Clinical outcome after bioprosthetic aortic root replacement: A
Meta-Analysis and Microsimulation model
Abstract
Background and aim of the study This study aims to provide an overview
of clinical outcome after bioprosthetic aortic root replacement and
lifetime event-risk estimates of mortality and valve-related events, and
the potential effect of type of prosthesis used. Methods A systematic
literature search was conducted between January 2000 and August 2019.
Inclusion criteria: aortic root replacement in adults. Data were pooled
by inverse-variance weighting and entered a microsimulation model to
calculate lifetime event-risk and (event-free) life expectancy. Results
Of 2.106 publications, 31 were included (N = 5.227 patients, 74%
stentless valves). Mean age was 65.4 years (74% male). Pooled early
mortality was 5.5% (95% CI: 4.3-7.2%). During follow-up (mean 4.1
years, total 22.706 patient-years), late mortality was
4.8%/patient-year and reoperation 0.9%/patient-year.
Linearized-occurrence-rates for thromboembolism, endocarditis, and
hemorrhagic events:1.2; 0.9 and 0.5 %/patient-year; no significant
difference between stented and stentless prosthesis. Translating into a
60-year-old patient, an estimated life expectancy of 14 years (general
population: 22 years) and lifetime risks of thromboembolism,
endocarditis and reintervention of 21%, 13%, and 8%, respectively is
expected. 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.