The Prognostic Potential of Atrial Natriuretic Peptide on the Development of Postoperative Atrial Fibrillation after Cardiac Surgery.

BACKGROUND: Postoperative atrial fibrillation (POAF) represents a common complication after cardiac surgery associated with major adverse events and poor patient outcome. Tools for risk stratification of this arrhythmia remain scarce. Atrial natriuretic peptide (ANP) represents an easily assessable biomarker picturing atrial function and strain; however, its prognostic potential on the development of POAF has not been investigated so far. METHODS: Within the present investigation, 314 patients undergoing elective cardiac surgery were prospectively enrolled. Preoperative mid-region proANP (MR-proANP) values were assessed before the surgical intervention. Patients were followed prospectively and continuously screened for the development of arrhythmic events. RESULTS: A total of 138 individuals (43.9%) developed POAF. Median concentrations of MR-proANP were significantly higher within the POAF group (p < 0.001). MR-proANP showed a strong association with the development of POAF with a crude odds ratio (OR) of 1.68 per 1 standard deviation (1-SD; 95% confidence interval [CI]: 1.31-2.15; p < 0.001), which remained stable after comprehensive adjustment for confounders with an adjusted OR of 1.74 per 1-SD (95% CI: 1.17-2.58; p = 0.006). The discriminatory power of MR-proANP for the development of POAF was validated by the category-free net reclassification improvement (0.23 [95% CI: 0.0349-0.4193]; p = 0.022) and integrated discrimination increment (0.02 [95% CI: 0.0046-0.0397], p = 0.013). CONCLUSION: MR-proANP proved to be a strong and independent predictor of the development of POAF. Considering a personalized diagnostic and prognostic preoperative work-up, a standardized preoperative evaluation of MR-proANP levels might help to identify patients at risk for development of POAF after cardiac surgery.

Blood urea nitrogen has additive value beyond estimated glomerular filtration rate for prediction of long-term mortality in patients with acute myocardial infarction.

OBJECTIVES: Blood urea nitrogen (BUN) has been shown to independently predict short- and intermediate-term outcomes in patients with acute myocardial infarction (AMI). We aimed to assess the additive predictive value of BUN beyond estimated glomerular filtration rate (eGFR) in AMI patients with an 8.6-year follow-up. METHODS: This retrospective, observational single-centre study included 1332 consecutive AMI patients (median age 64 years, 58.4% male). BUN, creatinine and eGFR were determined at hospital admission. RESULTS: During a median follow-up of 8.6 years (interquartile range [IQR] 4.0-11.6), 408 patients (30.6%) experienced the study endpoint of cardiovascular mortality. BUN (median 17.0 mg/dL [IQR 13.5-22.7]) was a significant predictor of cardiovascular mortality in univariate Cox regression (hazard ratio (HR) per 1 standard deviation increase 2.10, 95% confidence interval [CI] 1.94-2.28, p < .001). This association remained significant after multivariable adjustment for demographics, clinical variables and eGFR (adjusted HR 1.52 [CI 1.16-2.00, p = .003]). The association between BUN and outcome was more pronounced in patients with eGFR >60 mL/min/1.73m2 (HR 2.81 [CI 2.20-3.58, p < .001]). The discriminatory abilities (Harrell's C-statistic) for BUN, eGFR and creatinine were 0.75, 0.76 and 0.67, respectively. The addition of BUN to eGFR significantly improved the C-statistic (0.78, p for comparison = 0.017), net reclassification (23.7%, p < .001) and integrated discrimination (2.9%, p < .001). CONCLUSIONS: Circulating BUN on admission is an independent predictor of long-term cardiovascular mortality in AMI patients and adds predictive power beyond eGFR. BUN reflects not only kidney function, but also acute haemodynamic and neurohumoral alterations during AMI, and may help to identify high-risk patients.

De-Ritis Ratio Improves Long-Term Risk Prediction after Acute Myocardial Infarction.

