An audit of anticoagulation and endocarditis prophylaxis after heart valve surgery.

OBJECTIVE

to audit anticoagulant control and endocarditis prophylaxis following heart valve surgery.

DESIGN

retrospective review of all 190 patients living in Canterbury who had heart valve surgery between January 1981 and December 1986 to determine the incidence of endocarditis and complications of anticoagulation.

RESULTS

there were 35 late deaths, of which nine were attributed to thromboembolism (3), major bleeding (2), or endocarditis (4). The rate of thromboembolic events, and major bleeding was 4.6 and 3.3/100 patient years of warfarin therapy respectively, while the incidence of late endocarditis was 0.96/100 patient years. Two episodes of endocarditis occurred after minor dental procedures performed without antibiotic prophylaxis. Many dentists indicated that they would not have recommended prophylactic therapy for these procedures. Some patients had inadequate recall of important details of anticoagulant control or endocarditis prophylaxis. Only 24% knew their latest prothrombin ratio, yet a survey of general practitioners revealed that, in their view, the majority of patients may be capable of monitoring their own anticoagulant therapy.

CONCLUSION

the incidence of potentially preventable long term complications of heart valve surgery is comparable to other series. Nevertheless, these complications could be reduced by better patient education possibly enhanced by greater involvement of the patient in their anticoagulant control. The indications for antibiotic prophylaxis for dental procedures should be broadened for this group of patients.