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Aims The aims were to report the incidence and outcomes of transcatheter aortic valve implantation-infective endocarditis (TAVI-IE) from a high-volume TAVI centre in the United Kingdom, including how incidence varies relative to time from the procedure, and to assess the performance of modified Duke criteria in the diagnosis of TAVI-IE. Methods The retrospective, cohort study included all patients who underwent TAVI at Leeds Teaching Hospitals Trust during a 10-year period. Outcome measures were the incidence of TAVI-IE, the accuracy of the modified Duke criteria and the mortality rate. Results A total of 1337 patients were followed up for a median of 2.3 years. Thirteen patients (0.97%) were diagnosed with TAVI-IE, mean age of 81.3 years (SD 5.1 years). Four patients (30.8%) fulfilled modified Duke criteria for definite infective endocarditis. The remaining nine patients (69.2%) fulfilled the modified Duke criteria for possible infective endocarditis. In the majority (7/13; 53.8%) the causative organism was streptococcal. Cumulative incidence of TAVI-IE has risen in line with the number of patients living with TAVI prostheses, and cumulative number of TAVI-years. However, in relation to the number of 100 TAVI-years, the infection rate has remained low and static over the last 6 years. The in-hospital mortality rate was 38.5%, all attributable to TAVI-IE. Conclusion The incidence of TAVI-IE was 0.97%, with an associated all-cause mortality of 53.8%. The incidence relative to the number of TAVI-years has remained low and static in recent years. The modified Duke criteria have relatively low sensitivity in the diagnosis of TAVI-IE, meaning that a high index of suspicion is required.

Background Previous studies of outcomes in people who inject drugs (PWID) with infective endocarditis (IE) have often been retrospective, have had small sample sizes, and the duration of follow-up has been short and limited to patients who were operated on. Methods PWID treated for IE between 1 January 2006 and 31 December 2016 were identified from a prospectively collected database. PWID hospitalized with other infections acted as a novel comparison group. Outcomes were all-cause mortality, cause of death, relapse, recurrence, and reoperation. Results There were 105 episodes of IE in 92 PWID and 112 episodes of other infections in 107 PWID in whom IE was suspected but rejected. Survival at 30 days for the IE group was 85%, and 30-day survival following surgery was 96%. The most common pathogens were Staphylococcus species (60%) and Streptococcus species (30%). The surgical intervention rate was 47%. Survival for the IE group at 1, 3, 5, and 10 years was 74%, 63%, 58%, and 44%, respectively. This was significantly lower compared with the comparator group of other infections in PWID (P = .0002). Mortality was higher in patients who required surgery compared with those who did not (hazard ratio, 1.8 [95% confidence interval, .95–3.3]). The commonest cause of death was infection (66%), usually a further episode of IE (55%). Conclusions Although early survival was good, long-term life expectancy was low. This was attributable to ongoing infection risk, rather than other factors known to affect prognosis in PWID. Surgery conferred no long-term survival advantage. More efforts are needed to reduce reinfection risk following an episode of IE in PWID. While early survival for people who inject drugs (PWID) with infective endocarditis is good, long-term survival is poor due to ongoing infection risk. Surgery conferred no long-term survival advantage, so more efforts are needed to reduce reinfection risks for PWID.

