Background Postoperative atrial fibrillation (POAF) is assumed as a complex and multifactorial interaction of different pathogenic factors. Data suggests an inflammatory process as the main trigger of this specific type of atrial fibrillation. CD8⁺ T lymphocytes that lack the surface protein CD28 were found to be crucially involved in chronic inflammatory processes within the cardiovascular system. Of utmost interest, these so-called CD8⁺CD28^null T cells are known to present with autoaggressive behavior and deleterious cytotoxic effects on human tissue. Methods A total of 129 patients undergoing elective cardiac valve and/or coronary artery bypass graft surgery were enrolled. Fluorescence-activated cell sorting was performed to investigate lymphocyte subsets. Patients were stratified in two subgroups according to patients developing POAF (n = 60) and individuals free of POAF (n = 69). Results Comparing patients developing POAF to individuals free of POAF, the fraction of CD8⁺ lymphocytes was significantly higher in individuals developing POAF (30.5% [POAF] vs. 25.7% [no-POAF]; p = 0.021). Interestingly, also the fraction of CD8⁺CD28^null T lymphocytes was significantly higher in the POAF subgroup (66.7% [POAF] vs. 61.6% [non-POAF]; p = 0.043). Multivariate logistic regression proved that the fraction of CD8⁺CD28^null cells is a strong and independent prognosticator for the development of POAF with an adjusted odds ratio per 1 standard deviation of 3.21 (95% confidence interval 1.01–10.18; p = 0.048). Conclusion We found that cytotoxic CD8⁺CD28^null T lymphocytes proved to be a strong and independent predictor for the development of POAF after elective cardiac surgery. Our results potentially indicate an autoimmune impact of this preexisting, highly cytotoxic T cell subset in the pathogenesis of POAF. Received: 26 February 2020 Accepted: 01 May 2020 Publication Date: 28 June 2020 (online) Georg Thieme Verlag KG Stuttgart · New York

Nosocomial infections are a common complication in clinical practice with major impact on surgical success and patient outcome. The probability of nosocomial infections is rapidly increasing during hospitalization. Therefore, we investigated the impact of a prolonged pre-operative hospital stay on the development of post-operative infection. Within this prospective observational study, 200 patients scheduled for elective cardiac surgery were enrolled. Patients were followed during hospital admission and screened for the development of nosocomial infection. Logistic regression analysis was used to assess the impact of a prolonged pre-operative hospital stay on the development of infection. A total of 195 patients were suitable for the final analysis. We found a strong and direct association of the duration of pre-operative hospital stay and the number of patients developing infection (+23.5%; p = 0.006). Additionally, the length of patients’ pre-operative hospital stay was independently associated with the development of post-operative nosocomial infection, with an adjusted OR per day of 1.38 (95%CI: 1.02–1.86; p = 0.036). A prolonged pre-operative hospital stay was significantly associated with the development of nosocomial infection after cardiac surgery. Those findings need to be considered in future clinical patient management in order to prevent unnecessary antibiotic use and potential harm to patients.

Aims: Direct oral anticoagulants (DOACs) are increasingly used off-label to treat patients with left ventricular thrombus (LVT). We analysed available meta-data comparing DOACs and vitamin K antagonists (VKAs) for efficacy and safety. Methods: We conducted a systematic search and meta-analysis of observational and randomized data comparing DOACs vs. VKAs in patients with LVT. Endpoints of interest were stroke or systemic embolism, thrombus resolution, all-cause death, and a composite bleeding endpoint. Estimates were pooled using a random-effects model meta-analysis, and their robustness was investigated using sensitivity and influential analyses. Results: We identified 22 articles (18 observational studies, 4 small randomized clinical trials) reporting on a total of 3587 patients (2489 VKA vs. 1098 DOAC therapy). The pooled estimates for stroke or systemic embolism [odds ratio (OR): 0.81; 95% confidence interval (CI): 0.57, 1.15] and thrombus resolution (OR: 1.12; 95% CI: 0.86, 1.46) were comparable, and there was low heterogeneity overall across the included studies. The use of DOACs was associated with lower odds of all-cause death (OR: 0.65; 95% CI: 0.46, 0.92) and a composite bleeding endpoint (OR: 0.67; 95% CI: 0.47, 0.97). A risk of bias was evident particularly for observational reports, with some publication bias suggested in funnel plots. Conclusion: In this comprehensive analysis of mainly observational data, the use of DOACs was not associated with a significant difference in stroke or systemic embolism, or thrombus resolution, compared with VKA therapy. The use of DOACs was associated with a lower rate of all-cause death and fewer bleeding events. Adequately sized randomized clinical trials are needed to confirm these findings, which could allow a wider adoption of DOACs in patients with LVT.

