Conclusions
The study shows impaired survival and a notable lifetime risk of valve-related events after bioprosthetic aortic root replacement. The risk of thromboembolism is prominent, especially during earlier follow-up, suggesting higher risk of thromboembolism early after operation. Type of prosthesis, stented or stentless, is not associated with higher valve-related events. Moreover, this study could be used as a benchmark to compare outcome with other aortic root replacement procedures.
Background and aim of the study
In young patients with aortic root disease, composite mechanical graft replacement − Bentall-procedure− (1) is widely used due to its long-term durability (2). In elderly, biological aortic root replacement is more common, because reoperations are less prominent due to shorter life-expectancy and less structural valve degeneration (SVD) (3, 4). This age ‘turning-point’ however is arbitrary and biological valves are increasingly implanted in middle-aged patients recently. Interestingly, there are no large studies presenting outcome after bioprosthetic aortic root replacement and our knowledge is mainly based on data reported on aortic valve replacement. Additionally, most published studies have limited follow-up duration, which is a limitation for the interpretation of the results, particularly regarding SVD and reoperation hazard (5). Moreover, it is not known how a stentless biological valve prosthesis compares to stented prosthesis with regard to durability and valve-related outcome (6). Stentless valves may have hemodynamic advantages, especially in smaller aortic annulus, however, survival and long-term durability have not yet been proved (7).
Conspicuously, transcatheter aortic valve implantation (TAVI) procedures are gaining ground and with satisfying results, indicating that surgical aortic valve replacement will probably become limited in the near future (8). Nevertheless, when the aortic root is affected and should be replaced, surgery is still the only solution. To provide comprehensive data on outcome after bioprosthetic aortic root replacement and the possible effect of the type of prosthesis, we conducted a systematic review of observational reports on patient characteristics and valve-related morbidity, mortality and reintervention with both stented and stentless prostheses and explored potential determinants of outcome.