Background Diagnostic codes from electronic health records are widely used to assess patterns of disease. Infective endocarditis is an uncommon but serious infection, with objective diagnostic criteria. Electronic health records have been used to explore the impact of changing guidance on antibiotic prophylaxis for dental procedures on incidence, but limited data on the accuracy of the diagnostic codes exists. Endocarditis was used as a clinically relevant case study to investigate the relationship between clinical cases and diagnostic codes, to understand discrepancies and to improve design of future studies. Methods Electronic health record data from two UK tertiary care centres were linked with data from a prospectively collected clinical endocarditis service database (Leeds Teaching Hospital) or retrospective clinical audit and microbiology laboratory blood culture results (Oxford University Hospitals Trust). The relationship between diagnostic codes for endocarditis and confirmed clinical cases according to the objective Duke criteria was assessed, and impact on estimations of disease incidence and trends. Results In Leeds 2006–2016, 738/1681(44%) admissions containing any endocarditis code represented a definite/possible case, whilst 263/1001(24%) definite/possible endocarditis cases had no endocarditis code assigned. In Oxford 2010–2016, 307/552(56%) reviewed endocarditis-coded admissions represented a clinical case. Diagnostic codes used by most endocarditis studies had good positive predictive value (PPV) but low sensitivity (e.g. I33-primary 82% and 43% respectively); one (I38-secondary) had PPV under 6%. Estimating endocarditis incidence using raw admission data overestimated incidence trends twofold. Removing records with non-specific codes, very short stays and readmissions improved predictive ability. Estimating incidence of streptococcal endocarditis using secondary codes also overestimated increases in incidence over time. Reasons for discrepancies included changes in coding behaviour over time, and coding guidance allowing assignment of a code mentioning ‘endocarditis’ where endocarditis was never mentioned in the clinical notes. Conclusions Commonly used diagnostic codes in studies of endocarditis had good predictive ability. Other apparently plausible codes were poorly predictive. Use of diagnostic codes without examining sensitivity and predictive ability can give inaccurate estimations of incidence and trends. Similar considerations may apply to other diseases. Health record studies require validation of diagnostic codes and careful data curation to minimise risk of serious errors. Electronic supplementary material The online version of this article (10.1186/s12916-019-1390-x) contains supplementary material, which is available to authorized users.

Introduction Intracardiac abscess complicates both native (NV-IE) and prosthetic valve infective endocarditis (PV-IE). Antibiotics alone rarely achieve source control, and if left untreated abscesses are usually fatal. Uncomplicated abscesses affecting the aortic valve can be treated with aortic valve replacement (AVR) with or without patching of the abscess cavity. With more extensive tissue destruction aortic root replacement (ARR) may be required. The optimal surgical approach is controversial, ARR using homograft valve conduits are reported to have lower re-infection rates and have been favoured in most cases of abscess affecting the aortic root. Aims We aimed to describe the characteristics, surgical technique chosen, complications and outcomes for patients with intracardiac abscess presenting over more than a decade. Methods Consecutive patients assessed between 01 January 2005 and 31 December 2017 were identified from a prospectively collected database used for service evaluation of IE care. We required patients to have Duke definite IE with evidence of intracardiac abscess on imaging or found at operation. We recorded patient demographics, affected structures, microbiology, complications of IE, operative details and outcomes. Results There were 68 episodes of intracardiac abscess occurring in 59 patients, of whom 44 (75%) were male, 10 (17%) were persons who inject drugs (PWID) and the mean age was 55.7 +/- 16.3 years. Affected structures were primarily the aortic (55) and mitral (17) valves. Thirty-one (53%) had NV-IE and 28 (47%) had PV-IE. Multiple aortic cusps were involved in 68%. Bacterial pathogens were mainly Streptococcus (26) and Staphylococcus (18) species, which were associated with NV-IE (p=0.009) and PV-IE (p=0.005) respectively. The most common complications were heart failure (44), heart block (12) and systemic emboli including stroke. Forty-four (75%) patients underwent surgery, 28 had AVR and 14 ARR. The 30-day surgical mortality rate was 10 (23%) and associated with infection with S. aureus (p=0.006) and higher Euroscore II (p=0.03). No other operative factors were associated with survival including the timing of surgery and whether AVR or ARR was undertaken. During long-term follow up there were 9 episodes of re-infection which did not differ between AVR and ARR. The all-cause mortality in operated patients was 34%, 41% and 66% at 1, 5 and 10 years, respectively and the cause of death was due to IE and its complications in 91%. Discussion Abscess formation in IE is associated with high early and late mortality, 25% of patients were not fit for surgery due to prohibitively high preoperative risk. The findings presented here support an individualised approach to surgical technique depending on the results of preoperative imaging and operative findings. A third of patients required complex aortic root surgery, usually in the context of PV-IE. Surgical centres should have the skills and materials to undertake ARR in this high-risk setting. Conflict of Interest None

