Preoperative Brain Natriuretic Peptide and Atrial Arrhythmias After Coronary Artery Bypass Graft Surgery

Preoperative B-Type Natriuretic Peptides to Predict Postoperative Atrial Fibrillation in Cardiac Surgery: A Systematic Review and Meta-Analysis

BACKGROUND

Post-operative atrial fibrillation (AF) is the most common complication following cardiac surgery. There has been extensive exploration of clinical variables, imaging, and biomarkers to predict its occurrence after cardiac surgery. In this study, we examine the emerging biomarkers B-type natriuretic peptide (BNP) and N-terminal proBNP (NT-proBNP) to assess their pre-operative values and correlations with the occurrence of post-operative AF in patients undergoing cardiac surgery.

METHODS

A comprehensive literature search was conducted using PubMed, EMBASE, MEDLINE via Ovid, ClinicalTrials.Gov, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) to identify studies published until March 2023. The studies were included if they reported pre-operative BNP or NT-proBNP values and the development of post-operative AF in cardiac surgery patients. Subsequently, data were extracted, and a meta-analysis was performed using Review Manager 5.4 4 (The Cochrane Collaboration, 2020) and SPSS version 28 (IBM Corp, Armonk, NY, USA) to assess the difference between pre-operative BNP and NT-proBNP levels between patients with post-operative AF (AF group) and those without (No-AF group) using a random-effect model. Further analysis was performed in three subgroups: isolated coronary artery bypass grafting, isolated valve, and combined/mixed surgery group.

RESULT

A total of 20 studies, including 9,079 participants were identified and included in the systematic review and meta-analysis. Pre-operative BNP levels were reported in 11 studies, and NT-proBNP levels were reported in 10 studies, of which one study reported both BNP and NT-proBNP levels. There is an overall significant difference between pre-operative levels of BNP (p=0.03, I2=95%) and NT-proBNP (p<0.001, I2=65%) when compared between AF and No-AF groups. Nonetheless, subgroup analysis showed there is no significant difference in pre-operative BNP levels, except in isolated valve surgery (p<0.001), whereas all subgroups showed significantly different pre-operative levels of NT-proBNP.

CONCLUSIONS

Elevated levels of both BNP and NT-proBNP were observed in patients who developed post-operative AF after undergoing cardiac surgery. In particular, pre-operative NT-proBNP levels were elevated in all patients irrespective of the type of surgical procedure, but elevated pre-operative BNP was only seen in valve surgery patients. These findings suggest the potential usefulness of NT-proBNP as a promising biomarker for predicting the occurrence of post-operative AF following cardiac surgery.

The Role of Natriuretic Peptides in Predicting Adverse Outcomes After Cardiac Surgery: An Updated Systematic Review

The increasing global burden of cardiovascular disease, particularly, in the aging population, has led to an increase in high-risk cardiac surgical procedures. The current preoperative risk stratification scores, such as the European System for Cardiac Operative Risk Evaluation and the Society for Thoracic Surgeons score, have limitations in their predictive accuracy and tend to underestimate the mortality risk in higher-risk populations. This systematic review aimed to evaluate the utility of natriuretic peptides, brain natriuretic peptide (BNP) and its precursor prohormone (N-terminal prohormone BNP), as predictive biomarkers for adverse outcomes after cardiac surgery. A comprehensive search strategy was performed, and 63 studies involving 40,667 patients who underwent major cardiac operations were included for data extraction. Preoperative levels of BNP and N-terminal prohormone BNP seemed to be associated with an increased risk of short- and long-term mortality, postoperative heart failure, kidney injury, and length of intensive care unit stay. However, their predictive value for postoperative arrhythmias and myocardial infarction was less established. Our findings suggest that natriuretic peptides may play an important role in risk prediction in patients who underwent cardiac surgery. The addition of these biomarkers to the existing clinical risk stratification strategies may enhance their predictive accuracy. However, this needs to be endorsed by data derived from wide-scale clinical trials.

Natriuretic Peptides in Cardiac Anesthesia and Intensive Care

Natriuretic peptides, predominantly B-type, are widely used in cardiology as prognostic and diagnostic biomarkers or, much less often, as a substantive treatment tool. They are hormones that are produced mainly in the myocardium in response to overload and ischemia, and their level quite accurately reflects the degree of myocardial dysfunction. Although their use in cardiac anesthesia and intensive care setting seems to be very beneficial for assessing the risk of acute disturbance of myocardial function or its laboratory monitoring, the actual significance of natriuretic peptides in this area is not yet recognized. This is due to the lack of clear diagnostic and prognostic values for these biomarkers supported by high-quality researches. On the basis of the available data, main advantages, existing difficulties, and most effective ways of using natriuretic peptides for determining the risk of heart surgery and assessing the severity of sepsis, pneumonia, and other critical conditions have been discussed in this review. In addition, the expediency of using natriuretic peptides as target parameters for goal-oriented therapy and as a substantive tool for treatment is considered.

B-Type Natriuretic Peptide as a Predictor of Short-Term Mortality in On-Pump Coronary Artery Bypass Grafting

Objective

The present study refers to a determination of the preoperative B-type natriuretic peptide is a predictor of short-term all-cause mortality in patients undergoing on-pump coronary artery bypass graft surgeries.

Methods

Two hundred and twenty-one patients undergoing on-pump coronary artery bypass graft surgeries were evaluated prospectively during a 30-day postoperative follow-up period. Serum B-type natriuretic peptide concentration was measured without a 24-hour period prior to the surgical procedure and the value obtained was correlated with a short-term all-cause mortality.

Results

Data analysis showed that all-cause mortality rates were equal to 9.5% in 30 days. Accuracy analysis by the receiver operating characteristic curve found an ideal cut-off value of B-type natriuretic peptide equal to 150 pg/mL in relation to mortality (AUC=0.82, 95% CI=0.71-0.87, P<0.001). Multivariate analysis showed that B-type natriuretic peptide value greater than or equal to 150 pg/mL (P=0.030, HR=3.99, 95% CI=1.14-13.98) was an independent predictor of all-cause mortality in a 30-day follow-up period.

Conclusion

Preoperative serum B-type natriuretic peptide concentration is an independent predictor of short-term all-cause mortality in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass.