TY - RPRT TI - Elimination of the cloth sewing ring-metal interface in an effort to decrease thromboembolism. AU - A C Beall PY - 1989 DO - 10.1016/0003-4975(89)90639-5 UR - https://pubmed.ncbi.nlm.nih.gov/2774752/ ID - 2774752 ER -