OBJECTIVES: Surgery is often required for acute infective endocarditis (IE) to repair or replace damaged heart valves. Traditionally, long courses of antibiotic treatment have been prescribed after surgery for active IE for fear of infecting newly implanted/repaired valves, but the need for this, in the present era of enhanced antimicrobial stewardship, has been questioned. In our institution, the choice and duration of antimicrobial therapy is tailored to individual patients by a multidisciplinary team with an interest in IE. The influence of the duration of postoperative antibiotic therapy on outcomes was studied in patients requiring surgery prior to the completion of a planned course of antibiotic therapy. METHODS: This was a retrospective observational study on patients with acute IE requiring surgery between January 2004 and December 2015. The primary outcome was relapse. Secondary outcomes were early reoperation and 1-year mortality. RESULTS: In total, 182 IE episodes were included in the final analysis. The median duration of postoperative antibiotic therapy was 23.5 days (interquartile range 12–40 days) and decreased significantly during the period of study (P

IntroductionPermanent artificial pacemaker implantation is a safe and effective treatment for bradycardia and is associated with extended longevity and improved quality of life. However, the most common long-term complication of standard pacemaker therapy is pacemaker-associated heart failure. Pacemaker follow-up is potentially an opportunity to screen for heart failure to assess and optimise patient devices and medical therapy.Methods and analysisThe study is a multicentre, phase-3 randomised trial. The 1200 participants will be people who have a permanent pacemaker for bradycardia for at least 12 months, randomly assigned to undergo a transthoracic echocardiogram with their pacemaker check, thereby tailoring their management directed by left ventricular function or the pacemaker check alone, continuing with routine follow-up. The primary outcome measure is time to all-cause mortality or heart failure hospitalisation. Secondary outcomes include external validation of our risk stratification model to predict onset of heart failure and quality of life assessment.Ethics and DisseminationThe trial design and protocol have received national ethical approval (12/YH/0487). The results of this randomised trial will be published in international peer-reviewed journals, communicated to healthcare professionals and patient involvement groups and highlighted using social media campaigns.Trial registration numberNCT01819662.

Introduction Prosthetic valve endocarditis (PVE) is a recognised and serious complication following surgical aortic valve replacement, with an incidence of 0.3–1.2% per year and an in-hospital mortality of >20%. The incidence and outcomes of PVE following transcatheter aortic valve implantation (TAVI) are less well established. Previously published studies suggest the incidence of PVE in the first year following TAVI is 0.5–3.1%, the rate of in-hospital mortality 11–47%, and mortality during two years follow-up of 67%. However, a number of questions remain unanswered, including the incidence of PVE per TAVI-year, the variation in incidence by year post-procedure and the diagnostic sensitivity of the modified Duke criteria. Methods This retrospective study of the incidence of TAVI-PVE has been designed and reported using the STROBE statement. We included all adults who underwent TAVI at Leeds Teaching Hospitals NHS Trust between 1st January 2008 and 31st December 2018. Cases of TAVI-PVE were identified from the Leeds Endocarditis Service database and all clinical, microbiological, echocardiographic and outcome data was retrieved from electronic patient records. Results During the 10-year study period 1337 patients underwent TAVI and the median follow-up was 2.3 years (interquartile range 1.3–4.0 years). In this time, 13 patients (0.97%) were diagnosed with TAVI-PVE; 1 presented within 30 days of TAVI (7.7%) and 5 presented in the first-year post-procedure (38.5%). The mean age of patients diagnosed with TAVI-PVE was 81.3 years (SD 5.1 years), and the mean time between TAVI and diagnosis with TAVI-PVE was 653 days (SD 541.9 days). Out of the 13 patients diagnosed with TAVI-PVE, only 4 (30.8%) fulfilled the modified Duke criteria for definite infective endocarditis (IE). The remaining 9 patients (69.2%) fulfilled the modified Duke criteria for possible IE. The most common reason for patients not fulfilling definite criteria was lack of echocardiographic features. In the majority of cases (7/13; 53.8%) the causative organism was found to be streptococcal. The cumulative incidence of TAVI-PVE has risen in line with the number of patients living with TAVI prostheses and the cumulative number of TAVI years (figure 1). However, when assessed in relation to the number of 100-TAVI years, the infection rate has fallen from a peak of 3.6 in 2009 and has remained relatively static (between 0.19–0.38) over the last 6 years (figure 2). Seven out of the 13 patients died within the study period giving an overall mortality rate of 53.8%. Five of those deaths occurred during the hospital admission, giving an in-hospital mortality rate of 38.5%, and these were all attributable TAVI-PVE or related complications. Conclusion The overall incidence of TAVI-PVE in our institution is 0.97%, with an associated mortality of 53.8%. The incidence relative to the number of TAVI-years has fallen and has remained static in recent years. Interestingly, the modified Duke criteria has a relatively low sensitivity in the diagnosis of TAVI-PVE, due to lack of diagnostic echocardiographic features. This may be a result of TAVI-PVE being less likely to demonstrate new paravalvular leak than SAVR-PVE due to the absence of suturing material in the former. As such, a high index of suspicion is required. Conflict of Interest None

