Present status of thromboembolic complications in patients with prosthetic heart valves

When the incidence of thromboembolism (TE) as a complication was investigated in 171 patients with prosthetic heart valves using pyrolytic carbon, 10 cases were identified in a mean follow-up period of 2.43 years. Of these 10, two patients had died. The incidence of TE as a percentage per patient--year was 2.41 on the whole, 2.15 in patients with aortic valve replacement (AVR), 2.48 in patients with mitral valve replacement (MVR) and 2.52 in patients with double valve replacement (DVR). It is evident that TE is still an important complication following prosthetic heart valve surgery and the patient's return to society. TE tended to occur somewhat more often in cases of MVR and DVR than in those of AVR. TE was apt to appear early in the postoperative period, often within a year, and was often seen in the brain. To prevent TE, it is necessary to carefully control blood coagulation by the administration of anticoagulants.