Early and late outcome after aortic root replacement with a mechanical valve prosthesis in a series of 528 patients.

BACKGROUND: Aortic root replacement with a mechanical valve prosthesis is a widely accepted surgical technique. This study aims to evaluate short-term and long-term outcomes of this approach and to identify predictors of 30-day mortality.
METHODS: We retrospectively analyzed a consecutive series of 528 patients (mean age, 54±13 years) who underwent aortic root replacement for aneurysm (83%), acute type A dissection (15%), or endocarditis (2%) in the period between 1974 and 2008. The mean time of follow-up was 9.0±7.0 years (range, 0 to 36 years). Concomitant aortic surgery was performed in 71%, coronary revascularization in 18%, and mitral valve surgery in 3%. Selective antegrade cerebral perfusion was applied in 25% and deep hypothermic circulatory arrest in 28% of patients.
RESULTS: Overall 30-day mortality was 3.2% to 2.5% for elective surgery and 6.5% for urgent surgery. Morbidity included resternotomy for bleeding or tamponade (19%), pacemaker implantation (3.6%), myocardial infarction (4.0%), and neurologic damage (4.2%). Multivariate analysis revealed myocardial infarction (p<0.001) and the lack of glue use (p=0.018) as independent predictors of 30-day mortality. Subanalysis of the selective antegrade cerebral perfusion patients and the deep hypothermic circulatory arrest patients revealed infarction (p=0.005) and coronary artery disease (p=0.45) for selective antegrade cerebral perfusion and wrapping (p=0.035) for deep hypothermic circulatory arrest as independent risk factors. The survival rate was 87%, 73%, and 29% after 5, 10, and 25 years, respectively.
CONCLUSIONS: Aortic root replacement with a mechanical valve prosthesis can be performed safely with low mortality and acceptable morbidity. Perioperative myocardial infarction is the strongest independent risk factor of 30-day mortality.