We reviewed twenty patients with mechanical prosthetic heart valves who underwent noncardiac operations which were performed in the presence of continual anticoagulant therapy. Prosthetic valves used were the SJM valve in nineteen patients and the Björk-Shiley valve in one. Twenty dental extractions in ten patients were performed with no reduction of warfarin, or the mean thrombotest value of 16%. Seven nonlaparotomy operations (polypectomy of the vocal cord in one patient, total hip joint replacement in one, insertion of a CAPD tube in one, pacemaker implantation in one, cataract operation in two and repair of tibial fracture in one) and three laparotomy operations (partial gastrectomy in two and hysterectomy in one) were performed under the thrombotest value of around 40% with partial reduction of warfarin. There was no difficulty in hemostasis during these operations. The only hemorrhagic complication in this series was bleeding from the abdominal wound in one patient two days after the gastrectomy when subcutaneous injections of heparin prolonged the ACT over 200sec. There were no thromboembolic complications. We conclude that dental extractions in patients with prosthetic heart valves can be safely performed with no reduction of warfarin and that the coagulability of thrombotest value of 40% is sufficient for hemostasis even in laparotomy operations.

In coronary artery bypass grafting (CABG), a portable suction unit was used in the superior mediastinum to evaluate whether it is effective in decreasing the amount of mediastinal hematoma and the incidence of hematoma-related postoperative complications. Out of 179 consecutive patients who underwent CABG at the Matsuyama Red Cross Hospital, in 97 patients (Group 1), two drainage tubes were placed as usual in the inferior mediastinum, while in 82 patients (Group 2), a small drainage tube of the portable suction unit was additionally placed in the superior mediastinum. The total amount of postoperative drainage in Group 2 was larger than that in Group 1 but there was no statistically significant difference. The postoperative mediastinothoracic ratio expressed in comparison with the preoperative value was 134±22% in Group 1 and 123±15% in Group 2 on the first postoperative day (POD), and 133±20% and 122±14%, respectively on the seventh POD (p<0.001). Regarding postoperative complications, there were two cases of mediastinitis and five cases of late cardiac tamponade in Group 1 but none in Group 2. The difference in the incidence of these complications between the two groups was statistically significant (p<0.02). We conclude that the portable suction unit effectively decreased the amount of mediastinal hematomas and the incidence of mediastinitis and cardiac tamponade following CABG.

To evaluate the extension of the indications for operation and up-to-date problems in the surgical therapy of the acquired valvular disease, 581 consecutive patients of prosthetic valve replacement from January 1974 through December 1987 were analysed. The age at operation was 39.1 years (range 22 to 68) at 1974, but increased to 51.9 years (range 9 to 75) at 1987 (p<0.05). Early mortality was 3 deaths in 9 patients (33.3%) who were older than 70 years old, but its range was 0% through 7.7% in the younger patient group (p<0.05). Hospital mortality of the combined valve procedure for aortic, miral and tricuspid valvular disease was analysed. It was higher in the group of tricuspid valve replacement (30.0%) than the group of tricuspid annuloplasty (8.3%) (p<0.01). The former group was in poor preoperative state (cachexia, total bilirubin>2mg/dl, mean right atrial pressure>10mmHg and systolic pulmonary artery pressure >75mmHg), compared to the latter group. The cases of re-replacement of the prosthetic valve increased since 1985. The incidence of poor prognosis after operation, that included early death, late death and retire from society, was 47.1% in NYHA Class TV, and from 0 to 15.8% in NYHA Class I to Class III (p<0.01). 60 cases underwent valve replacement for infective endo-carditis, and 16 urgent operations were required in 23 active stage operations. Total early and late mortality was higher in active stage operation (30.0%) than in healed stage operation (2.7%) (p<0.01). In these way, the extension of the indications for operation was carried on the patients of advanced age, combined valve procedure for multiple valve disease, valve re-replacement and infective endocarditis. The operative risk was high in the patients older than 70 years old, the patients who had the risk factors of multiple organ failure after operation, valve re-replacement in NYHA Class IV, and the urgent operation at active stage of infective endocarditis.