Long-term survival after valve replacement with Björk-Shiley CC valves. Björk-Shiley Study Group

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Public Health

Background:

• Bjork-Shiley convexo-concave (BScc) valve recipients require accurate life expectancy data for clinical decisions.
• Limited information exists on the long-term outcomes and survival rates of BScc valves.
• Understanding determinants of survival is crucial for patient management and guideline development.

Purpose of the Study:

• To describe long-term survival and its determinants in the Dutch BScc valve recipient cohort.
• To compare mortality figures with the general population and existing prophylactic replacement guidelines.
• To assess the accuracy of current life expectancy estimates for BScc valve recipients.

Main Methods:

• Follow-up data collected for all Dutch BScc valve recipients (n=2,264) up to 1996.
• Kaplan-Meier product-limit method used for survival analysis over 15 years.
• Cox regression analysis identified determinants of survival; Standardized Mortality Ratios (SMRs) compared cohort mortality to the general population.

Main Results:

• 15-year survival rates were 55.0% (aortic), 40.8% (mitral), and 38.6% (double valve recipients).
• SMR was 4.2 in the first year post-surgery, decreasing to 2.0 thereafter and remaining constant.
• SMR varied by time since implantation, patient age at implantation, and valve position.

Conclusions:

• Current life expectancy estimates in prophylactic replacement guidelines for BScc valves often underestimate actual survival.
• Patient age, valve position, and time-specific risks are critical factors influencing post-surgery mortality.
• Personalized risk assessment, considering age-specific excess mortality rates, is recommended for BScc valve recipients.