I have blood clot in my interior vena cava extending down my left iliac vein. one vascular surgeon recommended against any procedure to clean out. ?

Sounds reasonable: You were put on warfarin (coumadin) to help prevent the clot from getting bigger and to prevent pieces from breaking off and going through your heart to your lungs. That's the right thing to do. Clot and anti-clot forces are like a see-saw in your body. Your own body will chomp away at the clot bit by bit over time. That's a good, safe approach.

Options: First of all, need to find out why you developed a clot. Look for clotting disorders, obstruction of the vein, malignancy or other causes. Treatment could include interventional radiology placement of a filter, thrombectomy, thrombolysis. Systemic anticoagulation with warfarin is necessary to reduce the risk of embolism side effect.

Seek 2nd opinion: Obviously depends on your individual circumstance, but most patients of your age that present to me with this condition I offer a procedure to fit it. Often there is May Thurner syndrome present. Most common procedure is venous thrombolysis (dissolving the clot) & left iliac stenting & this is pretty standard. Sometime temporary IVC filter also utilized. Blood thinners for 3-6 months also needed.