Mechanical versus bioprosthetic valves in aortic root replacement for acute type A dissection.

BACKGROUND: Aortic root replacement with a prosthetic valve is often required during type A aortic dissection repair (TAAD). With the advent of transcatheter aortic valve replacement (TAVR), the use of bioprosthetic valves has increased. METHODS: Patients undergoing acute TAAD repair from January 2007 through January 2025 were identified. Those who underwent aortic root replacement with a prosthetic valve were included. Multivariable Cox proportional hazards modeling was performed to evaluate the association between valve type and long-term mortality. RESULTS: Of the 587 patients who underwent type A aortic dissection repair, 158 patients received a prosthetic valve during root replacement. Mechanical valves (MV) were used in 74 (46.8%) and bioprosthetic valves (BV) in 84 (53.2%). The MV group was younger (51.6 vs. 65.3 years, P < 0.001), with similar rates of malperfusion syndromes between groups. 30-day mortality was 8.2% and comparable between the groups. Reoperation for bleeding was more frequent in the MV group but not statistically different (8.5% vs. 4.8%, P = 0.51). Cox Hazard analysis showed that bioprosthetic valve was independently associated a higher risk for long-term mortality (HR 3.23, 95% CI 1.39-7.69, P < 0.001). CONCLUSION: While reoperation for bleeding was more observed in patients receiving a mechanical valve, a bioprosthetic valve was associated with a higher risk for long-term mortality. While valve choice may not be available to patients in emergent high acuity situations, it is relevant when surgeons make decisions regarding appropriate prosthesis in patients undergoing surgery for acute TAAD.