Impact of left ventricular ejection fraction on unplanned readmission after aortic regurgitation surgery: a single-center retrospective cohort study

Background and objective Aortic regurgitation (AR) is a common valvular heart disease. Despite advances in surgical techniques, unplanned readmission rates after surgery remain high. This study aimed to investigate the risk of postoperative unplanned readmission in patients with only mildly impaired left ventricular ejection fraction (LVEF 55%–60%) but concomitant left ventricular enlargement. Methods This single-center retrospective cohort study enrolled 841 adult patients diagnosed with aortic regurgitation who underwent surgical treatment at our hospital between January 2020 and December 2024. All patients underwent transthoracic echocardiography (TTE) within 3 days before surgery. The primary endpoint event was unplanned readmission during postoperative follow-up. Results During follow-up, 46 patients experienced unplanned readmission. Risk factor analysis for readmission indicated that patients in the LVEF 55%–60% group had significantly higher risk of postoperative readmission [HR (95% CI): 4.118 (1.488–11.397), P = 0.006]. Further Cox proportional hazards regression analysis revealed that LVEDD > 65 mm and LVEF <60% were significant risk factors for unplanned readmission during postoperative follow-up ( P < 0.05). Among all patients with unplanned readmissions, 21 cases had both LVEDD > 65 mm and LVEF < 60%, of whom 12 patients (57.14%) had an LVEF of 55%–60%. Cox regression analysis showed that patients meeting both risk factors had a significantly higher risk of unplanned readmission compared to those with neither risk factor [HR (95% CI): 2.548 (1.174–5.534), P = 0.018]. Conclusion Patients with mildly impaired left ventricular ejection fraction (LVEF 55%–60%) combined with significant left ventricular dilation (LVEDD >65 mm) constitute a high-risk cohort for unplanned readmission postoperatively. For patients with aortic regurgitation, even those exhibiting only mildly impaired LVEF, coexisting significant left ventricular dilation warrants heightened vigilance regarding readmission risk.