BACKGROUND: Both unfractionated heparin (UFH) and low-molecular-weight heparin (LMWH) are approved for venous thromboembolism (VTE) prophylaxis. Which agent is superior remains controversial.

Many clinical trials and meta-analyses have shown that subcutaneous injections of LMWH are comparable to continuous infusions of UFH for initial therapy; [58] however, oral vitamin K antagonists ...