Venous tos with chronic dvt, no blood flow trough subclavian vein, just collaterals. is there any point in doing first rib resection anymore?

Depends: It is all about risk benefit. If there is no symptoms and collateral a are adequate, i would not see any additional benefit from rib resection.

Probably not.: Acute subclavian vein thrombosis is treated by anticoagulation, and if the clot is due to tos, first rib resection is recommended to prevent recurrence or in anticipation of placing a stent into the subclavian vein. In your case, with chronic DVT and collaterals, there is no need for first rib resection. However, you have a potential for chronic stasis in you arm. You should see a vas. Surgeon.