Galectin-3 as a Predictor of Post Cardiac Surgery Atrial Fibrillation: A Scoping Review

Galectin-3 is associated with myocardial fibrosis, a known risk factor for developing re-entrant circuits associated with atrial fibrillation (AF). Previous studies have demonstrated increased galectin levels in AF patients. Whether preoperative galectin-3 levels can predict the incidence of postoperative atrial fibrillation (POAF) remains unknown.This scoping review was conducted in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Electronic searches were conducted in Medline, EMBASE, Cochrane, and Google Scholar databases using a predetermined strategy. Methodological variables, demographics and operative data were extracted. Data extraction was performed manually by 3 reviewers.The search yielded 620 citations, of which 74 underwent full text review, and 3 citations with 3 independent samples (n=1812) met full inclusion/exclusion criteria and were included. Of the 3 studies that reported on the association between preoperative galectin-3 levels and POAF, 2 studies compared median galectin levels in patients who developed POAF and those who did not. While Alexandre et al. reported a significant difference (P=0.002), Bening et al did not find a significant difference between POAF and non-POAF groups (P=0.3). A third study reporting on the association between galectin-3 and atrial fibrillation comparing third and first tercile galectin-3 levels found a significant association between preoperative galectin levels and POAF on univariate analysis (OR 1.54; 95% CI 1.14-2.09).Galectin-3 is an emerging biomarker that has been associated with the development of AF. However, there is currently not enough evidence to establish its prognostic role in postcardiac surgery atrial fibrillation.Fil: King, Morgan. Queens University; CanadáFil: Stambulic, Thomas. Queens University; CanadáFil: Kirupaharan, Sawmmiya. Queens University; CanadáFil: Baranchuk, Adrian. Queens University; CanadáFil: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Payne, Darrin. Queens University; CanadáFil: El Diasty, Mohammad. Queens University; Canad

The histology of human right atrial tissue in patients with high-risk Obstructive Sleep Apnea and underlying cardiovascular disease: A pilot study

Obstructive Sleep Apnea (OSA) results in intermittent hypoxia leading to atrial remodeling, which, among other things, facilitates development of atrial fibrillation. While much data exists on the macrostructural changes in cardiac physiology induced by OSA, there is a lack of studies looking for histologic changes in human atrial tissue induced by OSA which might lead to the observed macrostructural changes. A case control study was performed. Patients undergoing coronary artery bypass grafting (CABG) were evaluated for OSA and categorized as high-risk or low-risk. The right atrial tissue samples were obtained during CABG and both microscopic histological analysis and Sirius Red staining were performed. 18 patients undergoing CABG were included, 10 high-risk OSA and 8 low-risk OSA in evenly matched populations. No statistically significant difference between the two groups was observed in amount of myocytolysis (p = 0.181), nuclear hypertrophy (p = 0.671), myocardial inflammation (p = n/a), amyloid deposition (p = n/a), or presence of thrombi (p = n/a), as measured through routine H&E staining. As well, no statistically significant difference in interstitial and epicardial collagen was observed, as measured by Sirius Red staining (for total tissue: p = 0.619: for myocardium: p = 0.776). In this pilot study there were no observable histological differences in human right atrial tissue from individuals at high- and low-risk for OSA. Further investigation would be required for more definitive results

Hemodynamic performance of stentless versus stented valves: a systematic review and meta-analysis

BACKGROUND: Several trials have compared stentless with stented valves following aortic valve replacement (AVR). The goal of this review was to systematically locate, critically appraise, and quantitatively combine results to determine if stentless valves improve cardiac hemodynamics. METHODS: We performed an unrestricted search of Pubmed Medline, EMBASE, CINAHL, the Cochrane databases, and EBM reviews. Article reference lists and online abstracts from major North American conferences were also searched. We included randomized trials of adults undergoing AVR that compared stentless and stented valves. Blinded reviewers performed assessment of trials for inclusion and trial quality. Two individuals performed data extraction independently. Kappa statistics were used to assess reviewer agreement. A random effects model was employed for statistical analyses. Assessments were made for postoperative, early, and late outcomes. Heterogeneity was explored with sensitivity analyses. RESULTS: Eight studies were identified for inclusion in the primary analysis, with four others included in sensitivity analyses. Baseline comparisons between groups revealed no differences. Our primary analyses revealed no differences between groups for assessments of LV mass or mean transvalvar gradients. Secondary analyses showed stentless valves to have lower peak gradients. Sensitivity analyses were supportive of our primary results. Heterogeneity was observed in some comparisons and sensitivity analyses failed to completely explain this heterogeneity. CONCLUSIONS: Stentless valves did not display hemodynamic benefit in terms of LV mass regression or postoperative mean gradients, but do appear to display superior hemodynamics in terms of peak gradients. Further well-designed and adequately powered trials are required to fully address this question