Big data analytics in cardiovascular sciences

Introduction It has been challenging for researchers to access granular electronic health record (EHR) data at scale in England. The National Institute for Health Research (NIHR) Health Informatics Collaborative (HIC) enables the sharing of routine EHR data across NHS hospitals for research. One emerging prospect is to use big data to traverse the translational spectrum. As an example of an early discovery phase study, I assessed the effect of invasive versus non-invasive management on the survival of patients aged 80 years or older with non-ST elevation myocardial infarction (NSTEMI) (SENIOR-NSTEMI Study). As an example of a later implementation phase study, I determined the relationship between the full spectrum of troponin level and mortality in patients in whom troponin testing was performed for clinical purposes (TROP-RISK Study). Methods Five NHS Trusts contributed data: Imperial, University College London, Oxford, King’s and Guy’s and St Thomas’. Microsoft SQL was used to develop a dataset of 257,948 consecutive patients who had a troponin measured between 2010 and 2017. Phenotypically detailed data were extracted, including patient demographics, blood tests, procedural data, and survival status. All studies conducted were retrospective cohort studies. For the SENIOR-NSTEMI Study, eligible patients were 80 years or older who were diagnosed with NSTEMI. Mortality hazard ratios were estimated comparing invasive with non-invasive management. For the TROP-RISK Study, the relation between peak troponin level and all-cause mortality was modelled using multivariable adjusted restricted cubic spline Cox regression analyses. Results For the SENIOR-NSTEMI Study, 2672 patients with NSTEMI were included who had a median age of 85 (interquartile range (IQR) 82-89) years of whom 59.8% received non-invasive management. During a median follow-up of 2.7 (IQR 1.0-4.5) years, the adjusted cumulative five-year mortality was 40% in the invasive and 63% in the non-invasive group (hazard ratio 0.52, 95% confidence interval 0.43-0.62). For the TROP-RISK Study, during a median follow-up of 1198 days (IQR 514-1866 days), 55,850 (21.7%) deaths occurred. There was an unexpected inverted U-shaped relation between troponin level and mortality in acute coronary syndrome (ACS) patients (n=120,049). The paradoxical decline in mortality at very high troponin levels may be driven in part by the changing case mix as troponin levels increase; a higher proportion of patients with very high troponin levels received invasive management. Conclusion Routinely collected EHR data can be aggregated across multiple sites to create highly granular datasets for research which can be used to answer research questions that cross the translational spectrum. The SENIOR-NSTEMI Study demonstrates a survival advantage of invasive compared with non-invasive management of NSTEMI patients aged 80 years or older, who were underrepresented in previous trials. In the TROP-RISK Study, the inverted U-shaped relationship between troponin level and mortality in ACS patients demonstrates that assembling sufficiently large datasets can cast light on patterns of disease that are impossible to adequately define in single centre studies.Open Acces

Factors associated with safe early discharge after transcatheter aortic valve implantation

  Background: As transcatheter aortic valve implantation (TAVI) becomes more straightforward, a larger proportion of patients will be well enough to be discharged early. This study sought to charac­terise the clinical features that allowed patients to be discharged early after TAVI and to evaluate the safety of an early discharge policy. Methods: All patients undergoing TAVI at the above cited center from August 2007 to March 2015 were included in this study. Baseline characteristics, in-hospital outcomes, re-admissions and mortality were compared. Results: Three hundred thirty-seven TAVIs were performed during the study period, and 18 died in-hospital (18/337, 5.3%). Of the remaining patients, 56 were discharged within 3 days of the index procedure (‘early discharge group’ 56/319, 17.5%). There was no difference between the early discharge and late discharge group in terms of Valve Academic Research Consortium-2 (VARC-2) criteria out­comes, all-cause re-admission rates and the need for permanent pacemaker implantation. Mortality at 1 year was better among the early discharge group (3.6% vs. 15.6%, p = 0.014); a reflection of baseline clinical differences. Conclusion: Early discharge of clinically selected TAVI patients is safe and appropriate. Lower logistic EuroSCORE, smaller delta creatinine and not developing any complications are factors associated with early discharge. (Cardiol J 2018; 25, 1: 14–23

Vascular endothelial growth factor-A165b is protective and restores endothelial glycocalyx in diabetic nephropathy

Diabetic nephropathy is the leading cause of ESRD in high-income countries and a growing problem across the world. Vascular endothelial growth factor-A (VEGF-A) is thought to be a critical mediator of vascular dysfunction in diabetic nephropathy, yet VEGF-A knockout and overexpression of angiogenic VEGF-A isoforms each worsen diabetic nephropathy. We examined the vasculoprotective effects of the VEGF-A isoform VEGF-A165b in diabetic nephropathy. Renal expression of VEGF-A165b mRNA was upregulated in diabetic individuals with well preserved kidney function, but not in those with progressive disease. Reproducing this VEGF-A165b upregulation in mouse podocytes in vivo prevented functional and histologic abnormalities in diabetic nephropathy. Biweekly systemic injections of recombinant human VEGF-A165b reduced features of diabetic nephropathy when initiated during early or advanced nephropathy in a model of type 1 diabetes and when initiated during early nephropathy in a model of type 2 diabetes. VEGF-A165b normalized glomerular permeability through phosphorylation of VEGF receptor 2 in glomerular endothelial cells, and reversed diabetes-induced damage to the glomerular endothelial glycocalyx. VEGF-A165b also improved the permeability function of isolated diabetic human glomeruli. These results show that VEGF-A165b acts via the endothelium to protect blood vessels and ameliorate diabetic nephropathy

Obstetric Emergencies.

Human gestation and birthing result in many deviations from usual physiology that are nonetheless normal to be seen. However, on occasion, certain complications in the obstetric patient can be life-threatening to both mother and fetus. Timely recognition of these disorders and allocation of the appropriate resources are especially important. These conditions often require an intensive care unit admission for closer monitoring and supportive care. They can affect an array of physiological systems and can lead to significant morbidity. Such complications are discussed in greater detail in this article

Interferometry based security hologram readable with an encoded key hologram

816-819A simple and cost-effective method for making security holograms has been presented, which incorporates holographic interferometry as verification feature in addition to spatially separated sharp focus spots. When the security hologram is illuminated with decoding reconstructing beam generated from an encoded key hologram, two spatially separated sharp focus spots emerge at the predefined positions and can be read through a photoelectric detector array. In addition, these focused spots upon divergence in longitudinal direction further generate specific kind of interferometric fringe patterns of random profile contained in them, which are suitable for further visual inspection. These machine-readable and visual verifiable features can be used for better counterfeit-resistant security codes in embossed holograms. Recording schemes for the formation of such security holograms and typical experimental results have been presented