Abstract: Objective  To compare the diagnostic value of transthoracic echocardiography (TTE) and chest X-ray (CXR) in identifying tip position of tunnel cuffed central venous catheter (TCC).  Method  Patients who underwent hemodialysis and used TCC for blood access at The Affiliated Hospital of Chengde Medical College from February 1, 2021 to December 31, 2022 were recruited as the research subjects. Demographic data was collected before and after the catheterization. TTE, CXR, and computerized tomography (CT) were used to determine the tip position of TCC, and CT result was used as the reference. The sensitivity, specificity, misdiagnosis rate, missed diagnosis rate, and positive/negative likelihood ratio for catheter tip localization by TTE and CXR were calculated. Chi square test was used to analyze the consistency between TTE, CXR and CT. ROC curve was used to evaluate the validity of different diagnostic methods.  Results  A total of 164 hemodialysis patients were included in the study. The diagnostic sensitivity, specificity and positive predictive values were 0.972, 0.923 and 12.132 respectively for TTE method, higher than the values of 0.900, 0.424 and 1.553 respectively for CXR method. The misdiagnosis and missed diagnosis rates were 0.082 and 0.034 respectively for TTE method, lower than the values of 0.584 and 0.100 respectively for CXR method. The diagnostic consistency between TTE and CT was higher than that between CXR and CT (TTE/CT:Kappa=0.896, χ2=0.068 and P=0.727; CXR/CT: Kappa=0.357, χ2=13.457, P＜0.001). The diagnostic accuracy of TTE was higher than that of CXR (TTE: AUC=0.984, 95% CI: 0.959～1.000, P＜0.001; CXR: AUC=0.794, 95% CI: 0.714～0.873, P＜0.001).  Conclusion  TTE is better than CXR for localization of the TTC tip.

Key words: Hemodialysis, Catheter dysplacement, Transthoracic echocardiography, Positioning of the tip