Anticoagulation for pregnant patients with mechanical heart valves.

Management of a pregnant patient with mechanical heart valve is a complex issue for all health care providers involved in the care of such patients. Complications may arise at any stage due to the increased haemodynamic load imposed by pregnancy or because of impaired cardiac performance often seen in these patients. In addition, the use of various cardiovascular drugs in pregnancy (especially anticoagulants) may lead tofoetal loss or teratogenic complications. Additionally, the risk of thrombo-embolic complications in the mother is increased by the hypercoagulable state of pregnancy. In this review, we have attempted to draw inferences to guide management of such patients based on the available literature. It seems that in pregnant women with mechanical heart valves, recent data support warfarin use throughout pregnancy, followed by a switch to heparin and planned induction of labour. However, the complexity of this situation demands a cafeteria approach where the patient herself can choose from the available options that are supported by evidence-based information. Unfortunately there is no consensus on such data. An overview of the available literature forms the basis of this review. In conclusion, a guideline comprising pragmatic considerations is preffered.