Background Patients with chronic heart failure (HF) secondary to left ventricular systolic dysfunction (LVSD) are frequently deficient in vitamin D. Low vitamin D levels are associated with a worse prognosis.

Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below.Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images.Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers.Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential.

IntroductionElectrical coupling index (ECI) and contact force (CF) have been developed to aid lesion formation during catheter ablation. ECI measures tissue impedance and capacitance whilst CF measures direct contact. The aim was to determine whether the presence of catheter / tissue interaction information, such as ECI and CF, reduce time to achieve bidirectional cavotricuspid isthmus block during atrial flutter (AFL) ablation.MethodsPatients with paroxysmal or persistent AFL were randomised to CF visible (range 5-40g), CF not visible, ECI visible (change of 12%) or ECI not visible. Follow-up occurred at 3 and 6 months and included a 7 day ECG recording. The primary endpoint was time to bidirectional cavotricuspid isthmus block.Results114 patients were randomised, 16 were excluded. Time to bidirectional block was significantly shorter when ECI was visible (median 30.0 mins (IQR 31) to median 10.5mins (IQR 12) p 0.023) versus ECI not visible. There was a trend towards a shorter time to bidirectional block when CF was visible. Higher force was applied when CF was visible (median 9.03g (IQR 7.4) vs. 11.3g (5.5) p 0.017). There was no difference in the acute recurrence of conduction between groups. The complication rate was 2%, AFL recurrence was 1.1% and at 6 month follow-up, 12% had atrial fibrillation.ConclusionThe use of tissue contact information during AFL ablation was associated with reduced time taken to achieve bidirectional block when ECI was visible. Contact force data improved contact when visible with a trend towards a reduction in the procedural endpoint. ClinicalTrials.gov trial identifier: NCT02490033.

Background Intravenous drug use (IVDU) is a recognised predisposition for the development of infective endocarditis (IE). There is controversy regarding surgery for these patients because of relapse due to non-compliance with medical therapy and recurrence due to ongoing IVDU. This study aims to describe the outcomes in a large cohort of patients referred to a single tertiary centre. Methods Between 01/01/06 and 31/12/16 consecutive patients referred to the endocarditis multidisciplinary team were identified from our electronic database. Patients were included if they were either Duke’s confirmed or Duke’s possible and treated for IE and IVDU within 90 days. Affected valves and microorganisms were recorded, as well as indications for, type and number of operations. Outcomes were relapse (re-infection with same microorganism within 1 year), recurrence (infection with different organism, or same organism beyond 1 year), further surgical intervention and all-cause mortality. Results In total, there were 105 episodes in 92 patients; 92 episodes were Duke’s definite, and 13 Duke’s possible. The incidence of IE varied considerably year-on-year, but median age increased. Staphylococcus aureus (59) was the most frequently observed pathogen, followed by Streptococcus spp. (31), Enterococcus spp. (8), Staphylococcus. epidermidis (2), Candida spp. (2), Pseudomonas aeruginosa (1) and Corynebacterium diphtheriae (1). 7 episodes (6.67%) were culture negative. Ninety-one episodes affected native values and 10, prosthetic valves. More episodes affected left sided structures (78) than right (40) and the mitral valve was most commonly implicated (42), followed by tricuspid (38), aortic (36) and pulmonary (2). Pacemaker lead infection occurred in one patient. Forty-eight (45.7%) episodes required surgery; bioprosthetic valves for left sided disease were commonest with 17 aortic and 10 mitral valves compared to 6 and 8 mechanical valves respectively. Intervention for right sided disease was uncommon, with only 8 bioprosthetic tricuspid valves and one abandoned attempt at pulmonary valve surgery. Only one patient underwent further surgery following late recurrence with S. epidermidis affecting a bioprosthetic mitral valve. Three (3.26%) patients relapsed, 1 patient relapsed twice. 12 (13.0%) patients had recurrence, one patient had two recurrences. All-cause mortality was 4.35% at 30 days, 26.4% at 1 year and 36.4% at 3 years. Unadjusted mortality was higher in patients who underwent surgery, reflecting differences at baseline. Implications Contrary to common perception, IE in IVDU patients affected left sided structures more commonly than and right and surgery was commonly indicated. The rate of relapse was low, but the recurrence rate was high. All-cause mortality following an episode of IE is high, and so surgery remains controversial, especially in patients who continue IVDU.

