PurposeTo assess the suitability of retinal images held in the UK Biobank - the largest retinal data repository in a prospective population-based cohort - for computer assisted vascular morphometry, generating measures that are commonly investigated as candidate biomarkers of systemic disease.MethodsNon-mydriatic fundus images from both eyes of 2,690 participants - people with a self-reported history of myocardial infarction (n=1,345) and a matched control group (n=1,345) - were analysed using VAMPIRE software. These images were drawn from those of 68,554 UK Biobank participants who underwent retinal imaging at recruitment. Four operators were trained in the use of the software to measure retinal vascular tortuosity and bifurcation geometry.ResultsTotal operator time was approximately 360 hours (4 minutes per image). 2,252 (84%) of participants had at least one image of sufficient quality for the software to process, i.e. there was sufficient detection of retinal vessels in the image by the software to attempt the measurement of the target parameters. 1,604 (60%) of participants had an image of at least one eye that was adequately analysed by the software, i.e. the measurement protocol was successfully completed. Increasing age was associated with a reduced proportion of images that could be processed (p=0.0004) and analysed (p<0.0001). Cases exhibited more acute arteriolar branching angles (p=0.02) as well as lower arteriolar and venular tortuosity (p<0.0001).ConclusionsA proportion of the retinal images in UK Biobank are of insufficient quality for automated analysis. However, the large size of the UK Biobank means that tens of thousands of images are available and suitable for computational analysis. Parametric information measured from the retinas of participants with suspected cardiovascular disease was significantly different to that measured from a matched control group.

BackgroundMyocardial inflammation and injury occur during coronary artery bypass graft (CABG) surgery. We aimed to characterise these processes during routine CABG surgery to inform the diagnosis of type 5 myocardial infarction.MethodsWe assessed 87 patients with stable coronary artery disease who underwent elective CABG surgery. Myocardial inflammation, injury and infarction were assessed using plasma inflammatory biomarkers, high-sensitivity cardiac troponin I (hs-cTnI) and cardiac magnetic resonance imaging (CMR) using both late gadolinium enhancement (LGE) and ultrasmall superparamagnetic particles of iron oxide (USPIO).ResultsSystemic humoral inflammatory biomarkers (myeloperoxidase, interleukin-6, interleukin-8 and c-reactive protein) increased in the post-operative period with C-reactive protein concentrations plateauing by 48 h (median area under the curve (AUC) 7530 [interquartile range (IQR) 6088 to 9027] mg/L/48 h). USPIO-defined cellular myocardial inflammation ranged from normal to those associated with type 1 myocardial infarction (median 80.2 [IQR 67.4 to 104.8] /s). Plasma hs-cTnI concentrations rose by ≥50-fold from baseline and exceeded 10-fold the upper limit of normal in all patients. Two distinct patterns of peak cTnI release were observed at 6 and 24 h. After CABG surgery, new LGE was seen in 20% (n = 18) of patients although clinical peri-operative type 5 myocardial infarction was diagnosed in only 9% (n = 8). LGE was associated with the delayed 24-h peak in hs-cTnI and its magnitude correlated with AUC plasma hs-cTnI concentrations (r = 0.33, p < 0.01) but not systemic inflammation, myocardial inflammation or bypass time.ConclusionPatients undergoing CABG surgery invariably have plasma hs-cTnI concentrations >10-fold the 99th centile upper limit of normal that is not attributable to inflammatory or ischemic injury alone. Peri-operative type 5 myocardial infarction is often unrecognised and is associated with a delayed 24-h peak in plasma hs-cTnI concentrations.Electronic supplementary materialThe online version of this article (doi: 10.1186/s13019-017-0681-6) contains supplementary material, which is available to authorized users.

Background: Using meta-regression, this article aims at establishing the minimum change in BMI-standard deviation score (SDS) needed to improve lipid profiles and blood pressure in children and adolescents with obesity, to aid future trials and guidelines. Methods: Studies with participants involved in lifestyle interventions, aged 4-19 years, with a diagnosis of obesity according to defined BMI thresholds, were considered for inclusion in a large systematic review. Interventions had to report pre-and postintervention (or mean change in) BMI-SDS, plus either systolic blood pressure (SBP), high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, and/or triglycerides (TGs). Random-effects meta-regression quantified the relationship between mean change in BMI-SDS and mean change in cardiovascular outcomes. Results: Seventy-one papers reported various cardiovascular measurements and mean change in BMI-SDS. Fifty-four, 59, 46, and 54 studies were analyzed, reporting a change in SBP, HDL, LDL, and TG, respectively. Reduction in mean BMI-SDS was significantly related to improvements in SBP, LDL, TG, and HDL (p < 0.05); BMI-SDS reductions of 1, 1.2, and 0.7 ensured a mean reduction of SBP, LDL, and TG, respectively, although an equivalent value for HDL improvement was indeterminate. Conclusion: Reductions in mean BMI-SDS of >1, >1.2, or >0.7 are likely to reduce SBP, LDL, and TG, respectively. Further studies are needed to clarify the optimal duration, intensity, and setting for interventions. Consistency is required regarding derived BMI values to facilitate future systematic reviews and meta-analyses.

Background Documentation of pregnancy status (PS) is an integral component of the assessment of women of reproductive age when admitted to hospital. Our aim was to determine how accurately PS was documented in a multicentre audit of female admissions to general surgery. Methods A prospective multicentre audit of elective and emergency admissions was performed in 18 Scottish centres between 08:00 on 11 May 2015 and 07:59 on 25 May 2015. The lower age limit was the minimum age for admission to the adult surgical ward and the upper age limit was 55 years. Results There were 2743 admissions, with 612 (22.3%) women of reproductive age. After 82 exclusions, the final total was 530: 169 (31.9%) elective and 361 (68.1%) emergency. Documentation of PS was achieved in 274 (51.7%) cases: 52 (30.8%) elective and 222 (61.5%) emergency. In 318 (88.1%) of the emergency admissions, the patient had abdominal pain. Of these, 211 (65.1%) had a documented PS. The possibility of pregnancy was established in 237 (44.7%) cases. Discussion Establishing the possibility of pregnancy before surgery is poor, particularly in the elective setting. Objective documentation of PS in the emergency setting in those with abdominal pain is also poor. Our study highlights an important safety issue in the management of female patients. We advocate electronic storage of pregnancy test results and new guidelines to cover both elective and emergency surgery. PS should form part of the pre-theatre safety brief and checklist.