Five-year follow up of the ATS mechanical heart valve.

BACKGROUND AND AIM OF THE STUDY: Between January 1, 1997 and December 31, 2001, a total of 342 patients underwent aortic valve replacement (AVR) or mitral valve replacement (MVR) with the ATS Medical prosthesis. The initial three-year phase of this study took place under a United States Food and Drug Administration-approved investigational device exemption study. The study aim was to determine the incidence of valve-related events in up to five years of follow up after valve implantation, and to assess patient disturbance from valve noise.

METHODS

Patients were consecutively enrolled to undergo AVR or MVR with the ATS prosthesis. Follow up studies were conducted by patient questionnaire and/or telephone call. Follow up was 96% complete. AVR was conducted in 246 patients (80 with coronary bypass), and MVR in 96 patients (29 with coronary bypass).

RESULTS

The overall operative mortality was 2.6% (n = 9; AVR 3.2%, n = 8; MVR 1.0%, n = 1), with two deaths being valve-related (0.6%). In 878 patient-years (pt-yr) of follow up (613 pt-yr for AVR; 265 pt-yr for MVR) there were an additional 22 deaths. Five deaths (0.6%/pt-yr) were valve-related: two were neuroembolic (both MVR), one from endocarditis (AVR), and two from bleeding events (both AVR). Late valve-related complications (>30 days) included 17 episodes of major bleeding (11 AVR, 1.8%/pt-yr; six MVR, 2.3%/pt-yr), five permanent neuroembolic events (four AVR, 0.7%/pt-yr; one MVR, 0.4%/pt-yr); 16 transient neuroembolic events (10 AVR, 1.6%/pt-yr; six MVR, 2.3%/pt-yr); three transient peripheral emboli (two AVR, 0.3%/pt-yr; one MVR, 0.4%/pt-yr); four paravalvular leaks (two AVR, 0.3%/pt-yr; two MVR, 0.8%/pt-yr); and one episode of valve thrombosis (MVR, 0.4%/pt-yr; AVR, 0%/pt-yr). Reoperation was required in two patients: one AVR (paravalvular leak, 0.2%/pt-yr) and one MVR (replacement due to thrombosis, 0.4%/pt-yr).

CONCLUSION

These results indicate that intermediate-term results with the ATS mechanical prosthesis continue to be excellent, though further long-term follow up is warranted.