Aims: Previous studies indicate that South Asians (SAs) may have a reduced risk of developing atrial fibrillation (AF) despite having a higher prevalence of traditional cardiovascular risk factors. This observational study was designed to explore the relative differences between SAs and Whites in a well-defined, multi-ethnic population with careful consideration of traditional cardiovascular risk factors that are thought to contribute to the development of AF. Methods and results: Anonymized data from 417 575 adults were sourced from primary care records within Bradford Metropolitan District, UK. Atrial fibrillation diagnosis was indicated by the presence on the AF Quality Outcomes Framework register. Self-reported ethnicity was mapped to census ethnic codes. The age-standardized prevalence rates of AF were calculated for comparison between the White and SA populations; our study sample presented relative proportions of 2.39 and 0.4%. Multivariable logistic regression analysis was performed to estimate the odds of developing AF given SA ethnicity. Adjustment for age, sex, and established risk factors found a 71% reduction in odds of AF in SAs when compared with Whites [odds ratio (OR): 0.29, 95% confidence interval (CI): 0.26–0.32]. When stratified by ethnicity, analyses revealed significantly different odds of AF for patients with diabetes; diabetes was not associated with the development of AF in the SA population (0.81, 95% CI: 0.63–1.05). Conclusion: This study, in a multi-ethnic population, presents ethnicity as a predictor of AF in which prevalence is significantly lower in SAs when compared with Whites. This is despite SAs having a higher frequency of established risk factors for the development of AF, such as ischaemic heart disease, heart failure, hypertension, and type 2 diabetes. These findings are consistent with previous literature and add weight to the need for further investigation, although this is the first study to investigate the differential associations of individual risk factors with development of AF.

Introduction: Virtual colonoscopy has proven to be a reliable, sensitive technique and is now widely adopted in routine clinical practice. We present a novel extension to virtual colonoscopy by incorporating the immersive Oculus Rift virtual reality technology. We describe our initial experience to explore its potential diagnostic benefit. To the best of our knowledge, this is the first Oculus Rift related publication in the radiology field. Method: A procedure for generating an Oculus Rift virtual colonoscopy (ORVC) has been created. It is derived from a CT image of an air/CO 2 inflated colon with contrast labelled faecal matter. The mucosal surface is segmented from its surroundings and subsequently meshed and rendered to produce a 3D surface. The mucosal surface is then imported into the Unity game engine along with the calculated coordinates of its centreline. Within Unity, a virtual reality camera is assigned to travel both outside and inside the colon, aided by controls allocated to an Xbox controller. Two ORVCs were created from differing quality CT data and trialled by two experienced radiologists and a gastroenterologist. Results: The ORVCs prompted an enthusiastic response from the clinicians. It was considered to offer potential for improved diagnostic power but further development is required if its full capability is to be realised. Conclusions: A mechanism for examining virtual colonoscopies within the immersive environment of the Oculus Rift has been developed. The resulting ORVCs were trialled by three clinicians with largely positive feedback providing encouragement for pursuing this work further.

Diabetes mellitus (DM) is an established adverse prognostic factor in patients sustaining myocardial infarction (MI). However, its impact on long-term survival remains less clear. The aim of this observational study was to quantify lifetime mortality and years of life lost after MI in patients with and without DM.In 1995, 2153 individuals with MI were recruited from 20 adjacent hospitals within Yorkshire, UK. Median survival, all-cause mortality at 20 years and lost years of life when compared to actuarial predictions were compared in patients with and without DM. Landmark analyses were conducted to define the ongoing impact of DM beyond specified time points.13% (279/2153) had known DM. They experienced higher mortality at 30 days (33.1% vs 24.6%; p0.0001) and at 20 years (84.9% vs 75.7%; p0.0001). Overall, there was a 48% increased risk of death (p0.0001), which persisted after adjustment for potential confounders. There was no interaction between DM and prior MI in predicting mortality (p=0.67). Median survival decreased by 3.3 years (p0.0001). The adverse impact of DM persisted in sequential landmark analyses at 1, 5 and 10 years. Presence of DM conferred 2 extra years of life lost when compared with actuarial predictions (8 vs 6 years; p0.0001).DM remains an independent adverse prognostic factor in the long-term after MI. Persistently diverging survival curves support enduring efforts to reduce mortality late after MI.

Objective: A non-invasive diagnostic technique for abdominal adhesions is not currently available. Capture of abdominal motion due to respiration in cine-MRI has shown promise, but is difficult to interpret. This article explores the value of a complimentary diagnostic aid to facilitate the non-invasive detection of abdominal adhesions using cine-MRI. Method: An image processing technique was developed to quantify the amount of sliding that occurs between the organs of the abdomen and the abdominal wall in sagittal cine-MRI slices. The technique produces a “sheargram” which depicts the amount of sliding which has occurred over 1–3 respiratory cycles. A retrospective cohort of 52 patients, scanned for suspected adhesions, made 281 cine-MRI sagittal slices available for processing. The resulting sheargrams were reported by two operators and compared with expert clinical judgment of the cine-MRI scans. Results: The sheargram matched clinical judgment in 84% of all sagittal slices and 93–96% of positive adhesions were identified on the sheargram. The sheargram displayed a slight skew towards sensitivity over specificity, with a high positive adhesion detection rate but at the expense of false positives. Conclusion: Good correlation between sheargram and absence/presence of inferred adhesions indicates quantification of sliding motion has potential to aid adhesion detection in cine-MRI. Advances in knowledge: This is the first attempt to clinically evaluate a novel image processing technique quantifying the sliding motion of the abdominal contents against the abdominal wall. The results of this pilot study reveal its potential as a diagnostic aid for detection of abdominal adhesions.

This paper reports novel development and preliminary application of an image registration technique for diagnosis of abdominal adhesions imaged with cine-MRI (cMRI). Adhesions can severely compromise the movement and physiological function of the abdominal contents, and their presence is difficult to detect. The image registration approach presented here is designed to expose anomalies in movement of the abdominal organs, providing a movement signature that is indicative of underlying structural abnormalities. Validation of the technique was performed using structurally based in vitro and in silico models, supported with Receiver Operating Characteristic (ROC) methods. For the more challenging cases presented to the small cohort of 4 observers, the AUC (area under curve) improved from a mean value of 0.67 ± 0.02 (without image registration assistance) to a value of 0.87 ± 0.02 when image registration support was included. Also, in these cases, a reduction in time to diagnosis was observed, decreasing by between 20% and 50%. These results provided sufficient confidence to apply the image registration diagnostic protocol to sample magnetic resonance imaging data from healthy volunteers as well as a patient suffering from encapsulating peritoneal sclerosis (an extreme form of adhesions) where immobilization of the gut by cocooning of the small bowel is observed. The results as a whole support the hypothesis that movement analysis using image registration offers a possible method for detecting underlying structural anomalies and encourages further investigation.

After a meal the activity of the gut increases markedly as digestion takes place. Associated with this increase in activity is an increase in blood flow, which has been shown to be dependent on factors such as caloric content and constitution of the meal. Much qualitative work has been carried out regarding mechanisms for the presence of food in a section of gut producing increased blood flow to that section, but there are still many aspects of this process that are not fully understood. In this paper we briefly review current knowledge on several relevant areas relating to gut blood flow, focusing on quantitative data where available and highlighting areas where further research is needed. We then present new data on the effect of feeding on flow in the superior mesenteric artery. Finally, we describe a framework for combining this data to produce a single model describing the mechanisms involved in postprandial hyperaemia. For a section of the model, where appropriate data are available, preliminary results are presented.

