Pulmonary Embolism After Coronary Artery Bypass Grafting: Systematic Review and Meta-Analysis

Background: Pulmonary embolism (PE) is a potentially life-threatening complication after coronary artery bypass grafting (CABG), yet its true incidence and impact on postoperative outcomes remain incompletely characterized. We performed a systematic review and meta-analysis to evaluate the incidence of PE following CABG and its association with mortality and resource utilization. Methods: PubMed, Embase, and the Cochrane Library were systematically searched to identify studies evaluating pulmonary embolism after isolated CABG. Study selection and data extraction were performed using predefined eligibility criteria. Random-effects meta-analyses were conducted to estimate pooled incidence and clinical outcomes associated with postoperative PE, including fatal PE, early all-cause mortality, ICU length of stay, and total hospital length of stay. Results: Seventeen studies comprising 1,553,900 patients undergoing CABG were included. The pooled reported incidence of PE following CABG was 1.62% (95% CI, 0.65-3.96; I 2 =99.4%; Figure 1). Among studies employing active postoperative screening, pooled PE prevalence was 12.67% (95% CI, 7.20-21.33; I 2 =86.6%; Figure 2). Fatal PE occurred in 0.27% (95% CI, 0.04-1.87). PE was associated with higher early all-cause mortality (OR 3.17; 95% CI, 1.43-7.03; Figure 3) and longer total hospital length of stay (MD 7.08 days; 95% CI, 3.26-10.90), whereas ICU length of stay was not significantly different (MD 0.46 days; 95% CI, -0.65 to 1.57). Smoking history was associated with postoperative PE in an unadjusted pooled analysis (OR 2.94; 95% CI, 1.89-4.56). In exploratory subgroup analysis, off-pump CABG cohorts had higher observed PE prevalence than on-pump cohorts (15.00% vs 6.50%; P for subgroup difference=0.0007). Conclusions: Pulmonary embolism following CABG is associated with substantially increased early mortality and prolonged hospitalization. Although the overall reported incidence is relatively low, substantially higher rates observed in screening studies suggest postoperative PE may be underrecognized. Enhanced risk stratification, surveillance strategies, and preventive measures warrant further evaluation to reduce the burden of this clinically significant complication.