Association between catheter tip position and catheter-related thrombosis in patients with cancer: A Retrospective cohort study

BACKGROUNDCatheter-related right atrial thrombosis (CRAT) is an uncommon but potentially serious complication of central venous catheters (CVCs).The relationship between catheter-tip position, particularly extension beyond the cavoatrial junction (CAJ), and CRAT in patients with cancer remains insufficiently defined. AIMTo determine the occurrence of CRAT among adult patients with cancer with CVCs at Sultan Qaboos Comprehensive Cancer Care and Research Center and to evaluate the association between catheter-tip position -particularly extension into the right atriumand the occurrence of echocardiographically detected CRAT. METHODSThis single-center retrospective cohort study included adult oncology patients with a CVC in situ who underwent baseline and follow-up echocardiography during 2024.Patients were classified according to catheter-tip position as not crossing the CAJ (group A) or crossing the CAJ into the right atrium (group B).The primary outcome was CRAT occurrence according to the catheter-tip position.The thrombus location and depth of catheter advancement were additionally evaluated. RESULTSAmong 373 eligible patients, 342 (91.7%) were classified as group A and 31 (8.3%) as group B. CRAT was identified in 11 patients overall (2.9%), occurring in 1/342 patients (0.3%) in group A compared with 10/31 (32.2%) in group B (P < 0.0001).Despite being significantly younger than patients in group A (35.5 ± 15.5 years vs 52.7 ± 16.9 years, P < 0.001), patients in group B had a markedly higher occurrence of CRAT, while other 4 / 27 measured clinical characteristics and thrombotic risk factors were broadly comparable between groups.Among the 11 CRAT cases, all six patients with catheter tips extending > 1 cm beyond the CAJ developed right atrial wall thrombi, whereas all five patients with catheter tips positioned ≤ 1 cm beyond the CAJ developed catheter-tip-associated thrombi (P = 0.002). CONCLUSIONCatheter-tip extension into the right atrium was associated with a higher occurrence of CRAT in patients with cancer.Among patients with CRAT, catheter tips extending > 1 cm beyond the CAJ were more frequently observed in association with right atrial wall thrombi, whereas more proximal tip positions were associated with catheter-tip thrombi.These findings highlight an observed relationship between catheter-tip position and CRAT pattern without establishing causality.Larger prospective studies are needed to validate these observations and further characterize the relationship between catheter-tip position and CRAT.