Influence of preoperative serum N-terminal pro-brain type natriuretic peptide on the postoperative outcome and survival rates of coronary artery bypass patients

BACKGROUND: The N-terminal fragment of pro-brain type natriuretic peptide (NT-proBNP) is an established biomarker for cardiac failure. OBJECTIVE: To determine the influence of preoperative serum NT-proBNP on postoperative outcome and mid-term survival in patients undergoing coronary artery bypass grafting (CABG). METHODS: In 819 patients undergoing isolated CABG surgery preoperative serum NT-proBNP levels were measured. NT-proBNP was correlated with various postoperative outcome parameters and survival rate after a median follow-up time of 18 (0.5-44) months. Risk factors of mortality were identified using &#967;2, Mann-Whitney test, and Cox regression. RESULTS: NT-proBNP levels >430 ng/ml and >502 ng/ml predicted hospital and overall mortality (p<0.05), with an incidence of 1.6% and 4%, respectively. Kaplan-Meier analysis revealed decreased survival rates in patients with NT-proBNP >502 ng/ml (p=0.001). Age, preoperative serum creatinine, diabetes, chronic obstructive pulmonary disease, low left ventricular ejection fraction and BNP levels >502 ng/ml were isolated as risk factors for overall mortality. Multivariate Cox regression analysis, including the known factors influencing NT-proBNP levels, identified NT-proBNP as an independent risk factor for mortality (OR = 3.079 (CI = 1.149-8.247), p = 0.025). Preoperative NT-proBNP levels >502 ng/ml were associated with increased ventilation time (p=0.005), longer intensive care unit stay (p=0.001), higher incidence of postoperative hemofiltration (p=0.001), use of intra-aortic balloon pump (p<0.001), and postoperative atrial fibrillation (p=0.031) CONCLUSION: Preoperative NT-proBNP levels >502 ng/ml predict mid-term mortality after isolated CABG and are associated with significantly higher hospital mortality and perioperative complications

Identifying patients at risk: multi-centre comparison of HeartMate 3 and HeartWare left ventricular assist devices

Aims: Since the withdrawal of HeartWare (HVAD) from the global market, there is an ongoing discussion if and which patients require prophylactically exchange for a HeartMate 3 (HM3). Therefore, it is important to study outcome differences between HVAD and HM3 patients. Because centres differ in patient selection and standard of care, we performed a propensity score (PS)-based study including centres that implanted both devices and aimed to identify which HVAD patients are at highest risk. Methods and results: We performed an international multi-centre study (n = 1021) including centres that implanted HVAD and HM3. PS-matching was performed using clinical variables and the implanting centre. Survival and complications were compared. As a sensitivity analysis, PS-adjusted Cox regression was performed. Landmark analysis with conditional survival >2 years was conducted to evaluate long-term survival differences. To identify which HVAD patients may benefit from a HM3 upgrade, Cox regression using pre-operative variables and their interaction with device type was performed. Survival was significantly better for HM3 patients (P 2 years after implantation (P = 0.03). None of the pre-operative variable interactions in the Cox regression were significant. Conclusions: HM3 patients have a significantly better survival and a lower incidence of ischaemic strokes and pump thrombosis than HVAD patients. This survival difference persisted after 2 years of implantation. Additional research using post-operative variables is warranted to identify which HVAD patients need an upgrade to HM3 or expedited transplantation

Loop-Mediated Isothermal Amplification for Laboratory Confirmation of Buruli Ulcer Disease-Towards a Point-of-Care Test

Background As the major burden of Buruli ulcer disease (BUD) occurs in remote rural areas, development of point-of-care (POC) tests is considered a research priority to bring diagnostic services closer to the patients. Loop-mediated isothermal amplification (LAMP),a simple, robust and cost-effective technology, has been selected as a promising POC test candidate. Three BUD-specific LAMP assays are available to date, but various technical challenges still hamper decentralized application. To overcome the requirement of cold-chains for transport and storage of reagents, the aim of this study was to establish a dry-reagent-based LAMP assay (DRB-LAMP) employing lyophilized reagents. Methodology/Principal Findings Following the design of an IS2404 based conventional LAMP (cLAMP) assay suitable to apply lyophilized reagents, a lyophylization protocol for the DRB-LAMP format was developed. Clinical performance of cLAMP was validated through testing of 140 clinical samples from 91 suspected BUD cases by routine assays, i.e. IS2404 dry-reagent-based (DRB) PCR, conventional IS2404 PCR (cPCR),IS2404 qPCR, compared to cLAMP. Whereas qPCR rendered an additional 10% of confirmed cases and samples respectively, case confirmation and positivity rates of DRB-PCR or cPCR (64.84% and 56.43%;100% concordant results in both assays) and cLAMP (62.64% and 52.86%) were comparable and there was no significant difference between the sensitivity of the assays (DRB PCR and cPCR, 86.76%;cLAMP, 83.82%). Likewise, sensitivity of cLAMP (95.83%) and DRB-LAMP (91.67%) were comparable as determined on a set of 24 samples tested positive in all routine assays. Conclusions/Significance Both LAMP formats constitute equivalent alternatives to conventional PCR techniques. Provided the envisaged availability of field friendly DNA extraction formats, both assays are suitable for decentralized laboratory confirmation of BUD, whereby DRB-LAMP scores with the additional advantage of not requiring cold-chains. As validation of the assays was conducted in a third-level laboratory environment, field based evaluation trials are necessary to determine the clinical performance at peripheral health care level

Impact of Right Ventricular Performance in Patients Undergoing Extracorporeal Membrane Oxygenation Following Cardiac Surgery

Background: Extracorporeal membrane oxygenation following cardiac surgery safeguards end‐organ oxygenation but unfavorably alters cardiac hemodynamics. Along with the detrimental effects of cardiac surgery to the right heart, this might impact outcome, particularly in patients with preexisting right ventricular (RV) dysfunction. We sought to determine the prognostic impact of RV function and to improve established risk‐prediction models in this vulnerable patient cohort. Methods and Results: Of 240 patients undergoing extracorporeal membrane oxygenation support following cardiac surgery, 111 had echocardiographic examinations at our institution before implantation of extracorporeal membrane oxygenation and were thus included. Median age was 67 years (interquartile range 60‐74), and 74 patients were male. During a median follow‐up of 27 months (interquartile range 16‐63), 75 patients died. Fifty‐one patients died within 30 days, 75 during long‐term follow‐up (median follow‐up 27 months, minimum 5 months, maximum 125 months). Metrics of RV function were the strongest predictors of outcome, even stronger than left ventricular function (P<0.001 for receiver operating characteristics comparisons). Specifically, RV free‐wall strain was a powerful predictor univariately and after adjustment for clinical variables, Simplified Acute Physiology Score‐3, tricuspid regurgitation, surgery type and duration with adjusted hazard ratios of 0.41 (95%CI 0.24‐0.68; P=0.001) for 30‐day mortality and 0.48 (95%CI 0.33‐0.71; P<0.001) for long‐term mortality for a 1‐SD (SD=−6%) change in RV free‐wall strain. Combined assessment of the additive EuroSCORE and RV free‐wall strain improved risk classification by a net reclassification improvement of 57% for 30‐day mortality (P=0.01) and 56% for long‐term mortality (P=0.02) compared with the additive EuroSCORE alone. Conclusions: RV function is strongly linked to mortality, even after adjustment for baseline variables and clinical risk scores. RV performance improves established risk prediction models for short‐ and long‐term mortality