Preoperative blood urea nitrogen-to-left ventricular ejection fraction ratio is an independent predictor of long-term major adverse cardiac events in patients undergoing coronary artery bypass grafting surgery

Blood Urea Nitrogen to Left Ventricular Ejection Ratio as a Predictor of Short-Term Outcome in Acute Myocardial Infarction Complicated by Cardiogenic Shock

INTRODUCTION

Cardiogenic shock (CS) is the most critical complication after acute myocardial infarction (AMI) with mortality above 50%. Both blood urea nitrogen and left ventricular ejection fraction were important prognostic indicators. We aimed to evaluate the prognostic value of admission blood urea nitrogen to left ventricular ejection fraction ratio (BUNLVEFr) in patients with AMI complicated by CS (AMI-CS).

METHODS

268 consecutive patients with AMI-CS were divided into two groups according to the admission BUNLVEFr cut-off value determined by Youden index. The primary endpoint was 30-day all-cause mortality and the secondary endpoint was the composite events of major adverse cardiovascular events (MACEs). Cox proportional hazard models were performed to analyze the association of BUNLVEFr with the outcome.

RESULTS

The optimal cut-off value of BUNLVEFr is 16.63. The 30-day all-cause mortality and MACEs in patients with BUNLVEFr≥16.63 was significantly higher than in patients with BUNLVEFr<16.63 (30-day all-cause mortality: 66.2% vs. 17.1%, p < 0.001; 30-day MACEs: 80.0% vs. 48.0%, p < 0.001). After multivariable adjustment, BUNLVEFr≥16.63 remained an independent predictor for higher risk of 30-day all-cause mortality (HR = 3.553, 95% CI: 2.125-5.941, p < 0.001) and MACEs (HR = 2.026, 95% CI: 1.456-2.820, p < 0.001). Subgroup analyses found that the effect of BUNLVEFr was consistent in different subgroups (all p-interaction>0.05).

CONCLUSION

The admission BUNLVEFr provided important prognostic information for AMI-CS patients.

Blood Urea Nitrogen-to-Albumin Ratio in Predicting Long-Term Mortality in Patients Following Coronary Artery Bypass Grafting: An Analysis of the MIMIC-III Database

Background

This study examined the role of blood urea nitrogen-to-albumin ratio (BAR) in predicting long-term mortality in patients undergoing coronary artery bypass grafting (CABG).

Methods

In this retrospective cohort study, patients undergoing CABG were enrolled from the Medical Information Mart for Intensive Care III (MIMIC III) database. Patients were divided into the three groups according to the optimal cutoff values of BAR determined by X-tile software. The survival curve was constructed by the Kaplan–Meier method and multivariate Cox regression analysis was performed to explore the independent prognostic factors of 1- and 4-year mortality after CABG. The receiver operating characteristic (ROC) curves and the areas under the ROC curves (AUCs) were calculated to estimate the accuracy of BAR in predicting the outcomes. Subgroup analyses were also carried out.

Results

A total of 1,462 patients at 4-year follow-up were included, of which 933, 293, and 236 patients were categorized into the group 1 (≤ 6.45 mg/g), group 2 (>6.45 and ≤ 10.23 mg/g), and group 3 (>10.23 mg/g), respectively. Non-survivors showed an increased level of BAR at both 1- (p < 0.001) and 4-year (p < 0.001) follow-up compared with the survivors. The patients with a higher BAR had a higher risk of 1- and 4-year mortality following CABG (33.05 vs. 14.33 vs. 5.14%, p < 0.001 and 52.97 vs. 30.72 vs. 13.08%, p < 0.001, respectively). Cox proportional hazards regression model suggested a higher BAR as an independent risk factor of 1-year mortality (HR 3.904; 95% CI 2.559–5.956; P < 0.001) and 4-year mortality (HR 2.895; 95% CI 2.138–3.921; P < 0.001) after adjusting for confounders. Besides, the receiver operating characteristic (ROC) curves showed the better predictive ability of BAR compared to other grading scores at both 1- (0.7383, 95% CI: 0.6966–0.7800) and 4-year mortality (0.7189, 95% CI: 0.6872–0.7506). Subgroup analysis demonstrated no heterogeneous results of BAR in 4-year mortality in particular groups of patient.

Conclusion

This report provided evidence of an independent association between 1- and 4-year mortality after CABG and BAR. A higher BAR was associated with a higher risk of long-term mortality and could serve as a prognostic predictor in patients following CABG.