Introduction Patients with cardiovascular disease are living longer and are more frequently accessing healthcare resources. The Evaluation of the Methods and Management of Acute Coronary Events (EMMACE)-3 national study is designed to improve understanding of the effect of quality of care on health-related outcomes for patients hospitalised with acute coronary syndrome (ACS). Methods and analysis EMMACE-3 is a longitudinal study of 5556 patients hospitalised with an ACS in England. The study collects repeated measures of health-related quality of life, information about medications and patient adherence profiles, a survey of hospital facilities, and morbidity and mortality data from linkages to multiple electronic health records. Together with EMMACE-3X and EMMACE-4, EMMACE-3 will assimilate detailed information for about 13 000 patients across more than 60 hospitals in England. Ethics and dissemination EMMACE-3 was given a favourable ethical opinion by Leeds (West) Research Ethics committee (REC reference: 10/H131374). On successful application, study data will be shared with academic collaborators. The findings from EMMACE-3 will be disseminated through peer-reviewed publications, at scientific conferences, the media, and through patient and public involvement. Study registration number ClinicalTrials.gov Identifier: NCT01808027. Information about the study is also available at EMMACE.org.

Introduction Peritoneal adhesion formation is a common complication of abdominal surgery and is associated with chronic abdominal pain, bowel obstruction, female infertility and reoperation complications. Non-invasive diagnosis has the potential to improve patient management by determining the cause of symptoms. Cine-MR (cMR) has been used for this purpose1but in our experience has proven labour intensive and with high inter-operator variability. We previously presented a mathematical interpretation of abdominal movement in cMR to infer gross abnormalities.2We have since refined our approach to detect more subtle changes. Here we present the preliminary results of our new technique. Method Sagittal cMR images were obtained using a previously defined scanning protocol.2Images from 3 patients were analysed, 2 with abdominal wall adhesions and 1 without. The principle driving the methodology is the expectation that an adhesion’s resistance to visceral slide produces a quantifiable reduction in shear at that location. The method entails image processing of cMR images in which visceral slide is captured over several breathing cycles. Specifically this involves: 1. Defining a line of demarcation between the sliding regions, typically the abdominal contents and the abdominal wall. 2. Independent interrogation of the respective modes of motion in these separate regions using image registration software. 3. Deduction of the relative motion at the boundary between the two regions 4. Extraction of the magnitude of shear and its presentation in a ‘sheargram’. Results The images display the accumulated shear over approximately 3 respiratory cycles in patients with and without abdominal wall adhesions. The left image (with adhesions) shows a marked reduction in shear in the lower fifth of the abdominal wall correlating to a surgically verified adhesion. The reliability of these preliminary results is also supported by the more even distribution of shear observed in a patient without anterior abdominal wall adhesions (right image). Conclusion Our pilot results demonstrate the potential of this newly developed image analysis technique. In combination with other relevant diagnostic information it facilitates the efficient localisation of adhesions to the abdominal wall. A larger study is in progress to confirm these results. Disclosure of interest None Declared. ![Abstract PTH-243 Figure 1][1] Abstract PTH-243 Figure 1 References 1. Lienemann, et al . Radiology 2000; 217 (2):421–5 2. Fenner, et al . Phys Medica 2014; 30 (4):437–447 [1]: pending:yes

In contrast to its prevalence in the surrounding vasculature, occurrence of primary atherosclerotic disease in the superior mesenteric artery (SMA) is rare (Glagov et al., 1988. Hemodynamics and atherosclerosis, Insights and perspectives gained from studies of human arteries. Archives of Pathology and Laboratory Medicine 112(10), 1018-1031; Hansen et al., 2004. Mesenteric artery disease in the elderly. Journal of Vascular Surgery 40(1), 45-52). We hypothesise that this sparing might be attributed to more favourable haemodynamic characteristics in the SMA than in other vessels locally. Dynamic magnetic resonance imaging (MRI) images established that the SMA is highly mobile (Jeays, 2006. Investigation of blood flow in the superior mesenteric artery and its potential influence on atheroma and gut ischaemia. Ph.D. Thesis, University of Sheffield), and thus that an analysis based on rigid geometry might be inappropriate. This paper describes an efficient methodology for the construction of a patient-specific, time-dependent model of an arterial segment and reports the results of a haemodynamic characterisation of the SMA for one individual. A transient computational fluid dynamic (CFD) model was constructed by morphing a parametric mesh constructed from simple geometric primitives. This process has the merit that it is easy to control the element size distribution mapped onto the original geometric primitives. It is robust in operation, and is ideally suited to the generation of dynamic CFD meshes of arterial systems that are free from major pathology. Flow boundary conditions were determined based on phase contrast MRI velocity measurements. Comparative studies with rigid walls and with moving walls, based on the transient data, indicated that, despite the significant motion of the SMA (radial dilation of the order of 10% and translation of the order of the radius), the maximum (spatially and temporally-resolved) wall shear stresses changed by no more than 21.6% of a global norm, and the average change was less than 2.1%.

