The position of bioprosthetic aortic root replacement
There is no perfect valve substitute for the individual patient with aortic valve and/or root disease as all prostheses are associated with certain valve-related events of varying nature. Careful weighting of the advantages and disadvantages of biological and mechanical valve substitutes tailored to the patient’s unique characteristics and preferences, is the current gold standard. Interestingly, there is a trend toward using a biological valve in younger patients (5, 56). Although evidence is lacking, perhaps this is emerging due to the potential prospect of transcatheter valve-in-valve therapy as a future solution for bioprosthetic SVD.
According to the ESC/EACTS guidelines on valvular heart disease, age limits contain an arbitrary element, and the choice of prostheses type should be individualized in a joint decision between the patient and doctor. Although SVD is known to occur earlier in younger patients (57), mechanical valve prostheses are not the preferred alternative in all young patients. Nevertheless, as individual patient norms, values and goals in life vary widely, the decision for a particular valve prosthesis should be individualized in a shared decision making process, and together with surgical experience, the most suitable surgical approach should be determined (2, 53). Our systematic review adds to the body of evidence by showing in a middle-aged patient population, undergoing bioprosthetic aortic root replacement, acceptable reintervention rates and valve-related event occurrence, and may be used as a benchmark to compare outcome with other type of prosthesis, e.g. Bentall and valve-sparing procedures.
LimitationsAs in all systematic reviews and meta-analysis of retrospective observational studies, limitations of this type of study should be taken into consideration (58). Furthermore, recall bias inherent to the retrospective design of all but one study and publication bias may have affected the observed outcome. In addition, the included studies represent a heterogeneous population of patients with different patient characteristics, with patients operated in different era spanning over 20 years, and considering improvements in anticoagulation strategies, medical management of valvular heart disease and surgical techniques over the past decades, which may have influenced outcome. Moreover, a lack of uniform data reporting as proposed by the guidelines (9) may have influenced the uniformity of the pooled data.
The pooled late outcome estimates are based on the linearity assumption, while occurrence of outcome events may not be linear in nature. However, due to the lack of randomized trials where homogeneous data are present, this meta-analysis was performed to provide an overview of published outcomes after bioprosthetic aortic root replacement.