The insertion of a mechanical heart valve predisposes to thrombosis and embolism, and for this reason, individuals with mechanical valves who undergo dental/surgical procedures must take special precautions. In this article, we illustrate a protocol for anticoagulation during such procedures in individuals with mechanical valves.
 

Individuals with mechanical heart valves are anticoagulated in the long term with warfarin in order to reduce the risk of thromboembolism.¹ It has been calculated that the rate of major thromboembolism without anticoagulation is 8%, and that this risk is reduced by 75% with anticoagulation.²

The anticoagulated state is at risk of haemorrhage during dental or surgical procedures, but reduction or discontinuation of warfarin leads to increased risk of thrombo-embolic events. A similar scenario also exists in patients who have suffered recent venous thromboembolism and those with atrial fibrillation.

For this reason, intravenous heparin in used for the prevention of thromboembolism in the perioperative period when the International Normalisd Ratio (INR) is deliberately reduced, in order to shorten the period at risk to the greatest possible extent.
 

In this table, we demonstrate the current protocol used at the Hospital for Sick Children (London) and St. Luke’s Hospital (Malta) for the management of children on long-term warfarin who need dental or surgical procedures.