Comprehensive plasma metabolomic and lipidomic analyses reveal potential biomarkers for heart failure

MetaboAnalyst (www.metaboanalyst.ca) is a web server designed to permit comprehensive metabolomic data analysis, visualization and interpretation. It supports a wide range of complex statistical calculations and high quality graphical rendering functions that require significant computational resources. First introduced in 2009, MetaboAnalyst has experienced more than a 50X growth in user traffic (>50 000 jobs processed each month). In order to keep up with the rapidly increasing computational demands and a growing number of requests to support translational and systems biology applications, we performed a substantial rewrite and major feature upgrade of the server. The result is MetaboAnalyst 3.0. By completely re-implementing the MetaboAnalyst suite using the latest web framework technologies, we have been able substantially improve its performance, capacity and user interactivity. Three new modules have also been added including: (i) a module for biomarker analysis based on the calculation of receiver operating characteristic curves; (ii) a module for sample size estimation and power analysis for improved planning of metabolomics studies and (iii) a module to support integrative pathway analysis for both genes and metabolites. In addition, popular features found in existing modules have been significantly enhanced by upgrading the graphical output, expanding the compound libraries and by adding support for more diverse organisms.

Half of patients with chronic heart failure (CHF) have preserved left-ventricular ejection fraction (LVEF), but few treatments have specifically been assessed in such patients. In previous studies of patients with CHF and low LVEF or vascular disease and preserved LVEF, inhibition of the renin-angiotensin system is beneficial. We investigated the effect of addition of an angiotensin-receptor blocker to current treatments. Between March, 1999, and July, 2000, we randomly assigned 3023 patients candesartan (n=1514, target dose 32 mg once daily) or matching placebo (n=1509). Patients had New York Heart Association functional class II-IV CHF and LVEF higher than 40%. The primary outcome was cardiovascular death or admission to hospital for CHF. Analysis was done by intention to treat. Median follow-up was 36.6 months. 333 (22%) patients in the candesartan and 366 (24%) in the placebo group experienced the primary outcome (unadjusted hazard ratio 0.89 [95% CI 0.77-1.03], p=0.118; covariate adjusted 0.86 [0.74-1.0], p=0.051). Cardiovascular death did not differ between groups (170 vs 170), but fewer patients in the candesartan group than in the placebo group were admitted to hospital for CHF once (230 vs 279, p=0.017) or multiple times. Composite outcomes that included non-fatal myocardial infarction and non-fatal stroke showed similar results to the primary composite (388 vs 429; unadjusted 0.88 [0.77-1.01], p=0.078; covariate adjusted 0.86 [0.75-0.99], p=0.037). Candesartan has a moderate impact in preventing admissions for CHF among patients who have heart failure and LVEF higher than 40%.