a method of making a catheter balloon or other expandable medical device , and a balloon or other device formed thereby , in which at least a portion of a tubular , wrapped sheet of polymeric material is heated with laser radiation to form a fused seam extending along at least a section of the length of the tubular body . in one embodiment , the portion of the sheet heated by laser radiation is less than the entire area of the sheet , so that the fused seam is formed by heating portions of the sheet without heating sections of the sheet spaced apart from the fused seam . in one embodiment , the sheet of polymeric material comprises a polymer having a porous and preferably a node and fibril microstructure , which in one embodiment is selected from the group consisting of expanded polytetrafluoroethylene and expanded ultra high molecular weight polyethylene .