Mortality risk factors from converting off-pump coronary artery bypass to on-pump coronary artery bypass

Two novel nomograms predict 30-day mortality after off-pump coronary artery bypass grafting

Background

With the development of surgical techniques and medical equipment, the mortality rate of off-pump coronary artery bypass grafting (CABG) has been declining year by year, but there is a lack of convenient and accurate predictive models. This study aims to use two nomograms to predict 30-day mortality after off-pump CABG.

Methods

Patients with isolated off-pump CABG from January 2016 to January 2021 were consecutively enrolled. Potential predictive factors were first screened by lasso regression, and then predictive models were constructed by multivariate logistic regression. To earlier identify high-risk patients, two nomograms were constructed for predicting mortality risk before and after surgery.

Results

A total of 1840 patients met the inclusion and exclusion criteria. The 30-day mortality was 3.97 % (73/1840) in this cohort. Multivariate logistic analysis showed that age, BMI<18.5 kg/m2, surgical time, creatinine, LVEF, history of previous stroke, and major adverse intraoperative events (including conversion to cardiopulmonary bypass or implantation of intra-aortic balloon pump) were independently associated with 30-day mortality. Model 1 contained preoperative and intraoperative variables, and the AUC was 0.836 (p < 0.001). The AUC of the K-fold validation was 0.819. Model 2 was only constructed by preoperative information. The AUC was 0.745 (p < 0.001). The AUC of the K-fold validation was 0.729. The predictive power of Model 1 was significantly higher than the SinoScore (DeLong's test p < 0.001).

Conclusions

The two novel nomograms could be conveniently and accurately used to predict the risk of 30-day mortality after isolated off-pump CABG.

No association between pulmonary artery catheter use and postoperative complications in off-pump coronary artery bypass grafting: a single-center pilot study

BACKGROUND

A pulmonary artery catheter is often used in cardiac surgery despite its uncertain effectiveness. The aim of this pilot study was to investigate the associations between the use of a pulmonary artery catheter and clinical outcomes in off-pump coronary artery bypass grafting.

METHODS

Patients over 20 years of age who had undergone off-pump coronary artery bypass grafting between December 2018 and November 2021 were enrolled in this single-center retrospective pilot study. The propensity score of pulmonary artery catheterization was calculated. Multivariate analysis including the propensity score as a covariate was performed to assess clinical outcomes. The primary outcome was the composite outcome of in-hospital death, unplanned intraoperative conversion to cardiopulmonary bypass, resuscitated cardiac arrest, mechanical circulatory support, myocardial infarction, stroke, new initiation of renal replacement therapy, inhaled nitric oxide, re-intubation and tracheostomy.

RESULTS

Among the 315 patients who were enrolled, 298 were included in the final analysis. A pulmonary artery catheter was inserted in 131 patients. There were 50 patients with the composite outcome including two in-hospital deaths. Multivariate logistic regression analysis showed that pulmonary artery catheterization was not significantly related to the composite outcome. Clinical outcomes worsened significantly as the number of anastomoses increased (odds ratio: 1.450, 95% confidence interval: 1.040-2.040, P=0.029).

CONCLUSIONS

Pulmonary artery catheterization did not improve the clinical outcomes in off-pump coronary artery bypass grafting in this pilot study.

Evaluation of the recovery after heart surgery following preoperative supplementation with a combination of beta-hydroxy-beta-methylbutyrate, L-arginine, and L-glutamine: a double-blind randomized placebo-controlled clinical trial

BACKGROUND

The preoperative period is a good time to improve nutrition status, compensate for nutrient deficiencies, and optimize immune function in patients' underlying surgery. In some medical conditions, supplementation with a combination of L-glutamine (Gln), β-hydroxy-β-methylbutyrate (HMB), and L-arginine (Arg) had promising effects on improving recovery. The present study aimed to evaluate the effect of supplementation with Gln/Arg/HMB in patients undergoing heart surgery.

METHODS

This randomized clinical trial was conducted on 70 patients undergoing cardiac surgery. Participants were requested to consume 2 sachets of a combination of 7 g L-arginine, 7 g L-glutamine, and 1.5 g daily HMB or placebo 30 days before operation. At the baseline and end of the study, left ventricular ejection fraction and the serum levels of troponin, creatine phosphokinase (CPK), CPK-MB, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin were measured. Also, the Sequential Organ Failure Assessment (SOFA) score, time of stay in hospital and intensive care unit (ICU), and postoperative complications were recorded after surgery.

RESULTS

In total, 60 preoperative patients (30 in each group) with a mean age of 53.13 ± 14.35 years completed the study (attrition rate = 85.7%). Subjects in the Gln/Arg/HMB group had lower serum levels of CPK-MB (median [IQR] = 49 [39.75] vs. 83 [64.55]; P = 0.011), troponin (median [IQR] = 2.13 [1.89] vs. 4.34 [1.99]; P < 0.001), bilirubin (median [IQR] = 0.50 [0.20] vs. 0.40 [0.22]; P < 0.001), and SOFA score (median [IQR] = 2 [2] vs. 5 [2]; P < 0.001) at end of the study compared to the placebo. Also, the time of stay in the hospital (median [IQR] = 5 [1] vs. 6 [3]; P < 0.001) and ICU (median [IQR] = 2.50 [1.00] vs. 3.50 [1.50]; P = 0.002) was lower in the Gln/Arg/HMB group.

CONCLUSION

The present study showed that perioperative supplementation with a combination of Gln, Arg, and HMB enhances the recovery, reduces myocardial injury, and decreases the time of hospital and ICU stay in cardiac surgery patients. These results need to be confirmed in a larger trial.

TRIAL REGISTRATION

IRCT.ir IRCT20120913010826N31. Registered on 13 October 2020.

Preoperative right ventricular dysfunction requires high vasoactive and inotropic support during off-pump coronary artery bypass grafting

Objectives

The association of preoperative RV function with hemodynamics during OPCAB or emergency conversion is not clear. The aim of this study was to investigate the association of vasoactive-inotropic score with tricuspid annular plane systolic excursion and tricuspid regurgitation in off-pump coronary artery bypass grafting, and to calculate the optimal cut-off value of tricuspid annular plane systolic excursion to predict emergency conversion to cardiopulmonary bypass.

Methods

Patients over 20 years of age who had undergone off-pump coronary artery bypass grafting between April 2015 and March 2020 were enrolled in this study. We retrospectively assessed the association of intraoperative maximum “vasoactive-inotropic score”, a weighted sum of various inotropes and vasoconstrictors, with tricuspid annular plane systolic excursion and tricuspid regurgitation. A receiver operating characteristic curve of conversion on tricuspid annular plane systolic excursion was also constructed.

Results

135 patients were included in final analysis. Conversion was performed in 10 cases. Multiple regression analysis showed that tricuspid annular plane systolic excursion, mild or more tricuspid regurgitation and experienced surgeon were significantly related to vasoactive-inotropic score. The receiver operating characteristic curve to predict conversion by tricuspid annular plane systolic excursion showed an optimal cut-off value of 15.0 mm and area under the curve of 0.808.

Conclusions

Tricuspid annular plane systolic excursion and tricuspid regurgitation were associated with vasoactive-inotropic score in off-pump coronary artery bypass grafting. The optimal cut-off value of tricuspid annular plane systolic excursion to predict emergency conversion was 15 mm.