BACKGROUND: Recent evidence suggested levels of aspartate aminotransferase (AST), alanine transaminase (ALT), and AST/ALT ratio (De-Ritis ratio) were associated with a worse outcome after acute myocardial infarction (AMI). However, their value for predicting long-term prognosis remained unknown. Therefore, we investigated the prognostic potential of transaminases on patient outcome after AMI from a long-term perspective. METHODS: Data of a large AMI registry including 1355 consecutive patients were analyzed. The Cox regression hazard analysis was used to assess the impact of transaminases and the De-Ritis ratio on long-term mortality. RESULTS: The median De-Ritis ratio for the entire study population was 1.5 (interquartile range [IQR]: 1.0⁻2.6). After a median follow-up time of 8.6 years, we found that AST (crude hazard ratio (HR) of 1.19 per 1-SD [95% confidence interval (CI): 1 .09⁻1.32; p < 0.001]) and De-Ritis ratio (crude HR of 1.31 per 1-SD [95% CI: 1.18⁻1.44; p < 0.001]), but not ALT (p = 0.827), were significantly associated with long-term mortality after AMI. After adjustment for confounders independently, the De-Ritis ratio remained a strong and independent predictor for long-term mortality in the multivariate model with an adjusted HR of 1.23 per 1-SD (95% CI: 1.07⁻1.42; p = 0.004). Moreover, the De-Ritis ratio added prognostic value beyond N-terminal pro-B-Type Natriuretic Peptide, Troponin T, and Creatine Kinase. CONCLUSION: The De-Ritis ratio is a strong and independent predictor for long-term mortality after AMI. As a readily available biomarker in clinical routine, it might be used to identify patients at risk for fatal cardiovascular events and help to optimize secondary prevention strategies after AMI.

Gender and age-specific aspects of awareness and knowledge in basic life support.

BACKGROUND: The 'chain of survival'-including early call for help, early cardiopulmonary resuscitation (CPR) and early defibrillation-represents the most beneficial approach for favourable patient outcome after out-of-hospital cardiac arrest (OHCA). Despite increasing numbers of publicly accessible automated external defibrillators (AED) and interventions to increase public awareness for basic life support (BLS), the number of their use in real-life emergency situations remains low. METHODS: In this prospective population-based cross-sectional study, a total of 501 registered inhabitants of Vienna (Austria) were randomly approached via telephone calls between 08/2014 and 09/2014 and invited to answer a standardized questionnaire in order to identify public knowledge and awareness of BLS and AED-use. RESULTS: We found that more than 52 percent of participants would presume OHCA correctly and would properly initiate BLS attempts. Of alarming importance, only 33 percent reported that they would be willing to perform CPR and 50 percent would use an AED device. There was a significantly lower willingness to initiate BLS attempts (male: 40% vs. female: 25%; OR: 2.03 [95%CI: 1.39-2.98]; p<0.001) and to use an AED device (male: 58% vs. female: 44%; OR: 1.76 [95%CI: 1.26-2.53]; p = 0.002) in questioned female individuals compared to their male counterparts. Interestingly, we observed a strongly decreasing level of knowledge and willingness for BLS attempts (-14%; OR: 0.72 [95%CI: 0.57-0.92]; p = 0.027) and AED-use (-19%; OR: 0.68 [95%CI: 0.54-0.85]; p = 0.001) with increasing age. CONCLUSION: We found an overall poor knowledge and awareness concerning BLS and the use of AEDs among the Viennese population. Both female and elderly participants reported the lowest willingness to perform BLS and use an AED in case of OHCA. Specially tailored programs to increase awareness and willingness among both the female and elderly community need to be considered for future educational interventions.

CD4+CD28null T Lymphocytes are Associated with the Development of Atrial Fibrillation after Elective Cardiac Surgery.

Post-operative atrial fibrillation (POAF) is postulated as a complex interaction of different pathogenic factors, suggesting inflammatory processes as a main trigger of this particular type of atrial fibrillation. Therefore, the study sought to assess the impact of cellular immunity on the development of POAF. Comparing patients developing POAF to individuals free of POAF the fraction of CD4+CD28null T Lymphocytes was significantly higher in individuals developing POAF (11.1% [POAF] vs. 1.9% [non-POAF]; p < 0.001). CD4+CD28null cells were independently associated with the development of POAF with an adjusted odds ratio per one standard deviation of 4.89 (95% CI: 2.68-8.97; p < 0.001). Compared to N-terminal Pro-Brain Natriuretic Peptide, the fraction of CD4+CD28null cells demonstrated an increased discriminatory power for the development of POAF (NRI: 87.9%, p < 0.001; IDI: 30.9%, p < 0.001). Interestingly, a pre-operative statin-therapy was associated with a lower fraction of CD4+CD28null cells (p < 0.001) and showed an inverse association with POAF (p < 0.001). CD4+CD28null cells proved to be predictive for the development of POAF after cardiac surgery. Our results potentially indicate an auto-immune impact of this preexisting, highly cytotoxic T cell subset in the pathogenesis of POAF, which might be modified via the anti-inflammatory potential of a pre-operative statin-therapy.