This retrospective study investigated hemodialysis patients diagnosed with CRAT who underwent catheter replacement. The study found high procedural success and did not observe excessive deaths, fatal PE, or CRAT complications. Among patients with TCC-related RA thrombosis, a small proportion (5.6%) developed PE, all of whom were asymptomatic. Of the 158 patients who underwent CTA after the procedure, only 3 (1.9%) developed new PE. We also observed a reduction in CRAT length after treatment with catheter exchange and antiplatelet therapy. Additionally, catheter patency was well maintained post-procedure.

In this study, the primary reason for improved procedure success was the utilization of percutaneous SVC puncture for hemodialysis catheter placement in patients where catheter replacement had previously failed. This technique significantly enhanced the success rate of catheter placement in hemodialysis patients with occlusion of the innominate vein or internal jugular vein [11]. The American College of Chest Physicians (ACCP) guidelines [12] recommend to remove catheters 3–5 days after anticoagulation treatment, and continue anticoagulation as long as central venous catheters remain in place. Several treatment modalities have been used alone or in combination for managing thrombus, including catheter-directed therapy (CDT), surgical thrombectomy, and systemic thrombolysis [9, 13]. Due to the absence of systematic studies employing a standardized protocol, comparing the effectiveness of different treatment options for CRAT has proven challenging. An initial systematic review of CRAT compared thrombolysis, surgery, anticoagulation, and no therapy, revealing similar survival rates across groups, except for those receiving no therapy [14, 15]. There are currently no guidelines for the management of hemodialysis patients with CRAT [12]. The treatment recommendations presented in these literatures are mainly based on strategies for PE, which may not be applicable. Management of asymptomatic PE is particularly under-informed due to insufficient evidence, despite its prevalence being approximately 2.6% [15]. Anticoagulation may not be necessary in patients with a single subsegmental PE and with no additional risks of venous thrombus embolism [16, 17]. Considering our study population of elderly maintenance dialysis patients, we opted not to use anticoagulants before and after the procedure due to their potential to increase the risk of bleeding. Instead, we administered oral antiplatelet drugs to manage their condition.

It was reported that more than 90% of PE is caused by lower limbs deep venous thrombosis [18]. However, it remains unclear whether endovascular procedures, such as percutaneous balloon dilatation (PTA), increase the risk of PE. This study found that, though in close proximity to the pulmonary vessels, the incidence of PE in the CRAT was only 5.6% among the preoperative patients, similar to that of the upper-extremity deep-vein thrombosis-related PE [19, 20]. During the follow-up period, only 3 patients (1.9%) developed new PE on chest CTA, which is significantly lower than previous studies [9, 10], suggesting that catheter replacement combined with antiplatelet therapy can reduce the incidence of postoperative PE. Furthermore, The low incidence of PE in our study may be related to the long-term chronic accumulation of thrombus caused by TCCs, which is not easy to be fragmented and scattered during the operation. Among our patients, the median catheterization time was 29 months, longer than the typical indwelling time [21]. However, the speculation warrants more research. Finally, no symptomatic PE were observed even with an endovascular therapy, possibly because of fast blood flow and small thrombi dissolved by heparinization among maintenance dialysis patients. The length of CRAT decreased after treatment may be due to new catheter placement and antiplatelet therapy. Postoperative catheter patency was high can be due to all patients were treated with oral dipyridamole, which delayed thrombosis to a certain extent [8].

There are some limitations in the study. First, this was a retrospective research without a control group, so the results were largely exploratory. More rigorous and larger-scale prospective randomized studies are needed to confirm the effectiveness and safety of the proposed TCC procedure. Additionally, infections related to right atrial thrombus were excluded from the study, potentially contributing to the lower reported incidence of pulmonary embolism and mortality.