The present invention advantageously provides self-tensioning occlusion devices, systems, and methods for percutaneous access and closure of vascular puncture sites. One device comprises a catheter body, an occlusion member, and a tensioning member. The occlusion member, such an expansible member, is disposed on a distal end of the body. The tensioning member, such as a spring or coil, is slidably disposed over the body and proximal the expansion member. Generally, during application, the tensioning member will be deployed against subcutaneous tissue so as to apply tension to the expansible member against the puncture site. The substantial hold once the tension is applied is then provided by external means, such as an anchoring clip.La prEsente invention concerne avantageusement des dispositifs docclusion auto-tendeurs, des systEmes et des procEdEs permettant laccEs percutanE et lobturation de sites de perforation vasculaire. Un dispositif comprend un corps de cathEter, un ElEment docclusion et un ElEment tendeur. LElEment docclusion, tel quun ElEment expansible, est disposE sur une extrEmitE distale du corps. LElEment tendeur, tel quun ressort ou un serpentin, est disposE coulissant sur le corps et A proximitE de lElEment expansible. Dune faÇon gEnErale, durant lapplication, lElEment tendeur sera dEployE contre le tissu sous-cutanE afin quune tension soit exercée sur lElEment expansible contre le site de perforation. Le maintien substantiel est ensuite assurE par un moyen externe, comme un clip dancrage, une fois la tension appliquEe.