MAJOR HEPATIC RESECTION IN PATIENTS WITH A PROSTHETIC HEART-VALVE RECEIVING ANTICOAGULATION TREATMENT

We experienced two patients with a prosthetic heart valve, who underwe nt hepatic resection for hepatoma while on anticoagulation therapy. Pa tients with a prosthetic heart valve have the following characteristic s; an increased risk of thromboembolism due to diminished anticoagulat ion in the perioperative period, a greater risk of endocarditis due to the artificial material in the heart, and impaired cardiopulmonary fu nction including possible arrhythmia and heart failure. Furthermore, w hen such patients also have liver cirrhosis with a hepatoma, there is an increased risk of perioperative bleeding while on anticoagulation d ue to coagulopathy and also a risk of infection due to decreased cellu lar immunity. Patients with a prosthetic heart valve therefore require special care and attention whenever they have to undergo hepatic rese ction. With respect to anticoagulation, a minimal level is required to prevent bleeding and thromboembolism. Warfarin being administered pre operatively may be switched to heparin while closely monitoring the ac tivated clotting time (biomaterial valve: 130-150 sec, non-biomaterial valve: 150-180 sec); the heparin should then be changed back to warfa rin immediately after starting oral intake following operation. For th e prevention of infection, a broad spectrum antibiotic should be used prophylactically both intra-operatively and postoperatively. The cardi opulmonary function must also be carefully monitored. For the assessme nt of postoperative liver function, lecithin: cholesterol acyltransfer ase, sen.im bilirubin and albumin are useful because there is no relev ance of coagulation parameters such as prothrombin time under anticoag ulation.