Kenji Minakata1, Shiro Tanaka2, Nobushige Tamura3, Shigeki Yanagi3, Yohei Ohkawa4, Shuichi Okonogi5, Tatsuo Kaneko5, Akihiko Usui6, Tomonobu Abe6, Mitsuomi Shimamoto7, Yoshiharu Takahara8, Kazuo Yamanaka9, Hitoshi Yaku10, Ryuzo Sakata1. 1. Department of Cardiovascular Surgery, Kyoto University Graduate School of Medicine. 2. Department of Pharmacoepidemiology, Kyoto University Graduate School of Medicine and Public Health. 3. Division of Cardiovascular Surgery, Kumamoto Central Hospital. 4. Division of Cardiovascular Surgery, Cardiovascular Center Hokkaido Ohno Hospital. 5. Division of Cardiovascular Surgery, Gunma Prefectural Cardiovascular Center. 6. Department of Cardiac Surgery, Nagoya University Graduate School of Medicine. 7. Division of Cardiovascular Surgery, Shizuoka City Shizuoka Hospital. 8. Department of Cardiovascular Surgery, Funabashi Municipal Medical Center. 9. Department of Cardiovascular Surgery, Tenri Hospital. 10. Department of Cardiovascular Surgery, Kyoto Prefectural University of Medicine.
Abstract
BACKGROUND: The aim of this study was to assess the long-term outcomes of aortic valve replacement (AVR) with either mechanical or bioprosthetic valves according to age at operation.Methods and Results: A total of 1,002 patients (527 mechanical valves and 475 bioprosthetic valves) undergoing first-time AVR were categorized according to age at operation: group Y, age <60 years; group M, age 60-69 years; and group O, age ≥70 years). Outcomes were compared on propensity score analysis (adjusted for 28 variables). Hazard ratio (HR) was calculated using the Cox regression model with adjustment for propensity score with bioprosthetic valve as a reference (HR=1). There were no significant differences in overall mortality between mechanical and bioprosthetic valves for all age groups. Valve-related mortality was significantly higher for mechanical valves in group O (HR, 2.53; P=0.02). Reoperation rate was significantly lower for mechanical valves in group Y (HR, 0.16; P<0.01) and group M (no events for mechanical valves). Although the rate of thromboembolic events was higher in mechanical valves in group Y (no events for tissue valves) and group M (HR, 9.05; P=0.03), there were no significant differences in bleeding events between all age groups. CONCLUSIONS: The type of prosthetic valve used in AVR does not significantly influence overall mortality.
BACKGROUND: The aim of this study was to assess the long-term outcomes of aortic valve replacement (AVR) with either mechanical or bioprosthetic valves according to age at operation.Methods and Results: A total of 1,002 patients (527 mechanical valves and 475 bioprosthetic valves) undergoing first-time AVR were categorized according to age at operation: group Y, age <60 years; group M, age 60-69 years; and group O, age ≥70 years). Outcomes were compared on propensity score analysis (adjusted for 28 variables). Hazard ratio (HR) was calculated using the Cox regression model with adjustment for propensity score with bioprosthetic valve as a reference (HR=1). There were no significant differences in overall mortality between mechanical and bioprosthetic valves for all age groups. Valve-related mortality was significantly higher for mechanical valves in group O (HR, 2.53; P=0.02). Reoperation rate was significantly lower for mechanical valves in group Y (HR, 0.16; P<0.01) and group M (no events for mechanical valves). Although the rate of thromboembolic events was higher in mechanical valves in group Y (no events for tissue valves) and group M (HR, 9.05; P=0.03), there were no significant differences in bleeding events between all age groups. CONCLUSIONS: The type of prosthetic valve used in AVR does not significantly influence overall mortality.