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 (ePTFE) and expanded ultra high molecular weight polyethylene.