BackgroundConcomitant iatrogenic proximal venous stenosis increases venous pressure and can be a risk factor for unfavorable outcomes of lymphaticovenular anastomosis (LVA) in extremities with secondary lymphedema. This study investigated the frequency and relevant factors of venous stenosis in patients diagnosed with secondary lymphedema who underwent LVA. MethodsPatients who underwent preoperative computed tomographic venography (CTV) and LVA for secondary lymphedema of the extremities from October 2018 to March 2022 were included. The incidence of proximal venous stenosis in the affected limb on preoperative CTV and the rate of endovascular intervention were compared between upper and lower extremities. Factors affecting proximal venous stenosis were identified through multivariable analysis using independent variables, including patient age, body mass index, comorbidities, smoking history, radiation therapy, duration of lymphedema, and location of lymphedema. ResultsA total of 211 patients were analyzed, including 83 patients with upper extremity and 128 patients with lower extremity lymphedema. The incidence of proximal venous stenosis in the preoperative CTV was 32.5% and 7.8% in upper extremity, and lower extremity lymphedema, respectively (P < .001). The incidence of venous stenosis requiring endovascular intervention was significantly higher in the upper extremity compared with the lower extremity (16.9% vs 6.3%; P = .014). In multivariable analysis, risk factors affecting incidence of venous stenosis requiring endovascular intervention was the patient age (P = .007) and upper extremity (P = .009). ConclusionsPreoperative evaluation and treatment of venous stenosis in extremities with secondary lymphedema are necessary before LVA surgery, particularly in upper extremity lymphedema.