Abstract: Objective To identify the risk factors for low cardiac output syndrome（LCOS） in patients with heart valve disease after surgery by meta-analysis and to provide a basis for early identification，prevention and improve- ment of low cardiac output syndrome. Methods The relevant articles about postoperative LCOS risk factors in pa- tients with heart valve disease published from inception to December 2022 were searched in CNKI，Wanfang，VIP databale，CBM database，PubMed，CINAHL，Web of Science，Embase. After evaluating the quality of the literatures，the RevMan 5.4 software was used for meta-analysis. Results A total of 11 articles were included，with a total sample size of 2 117 cases. The risk factors of postoperative patients with LCOS were underweight （OR=3.59） or overweight（OR=1.34），old age（OR=3.74），hypertension（OR=2.84）， pulmonary hypertension（WMD=27.28），preoperative cardiac dysfunction （OR=20.52），water-electrolyte disorder （OR=3.42），preoperative renal insufficiency （OR=3.00）， postoperative arrhythmia （OR=4.34），excessive intraoperative blood loss （OR=3.76） and postoperative blood loss （OR= 4.48），long cardiopulmonary bypass time（OR=1.63），long aortic cross clamp time（OR=3.18），not use of intraoperative ultrafiltration（OR=0.27）. Conclusion According to the above risk factors，medical staff can make early risk warning judgement，prevention and treatment of LCOS patients，so as to take relevant interventions to prevent or improve LCOS-related symptoms of patients.

Key words: Cardiac Output, Low, Heart Valve Diseases, Risk Factors, Meta-Analysis, Evidence-Based Nursing