Predictors and Outcomes of Early Left Ventricular Dysfunction in Paediatric Patients Postoperative for Ventricular Septal Defect: A Retrospective Cohort Study Based on Myocardial Strain and Work

Background Early postoperative left ventricular (LV) dysfunction commonly occurs after ventricular septal defect (VSD) repair in paediatric patients. This study aimed to investigate its risk factors and impact on follow-up cardiac functional status. Methods We retrospectively enrolled patients with preserved LV ejection fraction (LVEF) (≥ 55%) undergoing isolated surgical VSD repair. Early postoperative LV dysfunction was defined as LVEF < 55% during hospitalisation. LV function parameters including myocardial strain and work were obtained. Cardiac functional recovery was assessed at 1, 3, 6, and 12 months post-discharge based on Ross Classifications. Results The cohort comprised 409 patients (3.00 [1.00–5.75] years; 50.4% male), with 82 (20.05%) developing postoperative LV dysfunction. Multivariate analysis showed preoperative LV global longitudinal strain (LV GLS), global work index (LV GWI) and global work efficiency (LV GWE), LV end-diastolic volume index(LVEDVi), moderate-to-severe systolic pulmonary arterial pressure(sPAP), large VSD size and prolonged cardiopulmonary bypass(CPB) time were significantly associated with postoperative LV dysfunction (all p  < 0.05). ROC analyses found that integrating LV GWI and GWE with clinical parameters (LVEDVi, VSD size, or sPAP) enhanced prediction (AUC 0.848–0.883, p  < 0.001). During follow-up, patients with postoperative LV dysfunction exhibited less favourable Ross classification recovery at 12 months after surgery. Conclusions In VSD patients with preserved LVEF, impaired preoperative myocardial strain and work indices predict early postoperative LV dysfunction, which correlates with persistent symptoms and cardiac dysfunction at 12-month follow-up. Integrated pre- and postoperative assessment using these novel parameters may optimise the management of this patient population.