting. Films were then exposed to oxygen plasma treatment at different powers for a fixed time (40 W, 60 W, 80 W/60 seconds). Effects of plasma treatment were assessed using scanning electron microscopy, atomic force microscopy and water contact angle analysis. Human umbilical vein endothelial cell (HUVEC) proliferation and morphology were characterised using immunostaining, live/dead staining, and Coomassie blue staining.

RESULTS

Successful embossing of the micro- and nanostructures was confirmed. Oxygen plasma treatment of the different samples showed that increasing power significantly increased the hydrophilicity of the samples (p < .0001). Improved HUVEC adhesion was seen on plasma modified compared with untreated samples (p < .0001). Coomassie blue staining showed that after 5 days, cells started to form monolayers and live/dead staining showed the cells were viable. Immunostaining showed that HUVECs expressed nitric oxide synthase on all topographies with focal adhesions appearing more pronounced on nanopit surfaces, showing retention of morphology and function.

CONCLUSION

These encouraging results indicate a future important role for plasma treatment and nanotopography in the development of endothelialised vascular grafts.