Axillary subclavian vein thrombosis. Changing patterns of etiology, diagnostic, and therapeutic modalities. Fifty-two patients with axillary-subclavian vein thrombosis were treated in the last 10 years and were available for follow-up for at least 1 year. Eighteen of these were treated in the first 5 years, Group A, and 34 in the last 5 years, Group B. The causes in both Group A and Group B included respectively: effort or spontaneous 28 per cent and 29 per cent, catheter insertion related 17 per cent and 47 per cent, and malignancy or systemic disease 55 per cent and 24 per cent. None of the patients in Group A had noninvasive vascular testing (NIT). However, 27 patients in Group B had IPG/duplex imaging (NIT). All 18 cases in Group A and 27 cases in Group B were treated conventionally (anticoagulants). Seventy-three per cent of these had residual pain on exertion (venous claudication) and/or swelling. Fourteen of these cases had posttreatment NIT/venography. Four of these showed total resolution of the thrombus and all were symptom free. Ten had no resolution, and nine were symptomatic. Seven cases in Group B were treated with thrombolytic therapy. Five of these had total resolution of thrombus and were symptom free (71%). Two had no resolution with residual symptoms (29%) (statistically significant). In conclusion (1) More patients with axillary-subclavian vein thrombosis seen recently are catheter insertion related; 2) Diagnosis should be initiated with duplex imaging; and (3) Thrombolytic therapy significantly decreased residual symptoms and yielded better resolution than anticoagulants. 