Risk of reoperation for aortic bioprosthesis dysfunction

The risk of reoperative valve replacement for failed aortic bioprosthesis may be overestimated, this being a dominant factor when selecting an initial prosthesis to be implanted in patients aged <70 years. The study aims were, first, to analyze the mortality and morbidity of redo aortic bioprosthesis replacement in the current era, and second, to identify preoperative risk factors and evaluate the EuroSCORE.

A total of 156 consecutive patients (111 men, 45 women; mean age 60.9 years; range: 23-87 years) who underwent reoperation for failed aortic bioprosthesis between 1990 and 2006 was reviewed in this retrospective, single-center study. Surgery was undertaken due to bioprosthesis degeneration (82.7%), bacterial prosthetic endocarditis (14.1%), paravalvular leak (1.3%) and other causes (1.9%). Emergency procedures were performed in 9% of patients. Associated procedures were coronary artery bypass grafting in 7.7% of patients, ascending aortic graft in 7%, and complete aortic root replacement in 6.4%. The predictive mortality was 8% according to the Additive EuroSCORE, and 15% according to the Logistic EuroSCORE.

Overall, the operative mortality was 3.8% (n = 6), and postoperative morbidity was low. The only multivariable predictor was emergency surgery (OR = 15.22, 95% CI = 1.68-86.43; p = 0.02). A mortality trend was associated with atrial fibrillation and NYHA class III/IV, but this was not statistically significant (p = 0.09 and p = 0.06, respectively). Associated procedures were not significant risk factors for mortality.

Reoperation for aortic bioprosthesis dysfunction can be performed with a low risk of mortality. It appears that this risk is overestimated by the EuroSCORE. Those patients who wish to avoid postoperative anticoagulant therapy may choose to receive this type of valve, even if reoperation is foreseeable.