Impact of Left Ventricular Ejection Fraction on 10-Year Mortality After Percutaneous Coronary Intervention or Coronary Artery Bypass Grafting: Is CABG Safer Than PCI in All Patients With Reduced Ejection Fraction?

Abstract Backgrounds The impact on vital prognosis at very long-term of percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) in patients with reduced ejection fraction (EF) remains to be elucidated. Objective To investigate the impact of left ventricular ejection fraction (LVEF) on 10-year mortality after PCI and CABG in the SYNTAX trial. Methods In the SYNTAXES study, 1,800 randomized patients were categorized into three groups according to the current guidelines; (1) reduced EF (rEF; LVEF ≤40%), (2) mildly reduced EF (mrEF; LVEF 41–49%), (3) preserved EF (pEF; LVEF ≥50%). The primary endpoint was 10-year all-cause mortality. Event rate up to 10 years was estimated according to the Kaplan-Meier method, and the log-rank test was performed to examine the differences among LVEF subgroups. The SYNTAX score 2020 (SS-2020) was compared between the patients with reduced (LVEF <50%) and preserved EF (LVEF ≥50%) in order to better refine their respective personalized vital prognosis and assess in cross-validation the value of the risk score. Results The population was stratified as rEF (n=168), mrEF (n=179), and pEF (n=1453). Ten-year all-cause mortality were 44.0% vs. 31.8% vs. 22.6% (P<0.001), in patients with rEF, mrEF and pEF, respectively. The significant interaction was not identified between LVEF classification and treatment (P interaction = 0.183). In patients with rEF, there was a tendency toward higher mortality in PCI group than CABG (52.9% vs 39.6%, P=0.054), and no significant differences in patients with mrEF (36.0% vs. 28.6%, P=0.273) and pEF (23.9% vs. 22.2%, P=0.275). According to the SS-2020, PCI was a relatively safe modality of revascularization in 37.8% of the patients with reduced EF (LVEF <50%). In the population with preserved EF (LVEF ≥50%), the proportion of patients eligible to PCI with predicted equipoise in mortality with CABG was 57.5%. Conclusion LVEF could an important factor for determining the revascularization treatment in patients presenting with complex coronary artery disease. Calculation of individualized 10-year prognosis using the SS-2020 may be a viable option in decision-making. Funding Acknowledgement Type of funding sources: None.