New-Onset Atrial Fibrillation After Cardiac Surgery is a Significant Risk Factor for Long-Term Stroke: An Eight-Year Prospective Cohort Study

Usefulness of the C2HEST score to predict new onset atrial fibrillation. A systematic review and meta-analysis on >11 million subjects

BACKGROUND

The incidence of new-onset atrial fibrillation (NOAF) is increasing in the last decades. NOAF is associated with worse long-term prognosis. The C2HEST score has been recently proposed to stratify the risk of NOAF. Pooled data on the performance of the C2HEST score are lacking.

METHODS

Systematic review and meta-analysis of observational studies reporting data on NOAF according to the C2HEST score. We searched PubMed, Web of Science and Google scholar databases without time restrictions until June 2023 according to PRISMA guidelines. Meta-analysis of the area under the curve (AUC) with 95% confidence interval (95% CI) and a sensitivity analysis according to setting of care and countries were performed.

RESULTS

Of 360 studies, 17 were included in the analysis accounting for 11,067,496 subjects/patients with 307,869 NOAF cases. Mean age ranged from 41.3 to 71.2 years. The prevalence of women ranged from 10.6 to 54.75%. The pooled analysis gave an AUC of .70 (95% CI .66-.74). A subgroup analysis on studies from general population/primary care yielded an AUC of 0.69 (95% CI 0.64-0.75). In the subgroup of patients with cardiovascular disease, the AUC was .71 (.69-.79). The C2HEST score performed similarly in Asian (AUC .72, 95% CI .68-.77), and in Western patients (AUC .68, 95% CI .62-.75). The best performance was observed in studies with a mean age <50 years (n = 3,144,704 with 25,538 NOAF, AUC .78, 95% CI .76-.79).

CONCLUSION

The C2HEST score may be used to predict NOAF in primary and secondary prevention patients, and in patients across different countries. Early detection of NOAF may aid prompt initiation of management and follow-up, potentially leading to a reduction of AF-related complications.

Postoperative atrial fibrillation in mitral valve surgery is not benign

OBJECTIVE

Postoperative atrial fibrillation (POAF) is common after cardiac surgery and is often considered to be benign despite recent data suggesting worse outcomes. There are no guidelines for the amount of POAF that triggers anticoagulation or for postoperative surveillance. We examined the rate of POAF, incidence of neurologic events, development of permanent atrial fibrillation, and mortality in patients undergoing isolated mitral valve surgery at a Mitral Foundation reference center.

METHODS

This is a retrospective cohort study of 922 adult patients from 2011 to 2022 with no preoperative history of arrhythmias. Multivariable logistic regression was used to identify independent risk factors for the primary outcomes. Kaplan-Meier analysis and Cox proportional-hazards model were used to characterize long-term survival.

RESULTS

The incidence of POAF was 39%. Median follow-up was 4.9 months (interquartile range, 1.1-42.6 months). Diabetes (odds ratio [OR], 2.2; 95% CI, 1.2-4.1; P = .01) and increasing age (OR, 1.1; 95% CI, 1.0-1.1; P < .001) were risk factors for POAF, whereas New York Heart Association functional class was not. POAF was a risk factor for the development of permanent atrial fibrillation (OR, 3.2; 95% CI 1.9-5.4; P < .001), which was associated with increased risk of neurologic events (OR, 3.8; 95% CI, 1.5-9.7; P = .004). Ultimately, patients with POAF had worse unadjusted (P < .001) and adjusted long-term mortality (hazard ratio, 1.8; 95% CI, 1.1-3.1; P = .03).

CONCLUSIONS

POAF is associated with an increased rate of neurologic events, portends development of permanent atrial fibrillation, and is associated with worse long-term survival. POAF is not benign and carries a long-term mortality implication.

Differences in Postoperative Atrial Fibrillation Incidence and Outcomes After Cardiac Surgery According to Assessment Method and Definition: A Systematic Review and Meta-Analysis

BACKGROUND

Postoperative atrial fibrillation (POAF) is the most frequent complication of cardiac surgery. Despite clinical and economic implications, ample variability in POAF assessment method and definition exist across studies. We performed a study-level meta-analysis to evaluate the influence of POAF assessment method and definition on its incidence and association with clinical outcomes.

METHODS AND RESULTS

A systematic literature search was conducted to identify studies comparing the outcomes of patients with and without POAF after cardiac surgery that also reported POAF assessment method. The primary outcome was POAF incidence. The secondary outcomes were in-hospital mortality, stroke, intensive care unit length of stay, and postoperative length of stay. Fifty-nine studies totaling 197 774 patients were included. POAF cumulative incidence was 26% (range: 7.3%-53.1%). There were no differences in POAF incidence among assessment methods (27%, [range: 7.3%-53.1%] for continuous telemetry, 27% [range: 7.9%-50%] for telemetry plus daily ECG, and 19% [range: 7.8%-42.4%] for daily ECG only; P>0.05 for all comparisons). No differences in in-hospital mortality, stroke, intensive care unit length of stay, and postoperative length of stay were found between assessment methods. No differences in POAF incidence or any other outcomes were found between POAF definitions. Continuous telemetry and telemetry plus daily ECG were associated with higher POAF incidence compared with daily ECG in studies including only patients undergoing isolated coronary artery bypass grafting.

CONCLUSIONS

POAF incidence after cardiac surgery remains high, and detection rates are variable among studies. POAF incidence and its association with adverse outcomes are not influenced by the assessment method and definition used, except in patients undergoing isolated coronary artery bypass grafting.

Microvascular dysfunction following cardiopulmonary bypass plays a central role in postoperative organ dysfunction

Despite significant advances in surgical technique and strategies for tissue/organ protection, cardiac surgery involving cardiopulmonary bypass is a profound stressor on the human body and is associated with numerous intraoperative and postoperative collateral effects across different tissues and organ systems. Of note, cardiopulmonary bypass has been shown to induce significant alterations in microvascular reactivity. This involves altered myogenic tone, altered microvascular responsiveness to many endogenous vasoactive agonists, and generalized endothelial dysfunction across multiple vascular beds. This review begins with a survey of in vitro studies that examine the cellular mechanisms of microvascular dysfunction following cardiac surgery involving cardiopulmonary bypass, with a focus on endothelial activation, weakened barrier integrity, altered cell surface receptor expression, and changes in the balance between vasoconstrictive and vasodilatory mediators. Microvascular dysfunction in turn influences postoperative organ dysfunction in complex, poorly understood ways. Hence the second part of this review will highlight in vivo studies examining the effects of cardiac surgery on critical organ systems, notably the heart, brain, renal system, and skin/peripheral tissue vasculature. Clinical implications and possible areas for intervention will be discussed throughout the review.

Recent advances and perspectives of postoperative neurological disorders in the elderly surgical patients

Postoperative neurological disorders, including postoperative delirium (POD), postoperative cognitive dysfunction (POCD), postoperative covert ischemic stroke, and hemorrhagic stroke, are challenging clinical problems in the emerging aged surgical population. These disorders can deteriorate functional outcomes and long‐term quality of life after surgery, resulting in a substantial social and financial burden to the family and society. Understanding predisposing and precipitating factors may promote individualized preventive treatment for each disorder, as several risk factors are modifiable. Besides prevention, timely identification and treatment of etiologies and symptoms can contribute to better recovery from postoperative neurological disorders and lower risk of long‐term cognitive impairment, disability, and even death. Herein, we summarize the diagnosis, risk factors, prevention, and treatment of these postoperative complications, with emphasis on recent advances and perspectives.