Outcomes After Left Atrial Appendage Clip Placement During Cardiac Surgery: A Nationwide Analysis.

This study evaluated the nationwide associations between concomitant left atrial appendage clip (LAAC) placement during cardiac surgery and postoperative outcomes. We identified 1,260,999 patients who underwent coronary artery bypass grafting, valve, and aortic surgeries in the 2016 to 2020 Nationwide Readmissions Database and stratified by concomitant LAAC versus no LAAC placement. Patients who underwent surgical ablation were excluded. Mortality and complications were compared during index admissions and for patients readmitted within 30 and 90 days of the index discharge date for unmatched and propensity score-matched groups. Overall, 6.7% (84,293) of patients underwent cardiac surgery and concomitant LAAC placement without surgical ablation. After propensity score matching, the index admission mortality and overall complications were not different in patients with LAAC versus patients without LAAC. LAAC placement was associated with increased any-cause 30-day readmissions (15% vs 13%, p <0.01). In patients with LAAC, within 30 days, there were no differences in mortality (3.9% vs 3.8%, p = 0.60) or overall complications (64% vs 63%, p = 0.20), whereas stroke was lower (5.3% vs 6.5%, p <0.01) and heart failure was higher (35% vs 30%, p <0.01). For patients readmitted within 90 days, similar findings were observed for any-cause readmissions, mortality, overall complications, stroke, and heart failure. In conclusion, concomitant LAAC placement during cardiac surgery was associated with lower early postdischarge incidence of stroke and a favorable overall risk-benefit profile. Given these short-term findings in a real-world population of all patients who underwent cardiac surgery, longer-term studies with more granular data are needed to evaluate the potential benefit of this practice.

Trends in surgical ablation at the time of cardiac surgery among patients with atrial fibrillation.

Background: The 2017 American Association for Thoracic Surgery (AATS) guidelines support surgical ablation in patients undergoing cardiac surgery with preoperative atrial fibrillation (AF) owing to a reduction in early mortality and improved overall safety. We explored practice patterns changes and outcomes in patients undergoing concomitant surgical ablation following the guideline change. Methods: We identified 19,246 patients with preoperative AF who underwent cardiac surgery between 2016 and 2019 from the Florida and Maryland State Inpatient Databases. Rates of surgical ablation by procedure type were temporally trended across years. Secondary outcomes included complications, inpatient mortality, and hospital readmissions. Using multivariable logistic regression, we identified patient variables associated with concomitant surgical ablation. Results: A total of 2738 patients (14.3%) with AF underwent a concomitant surgical ablation. The rate of surgical ablation increased from 2.1% to 17.4% (P < .001) from 2016 to 2017 but remained unchanged thereafter. Postoperative mortality was lower in the surgical ablation cohort (2.7% vs 3.7%; P = .006), although with a higher rate of pacemaker insertion (11.8% vs 7.2%; P < .0001). Patients with a high-risk Elixhauser score (odds ratio [OR], 0.83; 95% confidence interval [CI], 0.73-0.95), lower income (OR, 0.66; 95% CI, 0.57-0.75), or African American or Hispanic race/ethnicity (OR, 0.80; 95% CI, 0.67-0.96 and OR, 0.82; 95% CI, 0.71-0.96, respectively) had lower odds of undergoing concomitant surgical ablation. Conclusions: Despite a class I-2a recommendation by the AATS, surgical ablation continues to be underutilized in clinical practice, especially in patients with high-risk comorbidities, with lower incomes, or from minority populations. Surgeons should be mindful of guideline-directed AF management in these vulnerable populations.

Per-Oral Endoscopic Myotomy for Esophagogastric Junction Outflow Obstruction: A Multicenter Pilot Study.

Esophagogastric junction outflow obstruction (EGJOO) is a rare but increasingly recognized diagnosis as described by The Chicago Classification of Esophageal Motility Disorders version 3.0 (version 3.0).1 On high-resolution manometry (HRM), EGJOO is characterized by increased integrated relaxation pressure (IRP) of the lower esophageal sphincter (LES), yet with some preserved esophageal peristalsis.2-4 Little consensus exists on the preferred therapeutic approach.3 Although conceptually per-oral endoscopic myotomy (POEM) should address the measurable dysfunction in the LES, few data exist to support this.5 Thus, we aimed to evaluate the safety and efficacy of POEM for the treatment of symptomatic EGJOO.

