Significance of preoperative left ventricular ejection fraction in 5-year outcome after isolated CABG

Abstract

Background Pre-operative ejection fraction (EF) and comorbidities affect post-op outcomes. We aimed to compare the mortality and adverse events of patients with different baseline EF and also to evaluate the distribution of comorbidities in each EF group. Methods A total of 20,937 patients who underwent isolated coronary artery bypass graft (CABG) surgery from January 2006 to December 2016 was included. Patients were divided into three groups based on their pre-operative left ventricular EF as follows; (1) Normal: EF ≥ 50%; (2) Mild to moderately reduced: 50% < EF ≤ 35%; and (3) Severely reduced: EF < 35%. The backward elimination method was considered for multivariate Cox-regression analysis to locate predictors of mortality and non-fatal cerebro-cardiovascular events (CCVEs). The median follow-up time was 5.61 [3.12–8.0] years. Results The mean age in the total population was 60.94 ± 9.51 years and 73.6% of the total population was male. Diabetes mellitus was the common risk factor of mortality and CCVE in all EF groups. Impaired renal function (GFR < 60 ml/min) was associated with a higher risk of mortality after CABG regardless of EF level. The median 5-year mortality rate in patients with normal EF, mild-moderately reduced EF and severely reduced EF were 9.5%, 12.8%, and 22.7% respectively (P < 0.001). Although the trend of CCVEs was higher in severe left ventricle (LV) dysfunction, it was not statistically significant (p = 0.071). Conclusion Patients with severely reduced EF are at higher risk of mortality after CABG compared to those with higher EF levels; however, the rate of CCVEs may not be necessarily higher after adjustment for multiple pre-operative comorbidities.

Machine learning‐based prediction of 1‐year mortality in hypertensive patients undergoing coronary revascularization surgery

“…Also, VAP after cardiac surgery is related to poor prognosis with high mortality and long ICU stays 51 . The notable reverse relationship between low EF and risk of post‐CABG mortality has also been frequently reported by other investigations, 52‐55 with a dose–response relationship between reducing EF and risk of death has been revealed 53 . So far, lots of previous studies reported the pivotal role of age, 56,57 impaired glucose 58‐60 and lipid profile, 61,62 Hb levels, 63,64 serum creatinine, 65,66 and BMI 67,68 in estimating the early or late post‐CABG survival and mortality.…”

Non-Invasive Risk Assessment and Prediction of Mortality in Patients Undergoing Coronary Artery Bypass Graft Surgery

“…Severe LV systolic dysfunction is the most powerful prognostic factor for cardiovascular or SCD in patients with ischemic or non-ischemic cardiomyopathy, for whom an implantable cardioverter defibrillator (ICD) is recommended by the current guidelines to reduce the risk of mortality [ 16 ]. However, almost half of the deaths have reportedly occurred in post-MI patients with preserved or mildly reduced LV EF [ 7 , 17 ]. Therefore, identifying additional predictors associated with a worse outcome is particularly important in this kind of patient population with stable ischemic heart disease.…”

“…Left ventricular (LV) ejection fraction (EF) is the most widely used prognosis parameter after CABG surgery [ 4 , 5 ]. However, more than half of deaths after CABG occur in patients with preserved or moderately impaired LV systolic function, showing a low positive predictive value of LV EF [ 6 , 7 ]. Given the limitation of LV EF as a prognostic factor, continuous efforts are required to find additional risk stratifiers for patients undergoing CABG surgery.…”

Assessment of Left Ventricular Function After Coronary Artery Bypass Grafting

“…Res. J., 2024: 809. doi: https://doi.org/10.54112/bcsrj.v2024i1.809] 2 which may impact left ventricular function and surgical outcomes in CABG patients (10). Given the critical role of left ventricular function in predicting post-CABG outcomes and the scarcity of comprehensive data in the Pakistani context, there is a compelling rationale to investigate the assessment of left ventricular function and its impact on surgical outcomes in CABG patients within the local population (11).…”