Predictive Value of Preoperative Myocardial Strain Imaging on Post-CABG Recovery

Background: Conventional left ventricular ejection fraction may not identify subtle myocardial dysfunction relevant to recovery after coronary artery bypass grafting. Global longitudinal strain provides a quantitative measure of myocardial deformation and may offer complementary prognostic information. Objective: To evaluate the association of preoperative global longitudinal strain with early postoperative cardiac output, intensive care unit stay, and complications following elective isolated coronary artery bypass grafting. Methods: This retrospective cohort study included 110 adults who underwent CABG at a tertiary cardiac centre in Central Punjab, Pakistan, between January 2022 and December 2024. Preoperative absolute GLS magnitude was classified as severely impaired (<11.0%), moderately impaired (11.1%–14.0%), or mild-to-preserved (>14.0%). Outcomes included early cardiac output, ICU stay, low cardiac output syndrome, new-onset atrial fibrillation, acute kidney injury, and a composite of postoperative complications. Group comparisons and adjusted regression analyses were performed. Results: ICU stay was 76.4 ± 20.5, 56.2 ± 14.8, and 49.1 ± 11.2 hours across severe, moderate, and mild-to-preserved GLS groups, respectively (p < 0.001). Corresponding cardiac output values were 3.9 ± 0.6, 4.6 ± 0.7, and 5.1 ± 0.7 L/min (p < 0.001). Low cardiac output syndrome occurred in 36.0%, 10.4%, and 0.0%, respectively (p < 0.001). Each one-percentage-point reduction in absolute GLS magnitude was associated with greater odds of postoperative complications (adjusted OR = 1.45, 95% CI: 1.12–1.88; p = 0.005). Conclusion: Impaired preoperative GLS was associated with poorer early recovery after CABG independently of baseline ejection fraction. Prospective validation is required before routine GLS-guided perioperative management can be recommended