Personalized risk stratification within the ageing society after acute coronary syndrome (ACS) remains scarce but in urgent need. Increased platelet activity together with inflammatory activation play a key role during ACS. We aimed to evaluate the age-specific prognostic potential of the platelet to lymphocyte ratio (PLR) on long-term cardiovascular mortality after ACS. Patients presenting with ACS admitted to the Vienna General Hospital between December 1996 and January 2010 were enrolled within a clinical registry including assessment of peripheral blood samples. The impact of the PLR on survival was assessed by Cox-regression hazard analysis. We included a total of 681 patients with a median age of 64 years (interquartile range: 45–84). Two hundred (29.4%) individuals died during the median follow-up time of 8.5 years. A strong and independent association of the PLR with cardiovascular mortality was found in the total study population [adjusted (adj.) hazard ratio (HR) per 1 standard deviation (1 SD) of 1.07 (95% confidence interval, CI: 1.03–1.10); P < 0.001]. After stratification in individuals <65 years (n = 339) and ≥65 years (n = 342), a prognostic effect of the PLR on cardiovascular mortality was solely observed in elderly patients ≥65 years [adj. HR per 1 SD of 1.04 (95% CI: 1.00–1.08); P = 0.039], but not in their younger counterparts <65 years [adj. HR per 1 SD of 0.97 (95% CI: 0.83–1.14); P = 0.901]. The present investigation highlights a strong and independent age-specific association of the PLR with cardiovascular mortality in patients with ACS. The PLR only allows to identify patients ≥65 years at high risk for fatal events after ACS—even from a long-term perspective.

Background. Heart failure with reduced ejection fraction (HFrEF) constitutes a global health issue. While proinflammatory cytokines proved to have a pivotal role in the development and progression of HFrEF, less attention has been paid to the cellular immunity. Regulatory T lymphocytes (Tregs) seem to have an important role in the induction and maintenance of immune homeostasis. Therefore, we aimed to investigate the impact of Tregs on the outcome in HFrEF. Methods. We prospectively enrolled 112 patients with HFrEF and performed flow cytometry for cell phenotyping. Individuals were stratified in ischemic (iHFrEF, n=57) and nonischemic etiology (niHFrEF, n=55). Cox regression hazard analysis was used to assess the influence of Tregs on survival. Results. Comparing patients with iHFrEF to niHFrEF, we found a significantly lower fraction of Tregs within lymphocytes in the ischemic subgroup (0.42% vs. 0.56%; p=0.009). After a mean follow-up time of 4.5 years, 32 (28.6%) patients died due to cardiovascular causes. We found that Tregs were significantly associated with cardiovascular survival in the entire study cohort with an adjusted HR per one standard deviation (1-SD) of 0.60 (95% CI: 0.39-0.92; p=0.017). A significant inverse association of Tregs and cardiovascular mortality in patients with iHFrEF with an adj. HR per 1-SD of 0.59 (95% CI: 0.36-0.96; p=0.034) has been observed, while this association was not evident in the nonischemic subgroup (adj. HR per 1-SD of 0.62 (95% CI: 0.17-2.31); p=0.486). Conclusion. Our results indicate a potential influence of Tregs in the pathogenesis and progression of iHFrEF, fostering the implication of cellular immunity in iHFrEF pathophysiology and proving Tregs as a predictor for long-term survival among iHFrEF patients. A preview of this study has been presented at a meeting of the European Society of Cardiology earlier this year.

Background GDF-15 (growth/differentiation factor 15) is induced by myocardial stretch, volume overload, inflammation, and oxidative stress. Its expression is tightly linked with cardiovascular events as well as the risk for major bleeding and all-cause mortality. The present study aimed to elucidate the prognostic potential of GDF-15 in patients after cardiac surgery. Methods A total of 504 patients undergoing elective cardiac valve and/or coronary artery bypass graft surgery were prospectively enrolled. GDF-15 levels were measured prior to surgery to evaluate the impact on bleeding events, thromboembolic events, and mortality. Results Preoperative GDF-15 was associated with the primary endpoint of intra- and postoperative red blood cell transfusion (for bleeding risk factors adjusted [adj] OR [odds ratio] per 1-SD [standard deviation] of 1.62 [95% confidence interval [CI]: 1.31–2.00]; p < 0.001). Higher concentrations of GDF-15 were observed in patients reaching the secondary endpoint of major or clinically relevant minor bleeding (for bleeding risk factors adj. OR per 1-SD of 1.70 [95% CI: 1.05–2.75]; p = 0.030) during the first postoperative year, but not for thromboembolic events. GDF-15 was a predictor for cardiovascular mortality (for comorbidities adj. HR [hazard ratio] per 1-SD of 1.67 [95% CI: 1.23–2.27]; p = 0.001) and all-cause mortality (for comorbidities adj. HR per 1-SD of 1.55 [95% CI: 1.19–2.01]; p = 0.001). A combined risk model of GDF-15 and EuroSCORE II outperformed the EuroSCORE II alone for long-term survival (C-index: 0.75 [95% CI: 0.70–0.80], p = 0.046; net reclassification improvement: 33.6%, p < 0.001). Conclusion Preoperative GDF-15 concentration is an independent predictor for intra- and postoperative major bleeding, major bleeding during the first year, and for long-term cardiovascular or all-cause mortality after cardiac surgery.