Predicting Postoperative Outcomes in CABG: How GLS and PSS may Shape Future of Cardiac Prognosis, study suggests

The Need for Better Prediction in Cardiac Surgery

Coronary artery bypass grafting (CABG) remains one of the most frequently performed cardiac surgeries worldwide. Despite advancements and declining mortality rates, predicting which patients might experience immediate postoperative complications is a crucial challenge for clinicians. Traditionally, left ventricular ejection fraction (LVEF) has been a mainstay predictor, but new echocardiographic parameters—Global Longitudinal Strain (GLS) and Post-Systolic Shortening (PSS)—are emerging as powerful tools to enhance postoperative risk assessment.

Understanding GLS and PSS: Modern Tools for Cardiac Risk

GLS measures the deformation of the left ventricular myocardium, providing a sensitive indicator of cardiac function that can detect subtle changes not always apparent with LVEF. PSS, quantified using the post-systolic index (PSI), reflects myocardial deformation occurring after systole, often indicating regions of ischemia or delayed contraction. Both parameters are derived through advanced speckle tracking echocardiography, offering direct insight into myocardial health.

The Study at a Glance: Design and Methods

Published in the Annals of Cardiac Anaesthesia, this prospective observational study enrolled 71 patients aged 45–75 undergoing elective CABG at a tertiary care center. Both on-pump and off-pump procedures were included, with strict exclusion criteria to ensure a focused cohort. All patients underwent comprehensive preoperative echocardiography assessing LVEF, GLS, and PSI. Postoperative outcomes were meticulously tracked, including the vasoactive-inotrope score (VIS) at 24 hours, ICU stay, inotrope duration, and adverse events such as low cardiac output, acute kidney injury, arrhythmias, and mortality.

Major Findings: The Power of GLS and PSS

1. Superior Predictive Value:

Both GLS and PSI exhibited strong predictive power for immediate postoperative complications, with an area under the ROC curve (AUC) of 0.92 each—comparable, if not superior, to traditional LVEF (AUC 0.89).

2. Practical Cutoff Values:

The study identified practical cutoff points for risk prediction: a GLS of –14.6% and a PSI of 10.5. Patients exceeding these thresholds were significantly more likely to experience adverse postoperative events.

3. Independence from Traditional Risk Factors:

Variables like age, gender, hypertension, diabetes, and type of CABG (on-pump vs. off-pump) did not significantly differ between patients with and without adverse events, underscoring the unique predictive value of GLS and PSI.

4. Broader Implications for Practice:

The findings advocate for routine incorporation of GLS and PSI in preoperative assessment, enhancing the prognostic accuracy for patients undergoing CABG. This could lead to more tailored perioperative management and potentially better outcomes.

Conclusion: Toward Smarter, Safer Cardiac Surgery

This study strongly supports the use of GLS and PSI as superior, non-invasive predictors of immediate postoperative complications in CABG patients. By embracing these advanced echocardiographic parameters, clinicians can improve risk stratification and optimize care strategies for cardiac surgery patients.

Citation:

Sreedhar N, Patel GP, Holavanahalli A, Somanna SN, Unnisa F. Evaluating the use of post-systolic shortening and global longitudinal strain in predicting immediate postoperative course after coronary artery bypass grafting: Prospective observational study. Ann Card Anaesth 2026;29:89-94.