Endothelin-1 in the pathophysiology of obesity and insulin resistance.

The association between plasma endothelin-1 (ET-1) and obesity has been documented for decades, yet the contribution of ET-1 to risk factors associated with obesity is not fully understood. In 1994, one of first papers to document this association also noted a positive correlation between plasma insulin and ET-1, suggesting a potential contribution of ET-1 to the development of insulin resistance. Both endogenous receptors for ET-1, ETA and ETB are present in all insulin-sensitive tissues including adipose, liver and muscle, and ET-1 actions within these tissues suggest that ET-1 may be playing a role in the pathogenesis of insulin resistance. Further, antagonists for ET-1 receptors are clinically approved making these sites attractive therapeutic targets. This review focuses on known mechanisms through which ET-1 affects plasma lipid profiles and insulin signalling in these metabolically important tissues and also identifies gaps in our understanding of ET-1 in obesity-related pathophysiology.

Elevated plasma endothelin-1 is associated with reduced weight loss post vertical sleeve gastrectomy.

BACKGROUND: Obesity and insulin resistance are positively correlated with plasma endothelin-1 (ET-1) levels; however, the mechanisms leading to increased ET-1 are not understood. Similarly, the full physiological complexity of ET-1 has yet to be described, especially in obesity. To date, one of the best treatments available for morbid obesity is bariatric surgery to quickly reduce body fat and the factors associated with obesity-related disease; however, the effects of vertical sleeve gastrectomy (SG) on plasma ET-1 have not been described. OBJECTIVES: To determine if SG will reduce plasma ET-1 levels and to determine if plasma ET-1 concentration is associated with weight loss after surgery. SETTING: The studies were undertaken at a University Hospital. METHODS: This was tested by measuring plasma ET-1 levels from 12 obese patients before and after SG. All data were collected from clinic visits before SG, 6 weeks after SG, and 6 months after surgery. RESULTS: At 6 weeks after SG, plasma ET-1 levels increased by 24%; however, after 6 months, there was a 27% decrease compared with presurgery. Average weight loss in this cohort was 11.3% ± 2.4% body weight after 6 weeks and 21.4% ± 5.7% body weight after 6 months. Interestingly, we observed an inverse relationship between baseline plasma ET-1 and percent body weight loss (R2 = .49, P = .01) and change in body mass index 6 months (R2 = .45, P = .011) post bariatric surgery. CONCLUSIONS: Our results indicate that SG reduces plasma ET-1 levels, a possible mechanism for improved metabolic risk in these patients. These data also suggest that ET-1 may serve as a predictor of weight loss after bariatric surgery.

The Effect of Oxygen on Bile Resistance in Listeria monocytogenes.

Listeria monocytogenes is a Gram-positive facultative anaerobe that is the causative agent of the disease listeriosis. The infectious ability of this bacterium is dependent upon resistance to stressors encountered within the gastrointestinal tract, including bile. Previous studies have indicated bile salt hydrolase activity increases under anaerobic conditions, suggesting anaerobic conditions influence stress responses. Therefore, the goal of this study was to determine if reduced oxygen availability increased bile resistance of L. monocytogenes. Four strains representing three serovars were evaluated for changes in viability and proteome expression following exposure to bile in aerobic or anaerobic conditions. Viability for F2365 (serovar 4b), EGD-e (serovar 1/2a), and 10403S (serovar 1/2a) increased following exposure to 10% porcine bile under anaerobic conditions (P < 0.05). However, HCC23 (serovar 4a) exhibited no difference (P > 0.05) in bile resistance between aerobic and anaerobic conditions, indicating that oxygen availability does not influence resistance in this strain. The proteomic analysis indicated F2365 and EGD-e had an increased expression of proteins associated with cell envelope and membrane bioenergetics under anaerobic conditions, including thioredoxin-disulfide reductase and cell division proteins. Interestingly, HCC23 had an increase in several dehydrogenases following exposure to bile under aerobic conditions, suggesting that the NADH:NAD+ is altered and may impact bile resistance. Variations were observed in the expression of the cell shape proteins between strains, which corresponded to morphological differences observed by scanning electron microscopy. These data indicate that oxygen availability influences bile resistance. Further research is needed to decipher how these changes in metabolism impact pathogenicity in vivo and also the impact that this has on susceptibility of a host to listeriosis.