Does Aortic Valve Replacement Restore Normal Life Expectancy: a Twenty-Year Relative Survival Study

Background This 20-year relative survival study investigates life expectancy in defined age cohorts and evaluates the role of patient, procedural and peri-operative variables on absolute survival after aortic valve replacement. Methods Absolute long-term survival variance was calculated using Cox regression analysis in 585 consecutive aortic valve replacement patients. Relative survival curves in defined age groups were constructed using age- and gender-matched controls. Results There were 12 peri-operative deaths (2.1%), and 11 further deaths (1.9%) during the first year. 154 patients (26.3%) died subsequently and 408 patients (69.7%) were alive after 20 years. Relative survival increased with age: in patients over 68 survival was equivalent to an age- and gender-matched population. Patient risk indicators for decreased absolute survival included age, Parsonnet score, additive and logistic EuroSCORE, and for increased absolute survival included weight, body surface area, and stroke volume. Procedural risk indicators for decreased absolute survival included bypass time, use of a tissue valve, and prosthesis-patient mismatch with size 19 valves, and for an increased absolute survival included use of a mechanical valve. Post-operative risk indicators for decreased absolute survival included ITU stay, ventilation time, transfusion, haemorrhage volume and new-onset atrial fibrillation/flutter. Strong risk indicators included intra-aortic balloon pump use, and dialysis. Conclusions Patients over 68 years discharged from hospital after aortic valve replacement had a similar 10-year survival as an age- and gender-matched population. In this age cohort surgery restored the patient’s normal life expectancy. Key words: aortic valve replacement; absolute survival predictors; relative survival