Aim To investigate the correlation of intravenous ultrasound (IVUS) with coronary artery disease and left ventricular function in patients with non-ST segment elevation acute myocardial infarction (NSTEAMI). Methods A total of 90 patients with NSTEAMI admitted to Sanshui District People's Hospital of Foshan from June 2016 to December 2021 were selected as the study subjects. They were divided into single-vessel disease group (42 cases) and multi-vessel disease group (48 cases). The independent factors influencing the exacerbation of coronary artery disease in NSTEAMI patients were analyzed, and the linear graph prediction model was constructed and evaluated. The correlation between plaque load, eccentricity index, remodeling index, fibrous cap thickness and left ventricular ejection fraction (LVEF) was analyzed. Receiver operating characteristic (ROC) curve was used to analyze the predictive value of IVUS parameters for coronary exacerbation in patients with NSTEAMI. Results Serum cystatin C (CysC) ＞1.54 mg/L (OR＝2.5,5%CI:1.377～3.047), high sensitivity C-reactive protein (hs-CRP) ＞34.25 mg/L (OR＝1.2,5%CI:1.128～2.412), plaque load ＞60% (OR＝1.9,5%CI:1.232～2.405), eccentricity index ＞6.99 (OR＝1.7,5%CI:1.035～2.164), remodeling index ＞0.99 (OR＝1.0,5%CI:1.374～3.023), fibrous cap thickness ＜0.72 mm (OR＝0.3,5%CI:0.785～0.994) and LVEF ＜58% (OR＝0.6,5%CI:0.544～0.862) were independent risk predictors of coronary exacerbation in patients with NSTEAMI (P＜0.05). Pearson's test showed that plaque load, eccentricity index and remodeling index were significantly negatively correlated with LVEF (P＜0.05), and fiber cap thickness was significantly positively correlated with LVEF (P＜0.05). The results of ROC curve showed that the area under curve (AUC) of increased plaque burden, eccentricity index, remodeling index and decreased fiber cap thickness combined to predict the aggravation of coronary artery disease was 0.887 (95%CI:0.841～0.953), which was far higher than the AUC predicted by each index alone. The results of the lipopograph model based on seven independent predictors show that the AUC was 0.839, the C-index was 0.825, Hosmer-Lemeshow goodness of fit test showed a good fit (χ²＝1.475, P＝0.386), and it had a high net benefit value. Conclusions The plaque load, eccentricity index and remodeling index of NSTEAMI patients were negatively correlated with LVEF, and the fibrous cap thickness was positively correlated with LVEF. The diagnostic value of increased plaque burden, increased eccentricity index, increased remodeling index and decreased fiber cap thickness in predicting the exacerbation of coronary artery disease is much greater than that of each index alone.