Aim Atherothrombotic disease is endemic throughout the world. In the UK a new system for supporting clinical research was introduced in 2007 with the creation of the National Institute of Health Research (NIHR) which acts as the research arm of the National Health Service (NHS). In the current study our primary objective was to assess the impact of this important government initiative on patient involvement in research. Methods All clinical studies that wish to have support from the NIHR funding stream have first to be adopted onto a central research portfolio. This process is ‘automatic’ for studies with specific recognised grant support, and is otherwise based upon an assessment by an expert panel. Information regarding study design and recruitment are collected at the time of adoption and then at monthly intervals. Studies are allocated to an NIHR Clinical Research Network and to the relevant ‘Specialty’ which includes ‘Cardiovascular’ and within that to a subspecialty portfolio—in this case ‘Atherothrombosis’. It is further noted if a study is (i) multicentre or single centre (ii) national or international (iii) observational or interventional. Results The change in monthly recruitment between April 2008 and August 2012 is charted relative to study infrastructure (Panel A) and design (Panel B). Monthly recruitment rates have grown significantly to a maximum of 818 patients per month. Conclusions Since the NIHR was set up along with the development of a NIHR Comprehensive Clinical Research Network (CCRN) which includes support for cardiovascular research within its remit, the number of patients involved in studies of atherothrombosis has increased substantially. The recruitment rate is currently around 800 patients per month, representing an increase of eightfold since April 2010. The coordination of research into atherothrombosis through a national networked approach, along with effective local mechanisms for delivering support and a system for directing funding based on previous recruitment performance has had a significant effect on the UK9s capacity to undertake research into atherothrombosis.

Introduction Peritoneal dialysis (PD) is the preferred method for long-term management of patients with end-stage renal failure. Over time, peritoneal fibrosis leads to dysfunction and in some to encapsulating peritoneal sclerosis (EPS). This is characterised by a diffuse visceral film forming a tightening cocoon, which ultimately ‘strangles’ its contents. The patients present with bowel obstruction leading to eventual small intestinal failure, ischaemia and infarction. Surgery can be curative. There is no reliable method for early detection. Recent novel developments based on an MR image analysis method have permitted detection of adhesions from Crohn9s disease and surgery, which typically are focal or multifocal. EPS, being adhesions forming a ‘cocoon’, is also likely to disrupt movement but with a different pattern. We hypothesised it may be detectable with our system. This pilot is a proof-of-principle investigation. MR video-loop of abdominal examination in health shows remarkably smooth movement. Traditional MRI concentrates on structure; by focusing on movement instead we noticed disruption due to Crohn9s and surgical adhesions. Methods The Sheffield Image Registration Toolkit was used to develop software for more rapid review. Images are acquired at different stages in the respiratory cycle; registration links each point in an image to its corresponding point in another. Data are displayed as vectors and contours. In an earlier study standard dynamic non-contrast MR images were obtained from healthy volunteers; the movement pattern could be classified as ‘smooth’ (normal) or ‘disrupted’ (perhaps indicating adhesions). Three patients switched from PD to haemodialysis awaiting surgery with suspected EPS were also investigated. Results Surgical findings confirmed EPS. 18 volunteers were studied; representative processed sagittal images from 2 volunteers and 2 patients are shown. There is a striking difference in movement pattern. In health movement is marked in the upper abdomen but still very noticeable in the lower part. In EPS movement is restricted to the upper abdomen. This is shown by the distribution of the red contours which signify maximum movement (and blue the least). Conclusion This pilot study suggests dynamic cine-MRI coupled with advanced image analysis of movement can detect disruption due to an EPS cocoon. The method offers an approach in PD patients for early detection of disordered abdominal movement, signifying potential dialysis failure.