Optimal warfarin initiation dosing in patients with mechanical mitral valve replacements (MVRs) is debatable.

Warfarin initiation dose is lowered empirically in clinical institutions to balance the early increased postoperative warfarin sensitivity, leading to increased consumption of enoxaparin as a bridging agent.

This study compared two initiation dosing protocols of warfarin 5 mg versus 3 mg using low molecular weight heparin (enoxaparin) as a bridging agent in the MVR patient population at a single institution.

Patients receiving the 5 mg initiation dose achieved therapeutic international normalized ratio more rapidly, hence minimizing the cost of enoxaparin bridging.