The catheter system of the present invention is directed to the removal of obstructions, such as thrombus and plaque, in blood vessels. In certain features, the catheter system of the present invention includes an elongated body defining a first lumen and including a distal portion, and an internal member configured for insertion into the first lumen, An internal member including an energy source configured to deliver treatment energy to the treatment site and a dissolution element coupled to the distal portion of the elongate body. The melting element may include a heating element, steam, and a balloon.本発明のカテーテルシステムは、血管内の、血栓及びプラークのような、閉塞物の除去に向けられる。特定の特徴において、本発明のカテーテルシステムは、第１の管腔を定め且つ遠位部分を含む細長い本体と、第１の管腔内への挿入のために構成される内部部材であって、治療エネルギを治療部位に給送するように構成されるエネルギ源を含む内部部材と、細長い本体の遠位部分に連結される溶解要素とを含む。溶解要素は、加熱要素、蒸気、及びバルーンを含んでよい。
