Estimation of the Lifetime Risk for Reoperation after the Ross Procedure According to the Patient's Age at the Initial Procedure: A Simulation Study Based on Data from the German Ross Registry

Objectives: Conventional aortic valve replacement (AVR) in the young, active patient represents a suboptimal solution due to the need for anticoagulation with mechanical valves and the reduced durability of biological valves. Reoperations on either the autograft or homograft are the Achilles' heel of the Ross procedure. Based on our current understanding on patient's survival and risk for autograft or homograft reoperation we aimed estimate a patient's lifetime (up to 75 years of age) probability of experiencing a reoperation according to the patient's age at the initial Ross procedure.

Methods: Data from 1779 patients (1339 adults; mea age: 44.7 ± 11.6 years) operated between 1992–2013 in 9 German centers were included. Mean follow-up was 8.3 ± 5.1 years (range 0–24.3) with a total cumulative follow-up of 14288 years. 662, 213 and 35 patients had a follow-up of at least 10, 15 and 18 years respectively. The hazard for autograft, homograft and death was estimated using parametric as well as non-parametric survival methods and was decomposed to identify temporal patterns as well as factors exhibiting a significant influence. A Markov model was employed with patients entering the initial state (Ross at age X) and moving through one transition state to four absorbing states. Several assumptions on the autograft and homograft reoperation hazard function were evaluated (constant or accelerated failure) based on the up to now observed data. For the competing risk of death, several assumptions on the mortality hazard were evaluated (equal to general population or multiplicative penalization).

Results: Based on our current understanding of the hazard for autograft, homograft and death after the Ross procedure, the probability of experiencing at least one reoperation up to the age of 75 ranges between ≈0.5 (patient aged 20 year) and ≈0.13 (patient age 60 years). The results of the stochastic model utilizing a Weibull hazard function for the risk for autograft or homograft reoperation and a multiplicative penalization of the hazard of death (factor:1.3) is presented in the Fig. 1 below.

Fig. 1

Conclusion: According to our current understanding of the risk for autograft, homograft reoperation and death, only a minority of patients will require a reoperation until reaching the age of 75 years old. These results may have some implications for decision making and may aid patient-physician discussion on the choice of procedure prior to aortic valve intervention in young patients.